ML042790512
ML042790512 | |
Person / Time | |
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Site: | Browns Ferry ![]() |
Issue date: | 05/27/2004 |
From: | Hickman G Tennessee Valley Authority |
To: | Office of Nuclear Reactor Regulation |
References | |
Download: ML042790512 (25) | |
Text
Sport Fishing Index (SFI)
A Method to Quantify Sport Fishing Quality By Gary D. Hickman Tennessee Valley Authority Aquatic Biology Laboratory Norris, TN 37828 (865) 632-1791 Fax (865) 632-1693 gdhickman@tva.gov Key Words: Sport Fishing Quality Index Fishing Success Proportional Stock Density Relative Weight
Author Biosketch Gary D. Hickman B.S. University of Arkansas M.S. University of Arkansas Certified Fisheries Scientist by American Fisheries Society Present Employer: Tennessee Valley Authority Aquatic Biology Laboratory Norris, TN 37828 (865) 632-1791 Fax (865) 632-1693 gdhickman@tva.gov
Title:
Principal Environmental Scientist 2
Abstract A team of biologists, including representatives from TVA and state fishery resource agencies in the Tennessee River Valley, developed an index to quantify sport fishing quality for individual sport fish species. The objective of the Sport Fishing Index (SFI) is to provide the fishing public with information that will assist them in selecting locations that have the best potential for a successful fishing experience for the species they prefer. Additionally, the index provides biologists with a reference point measure of the quality of that fishery. Comparison of population sampling parameters and creel results for a particular sport fish species with expectations of these parameters from a high quality fishery (reference conditions) allows determination of fishing quality. To date, indices developed include largemouth, smallmouth, and spotted bass; crappies (black and white combined); walleye; sauger; and channel catfish.
Each SFI relies on measurements of quantity and quality aspects of angler success and fish population characteristics. Comparison of index results among reservoirs and between years from Tennessee and Cumberland River reservoirs from 1996 through 1998 indicated that differences in fishing quality for a particular species were measurable.
Introduction One of the most common questions asked by the fishing public: In the general area where I live, where do I have the best opportunity of experiencing a quality fishing trip for the species I most like to catch? The question is not easy to answer because the definition of quality differs with individual anglers. Fishery managers have spent numerous hours and dollars trying to provide this information.
Generally, fishery managers survey existing sport fish communities at least on an annual basis, using a variety of sampling techniques, depending on the species, size group of interest, and time of year. They also monitor fishing success and pressure via creel surveys. The problem then becomes how to pool the information and get the results to the fishing public in a readily understood manner.
Colvin and Vasey (1986) developed a method of qualitatively assessing crappie populations in Missouri reservoirs based on fall trap nets samples. Aspects measured included population density, growth rate, age structure, size structure, and recruitment. They did not include any measurement of angler success or fishing pressure expended for crappie. However, they were able to rate reservoir crappie populations based on a system of assigning point values (1-10) for each parameter, with an overall rating obtained by summing attained values.
The Tennessee Valley Authority (TVA) initiated a reservoir monitoring program in 1990 to evaluate the health of the reservoir ecosystem, and to examine how well each reservoir met the swimmable and fishable goals of the Clean Water Act (Dycus and Meinert, 1993).
Measurements of five indicators of reservoir health included: dissolved oxygen, chlorophyll, sediment quality, benthic macroinvertebrate community quality, and fish community quality.
This information was distributed to the public through an annual publication entitled RiverPulse. However, numerous responses from the public indicated that they also desired a measure of sport fishing quality. As a result, TVA assembled a multi-agency team of fishery 4
biologists (representatives from each state fishery management organization, universities, and TVA) to develop a method of assessing sport fishing quality in TVA reservoirs.
The objective of the Sport Fishing Index (SFI) team was to develop a multi-metric index capable of measuring sport fishing quality for individual species in specific Tennessee Valley reservoirs. The team evaluated several parameters that were calculated from creel surveys and population samples. The best and easily attainable ones were selected for inclusion as metrics for the index. The goal of the team was to develop an SFI that would provide anglers with information that help them select the best reservoirs for the species they prefer to catch.
