ML090440477

NPDES Permit No. TN0026450 - Shad Complaint Response

ML090440477
Person / Time
Site:	Sequoyah
Issue date:	02/10/2009
From:	Cleary T Tennessee Valley Authority
To:	Urban R Office of Nuclear Reactor Regulation, State of TN, Dept of Environment & Conservation
References
Download: ML090440477 (104)

Text

Tennessee Valley Authority, Post Office Box 2000, Soddy Daisy, Tennessee 37384-2000 I February 10, 2009 State of Tennessee Department of Environment and Conservation Chattanooga.

Environmental Field Office Division of Water Pollution Control State Office Building, Suite 550 540 McCallie Avenue Chattanooga, Tennessee 37402-2013 Attention:

Richard Urban, Ph.D., Environmental Field Office Manager

Dear Dr. Urban:

TENNESSEE VALLEY AUTHORITY (TVA) -SEQUOYAH NUCLEAR PLANT (SQN) -NPDES PERMIT NO. TN0026450

-SHAD COMPLAINT RESPONSE On Friday February 6, 2009 at 0905 Ann Hurt of SQN's Environmental Staff received an email from Leetha Abazid stating: "I need a letter on TVA letterhead mailed to the Chattanooga Field Office stating what actually occurred, including dates, temperatures, number and, species affected DO readings, and location.

We had received a complaint from a resident of the county stating that many species of fish including threadfin shad were dead at the pond near the wing wall (intake bay) at SQNP. Please have this letter to TDEC by February 11, 2009." This correspondence is in response to that email.Sequoyah has not observed any dead fish in the Intake' Forebay, notwithstanding the presence of shad impinged on the traveling screens. Monitoring in boats and visual inspections confirm this (see attached photos). During the period of December 1, 2008 and February 6, 2009 there were very cold water temperatures in the Tennessee River.The attached chart (Attachment

1) shows adequate dissolved oxygen, cold river temperatures, and high condenser cooling water (CCW) differential pressure (DP).Occurrences of high CCW DP are directly related to drops in river temperature.

Differential pressure monitoring is used to measure the buildup of waterborne material on the screens and is required to ensure safe, unobstructed operation of the CCW system. On these days, the cause of the high DP events was the buildup of lethargic shad on the intake screens. To reduce the differential pressure, the shad are removed from the intake screens by a CCW backwash system. The numbers of shad have varied episodically from dozens to thousands.

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The fish impinged on. the CCW traveling screens were primarily threadfin shad. The lethargy of these fish is caused by cold-stress from river temperatures below 50'F.Threadfin shad are very sensitive to low water temperature and do not feed or move extensively when the temperature falls below 50'F. Due to this natural wintertime phenomenon, shad are unable to swim or maintain their position in the water column and cannot resist the flow of water in the withdrawal zone for the plant intake pumping station. Fost (2006) reported that threadfin shad began to exhibit reduced or impaired swimming performance at 7.5°C (45.5°F).

The shad that are suffering from cold-stress are pulled against the CCW traveling screens, and subsequently removed by a CCW backwash system. Similar events with lethargic fish are occurring throughout the Valley due to arctic cold fronts that have cooled water temperatures in Tennessee's reservoirs.

On 2/5/09, the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> average water temperature at the bottom of the Sequoyah skimmer wall dropped below 42 0 F. Until water temperatures increase above 50'F shad will be susceptible to cold-stress.

Enclosed are the following two documents.

The first is TVA Sequoyah Nuclear Plant NPDES Permit No. TN0026450 316(b) Monitoring Program Fish Impingement at Sequoyah Nuclear Plant During 2005 through 2007. This document was originally sent to Mr. Paul E. Davis, Director and the Chattanooga Environmental Assistance Center on 12/19/2007.

The second, EPRI -The Role of Temperature and Nutritional Status in Impingement of Clupeid Fish Species, discusses the episodic impingement of large numbers of certain fish species, particularly in the winter, at many power plant cooling water intake structures.

If you have any questions or need additional information, please contact Ann Hurt at (423) 843-6714 or myself at (423) 843-6700.Sincerely, Stephanie A. Howard Principal Environmental Engineer Signatory Authority for Timothy P. Cleary Site Vice President Sequoyah Nuclear Plant Enclosures cc (Enclosures):

U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 Fost, B. A. 2006. Physiological

& Behavioral Indicators of Shad Susceptibility to Impingement at Water Intakes. M. S. Thesis, University of Tennessee, Knoxville.

45pp.

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31i."v"N V ZZ2 TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT NPDES PERMIT NO. TN0026450 316(b) MONITORING PROGRAM FISH IMPINGEMENT AT SEQUOYAH NUCLEAR PLANT DURING 2005 THROUGH 2007 ENVIRONMENTAL STEWARDSHIP AND POLICY 2007 TABLE OF CONTENTS List of Tables .............................................................................................

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i List of Figures ................................................................................................................

ii List of Acronym s ..............................

v ..........................................................................

ii Introduction

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I Plant Description

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I M ethods ...........................................................................................................................

2 MoribundlDead Fish .........................................

2 Data Analysis ...................

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2 Results and Discussion

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3 Summary and Conclusions

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4 References

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5 LIST OF TABLES Table 1. List of Fish Species by Family, Scientific, and Common Name Including Numbers Collected In Impingement Samples During 2005-2007 at TVA's Sequoyah Nuclear Plant ..................

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6 Table 2. Estimated Annual Numbers, Biomass, and Percent Composition of Fish Impinged by Species at Sequoyah Nuclear Plant During 2005-2007

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7 Table 3. Numbers of Fish Impinged at Sequoyah Nuclear Plant by Month and Percent of Annual Total During Year-One, Year-Two, and for Both Years Com bined ....................................................................................................

8 Table 4. Total Numbers of Fish Estimated Impinged by Year at Sequoyah Nuclear Plant and Numbers Following Application of Equivalent Adult and Production Foregone Models During 2005-2007

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8.... a Table 5. Percent Composition (By Number and Weight and After EA and PF Models Applied) of Major Species of Fish Impinged at Sequoyah Nuclear Plant Between December 18, 2001 and February 25, 2002 .....................

9 Table 6. Percent Composition (By Number and After EA and PF Models Applied)of Major Species of Fish Impinged at TVA's Sequoyah Nuclear Plant During 1980-1985 and 2005-2007

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I .................................

10 i LIST OF FIGURES Figure 1. Aerial photograph of Sequoyah Nuclear Plant including CCW intake structure, skimmer wall, intake basin, and diffuser cooling pond .........

11 Figure 2. Average daily generation (MW) and intake flow (cfs) at Sequoyah Nuclear Plant during January 2005 through January 2007 .................

12 Figure 3. Estimated weekly fish impingement at Sequoyah Nuclear Plant during 2005-2007

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13 Figure 4. Comparison of estimated weekly fish impingement at Sequoyah Nuclear Plant during historical and recent monitoring periods .......................

14 Figure 5. Ambient daily (24-hr avg) water temperature at Sequoyah Nuclear Plant intake during historical (1986-2006) and recent (2005-2007) impingement m onitoring

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15 LIST OF ACRONYMS AM&M Aquatic Monitoring and Management CCW Condenser Cooling Water CWA Clean Water Act EA Equivalent Adult EPA Environmental Protection Agency EPRI Formerly known as the Electric Power Research Institute MW Megawatt PIC Proposal for Information Collection PF Production Foregone RFAI Reservoir Fish Assemblage Index SQN Sequoyah Nuclear Plant TDEC Tennessee Department of Environment and Conservation TRM Tennessee River Mile TVA Tennessee Valley Authority ii Introduction Sequoyah Nuclear Plant (SQN) withdraws condenser cooling water (CCW) from the Tennessee River and is subject to compliance with the Tennessee Water Quality Act and the federal Clean Water Act (CWA). Section 316(b) of the CWA requires the location, design, construction, and capacity of cooling water intake structures to reflect the best technology available for minimizing adverse environmental impact.Impingement mortality is a potential mechanism for adverse impacts and is defined as the condition in which fish and/or shellfish are trapped or impinged against an intake screen and often killed in the process. In response to the Environmental Protection Agency (EPA) issuance of a 2004 rule for implementing Section 316(b), a rule subsequently suspended in 2007, and in accordance with a Proposal for Information Collection submitted to Tennessee Department of Environment and Conservation (TDEC) in 2005, Tennessee Valley Authority (TVA) conducted impingement monitoring at SQN to update the impingement database for potential intake effects. This report presents impingement mortality data collected from the CCW intake screens from January 2005 through January 2007 with comparisons to historical impingement data.Historical impingement mortality data from 1980-1985 assessed effects on the aquatic community of Chickamauga Reservoir for operational monitoring discharge permit requirements.

An additional impingement study was conducted during December 2001 through February 2002, to compare peak numbers of fish impinged to historical impingement monitoring.

No significant impacts were observed to the aquatic community in either of these studies and both datasets were similar in the numbers and species impinged.Per an agreement reached in September 2001 with TDEC, Division of Water Pollution Control, TVA performs Reservoir Fish Assemblage Index (RFAI) (Hickman and Brown 2002) sampling annually to demonstrate that SQN operation is not impacting the balanced indigenous population in Chickamauga Reservoir.

The primary reason for gathering these data is to support the continuation of a Section 316(a) thermal variance for SQN. However, the RFAI monitoring also gives an indication of the overall adverse environmental impact of plant operations to the reservoir fish assemblage and benthic community, including impacts from the plant's cooling water intake.Plant Description SQN is located on the west shore of Chickamauga Reservoir at Tennessee River Kilometer (TRK) 779.7 (TRM 484.5) (Figure 1). Construction began in 1970 and commercial operation for Unit I began in 1981 and Unit 2 in 1982. The two units (pressurized water reactors) have a total nameplate rating of 2,441 megawatts (MW).Natural draft cooling towers enable SQN to operate in an open or helper mode. In open mode operation, with both units at maximum power, total water demand is 72.45 m 3/s (2,558 cfs). CCW is drawn from Chickamauga Reservoir into the intake channel through an opening approximately 165 m (541 ft) long and 3 m (9.8 ft) high near the bottom of a skimmer wall situated near the river channel. This allows SQN to withdraw cooler water from the lower portion of the water column. From the intake channel, water passes through six, 3 m wide traveling screens to the intake pumps. Mesh openings on screens are 0.95 cm 2 (3/8 in 2). Both units were near full load during January 2005 through January 2007 (Figure 2). Average daily generation for the two combined was 2,373 MW; Unit 1 averaged 1,186 MW and Unit 2 averaged 1,187 MW. Six intake pumps were usually in operation, resulting in an average daily intake flow of 71.8 m 3/s (2,536 cfs).Velocity at the traveling screens averaged 37 cm/sec (1.2 fps).I Methods Impingement sampling began on January 25, 2005, and weekly samples were collected through January 15, 2007. To simplify comparisons in this report, data from January 25, 2005 through January 23, 2006 will be referred to as Year-One, and from January 30, 2006 through January 15, 2007, as Year-Two.

To collect each sample, intake screens were rotated and washed on a prearranged schedule by the plant assistant unit operator to remove all fish and debris. After 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, screens were again rotated and washed with Aquatic Monitoring and Management (AM&M) crew on site. Fish and debris were collected in a catch basket constructed of 9.5 mm (3/8 in) mesh located at the end of the sluice pipe where the monitoring crew removed and processed the sample. Fish were sorted from debris, identified, separated into 25 mm (1 in) length classes, enumerated, and weighed. Data were recorded by one member of the AM&M crew and checked and verified (signed) by the other for quality control. Quality Assurance/Quality Control procedures for impingement sampling (TVA 2004) were followed to ensure samples were comparable with historical impingement mortality data.Moribund/Dead Fish Fish collected from a 24-hour screen wash were usually all dead when processed.

Incidental numbers of fish which appeared to have been dead for more than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (i.e., exhibiting pale gills, cloudy eyes, fungus, or partial decomposition) were not included in the sample. Also, during winter, threadfin shad occasionally suffer die-offs or stress from cold-shock and are impinged after death or in a moribund state (Griffith and Tomljanovich 1975, Griffith 1978). If these die-off incidents were observed, they were documented to specify that either all, or a portion of impinged threadfin shad collected during the sample period were impinged due to cold-shock and may not have been impinged otherwise.

Any fish collected alive were returned to the reservoir after processing.

Data Analysis Impingement data from weekly 24-hour impingement samples were extrapolated to provide estimates of total fish impinged by week and total for each year of study. In rare situations when less than a 24-hour sample was possible, data were normalized to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Historical data collected during 1981-1984 were averaged over a 52- week period, while data collected during 1985 were from January through July only. During 2001-2002, impingement data were collected from December through February and therefore represent only the winter period.To facilitate the implementation of and compliance with the EPA regulations for Section 316(b) of the CWA (Federal Register Vol. 69, No. 131; July 9, 2004), prior to its suspension by EPA, fish lost to impingement were evaluated by extrapolating the losses to equivalent reductions of adult fish, or of biomass production available to predators in the case of forage species. In conformance with methods utilized by EPA in its Technical Development Documents in support of the Phase II Rule (EPA 2004), EPRI (Formerly known as the Electric Power Research Institute) has identified two models for extrapolating losses of fish eggs, larvae, and juveniles at intake structures to numbers or production of older fish (Barnthouse 2004). The Equivalent Adult (EA) model quantifies entrainment and impingement losses in terms of the number of fish that would have survived to a given future age. The Production Foregone (PF) model applies to forage fish species to quantify the loss from entrainment and impingement in terms of potential forage available for consumption by predators.

These models require site-specific data 2 on the distribution and abundance of fish populations vulnerable to entrainment and impingement.

TVA also used these models to determine the "biological liability" of the CCW intake structure based on the EPA guidance developed under the suspended rule.Results and Discussion Impingement sampling at SQN from January 2005 to January 2007 resulted in collection of 2,889 fish (22 species) during Year-One and 5,766 fish (21 species) during Year-Two (Table 1). Threadfin shad were predominate (91%) in the samples, followed by bluegill (3%), freshwater drum (2%), and channel and blue catfish (1% each) (Table 2). All other species contributed less than 1% of the total number collected.

Annual estimates of number impinged and corresponding biomass are compared by species and year in Table 2. Rate of impingement was highest during November and December during Year-One (2005-2006), while peak impingement occurred during August, October, and November during Year-Two (2006-2007) (Table 3, Figure 3). Estimated annual impingement was calculated by extrapolating impingement rates from weekly samples.An estimated 20,223 fish were impinged during Year-One and 40,362 during Year-Two;of these, the majority was threadfin shad (Table 2). Estimated impingement during Year-Two was more than double the impingement estimate during Year-One due to collection of greater than two times more threadfin shad during Year-Two.With the exception of samples collected during 1980-1982, annual historical impingement estimates for SQN were similar to those calculated during this study (Table 4, Figure 4). Although estimated impingement was much higher from 1980-1982, threadfin shad accounted for the majority of fish impinged in these samples as well as in samples collected during 1983-1985.

The 2001-2002 data represented samples collected only in the winter when peak numbers are typically impinged at SQN (Kay and Baxter 2002). Impingement estimates for all species, except threadfin shad, were low and consistent with the 1980-1985 historical data and with data collected during the current study. Threadfin shad was the dominant species collected during 2001-2002, comprising 97% of the total number collected and 74% of the total weight (Table 5).Gizzard shad, freshwater drum, and sunfish comprised a notable proportion of historic impingement samples following threadfin shad (Tables 5 and 6). This was similar to the dominant species collected during this study.Threadfin and/or gizzard shad typically comprise over 90% of fish impinged on cooling-water intake screens of thermal power stations in the Southeastern U. S. (EPRI 2005).They also comprise an average of 35%-56% of total fish biomass where they occur (Jenkins 1967). Threadfin shad have a high fecundity rate, move in large schools, and are intolerant to cold temperatures, often resulting in high mortality rates in winter.These traits are probably major contributing factors to the annual and seasonal fluctuation in numbers of fish impinged at SQN. A recent study by Fost (2006) indicated that cold-stressed threadfin and gizzard shad can be classified as either impaired or moribund.

Impaired shad could recover if environmental conditions improved and would therefore not die if not impinged.

Moribund fish on the other hand, are assumed to not be able to recover and die regardless of impingement.

Fost's data indicated that threadfin shad began to exhibit reduced or impaired swimming performance at 7.5 0 C (45.5-F).Plotted weekly ambient water temperatures for SQN (Figure 5) appear to be negatively correlated with peak shad impingement as previously reported by numerous studies 3 (EPRI 2005, Griffith and Tomljanovich 1975, Griffith 1978; McLean et al., 1980). No die-offs of threadfin shad were observed at SQN during the two years of monitoring by AMM crews or were reported by power plant personnel.

Application of the. EA and PF models to the total numbers estimated impinged resulted in reduced numbers of fish which would have been expected to survive to either harvestable (EA) size/age or to provide forage (PF) (Table 4). This reduced number is considered the "biological liability" resulting from plant CCW impingement mortality based on the guidance developed for the now suspended 316(b) regulations.

The numbers of fish representing SQN's biological liability for Year-One and Year-Two were 1,868 and 821, respectively.

As part of TVA's Vital Signs Monitoring Program resident fish communities were sampled in Chickamauga Reservoir upstream TRK 789.4 (TRM 490.5) and downstream TRK 775.7 (TRM 482.0) of SQN since 1999 (Baxter and Simmons 2007). Resulting data were analyzed using a multi-metric RFAI to rate the overall health and condition of the fish community at these sampling locations.

Fish communities at both sites upstream and downstream from SQN have averaged a rating of "Good" during 1999-2006, indicating that SQN is not adversely impacting the resident fish community (Baxter and Simmons 2007).Summary and Conclusions Fish impingement rates at SQN during 2005-2007 were much lower than during 1980-1981, but were similar to historical data collected from 1982-1985.

Threadfin shad has been the dominant species impinged during all years sampled and comprised 91% of fish impinged during this study. Biological liability after EA and PF reduction was low.Low impingement rates at SQN and "Good" RFAI scores for sites just upstream and downstream of SQN indicated that the SQN CCW intake is not adversely impacting the Chickamauga Reservoir fish community.

4 References Bamthouse, L. W. 2004. Extrapolating Impingement and Entrainment Losses to Equivalent Adults and Production Foregone.

EPRI Report 1008471, July 2004.Baxter, D. S. and J. W. Simmons. 2007. Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge.

Tennessee Valley Authority, Aquatic Monitoring and Management, Knoxville, Tennessee.

EPA. 2004. NPDES -Final Regulations to Establish Requirements for Cooling Water Intake Structures at Phase II Existing Facilities; Final Rule. 69 FR No.131, July 9, 2004.EPRI. 2005. Large-Scale Natural Mortality Events in Clupeid Fishes: A Literature Review. Palo Alto, CA. EPRI Report.Fost, B. A. 2006. Physiological

& Behavioral Indicators of Shad Susceptibility to Impingement at Water Intakes. M. S. Thesis, University of Tennessee, Knoxville.

45pp.Hickman, G. and Brown, M. L. 2002. Proposed methods and endpoints for defining and assessing adverse environmental impact (AEI) on fish communities/populations in the Tennessee River reservoirs.

In Defining and Assessing Adverse Environmental Impact Symposium 2001. TheScientificWorldJOURNAL 2(S1), 204-218.Griffith, J. S. and D. A. Tomljanovich.

1975. Susceptibility of threadfin shad to impingement.

Proceedings of the 29th Annual Conference of the Southeastern Association of Game and Fish Commissioners.

223-234.Griffith.

J. S. 1978. Effects of low temperature on the survival and behavior of threadfin shad, Dorosoma petenense.

Transactions of the American Fisheries Society.107(1): 63-70.Jenkins, R. M. 1967. The influence of some environmental factors on standing crop and harvest of fishes in U. S. reservoirs.

Pages 298-321 in Reservoir fishery resources symposium.

