ML17222A777

Annual Environ Operating Rept for 1988.

ML17222A777
Person / Time
Site:	Saint Lucie
Issue date:	12/31/1988
From:	APPLIED BIOLOGY, INC.
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ML17222A775	List: ML17222A774 ML17222A776 ML17222A777
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AB-596, NUDOCS 8905020323
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APPLIED BIOLOGY, INC. AB-596 FLORIDA POWER & LIGHT COMPANY ST. LUGIE UNIT 2 ANNUAL ENVIRONMENTALOPERATING Rf PORT 1988 8905 oaosm 8~0~>7 ~

PDR *DDCItl, 05000389 PNU R

2968 A NORTH DECATUR ROAD 'TLANTA, GEORGIA 30033 404-296-3900

AB-596 FLORIDA POWER & LIGHT COMPANY ST. LUCIE UNIT 2 ANNUAL ENVIRONMENTAL OPERATING REPORT 1988 APRIL 1989 FLORIDA POWER 5 LIGHT COMPANY JUNO BEACH, FLORIDA APPLIED BIOLOGY, INC.

ATLANTA, GEORGIA

ENVIRONMENTAL OPERATING REPORT p>>

TABLE OF CONTENTS Pa(ac TABLE OF CONVERSION FACTORS FOR METRIC UNITS- 111 EXECUTIVE

SUMMARY

iv Introduction iv Turtle Nesting Survey iv Intake Canal Monitoring v Other Related Activities- v INTRODUCTION-

Background

Area Description Plant Description T URTLES- 6 I ntroduction 8 Materials and Methods 11 Nesting Survey 11 Intake Canal Monitoring 12 Studies to Evaluate and/or Mitigate Intake Entrapment -- - 15 Light Screen to Minimize Turtle Disorientation - - - - 16 Results and Discussion- 16 N esting Survey 16 Distribution of Loggerhead Nests Along Hutchinson Island 16 Estimates of Total Loggerhead Nesting on Hutchinson I sl and 20 Temporal Loggerhead Nest'ing Patterns- 22 Predation on Loggerhead Turtle Nests 23 Green and Leatherback Turtle Nesting 24 Intake Canal Monitoring 26 Relative Abundance and Temporal Distribution --- 26 Size-Class Distl ibutions 29 S ex Ratios 32 Capture Efficiencies Relative Condition - -- 33 35 Mortalities- 37 R ecapture Incidents 40 S umma ry ~ \WW WW W W 41 LITERATURE CITED- 46 FIGURES 53 TABLES 75

TABLE OF CONVERSION FACTORS FOR METRIC UNITS To convert Multi 1 b To obtain centigrade (degrees) ('C x 1.8) + 32 fahrenheit (degrees) centigrade (degrees) 'C + 273.18 kelvin (degrees) centimeters (cm) 3.937 x 10-1 inches centimeters(cm) 3.281 x 10"2 feet centimeters/second (cm/sec) 3.281 x 10"2 feet per second cubic centimeters (cm3) 1.0 x103 1 i ters grams (g) 2.205 x 10-3 pounds grams (g) 3.527 x 10-2 ounces (avoirdupois) hectares (ha) 2.471 acres kilograms (kg) 1.0 x 103 grams kilograms (kg) 2.2046 pounds kilograms (kg) 3.5274 x 101 ounces (avoirdupois) kilometers (km) 6.214 x 10-1 miles (statute) kilometers (km) 1.0 x 106 millimeters liters (1) 1.0 x 103 cubic centimeters (cm3) liters (1) 2.642 x 10"1 gallons (US liquid) meters (m) 3.281 feet meters (m) 3.937 x 101 inches meters (m) 1.094 yards microns (p) 1.0 x 10-6 meters milligrams (mg) 1.0 x 10 3 grams milligrams/liter (mg/1) 1.0 parts per million milliliters (ml) 1.0 x 10-3 liters (US liquid) millimeters (mm) 3.937 x 10-2 inches millimeters (mm) 3.281 x 10"3 feet square centimeters (cm2) 1.550 x 10-1 square inches square meters (m2) 1.076 x 101 square feet square millimeters (mm2) 1.55 x 103 square inches

EXECUTIVE

SUMMARY

INTRODUCTION The St. Lucie Plant is an electric generating station on Hutchinson Island in St. Luci e County, Florida. The plant consists of two nuclear-fueled 850-MW units; Unit 1 was placed on-line in March 1976 and Unit 2 in May 1983. This document has been prepared to satisfy the requirements contained in the United States Nuclear Regulatory Commission's Appendix B Environmental Protection Plan (EPP) to St. Lucie Unit 2 Facility Operating License No. NPF-16. This report discusses environmental pro-tection activities related to sea turtles as requi red by Subsection 4.2 of the EPP.

TURTLE NESTING SURVEY There have been considerable year-to-year fluctuations in sea turtle nesting "activity on Hutchinson Island since monitoring began in 1971.

Low nesting activity in 1975 and 1981 - 1983 in the vicinity of the power plant was attributed to construction of plant intake and discharge struc-tures. Nesting returned to normal or above normal levels following both periods of construction. Power plant operation exclusive of construction has had no significant effect on nesting near the plant. Data collected through.1988 have shown no long-term reductions in total nesting, total emergences or nesting success on the island. Formal requirements to con-duct. this program expired in 1986 but were voluntarily continued in 1988 with agreement from federal and state agencies.

INTAKE CANAL MONITORING Since plant operation began in 1976, 1,929 sea turtles (including 83 recaptures) representing five different species have been removed from the intake canal. Eighty-five percent of these were loggerheads.

Differences in the numbers of turtles found during different months and years were attributed to natural variation in the occurrences of turtles in the vicinity of the plant, rather than to any influence of the plant itself. The majority of turtles removed from the intake canal (about 93 percent) were captured alive and released back into the ocean. Turtles confined between the AlA barrier net and intake headwalls usually resided in the canal for a relatively short period of time, and most were in good to excellent condition when caught.

OTHER RELATED ACTIVITIES The 'integrity. of a vegetative light screen along the dune line at the St. Luci e Plant is assessed on a continuing basis. During 1988, routine inspections of the screen were made and replantings conducted as needed.

Studies to evaluate various intake deterrent systems, as required by the NRC's Unit 2 Environmental Protection Plan, were conducted during 1982 and 1983. Results and evaluations of those studies were presented to regulatory agencies during 1984, and the requi rement is now considered completed.

INTRODUCTION BACKGROUND This document has been prepared to satisfy the requirements con-tained in the United States Nuclear Regulatory Commission's (NRC)

Appendix B Envi ronmental Protection Plan to St. Lucie Unit 2 Facility Operating License No. NPF-16.

In 1970, Florida Power 8 Light Company (FPL) was issued Permit No.

CPPR-74 by the United States Atomic Energy Commission, now the Nuclear Regulatory Commission, that allowed construction of Unit 1 of the St.

Luci e Plant, a'n 850-MW nuclear-powered electric generating station on Hutchinson Island in St. Luci e County, Fl orida.

~ St. Luci e Plant Unit

~ 1 was placed on-line in March 1976. In May 1977, FPL was issued Permit No.

CPPR-144 by the NRC for the construction of a second 850-MW nuclear-powered unit. Unit 2 was placed on-line in May 1983 and began commercial operation in August, of that year.

St. Lucie Plant Units 1 and 2 use the Atlantic Ocean as a source of water for once-through condenser cooling. Since 1971, the potential environmental effects resulting from the intake and discharge of this water have been the subject of FPL-sponsored biotic studies at the site.

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Baseline environmental studies of the marine environment adjacent to the St. Lucie Plant were described in a series of reports published by the Florida Department of Natural Resources (Camp et al., 1977; Futch and Dwinell, 1977; Gallagher, 1977; Gallagher and Hollinger, 1977; Worth and Hollinger, 1977; Hoffler and Van Breedveld, 1979; Tester and Steidinger, 1979; Walker 1979; Walker et al., 1979; Walker and Steidinger, 1979).

The results of Unit 1 operational and Unit 2 preoperational biotic moni-toring at the St. Lucie Plant were presented in six annual reports (ABI,

. 1977, 1978, 1979, 1980a, 1981b, 1982) . In January 1982, a National Pollutant Discharge Elimination System (NPDES) permit was issued to FPL by the U.S. Environmental Protection Agency (EPA). The EPA guidelines for the St. Lucie site biological studies

~ were based on the document entitled "Proposed St.~ Lucie Plant 'Preoperational and Operational Biological Monitoring Program - August 1981" (ABI, 1981c).

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Findings from these studies were reported in three annual reports (ABI, 1983, 1984a, 1985a). The EPA biotic monitoring requirements were deleted from the NPDES permit in 1985.

Jurisdiction for sea turtle studies is with the NRC, which is con-sidered to be the lead federal agency relative to consultation under the Endangered Species Act. Previous results dealing exclusively with sea turtle studies are contained in five envi ronmental operating reports (ABI, 1984b, 1985b, 1986, 1987, 1988). This report describes the 1988 environmental pr otection activities related to sea turtles, as required by Subsection 4.2 of the St. Lucie Plant Unit 2 Environmental Protection Plan.

AREA DESCRIPTION The St. Lucie Plant is located on a 457-ha site on Hutchinson Island on Florida's east coast (Figures I and 2). The plant is approximately midway between the Ft. Pierce and St. Lucie Inlets. It is bounded on its east side by the Atlantic Ocean and on its west side by the Indian River Lagoon.

Hutchinson Island is a barrier island that extends 36 km between inlets and obtains its maximum width of 2 km at the plant site. Eleva-tions approach 5 m atop dunes bordering the beach and decrease to sea level in the mangrove swamps that are common on much of the western side.

Island vegetation is typical of southeastern Florida coastal areas; dense present at the higher elevations, and mangroves abound at the lower ele-vations. Large stands of black mangroves, including some on the plant site, have been killed by flooding for mosquito control over past decades.

The Atlantic shoreline of Hutchinson Island is composed of sand and shell hash with intermittent rocky promontories protruding through the beach face along the southern end of the island. Submerged coquinoid rock formations parallel much of the island off the ocean beaches. The ocean bottom immediately offshore from the plant site consists primarily of sand and shell sediments. The unstable substrate limits the establishment of rooted macrophytes.

The Florida Current, which flows parallel to the continental shelf margi n, begins to diverge from the coastline at West Palm Beach. At Hutchinson Island, the current is approximately 33 km offshore. Oceanic water associated with the western boundary of the current periodically meanders over the inner shelf, especially during summer months.

PLANT DESCRIPTION The St. Lucie Plant consists of two 850-NW nuclear-fueled electric generating units that use nearshore ocean waters for the plant's once-through condenser cooling water system. Water for the pl ant enters through three submerged intake structures located about 365 m offshore (Figure 2). Each of the intake structures is equipped with a velocity

' cap to minimize fish entrainment. ~ Horizontal intake velocities are less than 30 cm/sec. ~ From the intake structures, the water passes through submerged pipes (two 3.7 m and one 4.9 m in diameter) under the beach and dunes that lead to a 1500-m long intake canal. This canal transports the water to the plant. After passing through the plant, the heated water is discharged into a 670-m long canal that leads to two buried discharge pipelines. These pass underneath .the dunes and beach and along the ocean floor to the submerged discharges, the first. of which is approximately 365 m offshore and 730 m north of the intake.