Methods State fishery management agencies (Alabama Department of Conservation; Georgia Department of Natural Resources; Kentucky Department of Fish and Wildlife Resources; Mississippi Department of Wildlife, Fish, and Parks; and the Tennessee Wildlife Resources Agency) and TVA provided valuable data used in the calculation of the SFI. Data from creel surveys and standard population samples (electrofishing, trap netting, and experimental gill netting) were used. Results of each of these data sets were further separated into quantity and quality components (Figure 1). The SFI is calculated by comparing values for selected quantity and quality parameters from creel and population samples, to expected values that would occur in a good or high quality fishery. Point values are assigned to the parameters (up to 15 maximum per parameter) with higher points for higher quality fisheries. An overall SFI is 5
obtained by summing the point values (60 possible) that were assigned to each of the quantity and quality parameters.
Quantity--Capture rates of each species from creel surveys and population samples were assumed to be indicators of fish abundance, and therefore were used as quantity measures.
Angler catch rates were calculated from anglers who indicated that they were directing their efforts for the species in question. The population sampling methods and size groups used to calculate capture rates are given in Table 1. In the SFI, higher capture rates indicated a better quality fishery.
When developing an SFI for black bass (largemouth, smallmouth, and spotted combined),
capture rates for anglers fishing bass tournaments (catch per day per tournament angler) were used to supplement black bass angler catch rates (catch per hour) observed during general creel surveys. These data were obtained through state bass tournament information programs (BITE in Tennessee and BAIT in Alabama) which annually collect tournament catch information from local, regional and national bass tournaments held in the respective state. Although bass tournament results did not account for fish that were caught and released, tournament data did provide information useful in determining the general quality of the black bass fishery, especially when standard creel results were unavailable. When both data sets are available, each set was weighted equally. Otherwise, only the available data set was used.
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Tournament results could not be used to calculate individual bass species SFI values as tournament data was generally not broken down to the species level. In the general creel, distinctions were not made between species targeted, therefore fishing pressure reported for each bass species was the same.
Also for black bass species, either state agency or TVA electrofishing results were used for population parameters. Electrofishing capture rates were generally higher for state agency samples due to the different purposes of the sampling efforts between the two groups. TVA samples targeted the entire fish community, whereas state biologists actively sought only black basses in their samples. Consequently, a different set of catch rate scoring criteria were needed for each type of electrofishing sampling (Table 2). State electrofishing results were used if available, otherwise TVA results were used.
Quality--Quality measurements were determined by assessing the amount of effort anglers exerted towards a species and by the quality of the population as determined from looking at five different aspects of the population samples. Consequently, more parameters were included in the quality components of the index than the quantity components. Fishing pressure directed towards the target species as measured from creel surveys was used as a measure of fishing quality. This is based on the assumption that as fishing success improves for a particular species, the amount of effort expended for that species will also increase. However, we recognized that, by itself, fishing pressure could not always be compared among lakes and used as a measure of fishing quality, because higher pressure also was apparent on lakes that were 7
near population centers. When combined with high angler catch rates for a specific species, angling pressure for that species can be representative of fishing quality. Additionally, population characteristics as measured from standard population samples supplemented the determination of fishery quality (Figure 1).
Population quality is based on measurement of five aspects of each resident sport fish community, with each aspect making up 20 percent of the overall population quality rating (Table 3). These aspects include four which address size structure (proportional number of fish in each length group) of the community as described by Anderson (1980) and Gablehouse (1984): Proportional Stock Density (PSD), Relative Stock Density of Preferred-sized fish (RSDP), Relative Stock Density of Memorable-sized fish (RSDM), and Relative Stock Density of Trophy-sized fish (RSDT). Composition of resident fish populations with an adequate size structure is reflective of the quality of that particular fishery. Relative weight (Wr), a measure of average condition of individual fish (Anderson, 1980), makes up the fifth population quality aspect. The size-group used for Wr determination for each species includes stock through preferred as described by Gablehouse (1984). This group generally supports the majority of a particular fishery. In the case of largemouth bass, 200 to 380 mm (10 to 15 inches) fish are used, for crappie, fish between 130 and 250 mm (5 to 10 inches) in total length are used. Fall length-weight measurements were used when available for Wr calculations to minimize variation often present during other seasonal periods.
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Calculations--Comparison of actual results to expectations for a high quality fishery allows determination of fishing quality for a particular sport fish species in each reservoir. Expectations (reference conditions) for parameters were derived by two different methods. Expectations or reference conditions for angler catch rates, fishing pressure, and population sample catch rates were derived by trisecting the range of values obtained during state fish and wildlife agency or TVA fish sampling results (zero to 95 percent of the range of observed scores) from 1990 to 1995 for Tennessee and Cumberland River mainstream and tributary reservoirs (Table 2). Use of this technique requires inclusion of a full range from high to low quality fisheries for each sport fish species in Tennessee and Cumberland River reservoirs during these years. Criteria for population quality aspects (PSD, RSDP, RSDM, RSDT, and Wr) were based on recognized standards for development of a multi-species fishery as described by Gablehouse (1984) (Table 3).