Southern Div. Am. Fish. Soc., University of Georgia, Athens.Kay, L.K. and D. S. Baxter. 2002. Effects of impingement on the aquatic populations in Chickamauga Reservoir.

Tennessee Valley Authority, Resource Stewardship, Knoxville, TN.McLean, R. B., P. T. Singley, J. S. Griffith, and M. V. McGee. 1980. Threadfin shad impingement:

Effect of cold stress. NUREG/CR-1044, ORNUNUREGITM-340, Environmental Sciences Division, Publication No. 1495, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, 89 pp.Tennessee Valley Authority.

2004. Impingement Counts. Quality Assurance Procedure No. RSO&E-BR-23.1 1, Rev 1. TVA River Systems Operation and Enyironment, Aquatic Monitoring and Management Knoxville TN. 11 pgs.5 Table 1. List of Fish Species by Family, Scientific, and Common Name Including Numbers Collected in Impingement Samples During 2005-2007 at TVA's Sequoyah Nuclear Plant.Total Number Impinged Family Scientific Name Common Name Year-One Year-Two Clupeidae Alosa pseudoharengus Alewife 10 4 Dorosoma cepedianum Gizzard shad 17 25 Alosa chrysochloris Skipjack herring 10 10 Dorosoma petenense Threadfin shad 2,529 5,373 Cyprinidae Pimephales notatus Bluntnose minnow 0 2 Pimephales vigilax Bullhead minnow 1 3 Moxostoma spp. Unidentified redhorse 0 1 Notropis atherinoides Emerald shiner 1 0 Ictaluridae Ictalurus furcatus Blue catfish 25 40 Ictalurus punctatus Channel catfish 50 32 Pylodictis ofivaris Flathead catfish 3 11 Ameiurus natalis Yellow bullhead 1 0 Atherinidae Labidesthes spp. Unidentified silverside 0 1 Moronidae Morone saxatilis Striped bass 4 0 Morone chrysops White bass 2 4 Morone mississippiensis Yellow bass 24 10 Centrarchidae Lepomis spp. Unidentified sunfish 0 1 Lepomis macrochirus Bluegill 122 120 Lepomis auritus Redbreast sunfish 2 1 Lepomis microlophus Redear sunfish 1 0 Micropterus salmoides Largemouth bass 5 5 Micropterus punctulatus Spotted bass 1 13 Pomoxis nigromaculatus Black crappie 0 47 Pomoxis annularis White crappie 3 3 Poecillidae Gambusia affinis Western mosquitofish 1 0 Percidae Sandercanadense Sauger 1 0 Sclaenidae Aplodinotus grunniens Freshwater drum 76 60 Total Number of Fish 2,889 5,766 Total Number of Species 22 21 6 Table 2. Estimated Annual Numbers, Biomass, and Percent Composition of Fish Impinged by Species at Sequoyah Nuclear Plant During 2005-2007.

Estimated Number Estimated Biomass (g)Percent Year- Year- Year- Year- Composition Species One Two Average One Two Average by Number Threadfin shad 17,703 37,611 59,612 70,539 " 5076$ 91 Bluegill 854 840 6,636 5,054 3 Freshwater drum 532 420 476 63,686 28,385 46,036 2 Channel catfish 350 224 287 78,309 25,683 lur96 1 Blue catfish 175- 280 228; 67,998 70,021 ".6;0i0 1 Black crappie 0 329 1,65 0 385 193: 1 Gizzard shad 119 175 f -6,902 2,506 , 704 T Yellow bass 168 70 119 -. 6,545 2,779 :' 4662 _`-- T Skipjack herring 70 70 70 7 9,982 14,770 12 37 _ T Alewife 70 28 49 560 791 676&_ T Flathead catfish 21 77 -.49 6,391 67,326 TN36 859._ T Spotted bass 7 91 49 700 217 459r-',,,_

T Largemouth bass 35 35 35 .231 91 161 T White bass 14 28 ý,:21 .. 3,857 5,117 ... 4487 T White crappie 21 21 21 i 91 42 67 T Bullhead minnow 7 21 14 ý , 35 49 42 T Striped bass 28 0 14, 140 0 >70, T Redbreast sunfish 14 7 2,065 987 ti1526 T Bluntnose

.. .minnow 0 14 ..7. 0 14 7... .... T Unidentified-redhorse 0 7 ~ 4' 0 3,605 _1,803_ý T Emerald shiner 7 .0 4 7 0 '4 T Yellow bullhead 7 0 4 35 0 '1& T Unidentified silverside 0 7 0 21 1,T Redear sunfish 7 0 0 Unidentified sunfish 0 7 l 0 28 14 T Western mosquitofish 7 0 470 4~T Sauger 7 0 4 3,010 0 T,505, T TOTAL 20,223 40,362 30,293 316,869 298,410 307,640 7 Table 3. Numbers of Fish Impinged at Sequoyah Nuclear Plant by Month and Percent of Annual Total During Year-One, Year-Two, and for Both Years Combined.Table 4. Total Numbers of Fish Estimated Impinged by Year at Sequoyah Nuclear Plant and Numbers Following Application of Equivalent Adult and Production Foregone Models During 2005-2007.

Sr9 19801982V 1982-1983,:19831984

-1984985 "2005420060

!2"62007 Extrapolated Annual Number 94,528 81,158 20,685 41,076 27,195 20,223 40,362 Impinged Number after EA 4,851 5,843 2,256 4,162 2,761 1,868 821 and PF Reduction 8 Table 5. Percent Composition (By Number and Weight and After EA and PF Models Applied)of Major Species of Fish Impinged at Sequoyah Nuclear Plant Between December 18, 2001 and February 25, 2002.Species Percent by Percent by Composition Number Weight Threadfin shad 96.98 74.09 Bluegill 0.80 0.64 Freshwater drum 0.77 14.68 Gizzard shad 0.43 1.33 Alewife 0.23 0.82 Channel catfish 0.28 1.33 Striped bass 0.24 0.46 Mosquitofish 0.13 0.01 Logperch 0.03 0.08 Flathead catfish 0.02 4.68 Bluntnose minnow 0.02 0.03 Redear sunfish 0.02 0.02 Redbreast sunfish 0.01 0.73 Largemouth bass 0.01 0.27 White crappie 0.01 0.83 9 Table 6. Percent Composition (By Number and After EA and PF Models Applied) of Major Species of Fish Impinged at TVA's Sequoyah Nuclear Plant During 1980-1985 and 2005-2007.

1980-1981 1981-1982 1982-1983 1983-1984 1984-1985 2005-2006 2006-2007% after % after % after % after %after % after % after Species % by PA and %by PA and %by PA and %by PA and % by PA and % by PA and % by PA and Composition Number EF Number EF Number EF Number EF Number EF Number EF Number EF Threadfin shad 83 63 72 46 49 25 70 44 65 42 87 59 93 77 Lepomis 8 16 4 7 8 12 9 14 6 .12 4 9 2 5 Gizzard shad 4 3 9 6 22 11 2 1 8 5 1 0 0 0 Skipjack herring 0 0 0 0 1 1 3 2 4 3 0 0 0 0 Ictaludds 0 0 0 0 2 7 1 5 1 4 3 15 2 10 Freshwater drum 2 3 8 14 12 19 9 15 6 9 3 6 1 2 Spotted bass 0 0 1 2 0 0 0 0 0 0 0 0 -1 White crappie -3 0 -0 1 2 0 0 0 0 0 0 1 2 Yellow perch 3 -6 1 6 3 0 0 0 0 YellowWhite 3 3 11 2 6 4 3 1 6 2 bass I___Bullhead minnow 0 0 0 0 0 0 0 0 2 1 0 0 0 0 Total 97 94 97 92 98 91 95 94 93 96 99 95 99 99 Dash denotes not a major species during that year.10

~4.<~pM ~Tennes, Figure 1. Aerial photograph of Sequoyah Nuclear Plant including CCW intake structure, skimmer wall, Intake basin, and diffuser cooling pond.I1 1400o 1300 1200 5 100 -'11 800 -.v 400 I -- ---- -- --100 .. .. ..---200 -900 3000 27000- --------6 2 00 --~~ -v -~ -*4~ --- ----1500.-~~~~ --j~ -<4 4 ~3000 2005 2006 Figure 2. Average daily generation (MW) and intake flow (cfs) at Sequoyah Nuclear Plant during January 2005 through2Janua 2007.D J 2007 12 9000 8000 7000 S6000 E LL.-5000 , 4 0 0 0 2000 1000 0* ~1~ ~*~-e %.4.A ~~ ~a ~---~,'-~ ~ ~Sample Week.Figure 3. Estimated weekly fish impingement at Sequoyah Nuclear Plant during 2005-2007.

13 2000C 16000 02~~~ ________83-841................

................................................

S160000 .7~. __________

14, 000~eeWe ek We ek We eek Wee Week Week We ekWe Ja e a pr I May 1 June Jul u Sept Oct No De Ja Sample Week Fiue4. Comparison of estimated weekly fish impingement at Sequoyah Nuclear Plant during historical and rcn monitoring periods.14 90 70 ------- --- ---- ----- ----- --- ---- -..-- ------ ------ .-.-66 ... ....... ... .... ..... ... -.. --.........

... .... -----------.---

... ...-- ---.-----7 0 ... .... ....-. ...... ............-- ---- .... ..... .. .. ... .. .... .... ....- .- .... .... ..1 62 -..........

.-- -.------..-

---..----.......

5 4 ------------ Jan 2005 -Doc 2005-Jan 2006 -Jan 2007 46-Average 1981 -1985 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Figure 5. Ambient daily (24-hr avg) water temperature at Sequoyah Nuclear Plant intake during historical (1981-1985) and recent (2005-2007) impingement monitoring.

15 ELECTRIC POWER Thrnei. RoEoEARCH aNoTITUTu The Role of Temperature and Nutritional Status in Impingement of Clupeid Fish Species The Role of Temperature and Nutritional Status in Impingement of Clupeid Fish Species 1014020 Final Report, March 2008 EPRI Project Manager D. Dixon ELECTRIC POWER RESEARCH INSTITUTE 3420 Hillview Avenue, Palo Alto, California 94304-1338

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SHAPING THE FUTURE OF ELECTRICITY are registered service marks of the Electric Power Research Institute, Inc.Copyright

© 2008 Electric Power Research Institute, Inc. All rights reserved.

CITATIONS This report was prepared by Oak Ridge National Laboratory Environmental Sciences Division PO Box 2008 Oak Ridge, TN 37831 Principal Investigators M. Bevelhimer B. Fost C. Coutant S. M. Adams ASA Analysis & Communication, Inc.90 East Main Street P.O. Box 57 Washingtonville, NY 10992 Principal Investigators J. Vile W. Dey This report describes research sponsored by the Electric Power Research Institute (EPRI).The report is i corporate document that should be cited in the literature in the following manner: The Role of Temperature and Nutritional Status in Impingement of Clupeid Fish Species. EPRI, Palo Alto, CA: 2008. 1014020.iii PRODUCT DESCRIPTION Episodic impingement of high numbers of juvenile and adult clupeid fish species such as gizzard and threadfin shad, menhaden, and herring is a common occurrence, particularly during winter at many power plant cooling water intake structures (CWIS). In fact, annual impingement estimates are frequently dominated by the large numbers of clupeids' associated with these episodes.Minimizing the number of fish impinged at CWIS is important for both environmental protection and operational reasons. This report presents the results of investigations of two environmental factors, cold shock and nutritional state, that are known to contribute to the impingement of clupeids.

These results can be used to help predict when impingement events are likely to occur and to assess the relative contribution of project operations and natural causes to fish impingement.

Results and Findings A review of the literature on mass mortalities of clupeid species, particularly gizzard and threadfin shad, revealed that such events are common, especially in larger freshwater lakes, rivers, and reservoirs.

However, research to date into the causes of this mortality as well as the general physiological responses of clupeids to potential environmental stressors is limited. The principal reasons for such die-offs often vary among species. Laboratory studies confirm that cold temperatures and cold shock resulting from a rapid decline in temperature can reduce swimming endurance in gizzard and threadfin shad and render them more susceptible to impingement.

The results of these studies will be useful for identifying the environmental conditions under which one might expect the cause of impingement to be largely of natural origin. For example, when thermal regimes at a CWIS are similar to those that resulted in loss of equilibrium in laboratory experiments, i.e., < 2 'C for gizzard shad and < 5 'C for threadfin shad, we would expect that the bulk of impinged fish were not killed directly by impingement.

This study also identified physiological indicators of susceptibility to impingement such as hematocrit and condition factor whose measurement could potentially be used to predict or explain episodic impingement events. The use of multiple indicators of stress helps to explain confounding stressors that may be present in natural ecosystems.

Using physiological and performance-level indicators to assess impingement susceptibility appears promising, but further studies are needed to evaluate the relative importance of cold shock and nutritional status on impingement.

Challenges and Objectives Under the Clean Water Act (CWA) §316(b), the applicant for a National Pollutant Discharge Elimination System (NPDES) permit must demonstrate that the location, design, construction, and capacity of its cooling water intake structure represents Best Technology Available (BTA)for minimizing adverse environmental impact. As of preparation of this report, the U.S.Environmental Protection Agency (EPA) is re-writing, per a 2007 U.S. Appeals Court finding,'the Rule to implement CWA §316(b) for existing power plants (Phase II Rule). Many studies v have demonstrated a relationship between the incidence of natural mortality for several fish species (particularly clupeids) and increased power plant impingement.

EPA has recognized the need to evaluate naturally moribund fish and shellfish entering CWIS. In the now remanded Phase II Rule, EPA noted that estimates of impingement mortality should be based on the impingement and harm of healthy fish, not the incidental capture of moribund and dead fish. The revised EPA Phase II Rule may retain the requirements in the previous Rule; and the key challenge will be to demonstrate technical, defensible criteria for the identification of impinged fish that were already dead or dying when they entered the intake. The development of these criteria is the subject of this report and future EPRI research.Applications, Values, and Use This report is planned as a technical support document providing information and ideas EPRI members can use when discussing impingement compliance options with permitting agencies in areas where there are occurrences of high episodic natural mortality of fish.EPRI Perspective This report provides information to EPRI members to support their CWA §316(b) compliance efforts. Most notably, the report supports the documentation of the natural occurrence of dead and moribund fish, thereby reducing estimates of annual impingement mortality that can be attributed to processes and structures associated with a power plant's CWIS.Approach This issue was initially addressed by reviewing and summarizing the technical literature on natural mortality events exhibited by clupeids for the purpose of examining the relationship between naturally stressed and moribund fish and impingement at CWIS, as well as for designing laboratory studies to investigate key relationships.

The project team then conducted laboratory studies on the responses of two common freshwater shad species (gizzard and threadfin) to rapid reductions in water temperatures and their potential for recovery from cold shock. Additional laboratory studies investigated the relationship between various physiological indicators of stress and the susceptibility of impingement by these species.Keywords-Clean Water Act §316(b)Impingement Cooling Water Intake Structures Fisheries Fish Kills vi ACKNOWLEDGMENTS We thank Bob Reider (DTE Energy), John Petro (Exelon), Dave Michaud (WE Energies), Jules Loos (Consultant), Bill Garret (Alabama Power), Casey Knight (Auburn University), and Rob Reash (American Electric Power) for reviewing an earlier draft of this report. Joe Vondruska (EA Engineering, Science, and Technology, Inc.) provided valuable data on impingement rates at Ohio River power plants. Allison Fortner (ORNL) and Glenn Cada (ORNL) contributed to final editing and document preparation.

James Scott (University of Tennessee) helped collect fish for the laboratory experiments.

Cover photo of threadfin shad collected during an episodic event at a power plant on the Ohio River.vii CONTENTS 1 INTRO DUCTIO N ....................................................................................................................

1-1 2 NATURAL MORTALITY EVENTS IN CLUPEID FISHES: A LITERATURE REVIEW ..........

2-1 Introduction

...........................................................................................................

..............

2-1 Threadfin shad ......................................................................................................................

2-2 G izzard Shad ........................................................................................................................

2-5 Alewife ....................................................................................................

I ...............................

2-7 Atlantic & Gulf M enhaden .......................................................

2-8 Discussion

.............................................................................................................................

2-9 3 LABORATORY STUDIES ON CRITICAL THERMAL LIMITS ...............................................

3-1 Introduction

.........................................................................................................................

3-1 M ethods ...............................................................................................................................

3-2 Fish Collection and Care ............................................................

3-2 Gradual Cold Shock and Subsequent Recovery ............................................................

3-2 Instantaneous Cold Shock ...............................................................................................

3-2 Results-G izzard shad ............................................................................................................

3-3 Critical Therm al M inim um Determ ination and Recovery .................................................

3-3 Instantaneous Cold Shock ................................................................................................

3-3 Results-Threadfin shad ..........................................................................................................

3-4 Critical Therm al M inim um Determ ination and Recovery ..................................................

3-4 Discussion

.............................................................................................................................

3-5 4 ASSESSING COLD SHOCK EFFECTS THROUGH PERFORMANCE AND PHYSIO LO G ICAL RESPO NSE ................................................................................................

4-1 Introduction

............................................................................................................................

4-1 M ethods .................................................................................................................................

4-2 Fish Collection and Care ..................................................................................................

4-2 ix General M ethods ..............................................................................................................

4-2 Experiment

1. Effects of Cold Shock on Swimming Performance and Physiological C o n d itio n ..........................................................................................................................

4 -5 Experiment

2. Effects of Combined Cold Shock and Reduced Ration on Swimming Performance and Physiological Condition

........................................................................

4-7 R e s u lts ...................................................................................................................................

4 -7 Effects of Cold Shock on Swimming Performance and Physiological Condition

..............

4-7 G izzard Shad--........................................................................

...............................

4-7 Threadfin Shad-. ........................................................................................................

4-8 Repeated Treatments for both Species- ............................................................................

4-8 Effects of Combined Cold Shock and Reduced Ration on Swimming Performance and Physiological Condition

...........................................................................................

4-11 Gizzard Shad-. .........................................................................................................

4-11 Threadfin Shad-. .......................................................................................................

4-12 Repeated Treatm ents for both Species-.

..................................................................

4-12 Discussion

...........................................................................................................................

4-14 5 SUM M ARY ..............................................................................................................................

5-1 Sum m ary of Results .............................................................................................................

5-1 Future research needs ..........................................................................................................

5-3 6 LITERATURE CITED ..............................................................................................................

6-1 A APPENDIX ............................................................................................................................

A-1 X LIST OF FIGURES Figure 1-1. Total number of impinged fish (aliveand fresh dead) per season at 15 intake structures on the Ohio River (NOTE: the impingement data for fall 2005 included almost 1.1 million live but moribund threadfin shad collected at one power plant in a single day of sam pling) ...............................................

......................................................

1-3 Figure 2-1 Impingement of threadfin shad at Kingston Steam Plant and water temperatures at the intake canal from November 1976 through April 1977. (From: M cG e e et a l. 19 77) .............................................................................................................

2 -4 Figure 3-1 Time and temperature of LOE of 22 gizzard shad exposed to cold shock at a rate of 0.5 0 C/hr and acclimation temperature of 150C ..................................

3-3 Figure 3-2 Time of LOE and death for 10 gizzard shad acclimated to 15-°C then plunged into 4°C water bath for 24 hr and then warmed at room temperature over a 5-d p e rio d ... ............................................................................................................................

3 -4'Figure 3-3 Time and temperature of LOE of 20 threadfin shad exposed to cold shock at a rate of 0.5 0 C/hr and acclimation temperature of 150C ....................................................

3-5 Figure 4-1 Summary of the protocol used during cold shock and reduced ration experiments

.............................................................

4-3 Figure 4-2 Schematic of the swimming performance channel (top view) ...................................

4-5 Figure 4-3 Thermal scenarios tested (lines) with points of sampling for both threadfin shad (n=24 at each square) and gizzard shad (n=18 gizzard shad at each diamond).

Repeated trials are indicated by open circles ....................................................