Heated water leaves the first di scharge line from a Y-shaped nozzle (diffuser) at a design velocity of 396 cm/sec. This high-momentum jet entrains ambient water resulting in rapid heat dissipation. The ocean depth in the area of the first discharge is about 6 m. Heated water

leaves the second discharge line through a series of 48 equally spaced high velocity 'jets along a 323-m manifold (multiport diffuser). This diffuser starts 168 m beyond the first discharge and terminates 856 m from shore. The ocean depth at discharge along this diffuser is from about 10 to 12 m. As with the first diffuser, the purpose of the second diffuser is to entrain ambient water and rapidly dissipate heat. From the points of discharge at both diffusers, the warmer water rises to the surface and forms a surface plume of heated water. The plume then spreads out on the surface of the ocean under the influence of wind and currents and the heat dissipates to the atmosphere.

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, TURTLES The NRC's St. Luci e Unit 2 Appendix B Environmental Protection Plan issued April 1983 contains the following technical specifications:

4.2 Terrestrial/A uatic Issues Issues on endangered or threatened sea turtles raised in the Unit 2 FES-OL f.NRC, 1982j and in the Endangered Species Biological Assessment (March 1982) I'.Bellmund et al., 1982] will be addressed by programs as follows:

4;2;1 Beach Nestin Surve s Beach nesting surveys for all species of sea turtles will be conducted on a yearly basis for the period of 1982 through 1986. These surveys will be con-ducted during the nesting season from approximately mid-April through August.

The Hutchinson Island beach will be divided into 36 one-km-long survey areas. In addition, the nine 1.25-km-long survey areas used in previous studies (1971-1979) will be maintained for comparison pur-poses. 'urvey areas will be marked with numbered wooden plaques and/or existing landmarks.

The entire beach will be surveyed seven days a week.

All new nests and false crawls will be counted and recorded in each area. After counting, al 1 crawl tracks wil 1 be obliterated to avoid recounting.

Predation on nests by raccoons or other predators will be recorded's it occurs. Records will be kept of any seasonal changes in beach topography that may affect the suitability of the beach for nesting.

4-2.2 Studies to Evaluate and/or Miti ate Intake A program that employs light and/or sound to deter turtles from the intake structure will be conducted.

The study will determine with laboratory and field experiments if sound and/or light will result in a reduction of total turtle entrapment rate.

The study shall be implemented no later than after the final removal from the ocean of equipment and

0,

structures associated with construction of the third intake structure and the experiments shall terminate 18 months later. .Four months after the conclusion of the experimental period, a report on the results of the study will be submitted to NRC, EPA, National Marine Fisheries Service (NMFS), and the U.S. Fish and Wildlife Service (USFWS) for their evaluation.

If a statistically significant reduction in annual total turtle entrapment rate of 80 percent or greater can be demonstrated, using the developed technology and upon FPL receiving written con-currence by NRC, EPA, NMFS, and USFWS then permanent installation of the deterrent system shall be completed and functioning no later than 18 months after the agencies'oncurrence. The design of this study needs to take into account the significant annual variation in turtle entrapment observed in the past.

If an 80 percent reduction of turtle entrapment can-not'e projected to all three intake structures, then an interagency task force composed of NRC, EPA, NMFS, USFWS, and FPL shall convene 18 months after completion of the third intake and determine if other courses of action to mitigate and/or reduce turtle entrapment are warranted (such as physical barrier, emergence of new technology or methods to deter turtles).

4.2.3 Studies to Evaluate and/or Miti ate Intake Alternative methods or procedures for the capture of sea turtles entrapped in the intake canal will be evaluated. If a method er procedure is considered feasible and cost effective and may reduce capture mortality rates, it will be field tested in the intake canal.

4.2.4 Li ht'creen to Minimize Turtle Disorienta-tion fNOTE: This is al,so Section 4.2 of the NRC St.

Luci e Unit 1 Appendix B Technical Specifications issued May 1982]

Australian pine or other suitable plants (i.e.,

native vegetation such as live oak, native figs, wild tamarind and others) shall be planted and main-tained as a light screen, along the beach dune line bordering the plant property, to minimize turtle di so ri entati on.

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4.2.5 Ca ture and.Release Pro ram Sea turtle removal from the intake canal wi 11 be conducted on a continuing basis. The turtles will be captured with large mesh nets, or other suitable nondestructive device(s), if deemed appropriate. A formalized daily inspection, from the shoreline, of the capture device(s) will be made by a qualified individual when the device(s) are deployed. The turtles will be identified to species, measured, weighed (if appropriate), tagged and released back into the ocean. Records of wounds, fresh or old, and a subjective judgement on the condition of .the turtle (e.g.,'arnacle coverage, underweight) will be maintained. Methods of obtaining additional biological/physiological data, such as blood analy-ses and parasite loads, from captured sea turtles will be pursued.. Dead sea turtles wi 11 be subjected to a gross necropsy, if found in fresh condition.

INTRODUCTION Hutchinson Island, Florida, is an important rookery for the loggerhead turtle, Caretta caretta, and also supports some nesting of the dh1 l ~d, d h 1 h h k <<1 . ~h coriacea (Caldwell et al., 1959; Routa, 1968; Gallagher et al., 1972; Worth and Smith, 1976; Williams-Walls et al., 1983). All three species are protected by state and federal statutes. The federal government d

classifies the loggerhead turtle as a threatened species. The leather-back turtle and the Florida nesting population of the green turtle are listed by the federal government as endangered species. Because in world populations of marine turtles resulting from coastal of'eductions development and fishing pressure (NMFS, 1978), maintaining the vitality of the Hutchinson Island rookery is important.

It has been a prime concern of FPL that the construction and sub-sequent operation of the St. Lucie Plant would not adversely affect the Hutchinson Island rookery. Because of this concern, FPL has sponsored monitoring of marine turtle nesting activity on the island since 1971.

Daytime surveys to quantify nesting, as well as nighttime turtle tagging programs, wer e conducted in odd numbered years from 1971 through 1979. During daytime nesting surveys, nine 1.25-km-long survey areas were monitored five days per week (Figure 3). The St. Lucie Plant began operation in 1976; therefore, the first three survey years (1971, 1973 and 1975) were preoperational. Though the power plant was not operating during 1975, St. Luci e Plant Unit No. 1 ocean intake and discharge struc-tures were installed during that year. Installation of these structures included construction act i vi ti es conducted offshore from and pe rpen-dicular to the beach. Construction had been completed and the plant was in full operation during the 1977 and 1979 surveys.

A modified daytime nesting survey was conducted in 1980 during the preliminary construction of the ocean discharge structure for St. Lucie Plant Unit 2. During this study, four of the previously established r

1.25-km-long sur vey areas were monitored. Additionally, eggs from turtle nests potentially endangered by construction activities were relocated.

Every year from 1981 through 1988, thirty-six 1-km-long survey areas comprising the entire island were monitored seven days a week during the nesting season (Figure 3). The St. Lucie Plant Unit 2 discharge struc-

i ture was installed during the 1981 nesting season. Offshore and beach construction of the Unit 2 intake structure proceeded throughout the 1982 nesting season and was completed near the end of the 1983 season.

Construction activities associated with installation of both structures were similar to those conducted when Unit 1 intake and discharge struc-tures were installed. Eggs from turtle nests potentially endangered by construction activities were relocated during all three years.

Requirement 4.2.1 of the NRC's St. Lucie Unit 2 Appendix B Environmental Protection Plan was completed with submission of the 1986 nesting survey data (ABI, 1987). The nesting survey was continued volun-tarily through 1988 with agreement from federal and state agencie's.

Results are presented in this report and discussed in relation to pre-

~

vious findings.~

In addition to monitoring sea turtle nesting activities and relo-cating nests away from plant construction areas, monitoring of turtles in the intake canal has been an integral part of the St. Luci e Plant environmental monitoring program. Turtles entering the ocean intake structures are rapidly transported with cooling water through the intake pipes and into the enclosed canal system where they are entrapped. Since the plant became operational in 1976, turtles entrapped in the intake canal have been captured, measured, tagged and returned to the ocean..

Previous publications and technical reports have presented findings of the nesting surveys, nest relocation activities and canal capture 10

program (Gallagher et al., 1972; Worth and Smith, 1976; ABI, 1978, 1980a, 198la, 1982, 1983, 1984b, 1985b, 1986, 1987; Williams-Walls et al., 1983; Prof fitt et al., 1986; Ernest et al., 1988; Martin et al., 1987).

Results of studi es to assess the ef fects of thermal di scharges on hatchling swimming speed have also been reported (ABI, 1978; O'ara, 1980) . The purpose of this report is to 1) present 1988 sea turtle nesting survey data and summarize observed spatial and temporal nesting patterns since 1971, 2) document and summarize predation on turtle nests since 1971, and 3) present 1988 canal capture data and summarize related data collected since 1976.

MATERIALS AND METHODS Methodol ogi es used during previ ous turtl e nesting surveys on Hutchinson Island were described by Gallagher et al. (1972), Worth and Smi th (1976) and ABI (19'78, 1981a, 1982, 1987, 1988) . Methods used during the 1988 survey were designed to allow comparisons with these pre-vious studies.

From 18 April through 9 September 1988, daily nest surveys were con-ducted along Hutchinson Island from the Ft. Pierce Inlet south to the St.

Lucie Inlet. Several additional surveys were conducted after 9 September to confirm that nesting had ceased, the last survey being conducted on 20 September. Bi ol ogi sts used smal 1 of f-road motorcyc1 es to survey the island each morning. New nests, non-nesting emergences (false crawls),

and nests destroyed by predators were recorded for each of the thirty-six I

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1-km-long survey areas comprising the entire island (Figure 3). The nine 1.25-km-long survey areas established by Gallagher et al. (1972) also were monitored so comparisons could be made with previous studies.

During the daily nest monitoring, any major changes in topography that may have affected the beach's suitability for nesting were recorded.

In addition, each of the thirty-six 1-km-long survey areas has been systematically analyzed and categorized based on beach slope (steep, moderate, etc.), width from high tide line to the dune, presence of benches (areas of abrupt vertical relief) and miscellaneous charac-teristics (packed sand, scattered rock, vegetation on the beach, exposed roots on the primary dune, etc.).

In a cooperative effort, the Florida Department of Natural Resources (DNR) was notified of all green turtle nests. Eggs from some of these nests were collected as part of the Florida DNR Headstart Program.

Additionally, data from stranded turtles found during beach surveys were routinely provided to the National Marine Fisheries Service through the Sea Turtle Stranding and Salvage Network.