Observed values were compared to reference ranges and assigned a corresponding numerical value. Each of the four components (angler success quantity and quality, and population quantity and quality) were given a maximum attainable value of 15 (Tables 2 and 3). A score of 5 represented less than desirable or poor conditions, 10 for marginal, and 15 for good or excellent conditions. In order to equally weigh the five parameters making up the population quality component, scores are adjusted to allow for a maximum parameter score of 15, i.e.,
each aspect assigned a maximum score of 3 (Table 3). It should be noted here that individual population quality parameters are scored separately, i.e., a population can receive a high score for PSD (3) while at the same time receiving a low score for RSDP (1) and a moderate score 9
for RSDM (2). The resident population structure, through comparison with appropriate reference ranges, determines each assigned score. When individual parameters were missing, available parameters were adjusted to equal the total points possible for that component. For example, if bass tournament information was available but bass creel catch rate was not, the tournament data was adjusted to a maximum of 15 points instead of 7.5. The four component values were summed for individual species to obtain the Sport Fish Index (SFI) value for that species.
Using this approach, the maximum SFI score is 60 and the minimum is 20. When only creel or population data are available, the SFI value is calculated by summing the scores for quantity and quality from the existing data and multiplying by two.
When population density of a particular sport fish species in a reservoir was so low that not enough individuals were captured to reliably determine proportional densities or relative weights, then that species received a low score for that parameter. A technique described by Weithman et al. (1980) was used to determine if sample size was large enough to accurately (90 percent confidence) categorize PSD and RSD estimates into standard groups (i.e. PSD=0-39, 40-60,61-100). This was accomplished by comparison of the number of quality length fish within a sample of stock length individuals. Populations with relatively low or high PSD values required fewer individuals sampled to obtain a reliable estimate than those with moderate values.
Weithman et al. (1980) noted that a maximum of 100 fish will always provide a reliable estimate 10
of PSD. A minimum of 10 individuals within the appropriate size ranges were required to obtain a representative Wr sample.
Results Sport fishing index results for Tennessee and Cumberland River reservoirs during 1996 through 1998 are shown in Tables 4 and 5. The average SFI rating for each species for all Tennessee and Cumberland reservoirs with data available for calculations is included for comparative purposes. Results usually followed expectations. Reservoirs that were generally considered to be high quality by both anglers and biologists for a particular species scored high; and those that were considered poor for a particular sport fish species usually scored low.
Using black bass as an example, Figure 2 displays the capability of the SFI to distinguish the wide range of fishery quality available in reservoirs in both Tennessee and Cumberland River systems. Results were similar for other sport fish species. Sample variation between years at individual reservoirs was relatively low over the three-year sample period. A majority of SFI scores (>75%) varied 10 points or less. Larger variances could generally be explained by shifts in the quality of particular fisheries. For example, the black bass SFI in Cherokee Reservoir revealed an apparent steady decline in bass fishery quality over the three-year period from 1996-1998 (SFI scores of 52, 46, 31, respectively). This is born out by examination of electrofishing catch rate and proportion of the population made of preferred sized bass (RSDP) over this time period at Cherokee. Catch rates for bass declined while the proportion of the 11
population made up of larger individuals increased, indicating poor recruitment to the fishery (Figure 3).
In order to make the information readily available and understandable to the angling community and regulatory agencies, graphs are used to show annual SFI results for individual species or species groups (Figure 4). Anglers use the graphs to focus their efforts on reservoirs with the highest quality fisheries for a particular species during a particular year. The SFI graphs also provide for comparisons between fishery quality among a series of reservoirs. Graphs of individual sport fish species are generated for publication in local magazines and pamphlets, and are used in permit compliance documentation where appropriate.
In recent years, SFI information has been used to describe the quality of the resident fishery in conjunction with compliance monitoring and other regulatory issues at two TVA nuclear plants.