4-6 Figure 4-4 Mean (+1 SE) swimming time, plasma cortisol, and plasma chloride of gizzard and threadfin shad exposed to cold shock treatment beginning at 150C and declining at a rate of 0.5 0 C/hr to the test temperature.

Gizzard shad were tested at 150C (control), 5°C, after 6 hr at 50C (50C Ext), 49C, and after 6 hr at 4°C (40C Ext).Threadfin shad were tested at 150C (control), 8.50C, 8.50C + 6 hr (8.50C Ext), 7.50C, and 7.50C + 3 hr (7.50C Ext). Treatments that are statistically different (P <0.05) have different letters ................................................................................................

4-9 Figure 4-5 Linear correlations of mean cortisol and mean chloride to mean swim time of gizzard and threadfin shad ...............................................................................................

4-10 Figure 4-6 Mean (+1 SE) swimming time, plasma cortisol, and plasma chloride of gizzard and threadfin shad exposed to cold shock after one of three protocols:

14 d of full ration, 14 d of reduced ration, or 21 d of reduced ration. Treatments that are statistically different (P<0.05) have different letters .....................................................

4-i3 Figure 4-7 Mean (+1 SE) condition factor, hematocrit, plasma total protein, and plasma triglycerides of gizzard and threadfin shad exposed to cold shock after one of three ration treatments:

14 d of full ration, 14d of reduced ration, or 21 d of reduced ration. Treatments that are statistically different (P<0.05) have different letters ..............

4-14 xi LIST OF TABLES Table 4-1 A comparison of several stress indicators (means) for original and repeated test groups of gizzard and threadfin shad. The 5°C test group (cold shock) and the 21 d test group (reduced ration and cold shock) were repeated with gizzard shad.The 8.5 0 C Ext test group (cold shock) and the 21 d test group (reduced ration and cold shock) were repeated with threadfin shad. Significant differences (P < 0.05)betw een m eans are indicated by asterisks

......................................................................

4-11 xiii INTRODUCTION As a result of concerns in the late 1960s and early 1970s over the potential effects of fish entrainment and impingement losses at electric generating facilities, Congress included §316(b)as part of the amendments to the Federal Water Pollution Control Act of 1972 (commonly referred to as the "Clean Water Act"). Under the Clean Water Act §316(b), an applicant for a National Pollutant Discharge Elimination System (NPDES) permit must demonstrate that the location, design, construction and capacity of its cooling water intake structure (CWIS)represents Best Technology Available (BTA) for minimizing adverse environmental impact.In 1995, the U.S. Environmental Protection Agency (USEPA) began a three-phased process to develop the rules related to §316(b).'

The final Phase I Rule, for new facilities, was published on 18 December 2001 (66 FR 65255) and was amended on 19 June 2003 (68 FR 36749). The final Phase II Rule, for existing electric generating facilities was published on 9 July 2004 (69 FR 41575). The Phase II Rule applies to existing facilities whose construction commenced prior to 17 January 2002 and that have cooling water intake structures with a design capacity greater than or equal to 50 million gallons per day (MGD), and use 25 % or more of the water withdrawn for cooling purposes.

The Phase III rule, for smaller (<50 MGD) power plants and certain industrial facilities, was published 16 June 2006 (71 FR 35005).USEPA's regulations establishing requirements for cooling water intake structures at Phase II existing facilities were challenged by industry and environmental stakeholders.

On judicial review, the Second Circuit decision (Riverkeeper, Inc. v. EPA, 475 F.3d 83, (2d Cir., 25 January 2007)) found some provisions illegal and remanded several provisions of the Phase II rule on various grounds. The provisions found illegal included the option to use restoration and cost-benefit analyses.

The key provisions remanded to EPA include: , EPA's determination of the BTA under §316(b);* the rule's performance standard ranges;" the cost-cost compliance alternative; and" the Technology Installation and Operation Plan provision In response to the decision, EPA suspended the Phase II rule on 9 July 2007 (72 FR 37107). In lieu of the suspended Phase 1I Rule EPA required that permitting authorities develop case-by-case, best professional judgment (BPJ) controls for existing facility cooling water intake structures that reflect the best technology available for minimizing adverse environmental

'Cronin v. Browner, No. 93 Civ. 0314 (AGS)(S.D.N.Y.), Order of 21 November 2000.1-1 Introduction impact. CWA provision 40 CFR 125.90(b) directs permitting authorities to establish

§316(b)requirements on a BPJ basis for existing facilities not subject to categorical

§316(b) regulations.

Though remanded, it is anticipated that some features of the Phase II Rule related to technology-based performance standards will be retained when USEPA revises the rule in the future 2.The suspended Phase II Rule had established performance standards for cooling water intake structures that would have required substantial reductions in impingement mortality and entrainment relative to a Calculation Baseline.

The Calculation Baseline is the impingement mortality and entrainment that would hypothetically occur if the facility had a shoreline, near-surface intake, traveling screen with a standard 3/8 inch mesh with its face oriented parallel to the shoreline, but no other measures to reduce impingement mortality and entrainment.

Among other requirements, the remanded Phase II Rule had required a reduction of impingement mortality by 80 to 95% from the Calculation Baseline for all Phase II in-scope power plants in the U.S.The USEPA has recognized the need to evaluate naturally moribund fish and shellfish entering cooling water intake systems (USEPA 2006). For example, as part of the Verification Monitoring Plan for compliance alternatives in § 125.94(a)(2), (3), (4), or (5), an applicant proposal was to be submitted outlining how naturally moribund fish and shellfish entering the CWIS will be identified and used to meet performance standards in § 125.94(b).

Although the Verification Monitoring Plan is part of the remanded Phase II rule, it is reasonable to expect that permitting authorities will take into account the numbers of naturally dead and moribund fish entering the CWIS when evaluating the need for controls to minimize adverse impacts to fish populations.

In a letter regarding calculation baseline estimates at the Muscatine Power Plant (Iowa), EPA Region VII stated that "... moribund fish should not be counted in the impingement calculation baseline.

Sampling of impingement should count all fish, but moribund fish should not count toward the calculation baseline" (USEPA 2006).Many studies have demonstrated a relationship between increased power plant impingement and the incidence of natural mortality for several fish species, particularly for clupeid species (Griffith and Tomljanovich 1975; Loar et al. 1978; McLean et al. 1979; McLean et al. 1980;McLean et al. 1981; McLean et al. 1985; LaJeone and Monzingo 2000). However, field evaluations of the condition of fish (e.g., living, dead, moribund, recoverable) prior to impingement can be difficult and are rare. EPRI recently completed 3 a 2-yr survey of impingement at 15 power plants on the Ohio River. Of the 112 seasonally-combined events (8 seasons at 13 plants and 4 seasons at 2 plants), there were 16 seasonally-combined impingement events of more than 10,000 fish that occurred at 7 of the 15 plants. These 16 seasonally combined events included large numbers of gizzard shad (Dorosoma cepedianum; 13 seasonally-combined events), threadfin shad (Dorosoma petenense; 3), freshwater drum (Aplodinotus grunniens; 2), and skipjack herring (Alosa chrysochloris; 1).During these high seasonally-combined impingement events, 25% (average) of the impinged fish were alive at the time of sample collection.

In four of the seasonally-combined events living fish 2 USEPA began a revised rule-making effort in the fall of 2007 and tentatively plan on releasing a draft revised Phase HI Rule in late 2008 or early 2009. Also of note is that the 2'" Circuit Court decision of 2007 has been appealed to the U.S. Supreme Court for review.3 Ohio River Ecological Research Program: Impingement Mortality Characterization Study at 15 Phase II Generating Stations.

EPRI Draft Report, January 2008. Final report planned for June 2008.1-2 Introduction comprised less than 1% of the impingement counts for the predominant species. Nearly all of the fresh dead fish (i.e., those that had recently died or perhaps moribund) were captured during fall and winter samples (Figure 1-1). Studies at the Muscatine Plant (Iowa) found that more than 95% of fish entrapped on barrier nets in December (357 total fish) and February (961 total fish)were either moribund or dead (HDR LMS 2006).1,200, ..........

..0.................................................................................

0--- Fresh dead I -U- Alive 1,000,000..........

I \I \800,000 ...........................

I \I \600,000..................................

I\400,000........I.........................

200,000 -0 Sum05 Fall05 W05/06 Sp06 SumO6 FalI06 W06/07 Sp07 Figure 1-1 Total number of impinged fish (alive and fresh dead) per season at 15 intake structures on the Ohio River (NOTE: the impingement data for fall 2005 included almost 1.1 million live but moribund threadfin shad collected at one power plant in a single day of sampling).

Laboratory studies designed to better understand the factors that contribute to fish impingement are necessary to assign project responsibility and adjust fish protection technology performance accordingly.

For example, information on the behavior and physiological state of cold-stressed fish prior to impingement may help industry, regulatory, and resource agencies determine the proportions of impinged fish that were already dead or dying when they entered the CWIS.Further, if used as a monitoring tool, behavioral or physiological indicators may be valuable for predicting the environmental conditions and/or fish population dynamics under which large impingement episodes will occur. This knowledge would enable utilities to adjust the operations of their power plants to reduce the loss of debilitated, but recoverable, fish as well as prevent blockage of cooling water flow.Cold shock and starvation have been proposed as primary causes of winter mortality for many species including gizzard shad. White et al. (1986) conducted an extensive study on the physiological and biochemical responses of cold-shocked gizzard shad relative to susceptibility to impingement.

They found that even though lipid reserves are relatively high in gizzard shad going into winter, they have trouble mobilizing this energy reserve when temperatures are very cold and thus go in to a starvation mode even though they contain high fat reserves.

This results in a quick utilization of liver and muscle glycogens, which in turn results in other tissues being utilized for energy. In severe cases, liver function declines -and failure of other physiological functions often follows. For example, cell membranes begun to lose their ability to transport 1-3 Introduction materials properly which can result in poor energy delivery to the brain and subsequent brain dysfunction.

Loss of brain function results first in disorientation and eventually a comatose condition like that seen during winter mortality events. White et al. (1986) concluded that poor over-winter survival of gizzard shad in Sandusky Bay (Ohio) is a result of enzymatic acclimation occurring too late in the season causing eventual physiological failure.The purpose of this report is to present the results of two efforts by funded by EPRI to better.understand the condition of fish that become impinged at CWIS and the environmental conditions associated with impingement events. The first study, presented in Chapter 2, was a literature review of natural mortality events in clupeid fishes (i.e., shad, menhaden, and herring species).

By understanding the conditions under which natural events occur, resource managers and project operators can more accurately assess the contribution of natural causes to impingement at CWIS.The second study, presented in Chapters 3 and 4, was a series of laboratory experiments with gizzard shad and threadfin shad under different cold shock thermal regimes and feeding history designed to better understand the relationships among cold shock, nutritional status, and susceptibility to impingement.

These studies were intended to further the understanding of these relationships as reported by White et al. (1986) and others.This report is planned as a technical support document providing information and ideas that*EPRI members can use when discussing impingement compliance options with permitting agencies in areas where there are occurrences of high episodic natural mortality.

The information presented in this report will help establish guidelines for identifying the time of year and temperature dynamics that are likely to result in high incidences of naturally moribund and dead fish in CWIS impingement samples.As part of its corporate objectives to provide scientifically sound information for development of cost-effective environmental policies and regulations as well as information for cost-effective and scientifically sound compliance efforts, EPRI has supported a variety of studies that evaluated scientific methodologies and summarized potential environmental effects of cooling water withdrawals.

These studies have done much to advance the current state-of-the-art for addressing issues related to §316(b). In addition to this document, other EPRI reports that provide information relevant to §316(b)-related compliance sampling include: Fish Protection at Cooling Water Intake Structures:

A Technical Reference Manual (EPRI Report 1014934, 2007)Effects of Fluctuating Temperatures on Fish Health and Survival (EPRI Report 1012545, 2007)Latent Impingement Mortality Assessment of the Geiger Multi-DiscTM Screening System at the Potomac River Generating Station (EPRI Report 1013065, 2007)Technical Resource Document for Modified Ristroph Traveling Screens: Design and Construction Technology Plan and Technology Installation and Operation Plan (EPRI Report 1013308, 2006)1-4 Introduction Laboratory Evaluation of Modified Ristroph Traveling Screens for Protecting Fish at Cooling Water Intakes (EPRI Report 1003238, 2006)Design Considerations and Specifications for Fish Barrier Net Deployment at Cooling Water Intake Structures (EPRI Report 1013309, 2006)Field Evaluation of Wedgewire.

Screens for Protecting Early Life Stages of Fish at Cooling Water Intake Structures:

Chesapeake Bay Studies (EPRI Report 1002542, 2006)Field Evaluation of Wedgewire Screens for Protecting Early Life Stages of Fish at Cooling Water Intakes (EPRI Report 1010112, 2005)Impingement and Entrainment Survival Studies Technical Support Document (EPRI Report 1011278, 2005).Entrainment Abundance Monitoring Technical Support Document (EPRI Report 1011280, 2005)Impingement Abundance Monitoring Technical Support Document (EPRI Report 1008470, 2004)Parameter Development for Equivalent Adult and Production Foregone Models (EPRI Report 1008832, 2005)Extrapolating Impingement and Entrainment Losses to Equivalent Adults and Production Foregone (EPRI Report 1008471, 2004)Impacts of Volumetric Flow Rate of Water Intakes on Fish Populations and Communities (EPRI Report 1005178, 2003)Evaluating the Effects of Power Plants on Aquatic Communities:

Summary of Impingement Survival Studies (EPRI Report 1007821, 2003)Evaluating the Effects of Power Plants on Aquatic Communities:

Guidelines for Selection of Assessment Methods (EPRI Report 1005176, 2002)Evaluating the Effects of Power Plant Operations on Aquatic Communities:

An Ecological Risk Assessment Framework for §316(b) Determinations (EPRI Report 1005337, 2002)Technical Evaluation of the Utility of Intake Approach Velocity as an Indicator of Potential Adverse Environmental Impact under Clean Water Act Section 316 (EPRI Report 1000731, 2001)Review of Entrainment Survival Studies: 1970-2000 (EPRI Report 1000757, 2000)Taken together these documents provide utility managers, regulators, and interested parties technically sound guidance for the §316(b) determination process. It is EPRI's intent that these 1-5 Introduction documents be accepted as objective resources by a diversity of users involved in the regulatory process, including scientists, engineers, managers, and lawyers working for the utility industry, regulatory and resource management agencies, academic and private consultants, and environmental advocates.

1-6 2 NATURAL MORTALITY EVENTS IN CLUPEID FISHES: A LITERATURE REVIEW Introduction The family Clupeidae includes a wide diversity of prolific species, including blueback herring (Alosa aestivalis), alewife (Alosa pseudoharengus), American shad (Alosa sapidissima), gizzard shad and threadfin shad. Many clupeid species have been introduced into lakes and reservoirs as a forage base for recreationally important game species. Under optimal environmental conditions and low predator pressures, clupeid populations can expand quickly. For example, in the mid-1950s, about 1,000 threadfin shad were introduced into Havasu Reservoir, Colorado, and within one year the population numbered in the millions and had spread downstream of the reservoir (Moyle 2002). Large populations without controls can quickly exceed carrying capacity for the water body, resulting in mass mortality from starvation and disease. Studies have shown correlations between clupeid density and juvenile mortality for species like gizzard shad (Stock 1971; Kampa 1984; Buynak et al. 1992; Welker et al. 1994). Owing to their large numbers, clupeids often comprise a large proportion of the fish that are impinged at CWIS (Loar et al.1978).Many introduced clupeids have narrow thermal and water quality tolerance ranges, causing mass mortality during harsh periods. Sudden and drastic changes in temperature cause behavioral and physiological changes in many clupeid species. A rapid drop in temperature can cause loss of swimming and schooling abilities and a decrease in feeding (Griffith and Tomljanovich 1975).At temperatures near their lower tolerance limits, clupeids experience loss of equilibrium, erratic swimming, movement to the surface, and lack of response to external stimuli (Griffith 1978).These behavioral changes not only make clupeids vulnerable to predation, but they can become more susceptible to power plant impingement.

Rapid decreases in watertemperature can occur naturally, or as a result of plant operations.

The winter shutdown of industrial facilities that produce warmwater discharges can cause debilitating or lethal cold shock among clupeids that congregate near these warmwater discharges during winter (Burton et al. 1979).This chapter presents the results of a literature search and review to address the relationship between the occurrences of naturally stressed and moribund fish and impingement at CWIS. This literature review focused on five members of the herring family (Clupeidae)

-threadfin shad, gizzard shad, alewife, Atlantic menhaden (Brevoortia tyrannus), and Gulf menhaden (Brevoortia patronus).

Each of these five species have a documented history of large scale die-offs, represent a significant component of impingement at cooling water intake structures, and are found over a broad geographic range encompassing fresh, brackish and marine waters. Specific objectives of the review were to identify and summarize available information for the species listed above related to each of the following areas: 2-1 Natural Mortality Events in Clupeid Fishes: A Literature Review" Susceptibility of each species to die-offs;* Seasonality of such die-offs;* Contributing environmental conditions and other causal factors (i.e., stressors);" Physiological processes and indicators of stressor exposure;* Relationship to cooling water intake impingement; and,* Recorded occurrences of large-scale die-offs, including species and geographic locations.

The search for information was conducted in five phases. First, literature contained within library holdings at ASA Analysis & Communication, Inc. relevant to §316(b) issues were identified and accessed.

Second, a thorough search of the Internet was conducted for relevant information.

Third, a broad-based search was conducted through the Dialog system. This search focused on three databases:

Biosis Previews, National Technical Information Service (NTIS), and the Electric Power Database.

A broad search of these databases yielded over 1,100 relevant titles.The full record, including the abstract, was printed and used to identify the most useful and r levant literature.

Fourth, the reference lists in all of the literature identified in.phases 1.- 3 of the search were reviewed to identify additional materials.

Finally, individuals with prior research experience in areas related to fish impingement and §316(b) issues were contacted to obtain additional, often unpublished, reports and papers.Seventy three relevant reports and published reference materials were identified and retrieved as part of this effort. An annotated listing of these materials is provided in Appendix A and is summarized by species below.Threadfin shad Threadfin shad is one of the most important forage species in many water bodies, especially in Southeastern lakes and reservoirs (Schael et al. 1995). In these water bodies, this species often provides an important source of food for largemouth bass (Micropterus salmoides), channel catfish (Ictalurus punctatus), and striped bass (Morone saxatillis).