Intake Canal Monitorin Routine capture of sea turtles from the St. Lucie Plant intake canal continued during 1988. Turtles were. removed from the canal with large-mesh tangle nets fished between the intake headwalls and a barrier net located at the Highway A1A bridge (Figure 2). These nets were usually deployed on Monday morning and retrieved on Friday afternoon.'o detect 12

captures, formal daily inspections of the nets (mornings and afternoons) were made each day of deployment.

Various sizes, numbers and locations of tangle nets have been used to date as capture techniques have been refined. Nets in recent use were from 32 to 61 m in length, 2.7 to 3.7 m in depth and 30 to 40 cm in stretch mesh. Large floats kept the nets at the surface, and because nets were not weighted with lead lines, turtles which became entangled remained at the water's surface until removed.

The barrier net at the A1A bridge is intended to confine turtles to the easternmost section of the intake canal, where capture techniques have been most effective. However, the integrity of the barrier net occasionally has been compromi sed, and turtles have been able to swim over or under it. Prior to December 1986, most turtles circumventing the barrier net eventually emerged in the intake wells of Units 1 and 2 (Figure 2), where they were retrieved by means of large mechanical rakes or specially designed nets. However, during 1986, a security intrusion barrier was constructed across the north-south arm of the intake canal.

After its emplacement, turtles larger than 30.5 cm in carapace width were impeded from reaching the intake wells by a large-mesh chain net. Tangle nets were set west of the A1A barrier net to capture these turtles.

Turtles smaller than 30 5 cm can pass through the mesh of both the barrier net and the intrusion barrier.

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Personnel of Applied Biology, Inc. were on call 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> a day to retrieve captured turtles fr'om both the intake wells and turtle nets.

The utmost care was taken in handling captured turtles to prevent injury or trauma.

After removal from the canal, turtles were identified to species, measured, weighed, tagged, examined for overall condition (wounds, abnor-malities, parasites, etc.) and released back into the ocean. Although both straight-line and curved carapace lengths were measured, only straight-line measurements were used in analyses presented in this report. Straight-line carapace length (SLCL) was measured from the pre-central scute to the notch between the postcentral scutes (mi nimum cara-pace length of Pritchard et al., 1983).

Since 1982, blood samples have been collected and analyzed to i nvestigate the potential occurrence and significance of anemia in cap-tured animals and to determi ne the sex of immature turtles. Blood was removed from the paired dorsal cervical sinuses of subject turtles using the technique described by Owens and Ruiz (1980). A small subsample of whole blood was hemolyzed and hemoglobin measured in grams per 100 ml by colorimetry using an A.O. 1010D hemoglobinometer. The remainder of the blood sample was centrifuged for 15 minutes to separate cells and serum.

Sex determinations were subsequently made by researchers at Texas A 8 H University using radioimmunoassay for serum testosterone (Owens et al.,

During 1984 and 1985, blood cell samples were also provided to the National Marine Fisheries Service for the purpose of developing and refining methods for use in conducting turtle stock analysis.

Si ck or injured tur tl es were treated and occas i onal ly hei d for observation prior to release. When treatment was warranted, injections of antibiotics and vitamins were administered by a local veterinarian.

Resuscitation techniques were used if a turtle was found that appeared to have died recently. Beginning in 1982, necropsies were conducted on dead turtles found in fresh condition; no necropsies were performed during 1988.

Florida Power 8 Light Company and Applied Biology, Inc. continued to assist other sea turtle researchers in 1988. In addition to the Florida DNR's Headstart Program, data, specimens and/or assistance have been given to the National Marine Fisheries Services, U.S. Army Corps of q

O Engineers, Resources Smithsonian Di vi sion, Institution, Center fo r Sea South Carolina Wildlife Turtl e Research and Marine (Uni ve rs i ty of Florida), Texas A 8 M University, University of Rhode Island, University of South Carolina, University of Illinois, University of Georgia and the Western Atlantic Turtle Symposium.

Studies to Evaluate and/or Miti ate Intake Entra ment A program that assessed the feasibility of using light and/or sound to deter turtles from entering the St. Lucie Plant intake structures was conducted in 1982 and 1983 and completed in January 1984. As required, test results and evaluations were written up and a presentation was made to the NRC, National Marine Fisheries Service and the Florida Department of Natural Resources on 11 April 1984. ~ Requirement 4.2.2 ~ ~ of the NRC's St. Lucie Unit.2 Appendix Environmental Protection Plan is considered

~

~ B completed with submission of deterrent study findings.~

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Li ht Screen to Minimize Turtle Disorientation A vegetative beach dune light screen created to minimize turtle disorientation at the St. Lucie Plant was routinely inspected by FPL per-sonnel during 1988. Replantings were conducted as required to maintain its integrity.

RESULTS AND DISCUSSION

~N Distribution of Lo erhead Nests Alon Hutchinson Island When sea turtle nesting surveys began on Hutchinson Island, nine 1.25-km-long survey areas were used to estimate loggerhead nesting acti-vity for the entire island. Since 1981, all 36 1-km-long segments comprising the island's coastline have been surveyed. Regardless of technique, loggerhead nest densities have shown considerable annual variation within individual survey areas (Figures 4 and 5). Yet, the annual spatial distribution of those nests among survey areas has pro-duced a rather uniform gradient, nest densities consistently increasing from north to south (ABI, 1987). The gr adi ent appears to be linear when only the nine 1.25-km-long survey areas are used (Figure 4), but becomes non-linear when all 36 1-km-long survey areas are included in the analy-sis (Figure 5). During 1988 the distribution of loggerhead nests along the island followed the same general pattern as previously reported, nest densities increasing abruptly from north to south along the northern por-tion of the island, reaching maximum densities in central survey areas and then decreasing slightly toward the southern portion of the island (Figure 5).

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In the past, the pronounced gradient observed on the northern end of the island was occasionally influenced by physical processes occurring there; periods of heavy accretion reduced the gradient, while periods of erosion accentuated it (Worth and Smith, 1976; Williams-Walls et al.,

1983) . However, during recent years no cons i stent rel ations hip was apparent when field observations of beach widths were compared to the spatial distribution of nests along the island (ABI, 1987). Thus, even though beach dynamics may sometimes affect the selection of nesting sites by loggerhead turtles, other factors must also contribute to the selec-tion process. Offshore bottom contours, spatial distribution of nearshore reefs, type and extent of dune vegetation, and degree of human activity on the beach at night have been identified as some of the fac-tors affecting nesting (Caldwell, 1962; Hendrickson and Balasingam, 1966; Bustard, 1968; Bustard and Greenham, 1968; Hughes, 1974; Davi s and Whiting, 1977; Mortimer, 1982). Relationships between spatial nesting patterns and specific environmental conditions are often difficult to establish because of the interrelationship of the factors involved.

Not all ventures onto the beach by a female turtle culminate in suc-cessful nests. These "false crawls" (non-nesting emergences) may occur for many reasons and are commonly encountered at other rookeries (Baldwin and Lofton, 1959; Schulz, 1975; Davis and Whiting, 1977; Talbert et al.,

1980; Raymond, 1984). Davis and Whiting (1977) suggested that relatively high percentages of false crawls may reflect disturbances or unsatisfac-tory nesting beach characteristics. Therefore, certain factors may affect a turtle's preference to emerge on a beach, while other factors 17

may affect a turtle's tendency to nest after it has emerged. An index which relates the number of nests to the number of false crawls in an area is useful in estimating the post-emergence suitability of a beach for nesting. In the present study this index is termed "nesting success" and is defined as the percentage of total emergences that result in nests.

Historically, the pattern of loggerhead emergences on the island has paralleled the distribution of nests (ABI, 1987, 1988), and this same trend was apparent in 1988 (Figure 6). In contrast, nesting success by loggerheads along the island has typically lacked gradients (Figure 7).

Thus, the relatively high numbers of loggerhead nests usually observed along the southern half of the island have resulted primarily from more turtles coming ashore in that area rather than from more preferable nesting conditions being encountered by the turtles after they emerged.

Hughes (1974) and Bustard (1968) found that loggerheads preferred beaches adjacent to outcrops of rocks or subtidal reefs. Williams-Walls et al. (1983) suggested that the nesting gradient on Hutchinson Island may be influenced by the offshore reefs if female turtles concentrate on the reef s cl osest to the beach to rest or feed. The proximi ty of offshore reefs would put the greatest concentration of turtles near the southern half of the island where coincidentally nesting is highest.

Loggerhead nesting densities during 1988 were generally within the range of values previously recorded (Figures 4 and 5). Several excep-18

0 tions were related to changes in beach conditions. Record high nesting in Area E coincided with very low nesting in Area F. This apparent shift in nesting from Area F to Area E may be explained by the removal of con-siderable beachfront vegetation in Area F between the 1986 and 1987 nesting seasons. Baldwin and Lofton (1959) indicated that nesting turtles show a preference for beaches backed by high dunes or vegetation and a hesitancy to emerge on barren beaches. Since the removal of vege-tation in Area F, emergence rates have been the lowest ever recorded in this area (Figure 6; ABI, 1988).

Record low loggerhead nesting in Area CC during 1988 (Figure 5) was apparently due to considerable erosion in this area. During the 1988 nesting season, beaches were observed to be extremely narrow in Area CC.

Though emergence rates were within the range of previously observed values (Figure 6), nesting success was extremely'ow (Figure 7) ~

Apparently, unsuitable beach conditions were not detected by turtles until after they had emerged onto the beach in Area CC.

Numbers of loggerhead emergences and consequently nest densities remained relatively low in Area Z from 1981 through 1987 (ABI, 1988).

Since this area included a large public beach access, a motel and con-siderable artificial lighting, nighttime human activity may have deterred turtles from coming ashore. Reported reductions in beachfront lighting in this area may explain record high nesting and emergence rates in this area during 1988 (Figures 5 and 6).

19

Nesting surveys on Hutchinson Island were initiated in response to.

concerns that the operation of the St. Luci e Plant might negatively impact the 1 ocal sea turtl e rookery. Previ ous analyses, using 1 og-1 ikel i hood tests of independence (G-test; Sokal and Rohl f, 1981) demonstrated that the construction of the plant's offshore intake and discharge structures significantly reduced nesting at the plant site during construction years (1975, 1981, 1982 and 1983; Proffitt et al.,

1986; ABI, 1987). However, nesting at the plant consistently returned to l evels similar to or greater than those at a control site in years following construction (Figure 8). Thus, power plant operation exclusive of intake/discharge construction had no apparent effect on nesting.

Data collected through 1988 have shown no long-term reduction in loggerhead nest densities, total emergences or nesting success in either the nine 1.25-km-long survey areas or the 36 1-km-long survey areas (Table 1; Figure 9).

Estimates of Total Lo erhead Nestin on Hutchinson Island Various methods were used during surveys prior to 1981 to estimate the total number of loggerhead nests on Hutchinson Island based on the number of nests found in the nine 1.25-km-long survey areas (Gallagher et al., 1972; Worth and Smith, 1976; ABI, 1980a). Each of these methods were subsequently found to consistently overestimate island totals (ABI, 1987). Since whole-island surveys began in 1981, it has been possible to determine the actual, proportion of total nests deposited in the nine This has then allowed extrapolation from the nine survey areas to

~

areas. ~

the entire island for years prior to 1981.