SFI was used during operational monitoring in the vicinity of Watts Bar Nuclear Plant (Baxter, 1998), in support of a thermal variance request at Sequoyah Nuclear Plant (TVA, 1996), and in the Environmental Assessment for the Watts Bar Nuclear Plant Supplemental Condenser Cooling Water Project (TVA, 1998). In each of these instances the SFI provided information showing high quality fisheries for sauger, the most likely sport fish species to be adversely impacted as a result of plant operation. This information, along with other information regarding potential for adverse impacts, was instrumental in renewing operational permits at both Watts Bar and Sequoyah nuclear plants.
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Conclusions The Sport Fishing Index was able to measure differences between reservoir fishing quality for individual species and species groups. Comparison of individual lake results with an overall average SFI for all lakes that particular year provides another indicator for both anglers and biologists. The SFI index has also been used successfully in a regulatory setting.
Anglers find the index a helpful source of information for determining those lakes that are typically productive for the species of fish they prefer to catch. When anglers experience poor success in a particular lake, they can refer to the relevant SFI to determine if the fishing quality for the species sought was typically low, or had declined over previous years.
State biologists have found that the SFI is useful in making resource management decisions.
The inclusion of both population quantity and quality aspects with angler catch rates and fishing pressure on a particular reservoir can give biologists a more comprehensive appraisal of the fishery.
Agency cooperation is important to maximize quality of the results and minimize costs of data collection. Pooling of multiple state resource and federal agency information enhances the index through coverage of a larger number of reservoirs; therefore, a more thorough index with a wider range of indicator conditions can be developed.
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References Anderson, R. O. 1980. Proportional stock density (PSD) and relative weight (Wr):
interpretive indices for fish populations and communities. In S. Gloss and B. Shupp (eds.) Practical fisheries management: more with less in the 1980s. New York Cooperative Fishery Research Unit, Ithaca, New York. 27-33.
Baxter, D. S. 1998. Aquatic environmental conditions in the vicinity of Watts Bar Nuclear Plant during two years of operation, 1996-1997. Tennessee Valley Authority, Water Management, Chattanooga, TN. 259 pp.
Colvin, M. A. and F. W. Vasey. 1986. A method of qualitatively assessing white crappie populations in Missouri reservoirs. In G. E. Hall and M. J. Van Den Avyle (eds.)
Reservoir Fisheries Management Strategies for the 80s. American Fisheries Society, Bethesda, Maryland. 79-85.
Dycus, D. L. and D. L. Meinert. 1993. Reservoir monitoring, monitoring and evaluation of aquatic resource health and use suitability in Tennessee Valley Authority reservoirs.
Tennessee Valley Authority, Water Resources, Chattanooga, Tennessee, TVA/WM -
93/15.
Gablehouse, D. W., Jr. 1984. A length-categorization system to assess fish stocks. North American Journal of Fisheries Management 4(3):273-285.
Tennessee Valley Authority. 1996. A supplemental 316(a) demonstration for alternative thermal discharge limits for Sequoyah Nuclear Plant, Chickamauga Reservoir, Tennessee. Tennessee Valley Authority, Engineering Laboratory, Norris, TN.
WR96-1-45-145. 87 pp.
Tennessee Valley Authority. 1997. Watts Bar Nuclear Plant supplemental condenser cooling water project draft environmental assessment. Tennessee Valley Authority, Engineering Laboratory, Norris, TN. 53 pp.
Weithman, A. S., J. B. Reynolds, and D. E. Simpson. 1980. Assessment of structure of largemouth bass stock by sequential sampling. Proceedings of the Annual Conference Southeastern Association of Fish and Wildlife Agencies 33(1979):415-424.
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Table 1. Population sampling methods and size groups used to calculate capture rates.
Species Sampling Method Size Groups Unit of Measure Largemouth bass Electrofishing >200 Number Per Hour Smallmouth bass Electrofishing >180 Number Per Hour Spotted bass Electrofishing >150 Number Per Hour Black & White crappie Trap Netting >130 Number Per Net Night Sauger Exp. Gill Netting >200 Number Per Net Night Walleye Exp. Gill Netting >250 Number Per Net Night Channel Catfish Exp. Gill Netting >280 Number Per Net Night
Table 2. Sport Fish Index population quantity and creel quantity and quality metrics and scoring criteria.