As a result of its importance as a forage species for many recreationally important fish species, threadfin shad have been introduced over wide geographic areas of the country. However, threadfin shad are a short-lived, fragile fish prone to frequent die-offs when conditions are sub-optimal (Higginbotham 1988). For example, threadfin shad are known to suffer mass mortality when water temperatures fall below 5-6°C. In addition, this species is sensitive to dissolved oxygen depletion during summer months and can exhibit large die-offs after spawning as a result of cumulative physiological stress. The reduced physiological condition of threadfin shad during summer months is believed to have increased impingement at the Comanche Peak Steam Electric Station in Texas from 1993 through 1994 (TUEC 1994). During the period from late July to late August when water temperatures were at their highest, 81 % of the annual impingement of threadfin shad occurred at this station.While it appears that threadfin shad can be susceptible to a wide variety of stressors, temperature appears to be the primary contributor to most large-scale mortality events. Griffith (1978) found that threadfin shad started dying at 9°C and that none of his study fish survived at 4°C. In 2-2 Natural Mortality Events in Clupeid Fishes: A Literature Review addition, threadfin shad mortality can be high when they are exposed to water temperatures at 9°C for several months (Strawn 1965). A sudden drop in temperature can not only cause detrimental behavioral changes and decreased feeding, but can also cause loss of equilibrium and death (Griffith 1978). Loss of equilibrium due to cold shock can cause hemorrhaging and fungal infections (Colby 1973). In fact, because of their sensitivity to low water temperatures, threadfin shad survival in some water bodies may require access to warm water discharges from power plants. For example, during a 1983 survey of the upper Mississippi River threadfin shad were only collected near the Portage Des Sioux power plant, and survival of threadfin shad in Montrose Lake, Missouri, is believed to be dependent on the warm water discharges from a steam generating plant (Pflieger 1997).Low temperatures also appear to be a primary factor affecting impingement rates at many cooling water intakes. This is a common occurrence for many Southern power plants, as threadfin shad impingement typically increases when water temperatures fall below 10'C (Loar et al. 1978). A study of 32 Southeastern United States power plants found that threadfin shad accounted for more than 90 % of all fish impinged, with peak impingement of thisspecies occurring in winter (Loar et al. 1978). Increased threadfin shad impingement occurred at the following power plants when water temperatures were below 15'C: Green River, Kentucky;Allen, North Carolina; Marshall, North Carolina, Riverbend, North Carolina; Arkansas One, Arkansas; Oconee, South Carolina; Wateree, South Carolina; and Eagle Mountain, Texas.Impingement of large numbers of threadfin shad at Kingston Station, Tennessee, coincides with threadfin shad die-offs in the reservoir on which this steam electric power plan is located (McGee et al. 1977; McLean et al. 1985). The highest densities of impinged threadfin shad coincided with a sudden drop in water temperature (Figure 2-1). Impingement of threadfin shad at Kingston Station increased to 5,000 shad per day in December when temperatures dropped to 7°C. As water temperatures continued to decrease to 4°C, 42,000 threadfin shad were impinged on 8 December (McLean et al. 1980).In years with mass mortality during severe winters, all age and size classes are affected and a majority of the threadfin shad population was eliminated (McLean.et al. 1985). However, this highly fecund and fast-growing species has the ability to rebound quickly in the years following a significant die-off. Fish which hatch in spring are capable of spawning that same summer, enabling a population to quickly rebound following mass mortality.

For example, an estimated 95% of the threadfin shad population was removed from Watts Bar Reservoir during the winters of 1976-1977 and 1977-1978 as a result of impingement mortality and winter kill. However, the threadfin shad population had rebounded by autumn of each year following the die-offs (McLean et al. 1980).2-3 Natural Mortality Events in Clupeid Fishes: A Literature Review lbj 20 -16 IMPINGEMENT 16 C3 0U')co LU a.16 a LU TEMPERATURE 9 12 --8 U. -_" U_ z w ,.j LU LUj 4 0 0-NOV DEC JAN FEB MAR APR Figure 2-1 Impingement of threadfin shad at Kingston Steam Plant and water temperatures at the intake canal from November 1976 through April 1977. (From: McGee et al. 1977).The following reports provide details of documented mass mortality events of threadfin shad: Watts Barr Reservoir, Tennessee 1976-1977

-Mass threadfin shad mortality due to a severe winter (McLean et al. 1985)Pee Dee River, North Carolina May 2002 (NCDWQ 2002)Sacramento

-San Joaquin Delta, California

-Mass die-off during winters when temperatures drop to 6-8°C (Moyle 2002)Clear Lake, California

-Extirpated during severe winter of 1990-1991 (Moyle 2002)White River Basin, Missouri -Occasional massive winter mortality (Pflieger 1997)2-4 Natural Mortality Events in Clupeid Fishes: A Literature Review Lake Texoma, OK 2001 -Severe winter kill in mid-February 2001 (OK Department of Wildlife Conservation 2001)Bull Shoals Reservoir, Arkansas 1983-1984-Severe winter kill (Arkansas Game and Fish Commission 1995)Norfolk Lake, Arkansas 1996 -Severe winter kill (Arkansas Game and Fish Commission 1997)Smith Mountain Lake, Virginia 2002-2003

-Nearly complete die-off of population due to severe winter (Virginia Department of Game and Inland Fisheries 2004)Gizzard Shad Gizzard shad are native to most Southeastern states, but have since been introduced throughout much of the country (Cooper 1983; Kirtland 1844, cited in HDR LMS 2006). Introduced as a forage base for game species, gizzard shad, unfortunately, often outgrow their predators and quickly overpopulate a system. In many systems, gizzard shad are viewed as a nuisance fish as a-result of an .overpopulation of large adult fish. In addition, gizzard shad can compete with juvenile predators and other planktivorous fishes leading to declines in sport and native fish communities (Johnson et al. 1988; Michaletz 1997).Overpopulations of gizzard shad combined with severe winters and low dissolved oxygen often lead to mass mortalities.

Typically, mass gizzard shad mortalities tend to occur in the northern part of their range as a result of severe winters. For example, Kirtland (1844, cited in HDR LMS 2006) reported heavy winter kills of gizzard shad in the Ohio River, and White (1986) described the winter kills as being density dependent.

Gizzard shad larvae and juvenile survival has been correlated with water temperature in several midwest reservoirs; early cohorts not only grew slower as a result of lower temperatures, but also suffered higher mortalities than later age classes (Michaletz 1997). Winter die-offs are often more severe for younger age classes, as they typically deplete energy reserves more rapidly than do larger gizzard shad (Shuter and Post 1990). In addition, gizzard shad which are spawned later in the year have less time to build-up fat reserves (White et al. 1986). For example, during severe winters in Sandusky Bay, Lake Erie 100% mortality has been recorded for young-of-the-year (YOY) gizzard shad in the 40-85 mm size range and 99.9 % mortality for YOY between 90-140 mm (White et al. 1986). In other studies on Lake Erie, gizzard shad populations exhibited a shift in size range of YOY fish from mid-autumn through early spring. Because growth does not occur during this period, this shift in mean length and length range has been attributed to size selective mortality, over the winter (Caroots 1976).Similarly, high gizzard shad impingement counts at the Muscatine Plant in Iowa were initially dominated by YOY fish; later in the winter, the mean size of impinged shad increased (HDR.LMS 2006). Gizzard shad often dominate fish biomass in many bodies of water and can consume all of the food resources that might otherwise be available to other fish species. For example, higher gizzard shad levels can yield reduced growth in bluegills (Michaletz 1998). This reduced bluegill growth can lead to reduced growth in largemouth bass which preferentially feed on bluegills.

2-5 Natural Mortality Events in Clupeid Fishes: A Literature Review Periods of higher impingement rates for gizzard shad often correspond with periods of large winter die-offs; further, the size range of impinged gizzard shad also tends to overlap with size ranges of those fish subject to winter mortality.

For example, gizzard shad impinged from 1979 through 1984 at Eastlake, Avon Lake, and Edgewater generating facilities located in Lake Erie's Central Basin comprised mainly YOY fish in the 40-125 mm size range, similar to the size of fish which exhibited natural mortality (White et al. 1986).Gizzard shad are most susceptible to winter die-offs in the northern part of their range, as they are not physiologically adapted for survival during extended cold periods. Gizzard shad begin showing signs of disorientation when water temperatures are around 6 or 7°C (Cox and Coutant 1975). Gizzard shad rely on stored lipid reserves during the winter months, as feeding stops when water temperature declines to around 11 C, but level of activity remains unchanged (White et al. 1986). In addition, when water temperatures drop below 8VC, gizzard shad are unable to mobilize fat reserves and begin utilizing liver, muscle glycogens, and other tissues as sources of energy even though lipids remain. As the liver is metabolized, liver function begins to fail causing jaundice' In cold water, gizzard shad lose cell function and are unable to diffuse waste and materials across cell membranes.

After several weeks of these stressful conditions, gizzard shad begin to lose brain function which results in loss of equilibrium, erratic swimming, and finally ends in a comatose state and death (White et al. 1986).The following reports provide details of documented mass mortality events for gizzard shad: Several East Tennessee Reservoirs Spring 1983 -Large gizzard shad die-offs due to cumulative stresses and low lipid reserves (Adams et al. 1985)Sandusky Bay, Lake Erie -Mortality of 5 million gizzard shad per acre (White et al. 1986)Ohio River near Cincinnati, Ohio 1844 -Large winter kill (Kirtland 1844)Buckeye Lake, Ohio 1928 and 1940 -Winter die-off after cold snap; gizzard shad struggling at surface (Trautman 1928; Trautman 1940)Lewis and Clark Lake, South Dakota -100 % mortality of age Q+ age class after 103 days of ice cover (Walburg 1964)Western Basin Lake Erie 1955 -winter kill after cold snap; erratic swimming behavior (Bodola 1955)Huron River, Ohio 1982 -Die-off of millions of yearling gizzard shad after cold snap in weather (Cleveland Plain Dealer 1982)Acton Lake, Ohio -Complete mortality of age 0+ age class (Hiohowskyj 1983)Elephant Butte Lake,. New Mexico (Jester and Jensen 1972) and Presque Isle Bay. PA (Neumann et al. 1977) -large winter kill 2-6 Natural Mortality Events in Clupeid Fishes: A Literature Review Nebraska Lakes -Winds breaking down stratification causing deep waters to cool rapidly from 4°C to 0°C which caused mortality in gizzard shad (Heidinger 1983)Alewife Alewife have been introduced both purposely and accidentally into many northern lakes, such as the Great Lakes, and serve as a forage base for native and introduced salmonids and walleye.Although the alewife has lower thermal tolerances than other clupeids, such as threadfin shad, seasonal die-offs are common in land-locked populations.

In Lake Ontario and Lake Michigan, large seasonal alewife die-offs occurred in the 1960s and 1970s following severe winters (O'Gorman and Schneider 1986; Flath and Diana 1985).As a result of introductions of Pacific salmon and the revitalized lake trout (Salvelinus namaycush) and walleye (Stizostedion vitreurn) stocks, the alewife is a vital link in the food chain of the Great Lakes. In the 1960's, Lake Michigan alewife experienced an average yearly mortality rate of 68 % which Was attributed to winterkill and spawning stresses (Brown 1968).These large die-offs in Lake Michigan are thought to be an indirect result of competition leading to a reduction in fat reserves (Brown 1972). Annual die-offs in Lake Michigan correlated with the time of year in which energy reserves are lowest, an indication of insufficient feeding due to environmental stresses, competition, or a reduced plankton population (Flath and Diana 1985).As a result of population declines in several of the Great Lakes, large alewife die-offs are no longer a common occurrence; poor recruitment following the severe winters of 1976-1982 are believed to be the primary cause of Lake Michigan alewife declines (Eck and Wells 1987).Sudden exposure to warmer temperatures in littoral areas may also cause spring and early summer die-offs in alewife populations (McCauley and Binkowski 1982). Alewife may succumb to warm inshore waters after prolonged exposure to cold temperatures during harsh winters which deplete fat reserves (Colby 1973). The large die-offs in Lake Michigan in June and early July 1967 are believed to be a result of fish encountering warm littoral water as they moved inshore from deep cold water. This theory is supported by the fact that fish appeared robust, many contained rapidly digestible zooplankton, and all size classes of male and female alewife were affected (Brown 1968). Studies have indicated the upper lethal temperature for alewife is 25°C (McCauley and Binkowski 1982). Seasonal percent lipids stored by alewife from Lake Michigan are typically at their lowest (3-5 %) in late spring and early summer (Flath and Diana 1985).A severe winter in 1992-1993 in Lake Ontario was believed to have severely stressed the alewife population, causing a winter kill; many alewives remained in the littoral areas after spawning instead of moving to deeper water, which increased their vulnerability to impingement (Ross et al. 1996). A sound deterrent system used at James A. Fitzpatrick Nuclear Power Plant during this period exhibited decreased effectiveness when water temperatures were below 13'C, as a result of a diminished response of fish (Ross et al. 1996). Although severe winters can greatly reduce alewife populations, high fecundity and high early life stage survival allow alewife populations to quicklyrecover in 1 to 2 years (Brown 1972; Kohler and Ney 1981).The following reports provide details of documented mass mortality events for alewife: 2-7 Natural Mortality Events in Clupeid Fishes: A Literature Review Lake Michigan June and July 1967 -Large alewife die-off, tpossible temperature shock or algal toxicity (Stanley and Colby 1971; Brown 1968)Lake Michigan Early 1980s -Large decline in alewife population (Eck and Wells 1987)Lake Ontario, New York Spring 1993 -Highest mortality in 10 years (Schneider and Schaner 1994)Lake Ontario, New York -Alewife winter kill (O'Gorman and Schneider 1986; Bergstedt and O'Gorman 1989)Lake Michigan and Lake Ontario -Alewife mass mortality mainly in spring (Pritchard 1929;Graham 1956; Smith 1968)Lake Michigan 1960s -68 % average yearly mortality (Brown 1968)Claytor Lake, Virginia 1977-1978

-Large alewife die-off associated with severe winter (Kohler and Ney 1981)Lake Wononskopomuc, Connecticut

-Alewife die-off (Warshaw 1972)Atlantic & Gulf Menhaden Both species of menhaden are found in marine and brackish waters along the Atlantic .and Gulf coasts. Atlantic menhaden are found from Western Nova Scotia to Florida, while the Gulf menhaden occurs from Cape Sable, Florida, to Veracruz, Mexico. Both species serve as important forage for a variety of larger aquatic predators and also, as adults, support important commercial fisheries in certain regions. While most examples of significant mortality events have been reported for Atlantic menhaden, it is reasonable to expect similar events in the closely related Gulf menhaden.Menhaden mass mortalities appear to be less influenced by temperature stresses and more commonly caused by disease and overcrowding.

For example, the interactions of large populations of menhaden with predatory fish can promote large fish kills, as predators like bluefish and striped bass pursue schools of menhaden into small coves. These overcrowded menhaden schools quickly deplete dissolved oxygen concentrations in the small embayments, leading to anoxic conditions and large menhaden kills (ASMFC 2001). For example, a school of Atlantic menhaden near Core.Banks, North Carolina in 1997 was estimated to have a biomass of 60,000 million tons, with fish 9 m deep in the water column. This large concentration of fish is believed to have led to oxygen depletion and a large kill (Smith 1999). Oviatt et al. (1972)reported that dissolved oxygen concentrations within small schools of Atlantic menhaden were depleted by 12 % compared to the concentrations in water outside of the school.In addition to the effects of temporary anoxia, Atlantic.

menhaden mortalities have been reported in numerous estuaries along the East Coast as a result of ulcerative mycosis disease and toxic dinoflagellates (Ahrenholz et al. 1987; Noga et al. 1991; Burkholder et al. 1992; Faisal and Hargis 1992). Sudden decreases in water temperature as a result of winter shutdown at large 2-8 Natural Mortality Events in Clupeid Fishes: A Literature Review power plants can cause Atlantic menhaden mortalities.

For example, a temperature decrease from 15 to 5°C'caused all menhaden to die within 36 hr in laboratory studies (Burton et al. 1979).Details of Atlantic menhaden mass mortalities are provided in the following reports: Pamlico River, North Carolina May 2002 -.Increasing water temperature and changes in dissolved oxygen may have caused fish kill (NCDWQ 2002)Alligator Creek, North Carolina April 2002 -Shallow creek, no explanation for large kill (NCDWQ 2002)Neuse River, North Carolina July 2002 -High water temperatures and low dissolved oxygen.(NCDWQ 2002)New York Harbor -Annual die-off of millions of menhaden (Westman and Nigrelli 1955)Chesapeake Bay -Annual die-off caused by virus (spinning disease) (Stephens et al. 1980)Southern Maine 1980s & 1990s -Menhaden kills due to oxygen depletion in coves (Vaughan 1990; Conniff 1992)East Coast Estuaries

-Kills caused by toxic dinoflagellates (Ahrenholz et al. 1987;Sindermann 1988; Noga et al. 1991; Burkholder et al. 1992; Faisal and Hargis 1992)Core Banks, North Carolina 1997 -School induced low dissolved oxygen concentrations (Smith 1999)Oyster Creek Nuclear Generating Station, NJ 1972, 1973, 1974, 1975 -Menhaden kills likely a result of cold shock (Coutant 1977)Discussion Based on the summarized literature, reports of mass mortalities of clupeids are quite common, especially in larger freshwater lakes, rivers and reservoirs, and brackish and marine embayments.

However, to date, studies of the causes of this mortality as well as the general physiological responses of clupeids to potential environmental stressors have been limited. This lack of published research often leaves fisheries managers guessing at the causes of mass mortality, how to prevent such occurrences, and how to predict large clupeid die-offs.Perhaps the most extensive research on the topic was conducted by White et al. (1986). These studies provide detailed information on the physiological response of gizzard shad to thermal stress and provide clues to link mass mortalities to cold stress, but it is unclear whether such information is relevant to other clupeids.

The authors found that the amount of stored lipids appears to play a role in determining winter kill of several clupeid species, but is not an effective means of determining cold stress mortality in gizzard shad, as gizzard shad are unable to utilize stored fat reserves below 8°C. At these low temperatures, gizzard shad begin metabolizing liver tissue and lose cellular function, which eventually leads to decreased liver and brain function..2-9 Natural Mortality Events in Clupeid Fishes: A Literature Review Necropsies of gizzard shad that died in cold stress-related mass mortality events revealed loss or breakdown of liver function, enlarged gallbladder, scale base hemorrhaging, jaundiced internal organs and eyes, and progressive darkening of bile.Unfortunately, details on menhaden, alewife, and threadfin shad mass mortality are not as well documented.

Alewife mass mortality was a common occurrence in the Great Lakes, Lake Huron, Lake Michigan, Lake Erie, and Lake Ontario. These die-offs seemed to be linked to severe winters, but since the introduction of predatory salmonids, mass mortality has not been as common an occurrence.

Alewife populations in several of the Great Lakes have been significantly reduced by poor recruitment following winterkill, predation by Pacific salmon and lake trout, or by competition with other planktivores and invasive dreissenid mussels, and coincidentally die-offs have not been as noticeable.

These observations suggest that mass winter mortality may be a density-dependent process. Research indicates the mass alewife mortalities which occurred in 198371984 were a result of poor condition in the alewife population, as temperatures were not as severe as previous winters (Bergstedt and O'Gorman 1989). In direct contrast, alewife collected prior to the severe winter of 1981-1982 were in good condition and, as a result, winter mortality was not severe (O'Gorman 1986). In contrast to gizzard shad energetics, fat reserves have been reported to play an important role in alewife survival during harsh winters and may be an effective tool for predicting mass die-off (Brown 1972; Colby 1973;Bergstedt and O'Gorman 1989).Based on documented occurrences, mass mortality of menhaden appears most likely to result from either a sudden change in water quality or disease. Menhaden often travel in large schools which have the ability to quickly degrade oxygen concentrations when confined in small areas.Theories of mass menhaden mortality include large schools being chased into small confined embayments by predators such as bluefish and striped bass. The respiration of several hundred thousand menhaden in a small area could quickly consume available dissolved oxygen, leading to asphyxiation.

Other sources of mass menhaden mortality include ulcerative mycosis disease, toxic dinoflagellates, and thermal shock as a result of power plant shutdown (Coutant 1977;Smith 1999).Although predicting mass mortalities is often difficult and problematic, identifying symptoms of cold shock in fishes is well documented.

Fish exposed to temperatures at or near lower tolerances exhibit a short period of increased swimming and hyperactivity, followed by decreased movements, a decrease in response, and finally loss of equilibrium, which is shortly followed by death (Coutant 1977). Cold stress in clupeids also leads to vulnerability to predation and power plant impingement.

Several Southeastern power plants have documented high threadfin shad impingement coinciding with a substantial drop in temperature and mass natural mortality (Griffith and Tomljanovich 1975; Loar et al. 1978; McLean et al. 1985). Laboratory studies suggest the uncoordinated swimming of cold-stressed threadfin shad prevents escape from power plant intake structures (Griffith and Tomljanovich 1975).2-10 3 LABORATORY STUDIES ON CRITICAL THERMAL LIMITS Introduction As noted in Chapter 2, high power plant impingement rates among clupeids have often coincided with observations of cold-stress-related reductions in swimming capabilities and mass mortalities in the nearby river and reservoir.

Recognizing that naturally cold-stressed and moribund fish may contribute to high impingement counts, it is important to quantify the effects of low temperatures on clupeid behavior, physiology, and mortality.