20

From 1981 through 1988 the total number of nests in the nine areas varied from 33.1 to 35.6 percent of the total number of nests on the island (Table 1). This is. slightly higher than the 31.3 percent which would be expected based strictly on the proportion of linear coastline comprised by the nine areas. Using the ei'ght-year mean of 34.0 percent, estimates of the total number of nests on Hutchinson Island can be calcu-lated by multiplying the number of nests in the nine areas by 2.94. This technique, when applied to the nine survey areas during the eight years in which the entire island was surveyed, produced whole-island estimates within five percent of the actual number of nests counted. Because the proportion of nests recorded in the nine survey areas remained relatively constant over the last eight years, this extrapolation procedure should provide a fairly accurate estimate of total loggerhead nesting for years prior to

~

1981.~

It is clear that loggerhead nesting activity on Hutchinson Island fluctuates considerably from year to year (Table 1). Annual variations in nest densities also are common at other rookeries (Hughes, 1976; Davis and Whiting, 1977; Ehrhart, 1980) and may result from the overlapping of non-annual breeding populations. During tlie last seven years, however, annual nest production has remained relatively high. Total nesting acti-vity was greatest during 1986 when 5,483 loggerhead nests were recorded on the island. During 1988, 4,990 nests were counted. No relationships between total nesting activity and power plant operation or intake/discharge construction were indicated by year-to-year variations in total nesting on Hutchinson Island.

21

Tem oral Lo erhead Nestin Patterns The loggerhead turtle nesting season usually begins in early May, when ocean temperatures reach 23'o 24'C, attains a maximum during June or July, and ends by late August or early September (ABI, 1987). Nesting activity during 1988 followed this same pattern (Figure 10). Shifts in the temporal nesting pattern on Hutchinson Island may be influenced by fluctuations in water temperature. This was observed during 1975 and 1982 when early nesting in April coincided with average ocean tem-peratures above 24'C (ABI, 1983; Williams-Walls et al., 1983).

Cool water intrusions frequently occur over the continental shelf of southeast Florida during the summer (Taylor and Stewart, 1958; Smith, 1982). Worth and Smith (1976), Williams-Walls et al. (1983) and ABI (1982, 1983, 1984b, 1985b, 1986, 1987, 1988) suggested that these intru-sions may have been responsible for the tempo ary declines in loggerhead turtle nesting activity previously observed on Hutchinson Island.

Similarly, a substantial decrease in nesting during late July 1988 was apparently due to an intrusion of cool water (Figure 10).

Though natural fluctuations in temperature have been shown to affect temporal nesting patterns on Hutchinson Island, there has been no indica-tion that power plant operation has affected these temporal patterns (ABI, 1988).

22

Predation on Lo erhead Turtle Nests Since nest surveys began in 1971, raccoon predation probably has been the major cause of turtle nest destruction on Hutchinson Island.

Researchers at other locations have reported raccoon predation levels as high as 70 to nearly 100 percent (Davis and Whiting, 1977; Ehrhart, 1979; Hopkins et al., 1979; Talbert et al,, 1980). Raccoon predation of loggerhead turtle nests on Hutchinson Island has not approached this level during any study year, though levels for individual 1.25-km-long areas have been as high as 80 percent (Figure 11). Overall predation rates for survey years 1971 through 1977 were between 21 and 44 percent, with the high of 44 percent recorded in 1973. A pronounced decrease in raccoon predation occurred after 1977, and overall predation rates for the nine areas have not exceeded 10 percent since 1979. A decline in predation rates on Hutchinson Island has been variously attributed to trapping programs, construction activities, habitat loss and disease (Williams-Walls et al., 1983; ABI, 1987).

During 1988, five percent (250) of the loggerhead nests (n=4,990) on the island were depredated by raccoons. As in previous years (ABI, 1987, 1988), predation of turtle nests was primarily restricted to the most undeveloped portion of the island (i.e., Areas E through U) and the southernmost areas (Areas II and JJ; Figure 12).

Ghost crabs have been reported by numerous researchers as important predators of sea turtle nests

~

(Baldwin and Lofton, 1959; Schulz, 1975; Di amond, 1976; Fowl er, 1979; Hopkins et al .,

~ 1979; Stancyk, 1982) .

23

Though turtle nests on Hutchinson Island probably have been depredated by ghost crabs since nesting surveys began in 1971, this source of nest destruction did not become apparent until 1983. guantification of ghost crab predation was initiated the same year.

Overall predation rates by ghost crabs have varied from 0.3 to 2.1 percent from 1983 - 1987 (ABI, 1988). During 1988,.0.2 percent (9) of the loggerhead nests (n=4,990) on the island were destroyed by ghost crabs (Figure 12). Nests destroyed by a combination of raccoon and ghost crab predation have been included as raccoon predations in previous discussions. When these combination predations are included as crab pre-dations, the overall predation rates by ghost crabs range from 0.4 to 3.2 ghost crabs or a combination of ghost crabs and raccoons.

Green and Leatherback Turtle Nestin Green and leatherback turtles also nest on Hutchinson Island, but in bablyly fewer numbers than loggerhead turtles. Prior to 1981, both survey (nine 1.25-km-long sections) and .inter-survey areas were monitored for the pre-sence of green and leatherback nests. Thirty-one kilometers of beach from Area 1 south to the St. Lucie inlet were included in that effort.

During whole island surveys from 1981 through 1988, only two of 134 leatherback nests and only five of 424 green nests were recorded on the five kilometers of beach north of Area 1. Therefore, previous counts of green and leatherback nests within the 31 kilometers surveyed were pro-not appreci ably di ffe rent from total dens it i es fo r the entire 24

island. Based on this assumption, green and leatherback nest densities may be compared among all survey years, except 1980, when less than 15 kilometers of beach were surveyed.

Prior to 1988, the number of nests observed on the island ranged from 5 to 72 for green turtles and from 1 to 20 for leatherbacks (Figure 13). During the 1988 survey, 74 green turtle and 33 leatherback turtle nests were recorded on Hutchinson Island.

Temporal nesting patterns for these species differ from the pattern for loggerhead turtles. Green turtles typically nest on Hutchinson Island from mid-June through the first or second week of September.

During 1988, green turtles nested from 14 June through 15 September.

Leatherback turtles usually nest on the island from mid-April through early to mid-July. During 1988 this species nested from 26 March through 26 June.

Considerable fluctuations in green turtle nesting on the island have occurred among survey years (Figure 13). This is not unusual since there are drastic year-to-year fluctuations in the numbers of green turtles nesting at other breeding grounds (Carr et al., 1982). Despite these fluctuations, green turtle nesting has remained relatively high during the last seven years (1982 through 1988) and may reflect an increase in the number of nesting females in the Hutchinson Island area. During 1988, green turtles nested most frequently along the southern half of the island. This is consistent with results of previous surveys.

25

Leatherback turtle nest densities have remained low on Hutchinson Island; however, increased nesting during recent years (Figure 13) may reflect an-- overall increase in the number of nesting females in the Hutchinson Island area. During 1988, leatherback turtles primarily nested on the southern half of the island.

Intake Canal Monitorin Entrainment of sea turtles at the St. Lucie Plant has been attri-buted to the presumed physical attractiveness of the offshore structures housing the intake pipes rather than to plant operating characteristics (ABI, 1980b and 1986). Even when both units are operating at full capa-city, turtles must actively swim into one of the intake pipes before they encounter current velocities sufficiently strong to effect entrainment.

Consequently, a turtle's entrapment relates primarily to the probability that it will detect and subsequently enter one of the intake structures.

Assuming that detection distances do not vary appreciably over time and that all turtles (or a constant proportion) are equally attracted to the structures, capture rates will vary proportionately to the number of turtles occurring in the vicinity of the structures. If this assumption is true, data from the canal capture program should reflect natural variability in the structure of the population being sampled.

Relative Abundance and Tem oral Distribution During 1988, 181 -sea turtle captures took place in the intake canal of the St. Lucie Plant (Table 2). Three of the five species of sea turtles occurring in coastal waters of the southeastern United States 26

i were represented in the catches, including 134 loggerheads, 42 greens and 5 Kemp's ridleys. Since intake canal monitoring began in Hay 1976, 1,631 loggerhead (including 82 recaptures), 269 green (including 1 recapture),

8 leatherback, 6 hawksbill and 15 Kemp's ridley captures have been reported from the St. Lucie Plant.

Annual catches of loggerheads increased steadily from a low of 33 in 1976 (partial year of plant operation and monitoring) to 173 in 1979 (Figure 14). After declining between 1979 and 1981, yearly catches of loggerheads again rose steadily, reaching a high of 195 during 1986.

Captures have declined about 30 percent over the last two years.

Two offshore intake structures were in place prior to Unit 1 start-up s

in 1976; the thi rd

~

and 1 a rgest structure was instal 1 ed during 1982-1983. Even though all three structures are in relatively close proximity, the addition of another pipe may have increased the probabil-ity of a turtle being entrained. Because this change cannot be quan-tified, data collected prior to 1982 may not be comparable with that collected after 1983. Additionally, the influence of the construction itself on sea turtle entrainment during 1982 and 1983 is unknown. With these considerations in mind, neither a long-term increase nor decrease in the number of loggerheads captured at the St. 'ucie Plant can be inferred from the data-.

During 1988, the monthly catch of 1 oggerheads ranged from 2 (October) to 30 (June), with a monthly mean of 11.2 (+9.2; Table 3).

27

Captures during May and June were higher than during any previous year, while. captures during January, August and October were much lower than average (Figure 15). Over the entire monitoring period, monthly catches have ranged from 0 to 39; the greatest number of captures occurred during January 1983.

When data from all full years of monitoring (1977-1988) were com-b ined, the highest number of loggerhead captures occurred in January (12.5 percent); fewest captures were recorded in November and December (Table 3). However, monthly catches have shown considerable annual variability. Months having relatively low catches one year often have had relatively high catches in another.

Catches of green turtles also have varied widely among years, rangi ng from 0 in 1976 (partial year of sampling) to 69 in 1984 (Table 4). During 1988, 42 individuals were captured. The average annual catch of green turtles, excluding 1976, was 22.4 (+23.8). A t-test (Sokal and Rohlf, 1981) applied to annual capture data indicates significantly (P<0.05) more captures from 1983 - 1988 than during the preceding six year period (Figure 14). This suggests a long-term increase in the number of green turtles inhabiting the nearshore coastal area adjacent to the plant. Again, however, the influence of the addition of a third intake pipe in 1982 on capture trends is not known.

Green turtles have been caughtduring every month of the year, with average monthly catches for all years combined ranging from 0 4 in 28

September to 7.5 in January (Table 4). However, seasonal abundance pat-terns of greens are much more pronounced than for loggerheads, about 74 percent of all captures occurring between November and March. During 1988, the largest number of greens (12) were captured in January. The most greens ever caught in one month was 37 in January 1984.