Metrics Scores Black Bass Population - Quantity 5 10 15 TVA Electro. catch/hour <15 15 - 31 >31 State Electro. catch/hour <62 62 - 124 >124 Creel - Quantity 2.5 each 5 each 7.5 each Anglers catch/hour <0.3 0.3 - 0.6 >0.6 BAIT & BITE data <1.1 1.1 - 2.3 >2.3 Creel - Quality 5 10 15 Pressure (hours/acre) <8 8 - 16 >16 Largemouth Bass 1
Population - Quantity 5 10 15 TVA Electro. catch/hour <13 13 - 25 >25 State Electro. catch/hour <53 53 - 106 >106 Creel - Quantity 5 10 15 Anglers catch/hour <0.29 0.29 - 0.58 >0.58 Creel - Quality 5 10 15 Pressure (hours/acre) <8 8 - 16 >16 Smallmouth Bass Population - Quantity 5 10 15 TVA Electro. catch/hour <4 4-8 >8 State Electro. catch/hour <8 8 - 15 >15 Creel - Quantity 5 10 15 Anglers catch/hour <0.1 0.1 - 0.3 >0.3 Creel - Quality 5 10 15 Pressure (hours/acre) <8 8 - 16 >16 Spotted Bass Population - Quantity 5 10 15 TVA Electro. catch/hour <5 5 - 11 >11 State Electro. catch/hour <14 14 - 27 >27 Creel - Quantity 5 10 15 Anglers catch/hour <0.07 0.07 - 0.13 >0.13 Creel - Quality 5 10 15 Pressure (hours/acre) <8 8 - 16 >16 Crappie Population - Quantity 5 10 15 Trap Net catch/net night <4 4-7 >7 Creel - Quality 5 10 15 Anglers catch/hour <0.6 0.6 - 1.2 >1.2 Creel - Quantity 5 10 15 Pressure (hours/acre) <6 6 - 12 >12
Table 2 (continued)
Sauger Population - Quantity 5 10 15 Exp. Gill Net catch/net night <9 9-17 >17 Creel - Quantity 5 10 15 Anglers catch/hour <0.5 0.5 - 1 >1 Creel - Quality 5 10 15 Pressure (hours/acre) <5 5 - 10 >10 Walleye Population - Quantity 5 10 15 Exp. Gill Net catch/net night <5 5 - 11 >11 Creel - Quantity 5 10 15 Anglers catch/hour <0.2 0.2 - 0.4 >0.4 Creel - Quality 5 10 15 Pressure (hours/acre) <5 5 - 10 >10 Channel Catfish Population - Quantity 5 10 15 Exp. Gill Net catch/net night <2 2-4 >4 Creel - Quantity 5 10 15 Anglers catch/hour <0.3 0.3 - 0.7 >0.7 Creel - Quality 5 10 15 Pressure (hours/acre) <9 9 - 19 >19 1
TVA electrofishing only used when state agency electrofishing data is unavailable.
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Table 3. Sport Fish Index population quality metrics and scoring criteria.
Scores Metrics 5 10 15 Population - Quality 1 2 3 PSD <20 or >80 20-39 or 61-80 40-60 RSDP (preferred) 0 or >60 1-9 or 41-60 10-40 RSDM (memorable) 0 or >25 1-4 or 11-25 5-10 RSDT (trophy) 0 <1 >1 Wr (Stock-Preferred <90 >110 90-110 size fish) 18
Table 4. Sport fishing index values (minimum 20, maximum 60) for black basses; largemouth, smallmouth, and spotted bass (1996-1998)
Black Bass Largemouth Bass Smallmouth Bass Spotted Bass Reservoir 1996 1997 1998 1996 1997 1998 1996 1997 1998 1996 1997 1998 Cumberland Mainstream Cordell Hull 38 34 28 28 40 42 Old Hickory 40 48 34 30 47 31 30 Cheatham 43 43 46 46 Barkley 44 40 39 49 40 43 22 Cumberland Tributary Dale Hollow 33 42 23 34 38 57 31 42 Great Falls 32 42 30 42 24 Center Hill 39 47 40 29 40 32 40 52 30 45 59 41 Percy Priest 40 50 38 40 50 41 40 30 36 40 30 38 Tennessee Mainstream Fort Loudoun 43 39 37 33 41 32 30 32 30 25 Watts Bar 48 42 39 43 44 26 35 27 39 34 27 31 Chickamauga 45 37 41 47 39 37 25 25 20 41 25 37 Nickajack 44 40 35 42 42 37 20 25 20 33 27 34 Guntersville 36 42 37 32 42 42 35 40 35 Wheeler 47 36 37 34 44 34 48 44 26 32 20 Wilson 