That is, to better understand the relationship between natural environmental conditions and impingement events we need a better understanding of the thermal tolerances of clupeids.One traditional approach to quantifying temperature tolerance (both minimum and maximum) of fishes is the critical thermal methodology (CTM). The critical minimum temperature (CTMin) is defined as the pre-death lower thermal point at which locomotion becomes disorganized and a fish loses the ability to escape from conditions which may ultimately lead to its death. This method usually involves exposing fish to a constant linear decrease in temperature until loss of equilibrium (LOE) or another endpoint is reached. The CTMin is typically defined as the median temperature at which individuals in a group of fish began to exhibit LOE. CTMin is species-specific and is a function of acclimation temperature (Beitinger et al. 2000; Brett 1956; Elliot 1981), acclimation time (Doudoroff 1942), and rate of temperature decline (Gunter and Hildebrand 1951). Fish acclimated to higher temperatures typically have a higher CTMin and, conversely, fish acclimated to low temperature may have a lower CTMin. The effect of rate of temperature decline on CTMin is not as straightforward.

It is generally accepted that, if the rate of decline is fast, there is little time for acclimation and the CTMin will be higher than at slower rates of decline where some acclimation occurs along the way. However, recent work with critical maximum temperatures suggest that slower rates of temperature increase can result in lowered CTMax because of a longer exposure time to temperatures above some threshold where thermal stress occurs (EPRI 2007). A similar relationship might also exist for CTMin.A range of temperatures causing general distress, loss of equilibrium, and mortality have been reported for gizzard and threadfm shad (Griffith and Tomljanovich 1975; Cox and Coutant 1976;Neumann et al. 1977; Griffith 1978; Heidinger 1983; McLean et al. 1985). The variability in methods and reported responses makes it difficult to assess the contribution of environmental conditions to impingement at cooling water intake structures.

The primary objective of this study was to determine the cold tolerance of gizzard and threadfin shad from a Tennessee reservoir during either gradual or immediate cold shock. A secondary objective that evolved during the study was to determine the ability of these species to recover after LOE.3-1 Laboratory Studies on Critical Thermal Limits Methods Fish Collection and Care Gizzard shad were collected in March 2006 and threadfin shad in September 2006 by electrofishing on the Clinch River, Tennessee.

Live shad were transported to Oak Ridge National Laboratory in 151-L barrels filled with ambient river water, equipped with aerators, and treated with 400 g of sodium chloride.

Shad were then held at 24°C for 3 to 5 d in 889-L circular tanks.Each tank was equipped with an aerator, and a constant 0.6 L/min flow through was maintained.

Shad were acclimated to feeding on frozen brine shrimp and laboratory conditions during this period. Following the 3-5 d acclimation, test fish were transferred to a 530-L rectangular tank, receiving 0.25 L/min of flow.Gradual Cold Shock and Subsequent Recovery Test groups of 22 gizzard shad (mean total length = 143 mm, weight = 24 g) or 20 threadfin shad (mean total length = 128 mm, weight = 17 g) were placed in a 530-L rectangular tank and acclimated for one weekat 15 +/- 0.2°C prior to testing. Each group was then subjected to a cold shock at a declining rate of 0.5°C/hr until LOE. Portable chillers paired with temperature controllers were used to regulate exposure temperatures within-+/- 0.2°C. As tank temperature dropped, the time and temperature at which LOE occurred was recorded.

Individuals within a test group exhibited LOE at different temperatures; we considered the CTMin to be the median temperature at which fish in a group lost equilibrium.

Half of the fish were randomly assigned a holding period of 30 min in the cold shock tank after losing equilibrium before being placed in a recovery tank. The other half of the test group was transferred immediately after LOE to one of 12 recovery aquaria (30.5 cm 3) within a larger tank, which was the same size as the cold shock tank. The larger tank was filled to a depth of 17.8 cm to serve as a water bath and maintained at the same temperature as the cold shock tank. The 12 recovery aquaria were filled to a depth of 17.8 cm and equipped with a water supply and aerator. Individual fish were placed into an aquarium and water was dripped into the aquarium at -25 mL/min to create a warming rate of about 1 .O 0 C/hr. The initial aquarium temperature, time of recovery, aquarium temperature at recovery, weight, and length were recorded for each fish. If individuals regained equilibrium for more than .1 5 min, recovery was noted.Instantaneous Cold Shock A test group of 20 gizzard shad (mean total length = 143 mm, weight = 24 g) were placed in a 530-L rectangular tank and acclimated for one week at 15 +/- 0.2°C prior to testing. Ten fish were plunged into a rectangular tank maintained at 4VC and another 10 fish into a tank maintained at 6°C. The tanks remained at these temperatures for the first 24 hr after which the tanks were allowed to warm at room temperature for the next 4 d. Time and temperature at which LOE occurred and recovery from LOE were recorded during the experiment if either occurred.3-2 Laboratory Studies on Critical Thermal Limits Results-Gizzard shad Critical Thermal Minimum Determination and Recovery Activity levels decreased as temperatures approached 5°C, and fish became totally lethargic by 4°C. Below 4VC there was little response to vibration in the water and capture by netting. The median LOE temperature for gizzard shad exposed to cold shock at 0.5°C/hr was 1.7°C and ranged from 1.0 to 2.7°C (Figure 3-1). All gizzard shad recovered as water warmed within recovery aquaria. On average, recovery occurred at 2.6°C, 0.8°C above the average LOE temperature.

Instantaneous Cold Shock Gizzard shad plunged into the 6°C water bath did not lose equilibrium or die during the 5 d of testing. The 10 fish plunged into the 4VC water bath all experienced LOE during the 5 d period (Figure 3-2). Within the first 15 min of being transferred from the holding tank to the 4VC water bath, 8 of 10 had lost equilibrium.

The remaining two fish experienced LOE during the 24-48 hr period. Two fish died on the third day of testing and one fish on the fourth day. The fact that the water warmed to 24°C (9°C higher than the acclimation temperature) during the recovery period may have, contributed to the three mortalities.

The seven remaining fish recovered (i.e., regained equilibrium) and survived the 5 d of testing.5 4 2~E 0 +-1300 1400 1500 1600 1700 Time (min)Figure 3-1 Time and temperature of LOE of 22 gizzard shad exposed to cold shock at a rate of 0.5°C/hr and acclimation temperature of 15'C.3-3 Laboratory Studies on Critical Thermal Limits 24 20 16.12 0)E-8 4-0 2 fish 4 C Cold Shock 7-d Acclimation LOE.... Death t 8 fish-1 0 1 2 Day 3 4 5 Figure 3-2 Time of LOE and death for 10 gizzard shad acclimated to 15 2 C then plunged into 4°C water bath for 24 hr and then warmed at room temperature over a 5-d period.Results-Threadfin shad Critical Thermal Minimum Determination and Recovery Several anecdotal signs of distress were observed in threadfin shad during the cold shock treatment.

Individuals began to swim out of sequence rather than in a school, often swimming into the side of the tank. Although the general activity level of these fish appeared to increase as temperatures decreased, there was little direct response to vibration and netting at 8.5°C. The median LOE temperature for threadfin shad exposed to cold shock at 0.5°C/hr was 4.8'C and ranged from 4.6 to 6.4'C (Figure 3-3). All threadfin shad recovered as water was warmed within the recovery aquaria. On average, recovery occurred at 7.5°C, 2.5'C above the average LOE temperature.

3-4 Laboratory Studies on Critical Thermal Limits LOE 0.4-5 ... ...............E I- Median LOE 4.B 0 C 4 3 1000 1200 1400 Time (min)Figure 3-3 Time and temperature of LOE of 20 threadfin shad exposed to cold shock at a rate of 0.5°C/hr and acclimation temperature of 15 0 C.Discussion The CTMin value we determined for gizzard shad is consistent with those reported by others, with one exception.

We found the CTMin for gizzard shad to be 1.7°C. Neumann et al. (1977)reported survival at temperatures below I°C for a short period, and Heidinger (1983) suggested that mortality occurs in gizzard shad at temperatures between 0 and 4VC. Cox and Coutant (1976) performed acute cold shock testing with gizzard shad acclimated at 15'C and reported a CTMin of 6°C whereas we observed no LOE at that temperature when applying similar methods.The CTMin values for gizzard shad exposed to gradual cold shock and instantaneous cold shock varied. Gizzard shad exposed to acute cold shock experienced LOE at 4 0 C whereas LOE did not begin to occur until 2.7°C undergradual cold shock. Some individuals did not lose equilibrium until 1 °C. Obviously, the rate of temperature change affects the CTMin of gizzard shad.We found the CTMin for threadfin shad to be 4.8°C. Griffith (1978) found CTMin values for threadfin shad between 4 and 6VC with mortality of the least tolerant at low temperatures as high as 9°C and 100 % mortality by 4 0 C. Similarly, McLean et al. (1985) reported impingement of threadfin shad increased significantly when water temperatures dropped below 7°C. Threadfin shad were not exposed to instantaneous drops in temperature, therefore the relationship is still unclear for this species. However, Griffith (1978) reported a CTMin similar to ours for threadfin shad using a rate of change of 1.0 0 C/hr compared to our 0.5°C/hr.Signs of behavioral distress during cold shock prior to LOE or death in threadfin shad have been reported by other investigators.

Griffith (1978) found that threadfin shad exposed to acute temperature declines began showing signs of behavioral distress as much as 5oC higher than 3-5

, Laboratory Studies on Critical Thermal Limits lethal temperature, and he observed a lack of response to movement and vibration at 6-7°C above lethal temperature.

Griffith and Tomijanovich (1975) reported moribund threadfin shad exposed to 1-4°C temperature declines in 4 hr swam individually rather than in schools prior to LOE. These observations are consistent with the anecdotal signs of distress in gizzard and threadfin shad we observed.Various acclimation temperatures were not tested to determine how the CTMin was affected for either species, although we know that CTMin generally declines with acclimation temperature to a point. Cox and Coutant (1976) reported that the timing of equilibrium loss for gizzard shad was.a function of exposure and acclimation temperature.

However, the variation in CTMin was less than 1 C at the three acclimation temperatures of 15, 17.5, and 20'C tested by Cox and Coutant (1976).Threadfin and gizzard shad that experienced LOE under the gradual cold'shock recovered when exposed to warmer water. We found 100 % survival regardless of the CTMin temperature for any given individual.

However, we did not monitor long term survival, and we declared recovery if equilibrium was regained for greater than 15 min. Griffith (1978) also reported threadfin shad were capable of recovery if placed into water 3.0°C above an individual's CTMin but survival was not 100 %; fish with the lowest temperature tolerance had greater survival.

The recovery ability of gizzard shad after reaching their CTMin has not been previously reported for comparison.

However, gizzard shad are the mor6 temperature tolerant species and would be expected to recover under colder conditions than threadfin shad.In summary, the CTMin of gizzard shad appears to be between 1.5 and 4°C depending on the acclimation temperature and possibly other factors. Rate of temperature decline is an important factor when determining the CTMin for gizzard shad. Acute temperature drops yielded CTMin values several degrees warmer than those resulting from gradual cold stress. This is important considering that many natural die-offs' are the result of strong cold fronts chilling water bodies quickly. Rates of change greater than 1.0°C/hr appear necessary to affect the CTMin of gizzard or threadfin shad. If water temperatures drop below 6°C, threadfin shad may begin to lose equilibrium, regardless of the rate of temperature decline. If temperatures drop below 3°C, gizzard shad may also become susceptible.

These values can be used to make general rules about assigning the relative role of natural mortality during winter impingement events. Power plant managers should monitor water temperatures in the vicinity of water intakes for these critical limits. If critically low ambient water temperatures are imminent, the impingement of threadfin and gizzard shad might be reduced by altering plant operations.

This study has shown the importance of differentiating between moribund, impaired, and unimpaired fish relative to susceptibility to impingement.

By definition, it is assumed that moribund fish would not recover and would die regardless of impingement, whereas impaired fish (such as those stressed by cold water temperatures in our experiment) would not necessarily die due to natural causes, but their condition may lead to death via impingement.

Similarly, impaired shad are more susceptible than healthy shad to natural predation.

As an analogy to natural predation, power plants could be considered selective predators that remove weak individuals from the population that would have been removed by natural predators.

Several studies have related cold shock to increased predation rates in fish (Coutant et al. 1974; Coutant et al. 1976; Wolters and Coutant 1976). Best professional judgment of the permitting authorities (or future USEPA regulations for Phase II facilities) will apparently allow the estimation of 3-6 Laboratory Studies on Critical Thermal Limits impingement losses to account for moribund fish (EPA 2006). However, further scientific evidence would be useful to clarify the natural environmental fate of shad impaired by cold shock.3-7 4.ASSESSING COLD SHOCK EFFECTS THROUGH PERFORMANCE AND PHYSIOLOGICAL RESPONSE Introduction In the NPDES permitting process for cooling water intake structures, best professional judgment of the permitting authorities (or future USEPA regulations for Phase II facilities) may allow the estimation of impingement losses to be corrected for moribund fish. Presently, moribund fish entering the intake are identified by observational or visual criteria.

However, observation of general fish behavior as an indicator of prior impairment may be misleading; cold-stressed shad may increase their activity level, even though swimming is impaired andsusceptibility to impingement is increased.

Quantification of other parameters, such as the fish's physiological state or particular components of its behavior, may be useful techniques for evaluating the influence of natural environmental conditions on impingement.

Impingement likely increases when shad are subjected to temperatures that affect their physiological function and performance.

Increased susceptibility to impingement occurs at some point above the LOE temperature for both gizzard shad and threadfin shad, and may be an ihdicator of natural mortality in the water body induced by cold shock. The premise for the studies reported in this chapter is that the level of acute and chronic cold stress prior to LOE can be quantified using physiological-bioindicators, and that these stress responses are related to moribundity.

The use of plasma cortisol and chloride to quantify sub-lethal stress responses in fish is well established (Barton et al. 2002, Strange and Schreck 1978). White et al. (1986) used plasma cortisol and chloride to quantify stress response to cold shock in gizzard shad. Reduced ration has also been shown to affect natural mortality in gizzard shad (Adams et al.1985).

Lipids are typically stored during periods of high food availability (summer and fall) and utilized during periods of low food availability or non-feeding periods (winter and early spring) (Adams 1999).The influence of feeding at cold temperatures and duration of starvation on susceptibility.

to impingement has not been investigated.

Bodola (1966) reported that gizzard shad discontinued feeding at I I°C. Both gizzard and threadfin shad are lethargic during cold periods, but the* energy demand to maintain physiological homeostasis continues, which requires the utilization of energy reserves if feeding has ceased. The physiological condition of fish, quantified using various bioindicators of nutrition, could reveal the role of ration in natural mortality.

Hematocrit, triglycerides, and total protein have been used as general indicators of nutrition and starvation in fish (Adams et al. 1985, 1992; Barton et al. 2002). The condition factor (K), an index that relates weight and length, reflects energy storage and metabolism due to starvation (Dutil et al. 2003).4-1 Assessing Cold Shock Effects through Performance and Physiological Response Swimming performance or endurance is a useful behavioral measurement for relating physiological condition to impingement.

Griffith and Tomljanovich (1975) used swimming performance to determine the ability of cold-shocked threadfin shad to avoid impingement and found high impingement mortality below 8°C. Martinez et al. (2004) demonstrated that starved Atlantic cod (Gadus morhua) exhibited a reduced swimming endurance compared to cod that had been fed. However, the combined effects of reduced ration and cold shock on swimming performance have not been investigated.

The challenge for environmental managers and regulators is to determine whether fish impinged on intake screens would have died anyway because of natural environmental conditions.

Bioassessment techniques can be used to reveal the effects of suboptimal environmental conditions on swimming performance and physiological state. When coupled with onsite observations of water temperatures, wind speed and direction, and fish condition, this performance and physiological response data may help explain the causes of impingement events,. To assist in assessing the causes of impingement, a bioassessment tool or simplified procedure is required that can quantify the stress condition of gizzard and threadfin shad as they become vulnerable to impingement.

In this regard, the primary objectives of this study were to: 1) identify the critical points where cold shock and reduced ration affect the ability of gizzard and threadfin shad to escape impingement and 2) identify physiological and performance indicators that may indicate increased susceptibility of gizzard and threadfin shad to impingement.

Methods Fish Collection and Care Gizzard and threadfin shad were collected by electrofishing from August to October 2005 on the Clinch River, Tennessee.

Water temperatures ranged from 20-28°C. Live shad were transported to Oak Ridge National Laboratory in 151-L barrels equipped with aerators and treated with 400 g of sodium chloride.

Shad were then held at 24°C for 3 to 5 days in 889-L circular tanks. Each tank was equipped with an aerator and a constant 0.6 L/min through-flow was maintained.

Shad were acclimated to feeding on frozen brine shrimp and laboratory conditions during this period.General Methods Following the 3-5 day acclimation, test fish were transferred to 530-L rectangular tanks receiving 0.25 L/min of flow in groups of either 34 gizzard shad (mean total length = 153 mm, weight = 30 g) or 45 threadfin shad (mean length = 134 mm, weight = 17 g) per tank. The number of individuals in each test group exceeded the number required for testing to allow for mortality during acclimation.

Portable refrigeration units paired with temperature controllers were used to regulate exposure temperatures within +/- 0.2°C. Each group was acclimated for one week at 15 +/-0.2°C prior to testing in one of two general treatments, either cold shock alone or a combination of reduced ration with cold shock. The protocol used for the two experiments is illustrated in Figure 4-1. A single test group for each experiment was repeated for each species.4-2 Assessing Cold Shock Effects through Performance and Physiological Response ACCLIMATION 15'C for 7 days -full ration".0 TREATMENTN'r

_______Cold Shock Cold Shock + Ration*0.50C/hr decrease -3 ration treatments-to 7.5 or 8.50C -full ration for 21 d (threadfin) -reduced ration for 14 d and -reduced ration for 21 d-to 4 or 50C then (gizzard)

-0.50C/hr decrease (fish sampled -to 8.50C (threadfin) immediately and after -to 50C (gizzard)extended exposure at (fish sampled immediate-each temperature) ly at each temperature)-N EFFECTS TESTING Cold Shock Cold Shock + Ration-Swim endurance -Swim endurance*2 blood parameters

-5 blood parameters Figure 4-1 Summary of the protocol used during cold shock and reduced ration experiments.

At the time of testing, 18 gizzard or 24 threadfin shad were removed from their exposure tanks for blood collection.

Shad were quickly removed from the exposure tanks with small dip nets to minimize handling stress and immediately anesthetized with tricaine methanesulfonate (MS-222). Three shad were removed at a time and bled within 2 to 4 min of being placed in MS-222.Fish were bled using 21G1 VacutainerTM needles paired with 13 X 75 mm heparinized KendallTM collection tubes. Total length (mm) and weight (g) were measured for each individual.

Within a test, blood samples were randomly pooled, due to the low volume of serum derived from individuals, to form 6 pooled groups of 3 gizzard or 4 threadfin shad for each treatment.

Threadfin shad were smaller than gizzard shad so more individuals were needed per pooled group, Hematocrit was measured for each pooled sample. Plasma was separated from whole blood by centrifugation, transferred to 1.5-mL cryotubes, and stored in liquid nitrogen until analysis.

Plasma cortisol concentration was determined via Coat-A-Count solid-phase 1251-cortisol radioimmunoassay.

Plasma chloride was determined using a spectrophotometric assay by Pointe Scientific T M.For swimming performance tests, 10 gizzard or threadfin shad were removed from treatment tanks (the same tanks from which the fish to be bled were taken) and placed into the corral area 4-3 Assessing Cold Shock Effects through Performance and Physiological Response of the swimming performance (test) channel (Figure 4-2). Thedimensions of the test channel and methods of the test allowed 5 fish to be tested simultaneously.