Catches of leatherbacks, hawksbil ls and Kemp's ridl eys have been infrequent and scattered throughout the eleven year study period (Table 2). Each species has shown rather pronounced seasonal occurrences; all but one of the eight leatherbacks were collected between February and May, five of the six hawksbills were collected between June and September, and all but one of the 10 Kemp's ridleys were caught between November and April.

Size-Class Distributions To date, loggerheads removed from the intake canal have ranged in length (SLCL) from 40.4 to 125.0 cm (x = 65.8 + 12.9 cm) and in weight from 10.9 kg to 154.7 kg (Figures 16 and 17). About 72 percent of all loggerheads captured. were 70 cm or less in length and weighed less than 50 kilograms.

A carapace length of 70 cm approximates the smallest size of nesting loggerhead females observed along the Atlantic east coast (Hirth, 1980).

However, adults can only be reliably sexed on external morphological characteristics (e.g., relative tail length) after obtaining a length of about 80 cm. Based on these divisions, data were segregated into three 29

i groups: juvenile/sub-adults (<70 cm; the demarcation between these two components is not well established in the literature), adults (>80 cm) and transitional (70-80 cm). The latter group probably includes some mature and some immature individuals. Of the 1,535 captur'es for which length data were collected, 72 percent were juveniles/sub-adults, the majority of these measuring between 50 and 70 cm SLCL (Table 5). Adults accounted for about 16 percent of all captures, the remaini'ng 12 percent comprised of animals in the transitional size class. Similar size-frequency distributions, indicating a preponderance of juveniles, have been reported for the Mosquito/Indian River Lagoon (Mendonca and Ehrhart, 1982), the Canaveral ship channel (Henwood, 1987), and Georgia and South Carolina (Hillestad et al., 1982). These data suggest that coastal waters of the southeastern United States constitute an important develop-mental habitat for Caretta caretta.

Seasonal patterns of abundance for various size classes indicated that juveniles and sub-adult loggerheads were slightly more abundant during the wi nter than at other times of the. year (Table 5). About 36 percent of juvenile/sub-adult loggerheads were captured between January I

and March. Abundances decreased in spring and remained relatively constant during the summer and early fall before decreasing again to lowest levels in November and December. The seasonal distribution of adult loggerheads was much more pronounced, 56 percent of all captures occurring between June and August. This represents the period of peak nesting on Hutchinson Island. If other nesting months are included (May and September), 75 percent of all adults were captured during the nesting

~

season.

30

i Green turtles removed alive from the intake canal over the entire study period ranged in size from 20 to 108 cm SLCL (x = 35.6 + 14.1 cm) and 0.9 kg to 177.8 kg (Figures 18 and 19). Nearly all (96 percent) were juveniles or sub-adults. About 80 percent were 40 cm or less in length, and 66 percent weighed less than 5 kilograms. These immature turtles exhibited distinct winter pulses suggesting migratory behavior (Table 4).

However,'ome immature green turtles were present throughout the year.

To date, only seven adult green turtles (SLCL >83 cm; Witherington and Ehrhart, 1987) have been removed from the canal; all were captured during or shortly after the nesting season.

The six hawksbills removed from the canal ranged in size from 34 to 70 cm SLCL (x = 44.7 + 13.0 cm) and in weight from 6.4 to 52.2 kg (x =

16.3 + 17.7 kg) . All but one were juveniles (SLCL <53 cm; Hi rth, 1980);

Similarly, all but one of the 15 Kemp's ridleys captured at the St. Lucie Plant were juveniles (SLCL <60.0 cm; Hi rth, 1980). Carapace lengths for the ridleys ranged from 27.0 to 62.0 cm SLCL (x = 35.2 + 9.1 cm) and weights from 3.2 to 31.8 kg (x = 7.3 + 7.8 kg). The eight leatherbacks removed from the canal ranged in length from 112.5 to 150 cm, and at least six were adults (SLCL >121 cm; Hirth, 1980). The largest leather-back for which an accurate weight was obtained, a male with a SLCL of 134.5 cm, weighed 233.6 kg.

31

i Sex Ratios Since intake canal monitoring began in 1976, 245 adult loggerheads have been sexed. The smallest was 75.5 cm in length and was observed nesting on Hutchinson Island subsequent to her capture in the canal.

Females predominated males by a ratio of 5.4:1.0, which significantly 2

departs from a 1: 1 ratio (X , P<0.05). Consequently, temporal patterns in the number of adult loggerhead captures are heavily influenced by the numbers of females present. When sexes were separated, it is evident that males were relatively evenly distributed among months, whereas over 80 percent of the females were taken during the nesting season (May through September; Figure 20).

The number of adult loggerheads captured at the St. Lucie Plant increased appreciably after 1982. Between 1977 and 1982, an average of 8.3 adult loggerheads (+4.1; range = 3-15) were entr apped each year, whereas over the last six years, an average of 32.2 adults per year

(+9.5; range = 19-43) were captured. This increase corresponds to a general rise in loggerhead nesting activity near the plant (Figure 21).

This associ ation is not unexpected, because increased nearshore movement associated with nesting behavior increases the probability of a turtle detecting one of the intake structures and hence the probability of entrainment. The addition of the third offshore intake structure, the largest of the three structures, in 1982 also may have contributed to increased entrainment of adults.

32

l 0

Between September 1982 and December 1986, 267 individual juvenile and sub-adult loggerhead turtles captured in the canal were sexed by Texas A 5 M University researchers using a bioimmunoassay technique for blood serum testosterone. For the purpose of these analyses, Dr. Owens and his associates used 76 cm as the cutoff length between immature and adult turtles. Bioimmunoassay results indicate that for immature loggerheads removed from the St. Lucie Plant intake canal, females out-I numbered mal es by a ratio of 2 3 1 0. The sex ratios of immature loggerheads captured in the Cape Canaveral ship channel (1.7:1.0) and the Indi an River Lagoon (1.4:1.0) are al so reported to be si gni fi cantly 2

skewed in favor of females (X , P<0.05; Wibbels et al., 1984). Blood samples collected since 1986 are currently being analyzed and these results will provide a valuable tool for assessing temporal variability in the sex ratios of the local loggerhead population.

Of the seven adult green turtles captured since monitoring began, five were males and two were females. Six immature green turtles have been sexed through blood work; all have been females. Of the five adult leatherback turtles for which sex was recorded, two were females and three were males. The adult hawksbill and Kemp's ridley were both fema-les. No sex information exists for juveniles of these species.

Ca ture Efficiencies Capture methodologies evolved over the first several years of intake canal monitoring as net materials, configurations and placement were varied in an effort to minimize sea turtle entrapment times.

33

Concurrently, alternative capture techniques were evaluated and potential deterrent systems tested in the laboratory. During this period, capture effici enci es varied in relation to netting effort and the effectiveness of the systems deployed.

A capture/recapture study conducted in the intake canal between October 1980 and January 1981 indicated that most turtles confined be-tween the A1A bridge and the intake headwalls were captured within two weeks of their entrainment (ABI, 1983). Based on more recent formal daily inspections, it appears that capture efficiencies have'urther improved. Host turtles entering the canal are now caught within a few days of first sighting, and in many instances, turtles have been caught in the tangle nets without any prior sighting, suggesting residency times of less than 24 hours. Better utilization of currents and eddies, adjustments to tethering lines and multi-net deployments have contributed to reduced'ntrapment times.

Entrapment times may be extended for turtles swimming past the A1A barrier net (ABI, 1987). Occasionally, 'the top of the net has been sub-merged or the anchor cable pulled free from the bottom, allowing larger turtles to pass; turtles with carapace widths less than about 30.5 cm can swim through the large mesh. Because capture efforts west of the AlA bridge have generally been less effective than those near the intake headwalls, most turtles breaching the barrier net were not caught until they entered the intake wells of Units 1 and 2. Since the canal capture program began, about 15 percent of all turtles entrapped in the canal 34

have been removed from the intake wells. Because of their relatively small sizes, a greater proportion of greens (48.7 percent) reached the-"

plant than loggerheads (8.6 percent).

After completion of the security intrusion barrier in December 1986, most turtles larger than 30.5 cm in carapace width were prevented from reaching the intake wells. During 1988, six loggerheads (4.5 percent of all loggerhead captures) breached the A1A barrier net, 'nd all were removed from the canal at the intrusion barrier. By comparison, a total of 23 green and four Kemp's ridleys (55 and 80 percent, respectively, of total captures) circumvented the A1A barrier net during 1988. All of the greens and two of the Kemp's ridleys were removed at the intake wells.

The two remaining Kemp's ridleys were captured at the intrusion barrier.

To maximize confinement of larger turtles to the easternmost section of the intake canal, and thereby increase overall capture efficiency, the A1A barrier net was periodically surveyed during 1988 and, as required, appropriate measures taken to ensure its integrity.

Relative Condition Turtles captured alive in the intake canal of the St. Lucie Plant were assigned a relative condition based on weight, activity, parasite infestation, barnacle coverage, wounds, injuries and any other abnor-malities which might have affected overall well-being (Table 6). During 1988, 91.8 percent (123) of all loggerheads found in the canal were alive and in good to excel-lent condition. Only 3.7 percent (5) of loggerhead of the loggerheads removed from the canal were dead.

35

~

~l

Of the 42 green turtles removed from the intake canal during 1988, 73.8 percent (31) were in good to excellent condition, while only 14.3 percent (6) were in fair or poor condition. Two green turtles (4.8 percent) were dead when removed from the canal. Relative condition was not recorded for the three remaining individuals (7.1 percent). Only one of the five ridleys caught during 1988 was in good to excellent con-dition. Two were in fair condition and two were dead.

Over the entire monitoring period, about 71 and 78 percent, respec-tively, of all loggerhead and green captures have involved turtles in good to excellent condition (Table 6). Captures of individuals in fair to poor condition have occurred about 21 percent of the time for logger-

, heads and 13 percent of the time for gr eens. All of the hawksbills and all but one leatherback have been removed from the canal in good to excellent condition. Although about half of the Kemp's ridleys have been in good to excellent condition, all categories have been represented in-the catches.

Relative condition ratings can be influenced by a number of factors, some related and others unrelated to entrainment and/or entrapment in the intake canal. Ratings of good to excellent indicate that turtles have not been negatively impacted by their entrapment in the canal, at least as evidenced by physical appearance. Although ratings of fair or poor imply reduced vitality, the extent to which entrainment/entrapment is responsible is often indeterminable. ~ In some instances, conditions responsible for lower ratings, such as injuries, obviously were sustained prior to entrainment.

~

~

36

During 1988, about 13 percent of all captures involved individuals with noticeable injuries, including missing appendages, broken or missing pieces of carapace or deep lacerations. However, nearly all of these were old, well-healed wounds. Shark attacks appeared to have been responsible for some of the injuries, as evidenced by crescent-shaped bite marks. Several other turtles had obvious propeller scars on the carapace. Many turtl'es removed from the canal during 1988 had one or more recent superficial abrasions to the carapace or skin, but only three individuals had injuries serious enough to require treatment. Two loggerheads had suffered recent damage to the posterior carapace, possibly the result of collisions with boats. Both were treated by a veterinarian and released the same day. Another loggerhead had a fishing lure embedded in the skin just below the eye. The hook was removed, ointment applied to the wound and the animal released. Additionally, a small green turtle removed from the intake wells had a wound to the head possibly resulting from contact with the mechanical rakes used to remove debris from the wells. It was also treated, held for observation and subsequently released.