31 42 42 44 40 42 20 24 Pickwick 51 37 37 44 34 34 42 58 42 20 24 Kentucky 31 34 33 30 32 34 24 30 29 32 34 26 Tennessee Tributary Watauga 41 38 25 35 35 29 50 46 38 South Holston 41 37 36 30 35 30 46 37 45 Boone 39 44 39 36 36 38 46 42 50 Fort Patrick 34 32 30 28 34 Cherokee 52 46 31 57 50 29 36 32 20 30 22 Douglas 36 44 40 31 41 40 20 Tellico 41 33 38 33 33 32 33 25 44 35 25 22 Norris 27 27 32 23 24 25 28 25 35 34 27 36 Melton Hill 28 34 35 28 32 30 20 20 20 20 20 Chatuge 40 32 24 38 20 20 20 40 46 34 Nottely 20 24 20 24 20 20 20 26 Blue Ridge 20 20 30 Hiwassee 32 26 40 28 42 26 40 24 Woods 40 47 34 47 30 Tims Ford 32 23 29 20 45 25 25 Normandy 44 40 38 40 33 36 35 30 45 45 50 Other Reelfoot 30 30 30 32 AVERAGE 38.7 37.4 34.5 35.2 37.3 32.7 34.9 33 33.1 34.7 31.2 30.3 19
Table 5. Sport fishing index values (minimum 20, maximum 60) for crappie (black and white combined), walleye, sauger, and channel catfish (1996-1998).
Crappie Walleye Sauger Channel Catfish Reservoir 199 199 1998 199 1997 199 199 199 199 199 199 199 6 7 6 8 6 7 8 6 7 8 Cumberland Mainstream Cordell Hull Old Hickory 20 35 30 20 27 20 30 Cheatham 20 30 Barkley 30 36 46 Cumberland Tributary Dale Hollow 25 30 30 Great Falls Center Hill 25 25 50 40 32 30 26 Percy Priest 40 35 41 20 36 Tennessee Mainstream Fort Loudoun 30 30 35 33 33 30 Watts Bar 30 36 44 33 32 30 25 Chickamauga 30 30 39 27 36 30 Nickajack 20 30 20 20 20 Guntersville 24 40 54 42 45 Wheeler 34 Wilson 20 20 20 20 Pickwick 48 44 20 24 Kentucky 38 49 52 25 30 31 20 25 Tennessee Tributary Watauga 20 20 45 46 34 25 30 South Holston 26 30 27 50 20 34 20 30 30 Boone 32 30 27 20 Fort Patrick 30 Cherokee 34 36 36 35 40 27 25 37 Douglas 36 46 46 35 38 38 20 Tellico 25 30 20 20 20 20 26 Norris 20 36 36 20 32 24 20 30 22 22 Melton Hill 20 40 Chatuge 30 20 24 20 20 30 Nottely 30 20 28 50 40 40 Blue Ridge 20 20 Hiwassee 20 20 20 Woods 20 40 20 Tims Ford 20 25 32 20 20 Normandy 30 40 20 24 20 20 35 20 30 Other Reelfoot 60 50 20 AVERAGE 28.3 33.6 39.1 31.4 27.3 28.0 30.7 30.5 34.6 26.0 25.6 27.4 20
Quantity Parameters Quality Parameters Angler Success Sampling CPUE Angling Pressure Species Population PSD RSDP RSDM RSDT Wr Figure 1. Parameters used to calculate the Sport Fishing Index (SFI).
60 maximum 75th percentile median th 25 percentile 55 minimum 50 45 SFI Score 40 35 30 25 20 1996 1997 1998 Figure 2. Comparison of SFI scores from all sites during 1996-1998.
200 40 180 35 160 30 140 Electrofishing Catch Per Hour 25 120 RSDP Score 100 20 80 15 60 10 40 5
20 0 0 1995 1996 1997 1998 Figure 3. Electrofishing catch per hour for black bass from Cherokee Reservoir during 1995-1998 with Relative Stock Density of Preferred-sized (RSDP) bass.
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Cheatham Wilson Barkley Guntersville Percy Priest Douglas Boone Nickajack Chickamauga Normandy Wheeler Pickwick Kentucky Tellico Reelfoot Ft. Loudoun Center Hill Old Hickory South Holston Melton Hill Watauga Average Cherokee Hiwassee Ft. Patrick Henry Cordell Hull Watts Bar Norris Nottely Tims Ford Chatuge 0 10 20 30 40 50 60 SFI Score Figure 4. Comparison of largemouth bass scores for selected reservoirs during 1998.
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