The test channel was maintained at the target temperature using portable refrigeration units. The flow (-0.15 m/s) in the test channel was produced by a 3/4 horsepower centrifugal pump. Water was pumped from the corral zone and introduced to the upper end of the test channel through a series of increasing-diameter pipes and a 0.32-cm mesh screen to even the flow distribution within the test zone of the channel. The performance test channel was 10.8 cm wide X 122 cm long. Water depth was held at 14.6 cm. The power to the pumpwas surged 3-4 times to allow the fish to orient upstream and gain swimming balance prior to initiating full flow velocity.Each individual was observed during a maximum period of I hr to determine if impingement occurred at the rear screen for > 15 s. Impinged fish were removed immediately, and total swim time (< 1 hr), total length (mm), and weight (g) of each individual were recorded.

Condition factor (weight / (length 3)

• 1000) was calculated for individuals.

Statistical analyses on all data were performed using SAS, version 9.1, and SPSS, version 14. A value of P < 0.05 was considered significant for all tests and simultaneous confidence was held at P = 0.05 for all post hoc tests. Correlations between variables were investigated using Pearson correlation coefficients.

Differences between test groups in swimming performance and physiological indicators were analyzed with analysis of variance (ANOVA). The Shapiro-Wilk statistic was used to test the assumption of normally distributed errors. If data were not normal, a natural log transformation of the dependent variable or ranked data was used in the ANOVA.Homogeneity of variance between treatments was assessed with Levene's test. If significant differences in mean values were indicated by the ANOVA F test, paired means were evaluated using the least significant difference (LSD) test. Dunnett's mean separation test for unequal group variances was used when heterogeneous group variances exceeded a 3-fold difference between any treatment pair (van Belle 2002).4-4 Assessing Cold Shock Effects through Performance and Physiological Response 2, t Scale (m)Chiller*0 0.5m Figure 4-2 Schematic of the swimming performance channel (top view).Experiment

1. Effects of Cold Shock on Swimming Performance and Physiological Condition The CTMin results reported in Chapter 3 were used to determine the cold shock treatment temperatures for the swimming performance and physiological state experiments (Fost 2006).Cold shock was induced by decreasing temperature at 0.5 0 C/hr starting at the acclimation temperature of 15'C and concluding at one of two target temperatures, either 4 or 5 0 C. We also 4-5 Assessing Cold Shock Effects through Performance and Physiological Response tested gizzard shad that were held for an additional 6 hr after reaching the target temperatures to determine the effect of extended or prolonged exposure at those temperatures.

We expected that extended exposure at a stressful temperature would either increase thelevel of thermal stress and be apparent in the bioindicators or, alternatively, provide some level of acclimation resulting in a less stressful response.

Figure 4-3 illustrates the four different thermal scenarios tested for each species (plus 15'C controls).

We repeated one treatment for each species to evaluate experiment repeatability and determine if any changes occurred over the period of time fish collections were being made. The 5°C gizzard shad test group was repeated 4 weeks after the initial tests, and results were compared to the initial test group of the same thermal regime.j C-E 16 14 12 10 8 6 4-o---Threadfin shad.. -- Gizzard shad-J 2 0 0" 5 10 15 20 25 30 Time (hr)Figure 4-3 Thermal scenarios tested (lines) with points of sampling for both threadfin shad (n=24 at each square) and gizzard shad (n=18 gizzard shad at each diamond).

Repeated trials are indicated by open circles.Cold shock experimentation with threadfin shad was the same as that for gizzard shad except that target temperatures were 7.50 and 8.5 0 C (Figure 4-3). Two groups of threadfin shad were held for extended exposure at 8.5°C (6 hr) and 7.5°C (3 hr) after the initial temperature decline. We repeated the 8.5°C extended treatment 3 weeks after the initial test and the results were averaged with the initial treatment used for comparison.

Controls for both species were sampled at the acclimation temperature of 15'C.Fish were monitored for abnormal behavior or signs of distress during the cold exposure.

Plasma cortisol (ng/mL) and chloride (mEq/L) levels in each pooled group were measured to determine acute stress response to the test temperatures.

Swim tests were also performed on the same pool of fish but not the same fish to determine if swimming performance was related to physiological condition.

Condition factor was calculated for each individual to determine if swimming performance was also correlated with condition.

4-6 Assessing Cold Shock Effects through Performance and Physiological Response Experiment

2. Effects of Combined Cold Shock and Reduced Ration on Swimming Performance and Physiological Condition Each test group was fed a reduced ration of 0.5 % of their mass in frozen brine shrimp for 14 and 21 days. Following these 14 and 21 d feeding periods, the control groups were fed 5 % of their mass in frozen brine shrimp for 14 days. Gizzard shad were cold shocked to a temperature of 5°C and threadfin shad to a temperature of 8.5'C at a rate of 0.5°C/hr from 15'C. The entire 21-day reduced ration group was repeated 24 hr after the initial for each species and the results were averaged with the initial treatments for comparison.

The test groups were observed for changes in swimming activity during the reduced ration period.Following the reduced ration period and cold shock treatment, blood was withdrawn, and total length (mm) and weight (g) were measured for each individual.

We measured plasma cortisol (ng/mL), chloride (mEq/L), total protein (mg/dL), triglycerides (mg/dL), and hematocrit

(%)level in each pooled group. Total protein and triglycerides were determined using a centrifugal fast analyzer (Cobas brand). A separate group of fish from the same treatment tank was tested for swimming endurance.

In March 2006 we collected additional fish from the field to determine if the nutritional status of laboratory shad after 14 or 21 days of reduced ration was similar to that found in fish collected from the reservoir.

in late winter.Results Effects of Cold Shock on Swimming Performance and Physiological Condition Gizzard Shad-* As in the experiments in Chapter 3, we observed signs of distress (abnormal behavior) during the gizzard shad cold shock treatments.

Activity levels decreased as temperatures approached 5°C and fish became totally lethargic (but upright) by 4°C. There was little startle response to vibration in the water and netting at 4°C.* In swimming performance tests, cold-shocked gizzard shad had significantly lower mean swimming times for all treatment groups than the control (P=0.005; Figure 4-4). Mean swimming time was less in gizzard shad cold shocked to 4VC than to 5°C. Swimming performance of gizzard shad in extended test groups (referred to henceforth as '4°C Ext' and'5°C Ext') was not different statistically from fish sampled immediately upon reaching the temperature, but the pattern of decreased endurance with increased exposure to cold was consistent with the overall trend." Mean condition factor was not different among test groups and there was no correlation between condition factor and mean swimming performance for gizzard shad.4-7 Assessing Cold Shock Effects through Performance and Physiological Response* Cold shock affected cortisol and chloride (P<0.001) levels in gizzard shad. Mean plasma cortisol and chloride were significantly higher in all cold shocked groups compared to controls (Figure 4-4). Mean plasma cortisol was highest for the two treatments at.4 0 C (the lowest temperature tested), but mean plasma chloride did not differ among cold shock treatments.

• There was not a significant correlation between swimming performance and either cortisol (R 2=0.62; p=O.11) or chloride (R 2=0.56; p=0.14; Figure 4-5).Threadfin Shad-* As in the experiments in Chapter 3, we observed signs of distress in threadfin shad during the cold shock treatments at temperatures 2-3°C above the LOE. Individuals began to swim out of sequence rather than in a school, often swimming into the side of the tank. The activity leyel of these fish appeared to increase as temperatures decreased.

There was little response to vibration and netting at 8.5°C and below.* Cold shock had a significant effect on swimming performance of threadfin shad (P<0.01).

As with gizzard shad, the results show a clear trend of decreasing swim endurance with increasing exposure to cold (Figure 4-4).* Mean condition factor did not differ among test groups, and, like gizzard shad, there was no correlation between condition factor and mean swimming performance for threadfin shad." Mean plasma cortisol was significantly lower in three of the four threadfin shad test groups compared to the control (P<0.001; Figure 4-4). Plasma cortisol levels for the 7.5°C Ext test group were significantly lower than those sampled immediately (Figure 4-4).* We found no correlation between swimming performance and cortisol (R 2=0.28; p=0.27) or chloride (R 2=0.0004; p=0.975; Figure 4-5). Mean plasma chloride was significantly different from the control for only two treatments, the 8.5'C Ext and the 7.5°C Ext (P<0.005; Figure 4-4). The 7.5°C test group had the lowest mean chloride among the test groups (Figure 4-4).Repeated Treatments for both Species-The gizzard shad repeated treatment did not differ from the initial group in swimming performance or mean chloride but did differ in mean cortisol (Table 4-1). The threadfin shad repeated treatment had a significantly longer mean swimming performance and lower mean cortisol compared to the initial group but no difference in mean chloride (Table 4-1).4-8 Assessing Cold Shock Effects through Performance and Physiological Response 70 ........................

......G .iz .z.ard -S h a.d .................

60 b 60 50 T b E 40 E 30 U) 20 C ct"0 " C 10 0C-4120 E ZM100 bc bc b-6 80i 2n a 60 -0 40-E S20 I. 0 98 b b b rr 96 T Threadfin Shad ..........................

a TI a b -b LU E b 0 a S92 0 E 90 88 ab b b T ac C Control 5°C 5°C Ext 4VC 4°C Ext Control 8.5°C 8.5°C Ext 7.5°C 7.5°C Ext Figure 4-4 Mean (+1 SE) swimming time, plasma cortisol, and plasma chloride of gizzard and threadfin shad exposed to cold shock treatment beginning at 15C and declining at a rate of 0.5°C/hr to the test temperature.

Gizzard shad were tested at 15'C (control), 5°C, after 6 hr at 5°C (5°C Ext), 4 0 C, and after 6 hr at 4VC (4°C Ext). Threadfin shad were tested at 15'C (control), 8.5°C, 8.5°C + 6 hr (8.5°C Ext), 7.5*C, and 7.5°C + 3 hr (7.5°C Ext). Treatments that are statistically different (P < 0.05) have different letters.4-9 Assessing Cold Shock Effects through Performance and Physiological Response W E E U, 80 70 60 50-40 30 20 10 Linear (Gizzard Shad)# Gizzard Shad 0 Threadfin Shad 0 0 0 0 0 20 40 60 80 100 120 Mean Cortisol (ng/ml)70 -60.-.50'E E 40 E 30 m 20 0 R2 = 0.56 0 0 10 I-I I 90 91 92 93 94 95 96 97 Mean Chloride (mEq/L)Figure 4-5 Linear correlations of mean cortisol and mean chloride to mean swim time of gizzard and threadfin shad.4-10 Assessing Cold Shock Effects through Performance and Physiological Response Table 4-1 A comparison of several stress indicators (means) for original and repeated test groups of gizzard and threadfin shad. The 5°C test group (cold shock) and the 21 d test group (reduced ration and cold shock) were repeated with gizzard shad. The 8.5°C Ext test group (cold shock) and the 21 d test group (reduced ration and cold shock) were repeated with threadfin shad. Significant differences (P < 0.05) between means are indicated by asterisks.

Dependent Variables Original Repeat P value (test group repeated)

Treatment Treatment Cold Shock Gizzard Shad (5°C test group)Swim Time (min) 42.33 43.60 0.9382 Cortisol (miEq/L) 88.60 69.52 <0.0001*Chloride (ng/ml) 95.92 93.90 0.0871 Threadfin Shad (8.5'C Ext test group)Swim Time 22.32 54.56 0.0049*Cortisol 42.63 21.64 0.0001*Chloride 94.28 94.25 0.9568 Reduced Ration + Cold Shock Gizzard Shad (21 d test group)Swim Time 60.00 37.85 0.0250*Cortisol 93.95 71.08 <0.0001*Chloride 96.50 96.23 0.8498 Total Protein (mg/Dl) 95.83 97.50 0.4605 Triglycerides (mg/Dl) 83.42 81.42 0.5877 Hematocrit

(%) 21.33 21.00 0.3960 Condition Factor 8.64 8.35 0.8743 Threadfin Shad (21 d test group)Swim Time 51.28 55.40 0.3722 Cortisol 44.54 50.51 0.0400*Chloride 93.42 91.44 .0.1453 Total Protein 70.00 72.50 0.1670 Triglycerides 27.00 45.08 0.0008*Hematocrit 15.67 16.00 0.2891 Condition Factor 7.24 7.21 0.1248 Effects of Combined Cold Shock and Reduced Ration on Swimming Performance and Physiological Condition Gizzard Shad-0 Gizzard shad generally remained active during the treatment periods (14 or 21 d) of reduced ration.4-11 Assessing Cold Shock Effects through Performance and Physiological Response" Groups fed a reduced ration did not have significantly different mean swimming performance after cold shock than fish fed a full ration (P=0.69; Figure 4-6). A treatment effect of reduced ration was observed for both cortisol and chloride (P<0.001)." Mean cortisol for the 14-d reduced ration group was higher than both the 21-d reduced ration group and control (Figure 4-6, Table 4-2).* Mean plasma chloride values for both reduced ration groups were lower than the control." Treatment effects were also observed in total protein (P<0.01), triglycerides (P<0.0001), and condition factor (P<0.01; Figure 4-7)..Mean plasma total protein was. significantly higher in the 21-d reduced-ration group than the 14-d reduced-ration group.* Mean plasma triglycerides decreased between 14 and 21 d of reduced ration." Mean condition factor was lower in the 21-d group than control." Gizzard shad collected in March of 2006 had lower mean condition (K=7.4) than fall-collected fish held in the laboratory for 21-d of reduced ration (K=8.1).Threadfin Shad-* Threadfin shad schooled and remained active during the reduced-ration test period.* Groups fed a reduced ration did not havesignificantly different swimming performance compared to controls (P=0.61; Figure 4-6).* Treatment effects were not found with cortisol (P=0.60) or chloride (P=0.08; Figure 4-6).* Treatment effects were observed for total protein (P=0.0001), triglycerides (P<0.0001), hematocrit (P<0.0001), and condition factor (P<0.01; Figure 4-7)." Total protein was significantly lower in the reduced ration groups, but there was no difference between the two reduced ration groups." Triglycerides were significantly higher in the 14-d reduced-ration group than controls and 21-d reduced-ration group.* Hematocrit was significantly lower in both reduced ration groups than the control with those held longest (21-d group) having the lowest hematocrit." Condition factor was lower in the 21-d reduced-ration group than the 14-d group or control, which were not different.

• As with gizzard shad, threadfin shad collected in March of 2006 had lower mean condition (K=6.7) than fall-collected fish after 21-d of reduced-ration (K=6.9).Repeated Treatments for both Species-Mean swimming performance and mean cortisol were significantly lower in the repeated 21-d reduced ration group of gizzard shad compared to the initial 21-day reduced ration group (Table 4-1). No other differences were found between the repeated and initial group of gizzard shad. Higher mean cortisol and lower mean triglycerides were the only differences between the repeated and initial 21-d reduced ration groups of threadfin shad.4-12 Assessing Cold Shock Effects through Performance and Physiological Response Gizzard Shad Threadfin Shad C E 60 50 40 30 20 10 0 a T1 aj-IUAFIU;140 120"j100 E- 80 E. 60 40 20 0 120 100". 80" 60 E 40 20 0 60 50 40 30 20 10 0 70 60 50 40 30 20 10 0 120 100 80 60 40 20 0 a a.y.a T Control 14 21 Days Days Control 14 21 Days Days Figure 4-6 Mean (+1 SE) swimming time, plasma cortisol, and plasma chloride of gizzard and threadfin shad exposed to cold shock after one of three protocols:

14 d of full ration, 14 d of reduced ration, or 21 d of reduced ration. Treatments that are statistically different (P<0.05) have different letters.4-13 Assessing Cold Shock Effects through Performance and Physiological Response 0 E-E EJ*0 120 100 80 60 40 20 0 Gizzard Shad a b a b IZU-j 0 c-E a)100 80 60 40 20 0 30 25 20 15 10 5 0 8.4 8.3 8.2 8.1 8 7.9 a a a a-b T Control 14 21 Days Days 100 80 60 40 20 0 90 75 60 45 30 15 0 30 25 20 15 10 5 0 7.1 7.05 7 6.95 6.9 6.85 6.8 Threadfin Shad a h h L-.0 LL 0 C-)a CI Control 14 21 Days Days Figure 4-7 Mean (+1 SE) condition factor, hematocrit, plasma total protein, and plasma triglycerides of gizzard and threadfin shad exposed to cold shock after one of three ration treatments:

14 d of full ration, 14 d of reduced ration, or 21 d of reduced ration. Treatments that are statistically different (P<0.05) have different letters.Discussion The responses of gizzard and threadfin shad to cold shock alone and to a combination of starvation and cold shock were measured to gain insight into various factors that may contribute to impingement of these species at CWIS. Swimming endurance, cortisol, and chloride levels of gizzard shad and threadfin shad all responded to cold shock treatment, though not always as expected.-

4-14 Assessing Cold Shock Effects through Performance and Physiological Response Swimming endurance of gizzard shad acclimated to 15'C was reduced at water temperatures of 4 to 5°C, suggesting that susceptibility to impingement likely increases at these temperatures and below. For threadfin shad, we did not find a statistically significant decrease in endurance at 8.5°C, but that appears to be the point below which we are likely to see effects. Significant effects were observed at a test exposure temperature of 7.5°C. Similarly, Griffith and Tomljanovich (1975) showed that the ability of threadfin shad to resist impingement was severely impaired at temperatures below 8°C, but at higher temperatures impingement was slightly or not at all impaired.

The temperature at which threadfin shad were affected was warmer than. for gizzard shad, making them more susceptible to cold-stress-related impingement when the two occur in the same water body. It is worth noting that most of the shad used in the control trials were able to sustain swimming for the maximum period of 60 min at a velocity of 0.5 ft/s, which is the velocity often used as design criteria for cooling water intake screens.Cortisol was expected to increase as a response to cold-shock-induced stress, which has been observed in similar studies. Hyvarinen et al. (2004) found increasing cortisol levelswhen brown trout were cold shocked in an ice bath. In this study, we found the expected response for gizzard shad, but for threadfin shad, we found the opposite response.

This may be due to a reduced ability of threadfin shad to mount a stress response under abnormally cold temperatures, as was reported by Strange (1980) for channel catfish. Davis (2004) also showed that fish held at colder temperatures had delayed responses in cortisol (and chloride) in comparison to those fish held at warmer temperatures.

Alternatively, the lack of a statistically significant response by threadfin shad could be the result of the control group experiencing unknown stressors such as reduced water quality or handling effects that also elevated cortisol levels. The cortisol levels in the control groups for both species were higher than resting values reported for most fish species (0-50 ng/mL; Davis 2004); however, no published research involving shad cortisol levels was found for comparison.

Because the control group had abnormally higher levels of cortisol compared to reported resting levels for other species, we suspect that the presence of an unknown stressor is the most likely explanation for the threadfin shad outcome.Chloride levels in fish typically decline in response to a stressor.

For example, Miles et al.(1974) observed decreases in plasma chloride in muskellunge (Esox masquinongy) resulting from capture and handling.

However, we found in this experiment that levels usually increased with cold shock. Baseline chloride values were lower in all groups than those typically reported for unstressed fish (100-130 mEq/L; Barton et al. 2002). As with cortisol, there may have been an unaccounted for stressor that affected the fish while held in the laboratory.

Additionally, the acclimation period of one week at 15oC may not have been sufficient to stabilize osmoregulatory function in this species, or perhaps laboratory confinement was more stressful for these species than those species tested by other investigators.

One objective of this study was to find indicators of susceptibility to impingement.

We compared the bioindicator responses to swimming endurance and found cortisol and chloride in gizzard shad to be negatively correlated with endurance, which suggests that either of these could be potential indicators of susceptibility to impingement.

In most species, chloride changes are the inverse of cortisol (Davis 2004), but in this case chloride response tracked that of cortisol.Johansen et al. (1994) found that when cortisol levels of rainbow trout increased above resting levels due to a stressor (toxicant), swimming performance decreased.

4-15 Assessing Cold Shock Effects through PerJbrmance and Physiological Response Prolonged exposure at cold temperatures seemed to worsen the effect on swimming endurance for both species,.