Mortalities During 1988, 6 loggerhead mortalities (4.5 percent of all loggerhead captures) were recorded in the intake canal. All were removed from the security intrusion barrier. Two Kemp's ridley mortalities were also recorded in the vicinity of the intru'sion barrier during 1988.

Additionally, two small green turtles became tightly entangled in the turtle nets and drowned. ~ Attempts to revive these turtles by resuscita-tion were unsuccessful. ~

37

0 Over the entire 13 year monitoring period, 122 (7.5 percent) of the 1,631 loggerheads and 18 (6.7 percent) of the 269 green turtles entrapped in the canal were found dead (Table 6). Mortalities spanned the range of size classes for loggerheads (SLCL = 47.5-125 cm), while all green turtle

'ortalities involved juveniles less than 41 cm in length. The four Kemp's ridley mortalities documented at the plant during 1987 and 1988 were the only deaths for this species to date; no leatherback or hawks-bill mortalities have occurred at the St. Lucie Plant.

Mortalities have been closely monitored throughout the life of the canal capture program in an attempt to assign probable causes and take appropriate corrective measures to reduce future occurrences. Previous analyses of capture data identified drowning in nets, drowning in the intake pipes during periods of reduced intake flow, injuries sustained from dredging operations and injuries sustained from the mechanical rakes used in the intake wells as probable mortality factors (ABI, 1987).

Although difficult to quantify, the entrapment and subsequent demise of i njured or sick turtles probably accounts for a portion of observed mor-talities.

Over the'ears, materials and procedures have been modified to reduce the potential for a turtle drowning during capture. Lead lines have been removed from the nets and deployment techniques altered to allow turtles easier movement after entanglement. Surveillance of the nets has also increased. However, even with these precautions, a turtle

.has occasionally drowned. In recent years, this has occurred primarily 38

4 when a small turtle has become entangled with one or more larger indivi-duals, apparently restricting its movement and ability to surface. Such an incident occurred on 15 June 1988, as a juvenile green turtle became entangled in a net at night with a large adult loggerhead. Over the 13 year history of the canal capture program, only 10 of the more than 1,900 vitiess.

turtles entrapped in the canal have drowned as a result of netting acti-Most recent mortalities in the intake canal apparently resulted from drownings at the AlA barrier net and the newly constructed security intrusion barrier. A dramatic increase in loggerhead mortalities between 1985 and 1986 (Table 2) was thought to have been related to adjustments made to the A1A barrier net during the latter part of 1985 (ABI, 1987).

Presumably, these adjustments increased the probability of a turtle drowning. A new barrier net installed in November 1987 apparently corrected previous problems, as no mortalities were recorded at the A1A bridge during 1988.

During 1988, six loggerheads and two Kemp's ridleys breached the A1A barrier net and entered the western portion .of the intake canal where capture efforts are less effective. All but one of these turtles were found dead at the security intrusion barrier. The other turtle, a Kemp's ridley, was found floating in the canal between the intrusion barrier and the plant's intake wells. The condition of the turtles breaching the AlA barrier net is not known, but previous observations suggest that sick or injured turtles may be more susceptible to drowning at the intrusion 39

0 barrier than healthy turtles {ABI, 1988). The adult Kemp's ridley found at the intrusion barrier had one disfigured front flipper, the result of a previous injury or malformity at birth. Two of the loggerheads were very emaciated, suggesting that they too may have been in poor health at the time of entrapment.

In addition to the 8 mortalities recorded from the intake canal during 1988, another turtle removed from the canal in poor condition la)er died. . It was a small green turtle that was very emaciated and lethargic. It was transferred to the Florida Department of Natural Resources for rehabilitation, but succumbed to unknown ailments 10 days later.

Reca ture Incidents Since the St. Lucie Plant capture program began, most turtles removed alive from the intake canal have been tagged and released into the ocean at various locations along Hutchinson Island. Consequently, individual turtles loggerheads

. can be identified as long as they retain their tags.

Over the 13 year history of turtle entrapment at the St. Lucie Plant, 50 individuals (49 and 1 green) have been removed from the canal more than once. Several other turtles with tag scars have also been removed, indicating that the actual number of recaptures may be higher.

Of the 49 individual loggerheads known to have been caught more than once, 35 were caught twice, six were caught three times, four were caught four times, two were captured six times, one was caught seven times and 40

one was caught on eight separate occasions, yielding a total of 82 recap-ture incidents. Release site did not appear to have any effect on a turtle's probability of being recaptured. Turtles released both north and south of the plant returned. Recaptures also did not appear to be related to size, as both juveniles and adults were captured more than once (range of SLCL

= 47-89 cm). However, the majority of recapture incidents involved juveniles and sub-adults (SLCL <70cm).

Recapture intervals for loggerheads ranged from four to 858 days, with a mean of 148 days (+160.1 days). The only green turtle caught more than once was captured on two occasions, returning to the canal 59 days after first being released into the ocean. About 55 percent of all loggerhead recapture incidents occurred within 90 days of previous cap-ture and 91 percent within one year (Figure 22). The average interval between first and last capture was 251 days (+283.4 days). These data suggest that residency times of loggerheads within the nearshore habitat adjacent to the St. Lucie Plant are relatively short. Similar findi ngs have been reported for loggerheads inhabiting the Mosquito/Indian River Lagoons of east-central Florida (Mendonca and Ehrhart, 1982).

SUMMARY

A gradient of increasing loggerhead turtle nest densities from north to south along the northern half of Hutchinson Island has been shown during all survey years. This gradient may result from variations in beach topography, offshore depth contours, distribution of nearshore reefs, onshore artificial lighting and human activity on the beach at

S night. Low nesting activity in the vicinity of the power plant during 1975 and from 1981 through 1983 was I

attributed to construction of power plant intake and discharge systems. Nesting returned to normal or above normal levels following both periods of construction. Power plant opera-tion, exclusive of intake/di scharge construction, has had no significant effect on nest densities.

There have been considerable year-to-year fluctuations in loggerhead nesting activity on Hutchinson Island from 1971 through 1988.

Fluctuations are common at other rookeries and may result from overlapping of non-annual breeding populations. Despite these fluc-tuations, loggerhead nesting activity has remained relatively high during the last seven years. No relationship between total nesting and power plant operation or intake/discharge construction was indicated.

I Temporary declines in loggerhead nesting activity have been attri-buted to cool water intrusions that frequently occur over the continental shel f of southeast Florida. Though temporal nesting patterns of the Hutchinson Island population may be influenced by natural fluctuations in water temperature, no significant effects due to power plant operation 1

have been indicated.

Since nest" surveys began in 1971, raccoon predation was considered the major cause of turtle nest destruction on Hutchinson Island. From 1971 through 1977, overall predation rates in the nine survey areas were between 21 and 44 percent. However, a pronounced decrease in raccoon 42

Cl predation occurred after 1977, and overall predation rates in the nine survey areas have not exceeded ten percent since 1979. Decreased preda-tion by raccoons probably reflects a decline in the raccoon population.

During 1988, 74 green turtle and 33 leatherback turtle nests were-recorded on Hutchinson Island. Green turtle nesting activity exhibited considerable annual fluctuations, as has been recorded at other rookeries, but has remained relatively high during the last six years.

Leatherback turtle nest densities have remained low on Hutchinson Island; however, increased nesting during recent years may reflect an overall increase in the number of nesting females in the Hutchinson Island area.

During 1988, 134 loggerheads, 42 green turtles and 5 Kemp's ridleys 0

were removed from the St. Lucie Plant intake canal. Since monitoring began in May 1976, 1,631 loggerhead, 269 green, 8 leatherback, 6 hawks-bill and 15 Kemp's ridley turtles have been captured. Over the life of the monitoring program, annual catches for loggerhead turtles have ranged from 33 in 1976 (partial year of plant operation and monitoring) to a high of 195 in 1986. Yearly catches of green turtles have ranged from 0 in 1976 to 69 in 1984. Differences in the number of turtles entrapped during different years and months are attributed to natural variation in the occurrence of tu'rtles in the vicinity of the offshore intake struc-'ures, rather than to any influence of the plant itself.

Size-class di stributions of loggerhead turtles removed each year from the canal have consistently been predominated by juveniles and sub-43

adults between 50 and 70 cm in straight line carapace length. Most green turtles entrapped in the canal (about 80 percent) were juveniles 40 cm or less in length. For both species, the largest number of captures for all years combined occurred during the winter, but these seasonal peaks were much more pronounced for green turtles. Sex ratios of both adult and immature loggerheads caught in the canal continued to be biased towards females.

During 1988, about 87 percent of all loggerheads and green turtles removed fr om the canal were categorized by physical appearance as being in good to excellent condition. Over the entire 13 year monitoring period, 71 and 78 percent, respectively, of all loggerhead and green turtle captures have involved individuals in these categories; 21 percent 0

of the loggerheads and 13 percent of the green turtles removed from the canal have been in fair or poor condition.

About 13 percent of the turtles removed from the intake canal during 1988 had obvious injuries. However, it appeared that all but one of these injuries were sustained prior to entrapment. Once in the canal, turtles confined east of AlA usually had very brief residency times and thus the relative condition of most turtles was not affected by their entrapment. During 1988, 6 loggerheads, 23 green turtles and 4 Kemp's ridleys swam west of the AlA bridge. All of the loggerheads and two of the Kemp's ridleys were retrieved at- the security intrusion barrier. All of the gr een turtles and the remaining Kemp's ridleys were removed from the canal at the intake wells. Since monitoring began, about 9 percent

of al 1 loggerhead and 49 percent of al 1 green turtl e captures have occurred at the intake wells.

During 1988, two Kemp's ridley, two green and six loggerhead mor-talities were recorded for the intake canal. The majority of these deaths appeared to have resulted from drowning, although the exact causes of death could not be determined. The intrusion barrier was probably responsible for the loggerhead and ridley mortalities, while the greens died from entanglement in the turtle nets.

Since intake canal monitoring began in 1976, 7.5 percent of the loggerheads and 6.7 percent of the green turtles removed from the canal were dead. The four Kemp's ridley mortalities in 1987 and 1988 were the only deaths recorded for this'pecies since monitoring began; two of these animals appeared to be in poor health prior to their entrapment in the canal. A11 of the leatherbacks and hawksbills captured at the St.

Luci e Plant have been captured alive and released into the ocean.

45

LITERATURE CITED ABI (Applied Biology, Inc.") 1977. Ecological monitoring at the Florida Power & Light Co. St. Lucie Plant, annual report 1976. Volumes I and II. AB-44. Prepared by Applied Biology, Inc. for Florida Power

& Light Co., Miami.