With extended exposure of 3-6 hr at a test temperature, we found no evidence of additional stress in cortisol and chloride measures.

To the contrary, based on cortisol in gizzard shad and both cortisol and chloride in threadfin shad, there appeared to be acclimation or recovery from stress. Strange (1980) showed that channel catfish became acclimated to stress after several days and cortisol subsequently declined.

Similarly, Strange and Schreck (1978)showed that cortisol levels in juvenile Chinook salmon (Oncorhynchus tshawytscha) began to decrease 3.5 hr after a stressor was presented and removed.Compromised nutritional status as a result of several weeks or months of reduced food availability has been correlated with impingement of fish in late winter and early spring (Adams et al. 1985). Previous studies on a variety of fish species indicated that swimming performance, total protein, triglycerides, hematocrit, and condition factor would decline as the duration of the starvation increased.

Martinez et'al. (2004) demonstrated that starved Atlantic cod (Gadus morhua) had reduced swimming performance compared to cod that were fed. McMillan and Houlihan (1991) reported rainbow trout having reduced serum total protein after several days of fasting. Ruane et al. (2002) compared triglyceride levels in common carp (Cyprinus carpio) fed different rations and found a direct relationship between triglyceride and ration. Adams et al.(1985) reported lower hematocrit and condition factor levels in stressed gizzard shad compared to unstressed shad. In our study, gizzard and threadfin shad showed little response in swimming endurance or in the short-term stress indicators (cortisol and chloride) after 14 and 21 d of reduced ration followed by cold shock. The treatments did result in lowered condition factor and lowered blood hematocrit levels. We did not find a relationship between swimming endurance and any of the physiological indicators that was common between the two species. Either the lack of feeding had no effect on the stress response or the period of starvation was not long enough to cause an observed affect. Since these species typically experience periods of low food availability in winter, possible adaptation to periods of reduced feeding could occur, therefore helping to explain, in part, the lack of a clearresponse in the lab to reduced ration.To better understand the implications of reduced ration under natural conditions, we collected gizzard and threadfin shad from the Clinch River in March 2006 after a winter period when feeding was greatly reduced. These fish had significantly lower condition factors, (7.4 for gizzard and 6.7 for threadfin shad) than those we had collected during the summer and held for 21 d under reduced ration (8.1 for gizzard and 6.9 for threadfin shad). Therefore, even though the reduced ration period of 21 d in the laboratory resulted in poorer condition compared to controls, condition of fish in the lab did not quite approximate that of shad collected from the reservoir in late winter. If the condition of fish in the lab had been similar to that of shad collected in the field in late winter, greater declines in nutritional status indicators and swimming performance may have occurred in those fish subjected to cold shock treatment.

Changes in hematocrit and condition factor were significant in threadfin shad but not gizzard shad after 21 d of reduced ration. This differential response between species is possibly due to gizzard shad storing proportionately greater amounts of lipids than threadfin shad (Adams 1999).Hematocrit and condition factor are relatively simple indicators that could be used in the field to rapidly determine susceptibility to impingement.

These are the types of rapid assessment indicators that might be used to detect impairment of fish prior to impingement.

The applicability of these measures and other easily and rapidly applied indicators of susceptibility could be 4-16 Assessing Cold Shock Effects through Performance and Physiological Response further assessed by investigating physiology and swimming performance of shad whose condition replicates the condition of shad collected from the water body in late winter. Such laboratory studies could define the relationships between environmental stresses (cold shock or starvation) and responses of individual.

fish (e.g., hematocrit and condition) and subsequent changes in swimming performance and susceptibility to impingement.

Once the relationships are established, field studies could be designed to predict the potential for large impingement events based on measurements of environmental or physiological state.The overall results of this study indicate that rapid declines in temperature and cold temperatures, particularly those slightly above the temperatures of LOE, would render gizzard and threadfin shad more susceptibl to impingement.

Potential indicators of susceptibility to impingement have been identified in this study (e.g., hematocrit and condition factor) and could be performed on fish in the vicinity of intake structures as a preliminary assessment of the applicability of this assessment technique.

The use of multiple indicators of stress helps detect and account for confounding stressors which may be present in natural ecosystems.

Using physiological and performance-level indicators to assess impingement susceptibility appears promising, but further studies are necessary to evaluate the relative importance of varying cold shock regimes and nutritional status to impingement susceptibility.

More testing is needed for both species on the effects of:* rate of temperature decline relative to the acclimation temperature," lower acclimation temperatures relative to the cold shock test temperatures, and* a longer acclimation period prior to testing.Further research addressing the role and importance of nutritional status on impingement susceptibility should include:* longer starvation periods using fish collected in late winter," combining several different cold shock temperatures with the reduced ration treatment, and" analysis of the physiological recovery of fish held under reduced ration and cold shocked.This type of information would clarify the relationship between physiological indicators and susceptibility to impingement and increase capability for predicting and assessing impingement mortality.

4-17 5

SUMMARY

Summary of Results The literature on mass mortalities of clupeid species reveals that such events are common, especially in larger freshwater lakes, rivers and reservoirs, and brackish and marine embayments.

The principal reasons for such die-offs often vary among species. Research into the causes of this mortality as well as the general physiological responses, of clupeids to potential environmental stressors is limited.More reports on gizzard shad die-offs were found than for the other clupeid species, though this does not necessarily mean this species is affected more often or is more susceptible.

Accompanying studies often provided detailed information on the physiological response of gizzard shad to thermal stress and provided clues to link mass mortalities to cold stress.Researchers found that the amount of stored lipids appears to play a role in determining winter kill of several clupeid species, but that parameter in itself is not an effective means of determining cold stress mortality in gizzard shad. Alewife die-offs seemed to be linked to severe winters, but there also appears to be a density-related factor. For example, greater mortality has been observed in a less-severe winter when population density was high than in a severe winter with lower alewife densities.

Threadfin shad are native to the southern United States, but have been introduced as a forage base to many higher latitude states where they commonly suffer winter mortality.

The inability to survive the winter in some locales has been used as a benefit by fisheries biologists trying to better control managed fish populations.

Although mortalities are often severe following adverse conditions, this species has the ability to quickly repopulate a water body (McLean et al. 1980). Mass menhaden mortality appears most likely a result of a sudden change in water quality or disease.An underlying hypothesis of the laboratory experiments presented in this report is that fish that become impinged represent a portion of the population that is in some way compromised or weaker than individuals that are not impinged.

Our studies were not designed to identify the survivors or the fit individuals, but to better understand the lack of fitness of those that are most susceptible to impingement.

In studies on lower critical thermal limits, we found that threadfin shad acclimated at 15'C began to exhibit loss of equilibrium at 6.0°C, with a CTMin (median LOE) of 4.8°C. The first. gizzard, shad to lose equilibrium occurred at a lower temperature, 2.7°C, with a CTMin of 1.8°C. Shad acclimated to temperatures

<15'C would probably have slightly lower CTMins, and exposure to a different rate of temperature, change would also have an effect on the CTMin. To investigate the response to the most extreme rate of temperature change, we plunged gizzard shad 5-1 Summary acclimated at 15'C directly into water at either 4 or 6°C. No fish lost equilibrium at 6°C and all fish eventually lost equilibrium when plunged into 4VC water.An interesting finding in our study related to the ability of gizzard shad to recover from cold shock. For fish that lost equilibrium during a gradual drop in temperature, apparent recovery occurred within 15 min of being placed into water that was no more~than 2°C higher than the temperature at which they experienced LOE. It is worth noting that the length of time that fish were in a state of disequilibrium prior to being exposed to warmer temperatures during the experiment was short (on the order of a few minutes).

A longer exposure to debilitating temperatures before warming is more likely in the field, which would likely reduce the rate of recovery.

For those that lost equilibrium during the plunge experiments, 80 % eventually recovered when the water temperature was slowly raised over the next several days. For those fish that did not recover, mortality did not happen immediately, but occurred 3-4 d after the initial plunge.The results of the CTMin and recovery experiments suggest that determining when a gizzard or threadfin shad becomes moribund is not straightforward, because under some circumstances fish that appear debilitated might just be temporarily impaired and might recover. These distinctions are important when trying to evaluate the relative contributions of natural causes and CWIS to fish impingement and mortality.

We also reported here on studies of the responses of gizzard and threadfin shad to cold shock alone and to a combination of starvation and cold shock to gain insight into factors that.contribute to impingement of these species at CWIS. We expected that shad acclimated at 15'C would experience effects on swimming endurance as temperature fell below 8°C (for threadfin shad) and below 5°C (for gizzard shad). These values are about 3°C above the CTMin values for these species that we determined in separate experiments, and about 1-2°C above the point at which we observed apparent recovery from LOE in static water tanks. In an effort to simulate late winter nutritional status we also subjected some fish to 2-3 weeks of near starvation, but found that this did not produce an additional negative effect on swimming endurance.

Subsequent field sampling.suggests that a longer period of starvation is needed to simulate late-winter field conditions.

We evaluated two biochemical stress indicators for a response to cold shock alone and found that both blood serum cortisol and chloride responded to cold shock, but the responses were not consistent enough to conclude that these indicators would be useful for evaluating cold shock or predicting impingement susceptibility.

The results are not easily interpreted because of the interacting effects of stress accumulation, acclimation, and recovery as well as a potential inability to mount a stress response as the organism's physiological systems become compromised due to continual stress exposure.We examined the interaction between nutritional status and stress response by evaluating additional bioindicators

-hematocrit, total protein, and triglycerides.

For both shad species, hematocrit responded negatively with increased starvation, and triglycerides increased after 14 d starvation and then decreased after 7 more days. There was no relationship for either parameter with swimming endurance.

5-2 Summary The overall results of this study confirm that cold temperatures and cold shock as a result of a rapid decline in temperature can render gizzard and threadfin shad more susceptible to.impingement.

Potential indicators of susceptibility to impingement have been identified in this study (e.g., hematocrit and condition factor) and could be analyzed for fish in the vicinity of intake structures as a preliminary assessment of the applicability of this assessment technique.

The use of multiple indicators of stress may help to explain confounding stressors that may be present in natural ecosystems.

The results of this study can also be useful for identifying the environmental conditions under which one might expect that the cause of impingement is largely of natural origin. For example, when thermal regimes at a CWIS are similar to those that resulted in loss of equilibrium in laboratory experiments, we would expect that the bulk of impinged fish were not directly killed by impingement.

By comparing historic temperatures at a site to those tested in the laboratory it might be possible to designate entire seasons when impingement is likely a result of primarily natural causes. Both of these approaches were recently proposed by Muscatine Power and approved by EPA Region VII as a means to assign likely cause of death during winter impingement events (USEPA 2006)Future research needs Field evaluations of the condition of fish (e.g., living, dead, moribund, recoverable) prior to impingement can be difficult, but power industry, regulatory agency, and resource agency personnel need to estimate the proportions of impinged fish that are already dead or dying when they become impinged.

Laboratory studies of fish response to cold stress can help explain episodic impingement observations at operating power plants.Using physiological and performance-level indicators to assess impingement susceptibility appears promising, but further studies are.needed to evaluate the relative importance of cold shock and nutritional status on impingement.

Future studies should be designed to address the following questions: " Is there a difference between that fraction of a population, including a particular size and/or age groups, that gets impinged and the rest of the population?

• Are there bioindicators that can be used to predict when impingement is eminent or likely?Can they be readily measured at a reasonable cost?* Similarly, can lab-based empirical results be used to predict which environmental conditions are likely to result in an impingement event?* Are there indicators that can be used to evaluate the contribution of natural causes to impingement on intake screens?Future testing on cold shock should include analyses of: " rates of temperature decline,* acclimation temperatures,* acclimation durations, and 5-3 Summary 0 various combinations of the above.Further research addressing the role and importance of nutritional status on impingement susceptibility should include:* laboratory experiments with longer starvation periods using fish collected in late winter,* combining different cold shock temperatures with the reduced ration treatment, and* analysis of nutritional bioindicators in fish collected from the field during different seasons.and at different nutritional levels.There are other indicators than those used in our study that might be good predictors of susceptibility to impingement.

Future work on other bioindicators should focus on the following classes of indicators:

• Performance:

This class includes tests that relate to a fish's ability to escape or avoid impingement and could include experiments that test swimming endurance (as presented in this report) and high speed video analysis of startle response.* Physiological condition:

In this report we used cortisol and chloride as indicators of exposure to a stressor.

There are other indicators that could be used as indicators of organ dysfunction, osmoregulation, and carbohydrate and protein metabolism.

In addition, there. are new genomic and proteomic techniques that evaluate the suite of proteins manufactured by an organism in response to stress and how that suite changes in response to different stressors.

• Nutritional/bioenergetic:

There are several indicators of nutritional status or general condition that might have a predictable relationship to impingement susceptibility or swimming performance (e.g., condition factor, liver-somatic index, visceral-somnatic index, spleno-somatic index, serum triglycerides and cholesterol, and body lipids and phospholipids).

Such studies could clarify the relationships between physiological indicators and susceptibility to impingement, and thereby increase our ability to predict and assess impingement mortality.

Laboratory data would help in the design of adequate field tests of these techniques, providing preliminary information on the numbers of fish to sample and the sampling frequency needed to determine background states and rates of change. Compared to our controlled experiments, field studies of the causes of increased susceptibility to impingement would need to account for complicating factors that might confound predictions from the laboratory-based responses.

For example, water temperature changes in nature are rarely as uniform as those tested in these experiments, but rather exhibit decreases and increases in an irregular pattern. The presence of.thermal refugia in the river or reservoir may protect fish from debilitating temperature decreases, resulting in fewer moribund or impaired fish than would be predicted from these studies. Thus, while it is recognized that measuring many of these physiological indicators as early warning signs of imminent episodic impingement events may not be practical at most power plants, the findings would provide possible explanations for the occurrences of such events.Lastly, an alternative approach to finding bioindicators of susceptibility to impingement prior to impingement is one that identifies post-mortem indicators of health status prior to impingement (e.g., death or moribund).

Candidate indicators could be those that indicate the cause of death or 5-4 Summary those that indicate time of death. For example, quantifying how gill color and eye opacity change after death under different environmental conditions could be used to establish a time of death relative to time of impingement.

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Final report, October 1, 1978 -September 30, 1980. ORNL/NUREG/TM-339, Oak Ridge National Laboratory, Oak Ridge, TN. 69 p.McLean, R. B., J. S. Griffith, and M. V. McGee. 1985. Threadfin shad, Dorosoma petenense Guinther, mortality:

causes and ecological implications in a South-eastern United States reservoir.

Journal of Fish Biology. 27:1-12.McMillan, D.N., and D. F. Houlihan.

1991. Protein synthesis in trout liver is stimulated by both-feeding and fasting. Fish Physiology and Biochemistry 10(1): 23-34.Michaletz, P. H. 1997. Factors affecting abundance, growth, and survival of age-0 gizzard shad.Transactions of the American Fisheries Society. 126:84-100.

Michaletz, P. H. 1998. Population characteristics of gizzard shad in Missouri reservoirs and their)relation o reservoir productivity, mean depth, and sport fish growth. North American Journal of Fisheries Management.

18:114-123.,Miles, H. M., S. M. Loehner, D. T. Michaud, and S. L. Salivar. 1974. Physiological responses of hatchery reared muskellunge (Esox masquinongy) to handling.

Transactions of the American Fisheries Society 103(2):336-342.

Moyle, P. B. 2002. Inland Fishes of California.

Regents of the University of California.

pp. 114-116.North Carolina Division of Water Quality (NCDWQ). 2002. Annual Report of Fish Kill Events.Water Quality Section. Raleigh, NC.Neumann, D. A., W. J. Wachter, E. L. Melinsky and D. G. Bardarik.

1977. Field and laboratory assessment of factors affecting the occurrence and distribution of gizzard shad (Dorosoma cepedianum) at Front Street Steam Electric Generation Station, Erie, Pennsylvania.

Pennsylvania Electric Company.Noga, E. J., J. F. Wright, J. F. Levine, M. J. Dykstra, and J. H. Hawkins. 1991. Dermatological diseases affecting fishes of the Tar-Pamlico estuary, North Carolina.

Dis. Aquat. Org. 10: 87-92.(As cited in Smith 1999).O'Gorman, R. and C. P. Schneider.

1986. Dynamics of alewives in Lake Ontario following mass mortality.

Transactions of the American Fisheries Society. 115(1): 1-14.Oklahoma Department of Wildlife Conservation.

2001. http://www.wildlifedepartment.com/08-0 lnr.htm 6-6 Literature Cited Oviatt, C. A., A. L. Gall, and S. W. Nixon. 1972. Environmental effects of Atlantic menhaden on surrounding waters. Chesapeake Science 13(4):321-323.

Pflieger, W. L. 1997. The Fishes of Missouri.

Missouri Department of Conservation.

Jefferson City, Missouri.Pritchard, A.L. 1929. The alewife in Lake Ontario. University of Toronto Studies Biological Series Publication 33, Publication of the Ontario Fisheries Research Laboratory 38:37-54, Toronto. (As cited in Flath and Diana 1985).Ross, Q. E., D. J. Dunning, J. K. Menezes, M. J. Kenna, Jr., and G. Tiller. 1996. Reducing impingement of alewives with high-frequency sound at a power plant intake on Lake Ontario.North American Journal of Fisheries Management.

16:548-559.

Ruane, N. M., E. A. Huisman, and J. Komen. 2002. The influence of feeding history on the acute stress response of common carp. Aquaculture 210(1-4):

245-257.Schael, D. M., J. A. Rice, and D. J. Degan. 1i995. Spatial and temporal distribution of threadfin shad in a Southeastern reservoir.

Transactions of the American Fisheries Society. 124: 804-812.Schneider, C. P. and T. Schaner. 1994. The status of pelagic prey stocks in Lake Ontario in 1993.New York State Department of Environmental Conservation 1994 Annual Report from Bureau of Fisheries Lake Ontario Unit to the Lake Ontario Committee and the Great Lakes Fishery Commission, Ann Arbor, Michigan.

Cited in Ross and Dunning 1996.Shuter, B. J. and J. R. Post. 1990. Climate, populations viability, and the zoogeography of temperate fishes. Transactions of the American Fisheries Society. 119:314-336.

Cited in Michaletz 1998.Sindermann, C. J. 1988. Epizootic ulcerative syndromes in coastal/estuarine fish. U.S. Dept.Commer., NOAA Tech. Memo. NMFS-F/NEC-54, 37p. (As cited in Smith 1999).Smith, J. W. 1999. A large fish kill of Atlantic menhaden, Brevoortia tyrannus, on the North Carolina coast. The Journal of the Elisha MitchellScientific Society. 115(3): 157-163.Smith, S.E. 1968. Species succession and fishery exploitation in the Great Lakes. Journal of the Fisheries Research Board of Canada 25:667-693.

Stanley, J. G. and P. J. Colby. 1971. Effects of temperature on electrolyte balance and osmoregulation in the alewife (Alosa pseudoharengus) in fresh and sea water. Transactions of the American Fisheries Society. 4:624-638.

Stephens, E. B., M. W. Newman, A. L. Zachary, and F. M. Hetrick. 1980. A viral aetiology for the annual spring epizootics of Atlantic menhaden Brevoortia tyrannus in Chesapeake Bay. J.Fish. Dis. 3:387-398. (As cited in Smith 1999)..6-7 Literature Cited Stock, J. N. 1971. A study of some effects of population density on gizzard shad and bluegill growth and recruitment in ponds. Master's thesis. University of Missouri, Columbia.

Cited in Michaletz 1998.Strange, R. J., and C. B. Schreck. 1978. Cortisol concentrations in confined juvenile Chinook salmon (Oncorhynchus tshawytscha

). Transactions of the American FisheriesSociety 107(6):812-819.

Strange, R. J. 1980. Acclimation temperature influences cortisol and glucose concentrations in stressed channel catfish. Transactions of the American Fisheries Society 109: 298-303.Strawn, K. 1965. Resistance of threadfin shad to low temperatures.