1978. Ecological monitoring at the Florida ower L>g t o. t. Lucie Plant, annual report 1977. Volumes I and II. AB-101. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami.

1979. Florida Power & Light Company, St.

Luci e Plant annual non-radiological environmental monitoring report 1978. Volumes II and III, Biotic monitoring. AB-177. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami .

1980a. Florida Power & Light Company, St.

Luci e P ant annual non-radiological environmental monitoring report 1979. Volumes II and III, Biotic monitoring. AB-244. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami .

1980b. Turtle entrainment deterrent study.

AB-290. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami.

198la. Successful relocation of sea turtle nests near the St. Luci e Plant, Hutchinson Island, Florida. AB-317.

Prepared by Applied Biology, Inc. for Florida Power & Light Co.,

Mi ami.

1981b. Florida Power & Light Company, St.

Lucie P ant annual non-radiological environmental monitoring report 1980. Volumes II and III, Biotic monitoring. AB-324. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami.

1981c. Proposed St. Lucie Plant preopera-tiona and operational biological monitoring program -August 1981.

AB-358. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami.

1982. Florida Power & Light Company, St.

Lucie Plant annual non-radiological environmental monitoring report 1981. Volumes II and III, Biotic monitoring. AB-379. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami.

1983. Florida Power & Light Company, St.

Lucie Plant annual non-radiological aquatic monitoring report 1982.

Volumes I and I I. AB-442. Prepared by Applied Biology, Inc. for Florida Power & Light Co., Miami.

I LITERATURE CITED (continued)

ABI (Applied Biology', Inc.). 1984a. Florida Power 8 Light Company, St.

Lucie Plant annual non-radiological environmental monitoring report 1983. Volumes I and I I. AB-530. Prepared by Applied Biology, Inc.

for Florida Power 5 Light Co., Miami.

1984b. Florida Power 8 Light Company, St.

ucs e ant annua envi ronmental operating report 1983. AB-533.

Prepared by Applied Biology, Inc. for Florida Power 5 Light Co.,

Mi ami.

1985a. Florida Power 8 Light Company, St.

Lucie Plant annual non-radiological environmental monitoring report 1984. AB-553. Prepared by Applied Biology, Inc. for Florida Power 8 Light Co., Juno Beach.

1985b. Florida Power 8 Light Company, St.

Luci e P ant annua envi ronmental operating report 1984. AB-555.

Prepared by Applied Biology, Inc. for Florida Power 8 Light Co.,

Juno. Beach.

1986. Florida Power 8 Light Company, St.

ucs e P ant annua envs ronmental operating report 1985. AB-563.

Prepared by Applied Biology, Inc. for Florida Power 8 Light Co.,

Juno Beach.

1987. Florida Power 5 Light Company, St.

Lucie Plant annual envi ronmental operating report 1986. AB-579.

Prepared by Applied Biology, Inc. for Florida Power 8 Light Co.,

Juno Beach.

1988. Florida Power & Light Company, St.

Luci e Pl ant annua envs ronmental operating report 1987. AB-595.

Prepared by Applied Biology, Inc. for Florida Power 5 Light Co.,

Juno .Beach.

I Baldwin, W.P., Jr. and J.P. Lofton, Jr. 1959. The loggerhead turtles of Cape Romain, South Carolina. Previously unpublished manuscript abridged and annotated by D.K. Cal dwel 1, without the authors.

In D.K. Caldwell and A. Carr, coordinators, The Atlantic loggerhead sea turtle, Caretta caretta caretta (L.), in America. Bulletin of the Florida State Siuseum, B> ological Sciences, 4( 10):319-34B.

Bel lmund, S., M T. Masnik and G. LaRoche. 1982. Assessment of the impacts of the St. Lucie 2 Nuclear Station on threatened or endangered species. U.S. Nuclear Regulatory Commission, Office of Nuclear Reactor Regulation.

47

LITERATURE CITED (continued)

Bustard, H.R. 1968. Protection for a rookery: Bundaberg sea turtles.

Wildlife in Australia 5:43-44.

Bustard, H.R. and P. Greenham. 1968. Physical and chemical factors affecting hatching in the green sea turtle, Chelonia ~mdas (L.).

Ecology 49(2):269-276.

Caldwell, D.K. 1962. Comments on the nesting behavior of Atlantic loggerhead sea turtles, based primarily on tagging returns.

quarterly Journal of the Florida Academy of Sciences 25(4):

287-302.

Caldwell, D.K., A. Carr and L.H. Ogren. 1959. Nesting and migration of the Atlantic loggerhead turtle. In D.K. Caldwell and A. Carr, coor-dinators, The Atlantic loggerhead sea turtle Caretta caretta caretta (L.), in America. Bulletin of the Florida State Museum, BiologicaF Sci ences, 4(10):295-308.

Camp, D.K., N.W; Whiting and R.E. Martin. 1977. Nearshore marine eco-1 ogy at Hutchinson Isl and, Fl orida: 1971-1974. V. Arthropods.

Florida Marine Research Publications 25: 1-63.

Carr, A., A.

~ t1eyl an, J. Mortimer,

~ K.~ Bjorndal and T. Carr.~ 1982.~

Surveys of sea turtle populations and habi tats in the Western Atlantic. NOAA Technical Memorandum NMFS-SEFC-91:1-82. ~

Davis, G.E., and M.C. Whiting. 1977. Loggerhead sea turtle nesting in Everglades National Park, Florida, U.S.A. Herpetologica 33:18-28.

Di amond, A.W. 1976. Breeding biology and conservation of Hawksbi1 1 turtles, Eretmochel s imbricata L., on Cousin Island, Seychelles.

Biol ogi ca onserva ion RH5~

Ehrhart, L.M. 1979. Reproductive characteristics and management poten-tial of the sea turtle rookery at Canaveral National Seashore, Florida. Pages 397-399 in Linn, R.M., ed. Proceedings of the First Conf e rence on Sci ent i fs c Research in the Nat i onal Parks, 9-12 November, 1976, New Orleans, La. NPS Trans. and Proc. Ser. No. 5.

Ehrhart, L.M. 1980. Threatened and endangered species of the Kennedy Space Center: marine .turtle studies. In A continuation of baseline studies for environmentally monitoring space transportation systems (STS) at John F. Kennedy Space Center. Contract No. NAS-10-8986.

Vol. IV, NASA Report 163122. September 1980.

Ernest, R.G., R.E. Martin, B.D. Peery, D.G. Strom, J.R. Wilcox and N.W.

Wal ls. 1988. Sea turtl e entrapment at a coastal power pl ant.

Pages 270-301 in Mahadevan, K., R.K. Evans, P". Behrens, T. Biffar and L. Olsen, eds. Proceedings, Southeastern Workshop on Aquatic Ecological Effects of Power Generation. Report No. 124, Mote Marine Laboratory, Sarasota, Florida.

48

LITERATURE CITED (continued)

Fowler, L.E. 1979. Hatching success and nest predation in the green sea turtle, Chelonia ~mdas, at Tortuguero, Costa Rica. Ecology 60(5):945-955.

Futch, C.R. and S.E. Dwi nell. 1977. Nearshore marine ecology at Hutchinson Island, Florida: 1971-1974. IV. Lancelets and Fishes.

Florida Marine Research Publications 24: 1-23.

Gallagher, R.M. 1977. Nearshore marine ecology at Hutchinson Island, Florida: 1971-1974. II. Sediments. Florida Marine Research Publications 23: 6-24.

Gallagher, R.M. and M.L. Hollinger. 1977. Nearshore marine ecology at Hutchinson Isl and, Fl orida: 1971-1974. I. Introduction and rationale. Florida Marine Research Publications 23: 1-5.

Gal 1 agher, R.M., M.L. Ho 1 linger, R.M. Ing1 e and C.R. Futch. 1972.

Marine turtle nesting on Hutchinson Island, Florida in 1971.

Florida Department of Natural Resources, Special Scientific Report 37:1-11.

Hendrickson, J .R. and E. Balasingam. 1966. Nesting beach preferences of Malayan sea turtles. Bulletin of the National Museum Singapore 33(10):69-76.

Henwood, T.A. 1987. Movements and seasonal changes in loggerhead turtle, Caretta caretta, aggregations in the vicinity of Cape Canaveral, Florida~lgyg-84). Biological Conservation 40:191-202.

Hi 1 1 estad, H.O., J.I. Ri chardson, C. McVea, Jr. and J.M. Watson, Jr.

1982. Worldwide incidental capture of sea turtles. Pages. 489-496 in Bjorndal, K.A., ed. Biology and conservation of sea turtles.

Wmithsonian Institution Press, Washington, D.C.

Hirth, H.F. 1980. Some aspects of the nesting behavior and reproductive biology of sea turtles. American Zoologist 20:507-523.

Hopkins, S.R., T.M. Murphy, Jr., K.B. Stansell and P.M. Wilkinson. 1979.

Biotic and abiotic factors affecting nest mortality in the Atlantic 1 oggerhead turtl e. Proceedings Annual

• Conference of South'eastern Fish and Wildlife Agencies 32:213-223.

Hughes, G.R. 1974. The sea turtles of southeast Africa, 1. Status, morphology and distributions. South African Association for Marine Bi ol ogi cal Research, Oceanographic Research Institute, Investigational Report No. 35:1-144.

LITERATURE CITED (continued)

~gh Zoologica d <<I 1976.

Africana 11(2~285-291.

<<( ((Cgg Irregular reproductive cycles in the Tongaland dg:CI Martin, R.E., R.G. Ernest, N.W. Wal 1 s and J.R. Wi1 cox. 1987. Size distribution and seasonal abundance of loggerhead and green turtles in nearshore waters off Hutchinson Island, Florida. Poster presented at Second Western Atlantic Turtle Symposium. Mayaguez, Puerto Rico, l,2-16 October 1987.

Mendonca, M.T. and L.M. Ehrhart. 1982.'ctivity, population size and structure of the immature Chelonia ~m das and Caretta caretta in Mosquito Lagoon, Florida. Copeia 1982: 161-167.

Moffler, M.D. and J.F. Van Breedveld. 1979. Nearshore marine ecology at Hutchinson Island, Florida: 1971-1974. X. Benthic al gae species list. Florida Marine Research Publications 34: 118-122.

Mortimer, J.A. 1982. Factors influencing beach selection by nesting sea turtles. Pages 45-51 in Bjorndal, K.A., ed. Biology and conserva-tion of sea turtles. Smithsonian Institution Press. Washington, D.C.

~ ~

NMFS (Na tional Marine Fisheries Service). 1978.,Final EIS listing and protecting the green sea turtle (Chelonia ~mdas), loggerhead sea

(~Li National D.C.

h>>g~

turtle (Caretta caretta) and tlie Pac>f>c R>dley sea turtle Marine Fisheries h

Service, 1 g gg Dept. of Commerce, I 1 1 1911.

Washington, NRC (U.S. Nuclear Regulatory Commission). 1982. Final environmental statement related to the operation of St. Lucie Plant Unit 2.