Proceedings of the Annual Conference of the Southeastern Association Game and Fish Commission.

17:290-293.

Trautman, M. B. 1928. Ducks feeding on gizzard shad. Ohio State Mus. Sci. Bull. No. 1, p.2 8.(As cited in White et al. 1986).Trautman, M. B. 1940. The birds of Buckeye Lake, Ohio. Misc. Publ. Mus. Zool. Univ. Mich.No. 44. pp. 110-111. (As cited in White et al. 1986).Texas Utilities Electric Company (TUEC). 1994. Comanche Peak Steam Electric Station, Texas 316(b) Demonstration 1993-1994.

U.S. Environmental Protection Agency (USEPA). 2006. Letter from John A. Dunn, USEPA Region VII to Steve Williams, Iowa Department of Natural Resources.

November 27, 2006.Virginia Department of Game and Inland Fisheries.

2004. Smith Mountain Lake Fisheries Management Report.http://www.dgif.state.va.us/fishing/lakes/smith-mountain-lake/documents/SMLRptO4.pdf.

Van Belle, G. 2002. Statistical rules of thumb. Page 10 in Wiley series in probability and statistics.

John Wiley & Sons, NY, NY.Vaughan, D. S. 1990. Assessment of the status of the Atlantic menhaden stock with reference to internal waters processing.

U.S. Dept. Commer., NOAA Tech. Rept., NMFS-SEFC-262, 20 p.Walburg, C. H. 1964. Fish population studies, Lewis and Clark Lake, Missouri River, 1956 to 1962. U.S. Fish and Wildlife Service, Special Scientific Report.- Fisheries No. 482, Washington, D.C.Warshaw, S. J. 1972. Effects of alewives on zooplankton of Lake Wononskopomuc, Connecticut.

Limnology and Oceanography 17:816-825.

Welker, M. T., C. L. Pierce, and D. H. Wahl. 1994. Growth and survival of larval fishes: roles of competition and zooplankton abundance.

Transactions of the American Fisheries Society 123:703-717.

6-8 Literature Cited Westman, J. R. and R. F. Nigreli. 1955. Preliminary studies of menhaden and their mass mortalities in Long Island and New Jersey Waters. N.Y. Fish Game J. 2:142-153. (As cited in Smith 1999).White, A. M., F. D. Moore, N. A. Alldridge, and D. M. Loucks. 1986. The effects of natural winter stresses on the mortality of the eastern gizzard shad, Dorosoma cepedianum, in Lake Erie.Environmental Resource Associates, Inc. Report 78. Cleveland, Ohio.Wolters, W. R., and C. C. Coutant. 1976. The effects of cold shock on the vulnerability of young bluegill to predation.

Thermal Ecology II, ERDA Symposium, Savannah River Ecology Laboratory, Georgia, p. 162-164.6-9 A APPENDIX Cumulative stress-induced mortality of gizzard shad in a southeastern U.S. reservoir.

Adams, S. M., J. E. Breck, and R. B. McLean. 1985. Environmental Biology of Fishes.13:103-112.

Report summarizes the 1983 spring die-off of gizzard shad in Watts Bar Reservoir, TN. A combination of environmental factors led to the depletion of lipid reserves causing large mortality in gizzard shad population.

Observations of ulcerative mycosis infections of Atlantic menhaden (Brevoortia tyrannus).

Ahrenholz, D. W., J. F. Guthrie, and R. M. Clayton. 1987. U.S. Dept. Commer., NOAA Tech. Memo. NMFS-SEFC-196, 28p.Fishery management plan for Atlantic menhaden, 1992 revision.

Atlantic Menhaden Advisory Committee (AMAC). 1992. Atl. States Mar. Fish. Comm., Fish Mgt. Rept. No. 22, 1 5 9 p.Distribution of alewives in southeastern Lake Ontario in autumn and winter: a clue to winter mortalities.

Bergstedt, R.A. and R. O'Gorman.

1989. Transactions of the American Fisheries Society 118:687-692.

Details the distribution of alewife and water temperatures profiles in southeastern Lake Erie in autumn and winter 1981-1984.

Relates water temperatures at different depths and the relation between minimum winter water temperatures and mass alewife die-off. Also provides information on the ability of alewife to descend below normal depth ranges to escape lower temperatures during severe winters.Population characteristics and physical condition of alewives in a massive die-off in Lake Michigan, 1967. Brown, E.H., Jr. 1968. Great Lakes Fishery Commission, Ann Arbor, MI, USA. Dead and dying alewife were compared with those collected in trawl survey to assess condition of body and gonads, stomach contents, and the incidence of disease and external anomalies.

Population biology of alewives in Lake Michigan, 1948-70. Brown, E.H., Jr. 1972. Journal of Fisheries Research Board of Canada 29:477-500.

Burkholder, J. M., E. J. Noga, C. H. Hobbs, and H. B. Glasgow, Jr. 1992. New "phantom" dinoflagellate is causative agent of major estuarine fish kills. Nature. 358:407-410.

Cold shock: effect of rate of thermal decrease on Atlantic menhaden.

Burton, D. T., P. R.Abell; and T. P. Capizzi. 1979. Marine Pollution Bulletin.

10:347-349.

Study assesses the effects of various rates of thermal decrease on mortality of juvenile Atlantic menhaden.

The study is designed to simulate various rates of winter shutdown at large power plants to examine mortality rates of menhaden at different rates of temperature decline.A-1 Appendix Differential growth of young-of-year gizzard shad in several Kentucky reservoirs.

Buynak, G.L., R.S. Hale, and B. Mitchell.

1992. North American Journal of Fisheries Management 12:656-662.

Study relating size of YOY gizzard shad to population density and time of spawning in two Kentucky reservoirs.

The size of YOY gizzard shad was density dependent, with growth inversely proportional to density.Caroots, M. S. 1976. A study of the Eastern gizzard shad, Dorosoma cepedianum, from Lake Erie. MS Thesis, John Carroll University, University Heights, Ohio.Colby, P.J. 1973. Response of the alewives to environmental change. U.S. Fish and Wildlife Service, Great Lakes Fishery Laboratory Contribution 472, Ann Arbor, MI, USA.Conniff, R. 1992. They come, they die, they stink to high heaven. Yankee Mag. June 1992:82-116.

Cooper, E. L. 1983. Fishes of Pennsylvania and the Northeastern United States. The Pennsylvania State University Press, University park, PA. pp. 243.Cold shock to aquatic organisms:

guidance for power-plant siting, design, and operation.

Coutant, C. C. 1977. Nuclear Safety. 18(3):329-342.

Documents cold shock mortalities at various power plants as a results of winter shutdown.

Details methods to reduce sudden cold shock to aquatic organisms.

Cox, D. K. and C. C. Coutant. 1975. Acute cold-shock resistance of gizzard shad. Thermal Ecology II, ERDA Symposium, Augusta, Georgia, p.159.Complex interactions between fish and zooplankton:

quantifying the role of an open-water planktivore.

DeVries, D. R. and R. A. Stein. 1992. Canadian Journal of Fisheries and Aquatics Sciences.

49:1216-1227.

Details interactions between gizzard shad, zooplankton and other fish species in an Ohio reservoir.

Zooplankton density declined drastically shortly after the introduction of gizzard shad, which also reduced recruitment of bluegills.

Recent changes in Lake Michigan's fish community and their probable causes, with emphasis on the role of alewife. Eck, G.W. and L. Wells. 1987. Canadian Journal of Fisheries and Aquatic Sciences 44(Supplement 2): 53-60. Outlines the major changes in fish population of Lake Michigan including the decline of alewife and the increase in native species and large salmonids.

The report also provides possible causes of the changes in the fish community in the early to mid 1980's.Faisal, M. and W. J. Hargis, Jr. 1992. Augmentation of mitogen-induced lymphocyte proliferation in Atlantic menhaden, Brevoortia tyrannus, with ulcer disease syndrome.

Fish Shellfish Immunol. 2:33-42.Seasonal energy dynamics of the alewife in Southeastern Lake Michigan.

Flath, L. E,. and J.S. Diana. 1985. Transactions of the American Fisheries Society. 114:328-337.

Alewife from Lake Michigan were analyzed for caloric content, lipid, and lean dry weight to determine A-2 Appendix seasonal energy dynamics in an effort to relate alewife condition to winter die-off. Annual die-offs correlated with seasonal energy lows.Graham, J.J. 1956. Observations on the alewife in freshwater.

Ontario Fisheries Research Laboratory Publication 74, Toronto, Canada.Susceptibility of threadfin shad to impingement.

Griffith, J. S. and D. A. Tomljanovich.

1975. Proceedings of the 29th Annual Conference of the Southeastern Association of Game and Fish Commissioners.

223-234. Threadfin shad impingement at 13 Tennessee Valley Authority power plants was analyzed to determine mortality resulting from cold stress. In addition laboratory experiments Were conducted to evaluate the ability of cold-stressed threadfin shad to avoid impingement.

Threadfin shad were stressed at 12'C and impingement mortality increased at temperatures below 8°C.Effects of low temperature on the survival and behavior of threadfin shad, Dorosoma petenense.

Griffith, J. S. 1978. Transactions of the American Fisheries Society. 107(1): 63-70. Study details survival of threadfin shad at gradual and rapid decreases in temperature.

At temperatures .of 6 to 7°C threadfin shad exhibited a decreased responsiveness and reduced swimming ability and at a temperature of 5°C, all threadfin shad died.Heidinger, R. C. 1983. Life history of the gizzard shad and threadfin shad as it relates to the ecology of small lakes fisheries.

Proc. Of Small Lakes Management Workshop -Pros and Cons of Shad. Iowa Conservation Commission and Sport Fishery Institute, Des Moines.Forage species production techniques.

Higginbotham, B. 1988. Southern Regional Aquaculture Center Publication No. 141. Details life history of threadfin shad in southeastern ponds and reservoirs.

Jester, D. B. and B. L. Jensen. 1972. Life history and ecology of the gizzard shad, Dorosoma cepedianum, with reference to Elephant Butte Lake. Agr. Exp. Res. Rpt. 218.Johnson, B. M., R. A. Stein, and R. F. Carline. 1988. Use of quadrat rotenone technique and bioenergetics modeling to evaluate prey availability to stocked piscivores.

Transactions of the American Fisheries Society. 117: 127-141.Kampa, J.M. 1984. Density-dependent regulation of gizzard shad populations in experimental ponds. Master's thesis. University of Missouri, Columbia.Consequences of an alewife die-off to fish and zooplankton in a reservoir.

Kohler, C. C. and J. J. Ney. 1981. Transactions of the American Fisheries Society. 110:360-369.

Outlines changes in alewife population and zooplankton community in Claytor Lake, VA. Details changes in size structure of zooplankton community following alewife die-off and impacts to other resident fish species.A-3 Appendix An analysis of factors influencing the impingement of threadfin shad at power plants in the Southeastern United States. Loar, J. M., J. S. Griffith, and K. D. Kumar. 1978. Fourth National Workshop on Entrainment and Impingement.

245-255. Study to identify factors affecting impingement of threadfin shad at southeastern power plants. Important factois included water temperature and distribution and abundance of threadfin shad in the cooling water source.Thermal tolerance of the alewife. McCauley, R. W. and F. P. Binkowski.

1982.Transactions of the American Fisheries Society. 111:389-391.

Study evaluates upper lethal temperatures of adult alewife in an effort to evaluate spring mortality caused by thermal stress of adult alewife encountering warm inshore waters.Threadfin shad impingement:

effect of cold stress. McLean, R. B., P. T. Singley, J. S.Griffith, and M. V. McGee. 1980. Report to the Nuclear Regulatory Commission.

Publication No. 1495. Evaluates natural winter mortality of threadfin and YOY gizzard shad and relates mortalities to power plant impingement.

Blood serum electrolytes, were not predictors of cold stress for YOY gizzard shad. Research tries to determine physical and biological causes of threadfin shad impingement at Kingston Power Plant, TN and to evaluate the impact of impingement on threadfin shad population structure, as well as predator populations.

Threadfin shad impingement:

population response.

McLean, R. B., P. T. Singley, and D.Lodge. 1981. Final report to the Nuclear Regulatory Commission.

Publication No. 1713.Study used trawling and a sonar system to assess larval, juvenile, and adult stock abundance in an effort to evaluate recovery of threadfin shad population following winter kill.Threadfin shad, Dorosoma petenense Guinther, mortality:

causes and ecological implications in a South-eastern United States reservoir.

McLean, R. B., J. S. Griffith, and M. V. McGee. 1985. Journal of Fish Biology. 27:1-12, Cold stress identified as an important factor influencing threadfin shad mortality andimpingement in Watts Bar Reservoir, TN. Cold stress left threadfin shad vulnerable to predation, as 99 % of the diet of sauger and skipjack herring consisted of threadfin shad from November until January when threadfin shad disappeared.

Factors affecting abundance, growth, and survival of age-O gizzard shad. Michaletz, P. H.1997. Transactions of the American Fisheries Society. 126:84-100.

Growth of YOY gizzard shad was positively correlated by temperature and to a lesser degree food availability.

Early cohorts suffered higher mortalities than late cohorts.Population characteristics of gizzard shad in Missouri reservoirs and their relation to reservoir productivity, mean depth, and sport fish growth. Michaletz, P. H. 1998. North American Journal of Fisheries Management.

18:114-123.

Report analyzed gizzard shad growth in 14 Missouri reservoirs to relate lake productivity and mean depth to overall growth.Gizzard shad grew faster in lakes with higher production, but sport fish grew faster in deeper, less productive lakes in which gizzard shad grew slower.Moyle, P. B. 2002. Inland Fishes of California.

Regents of the University of California.

pp.114-116.A-4 Appendix Neumann, D. A., W. J. Wachter, E. L. Melisky, and D. G. Bardarik.

1977. Field and laboratory assessment of factors affecting the occurrence and distribution of gizzard shad (Dorosoma cepedianum) at Front Street Steam Electric Generating Station, Erie, Pennsylvania.

Pennsylvania Electric Company.Noga, E. J., J. F. Wright, J. F. Levine, M. J. Dykstra, and J. H. Hawkins. 1991.Dermatological diseases affecting fishes of the Tar-Pamlico estuary, North Carolina.

Dis.Aquat. Org. 10:87-92.Dynamics of alewives in Lake Ontario following mass mortality.

O'Gorman, R. and C. P.Schneider.

1986. Transactions of the American Fisheries Society. 115(1): 1-14. Alewife in Lake Ontario quickly recovered following the massive die-off in the winter of 1976-1977.

Ability of the alewife population to quickly recover has been attributed to the longevity of survivors, high survival of yearlings, and the production of large year classes.Oviatt, C. A., A. L. Gall, and S. W. Nixon. 1972. Environmental effects of Atlantic menhaden on surrounding waters. Chesapeake Sci. 13:321-323.

Pflieger, W. L. 1997. The Fishes of Missouri.

Missouri Department of Conservation.

Jefferson City, Missouri.Pritchard, A.L. 1929. The alewife in Lake Ontario. University of Toronto Studies Biological Series Publication 33, Publication of the Ontario Fisheries Research Laboratory 38:37-54, Toronto.Reducing impingement of alewives with high-frequency sound at a power plant intake on Lake Ontario. Ross, Q. E., D. J. Dunning, J. K. Menezes, M. J. Kenna, Jr., and G. Tiller.1996. North American Journal of Fisheries Management.

16:548-559.

The study assessed the use of high-frequency sound to deter alewife at James A. FitzPatrick Nuclear Power Plant on Lake Ontario. The sound system reduced alewife impingement by 81-84 %.Spatial and temporal distribution of threadfin shad in a Southeastern reservoir.

Schael, D.M., J. A. Rice, and D. J. Degan. 1995. Transactions of the American Fisheries Society. 124: 804-812. Study used hydroacoustics to assess distribution, density, and depth of threadfin shad in Lake Norman, NC.Schneider, C.P. and T. Schaner. 1994. The status of pelagic prey stocks in Lake Ontario in 1993. New York State Department of Environmental Conservation 1994 Annual Report from Bureau of Fisheries Lake Ontario Unit to the Lake Ontario Committee and the Great Lakes Fishery Commission, Ann Arbor, Michigan.Shuter, B. J. and J. R. Post. 1990. Climate, populations viability, and the zoogeography of temperate fishes. Transactions of the American Fisheries Society. 119:314-336.

Sindermann, C. J. 1988. Epizootic ulcerative syndromes in coastal/estuarine fish. U.S. Dept.Commer., NOAA Tech. Memo. NMFS-F/NEC-54, 37p.A-5 Appendix A large fish kill of Atlantic menhaden, Brevoortia tyrannus, on the North Carolina coast.Smith, J. W. 1999. The Journal of the Elisha Mitchell Scientific Society. 115(3): 157-163.Details 1997 Atlantic menhaden kill and possible causes of large menhaden kills in recent times.Report suggests large menhaden kills are often the result of predators chasing large schools into small embayments.

The large number of fish quickly depletes available dissolved oxygen which creates anoxic conditions that fish are unable to escape.Smith, S.E. 1968. Species succession and fishery exploitation in the Great Lakes. Journal of the Fisheries Research Board of Canada 25:667-693.

Effects of temperature on electrolyte balance and osmoregulation in the alewife (Alosa pseudoharengus) in fresh and sea water. Stanley, J. G. and P. J. Colby. 1971. Transactions of the American Fisheries Society. 4:624-638.

Study researched the effects of cold temperature on electrolyte balance and osmoregulation in alewife. Cold stress caused ionoregulatory failure in the alewife studies. Large winter die-offs in Great Lakes may be a result of a failure to osmoregulate.

Stephens, E. B., M. W. Newman, A. L. Zachary, and F. M. Hetrick. 1980. A viral aetiology for the annual spring epizootics of Atlantic menhaden Brevoortia tyrannus in Chesapeake Bay. J. Fish. Dis. 3:387-398.

Stock, J.N. 1971. A study of some effects of population density on gizzard shad and bluegill growth and recruitment in ponds. Master's thesis. University of Missouri, Columbia.Strawn, K. 1965. Resistance of threadfin shad to low temperatures.

Proc. Annu. Conf.Southeast.

Assoc. Game Fish Comm. 17:290-293.

Trautman, M. B. 1981. The Fishes of Ohio. Ohio State University Press. Columbus, Ohio, pp 210-204.Vaughan, D. S. 1990. Assessment of the status of the Atlantic menhaden stock with reference to internal waters processing.

U.S. Dep. Commer., NOAA Tech. Rept., NMFS-SEFC-262, 20p.Effects of alewives on zooplankton of Lake Wononskopomuc, Connecticut.

Warshaw, S.J.1972. Limnology and Oceanography 17:816-825.

Details effect of alewife predation on zooplankton community in Lake Wononskopomuc, CT. Plankton community shifted to smaller forms eight years after alewife introduction, but reversed back to larger species after large alewife winter die-off.Growth and survival of larval fishes: roles of competition and zooplankton abundance.

Welker, M.T., C.L. Pierce, and D.H. Wahl. 1994. Transactions of the American Fisheries Society 123:703-717.

Study assessed growth and survival of gizzard shad and bluegill at different population and food densities.

Gizzard shad survival and growth were negatively correlated with gizzard shad density and positively correlated with macrozooplankton prey.Bluegill growth was positively correlated with prey availability.

A-6 Appendix Westman, J. R. and R. F. Nigreli. 1955. Preliminary studies of menhaden and their mass mortalities in Long Island and New Jersey Waters. N.Y. Fish Game J. 2:142-153.

The effects of natural winter stresses on the mortality of the eastern gizzard shad, Dorosoma cepedianum, in Lake Erie. White, A. M., F. D. Moore, N. A. Alldridge, and D.M. Loucks. 1986. Report 78. Detailed analysis of gizzard shad mortality from cold stress. Study provides detailed information related to past winter die-offs, behavior of gizzard shad during cold stress, physiological response, and ability to predict winter kill and identify causes of mass mortality.

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