Docket No. 50-389.

O'ara, J. 1980. Thermal influences on the swimming speed of loggerhead turtle hatchli ngs. Copeia 1980(4):773-780.

Owens, D.W., J.R. Hendrickson, V. Lance and I.P. Callard. 1978. A technique for determining sex of immature Chelonia ~m das using a radi oimmunoassay. Herpetol ogi ca 34:270-273.

Owens, D.W. and G.J. Ruiz. 1980. New methods of obtaining blood and cerebrospinal fluid from marine turtles. Herpetologica 36:17-20.

Pritchard, P.C., P.R. Bacon, F.H. Berry, A.F. Carr, J. Fletemeyer, R.M.

Gallagher, S.R. Hopkins, R.R. Lankford, R. Marques M., L.H. Ogren, W.G. Pringle, Jr., H.A. Reichart and R. Witham. 1983. Manual of sea turtle research and conservation techniques. Prepared for the Western Atlantic Turtle Symposium, San Jose, Costa Rica, July 1983.

126 pp..

50

LITERATURE CITED (continued)

Prof fitt, C.E., R.E. Martin, R.G. Ernest, B.J. Graunke, S.E. LeCr oy, K.A. Muldoon, B.D. Peery, J.R. Wilcox and N. Williams-Walls. 1986.

Effects of power plant construction and operation on the nesting of the loggerhead sea turtle (Caretta caretta):1971-1984. Copeia 1986(3): 813-816.

Raymond, P.W. 1984. The effects of beach restoration on marine turtles nesting in south Brevard County, Florida. M.S. thesis, University of Central Florida.

Routa, R.A. 1968. Sea turtle nest survey of Hutchinson Island, Florida.

quarterly Journal Florida Academy of Sciences 30(4):287-294.

Schulz, J.P. 1975. Sea turtles nesting in Surinam. Zoologische Verhandeli ngen, uitgegeven door het Rijksmuseum van Natuurlijke Historic te Leiden, No. 143:1-144.

Smith, N.P. 1982. Upwelling in Atlantic shelf waters of south Florida.

Florida Scientist 45(2):125-138.

Sokal, R.R. and F .J . Rohlf. 1981. Biometry. The principles and prac-tice of statistics in biological research. W.H.- Freeman and Company, San Francisco. 859 pp.

Stancyk, S.E. 1982. Non-human predators of sea turtles and their con-trol. Pages 139-152 in Bjorndal, K.A., ed. Biology and conserva-tion of sea turtles. Smithsonian Institution Press. Washington, D.C.

Talbert, O.R., S.E. Stancyk, J .M. Dean and J .M. Will. 1980. Nesting activity of the loggerhead turtle (Caretta caretta) in South Carolina. I: A rookery in transition. ~opera 1999:709-718.

Taylor, C.B., and H.B. Stewart. 1958. Summer upwelling along the east coast of Florida. Journal of Geophysical Research 64(l):33-40.

Tester, L.A. and K.A. Steidinger. 1979. Nearshore marine ecology at Hutchinson I sl and; Fl orida: 1971-1974. VI I. Phytopl ankton, 1971-1973. Flor ida Marine Research Publications 34: 16-61.

Walker, L.M. 1979. Nearshore marine ecology at Hutchinson Island, Florida: 1971-1974. IX. Oiel plankton, 1973-1974. Florida Marine Research Publications 34: 99-117.

Walker, L.M., B.M. Gl ass and B.S. Roberts. 1979. Nearshore marine ecology at Hutchinson Isl and, Fl orida: 1971-1974. VI I I.

Zooplankton, 1971-1973. Florida Marine Research Publications 34:

62-98.

51

I LITERATURE CITED (continued)

Walker, L.M. and K.A. Steidinger. 1979. Nearshore marine ecology at Hutchinson Isl and, Fl orida: 1971-1974. VI. Plankton dynami cs, 1971-1973. Florida Marine Research Publications 34: 1-15.

Wibbels, T., D. Owens, Y. Morris and M. Amoss. 1984. Sex ratios of loggerhead sea turtles captured along the Atlantic coast 'mmature of the United States. Final Report to the National Marine Fisheries Service. Contract No. NA81-GA-C-0039. 47 pp.

Williams-Walls, N., J . O'ara, R.M. Gallagher, D.F. Worth, B.D. Peery and J.R. Wilcox. 1983. Spatial and temporal trends of sea turtle nesting on Hutchinson Isl and, Fl orida, 1971-1979. Bul 1etin of Marine Science 33(1):55-66.

Witherington, B.E. and L.M. Ehrhart. 1987. Status and reproductive characteristics of green turtles (Chelonia ~mdas) nesting in Florida. Poster presented at Second Western Atlantic Turtle Symposium. Mayaguez, Puerto Rico, 12-16 October 1987.

Worth, D.F. and M.L. Hol linger. 1977. Nearshore marine ecology at Hutchinson Island, Florida: 1971-1974. III. Physical and chemical environment. Florida Marine Research Publications 23: 25-85.

Worth, D.F., and J.B. Smith. 1976. Marine turtle nesting on Hutchinson Island, Florida, in 1973. Florida Marine Research Publications 18:

1-17.

52

GULF. OF MEXICO 0

0 YARDS IDLDMEMRS 2000 I 000 0 ~ ~

SCALE 0

St. Lucle Plant Figure 1. Location of the St. Lucie Plant.

gt g ~ 'L 8

~o

~o

~ .4

'~ oe T ~+~@~

Vg HUTCH I NSON ISLAND 7 ~ "L

~ g pp

.C, \ ~

~pe~)' DISCHARGE G+ .: PIPES

~@X~

0 0 INTAKE'

~@X~

INTAKE HEADWALL',

WELLS INTAKE STRUCTURES

'INTRUSION BARRIER BARRIER INTAKE 500 CANAL 0 250 METERS Figure 2. St. Lucie Plant cooling water intake and discharge system.

Cl Ft Pierce InIet A

4 a

1 E 4

I State p/1 Hwy AlA H 2 Q0 0 3

b a

il,t 0

4 0 FPL ST. LUCIE PLANT Q

a R

5 a

S a4 U.S. Hwy I

4 w/6 z/7 BB CC DD EE 8

pg+R '

FF GG

~ a e a a a>a HH 9

0 3 km

~ St. Lucle Inlet Figure 3. Designation and location of nine 1.25-km segments and thirty-six 1-km segments surveyed for sea turtle nesting. Hutchinson Island, 1971-1988.

y 350 300 250 (0

Z 0 200 Q

Z 150 100 50 1 2 3 4 5 6 7 8 9 NORTH POWER PLANT SOUTH Figure 4. Mean annual number of loggerhead turtle nests in each of the nine1.25-km-long survey areas, Hutchinson Island, 1971-1987, compared with number of nests during 1988. Horizontal lines are means, boxes enclose plus or minus one standard deviation, vertical lines are ranges, and closed circles are 1988 values (1980 data were excluded because not all areas were surveyed).

1 300 250 200 Z

150 D

Z 100 50 ABCDEFGH I JKLMNOPQRSTUVWXYZABCDEFGH ABCDEFGH I J I J NORTH 0 POWER PLANT SOUTH Figure 5. Mean annual number of loggerhead turtle nests in each of the thirty-six 1-km-long survey areas, Hutchinson Island, 1981-1987, compared with number of nests during 1988. Horizontal lines are means, boxes enclose plus or minus one standard deviation, vertical lines are ranges, and closed circles are 1988 values.

500 g) 400 O

Z 300 D

200 100 ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGH ABCDEFGH I J I J NORTH POWER PLANT SOUTH

- Figure 6. Mean annual number of loggerhead turtle emergences in each of the thirty-six 1-km-long survey areas, Hutchinson Island, 1981-1987, compared with the number of emergences during 1988. Horizontal lines are means, boxes enclose plus or minus one standard deviation, vertical lines are ranges, and closed circles are 1988 values.

100 80

<o M ~ ~

M UJ O

O M 60 G

Z I-M UJ Z

40 20 ABC DEFG H I J K LMNOPQ RS TU VWX Y ZA B CDE FGH I J A B CDE FGH I J NORTH 0 POWER PLANT SOUTH Figure 7. Mean annual loggerhead turtle nesting success (percentage of emergences that resulted in nests) for each of the thirty-six 1-km-long survey areas, Hutchinson Island, 1981-1987, compared with nesting success during 1988. Horizontal lines are means, boxes enclose plus or minus one standard deviation, vertical lines are ranges, and closed circles are 1988 values.

250 o o Area 4 ( Power Plant Site )

e ~ Area 5 (Control Site) 200 (0 a /

z /

O 150 /

/

/

/ /

/

z /

/

100 50 71 73 75 77 79 80 81 82 83 84 85 86 87 88 Figure 8. Number of loggerhead turtle nests in areas 4 and 5, Hutchinson Island, 197W988. Arrows denote years during which intake/discharge construction occurred in area 4.

5000 V) 4000 z

0 3000 CC Kl 2000 z

1000 M 10000 O

8000 6000 4000 D

z 2000 g 80 (0

M lU O 60 O

D CO (9 40 z

I-CO UJ z 20 1981 1982 1983 1984 1985 1986 1987 1988 Figure 9. Annual number of nests, number of emergences and nesting success along the entire 36.0-km-long Atlantic coastline of Hutchinson Island, 1981-1988.

30 O

0 28 K

26 24 I-22 20 90 Z

O 60 D

Z 30 0

15 30 5 15 30 5 15 30 5 15 30 5 15 30 5 15 APR MAY JUN JUL AUG SEP Figure 10. Daily loggerhead turtle nesting activity and water temperature, Hutchinson Island, 1988.

ALL AREAS 50 AREA 1 50 AREA 2 50 AREA 3 o 50 0

AREA 4 CI (0 50 Z

AREA 5 50 AREA 6 50 AREA 7 50 AREA 8 50 AREA 9 50 1971 1973 1975 1977 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 Figure 11. Percentage of loggerhead turtle nests destroyed by raccoons in the nine 1.25-km-long survey areas, Hutchinson Island, 1971-1988.

i 50 Destroyed by ghost crabs Lrrl Destroyed by raccoons and ghost crabs Qgy. Destroyed by raccoons g 40 0

CI M

g 30 z

ot 0

K W

z 20 I 12% 15%

12%::

10 II

(% 6% 5%

I It I

1%

1%

y Or A BCD EF GH I JKLMNOPQRSTUVWXYZABCDEFGH I J ABCDEFGH I J NORTH 0 POWER PLANT SOUTH Figure 12. Number of loggerhead turtle nests destroyed by raccoons and ghost crabs and percentage of nests destroyed in each 1-km-long survey area, Hutchinson Island, 1988.

i

--p 8

p 0

Green (Chelonia mydas)

Leatherback (Dermochelys cori acea)

/

/

Q

~8 Ii Pg I

60 I /

I I I I

/

/ I h 45 / ~l I

I r ~R, I

I 30 I I

I pW I 15 I I

1971 1973 1975 1977 1979 1981 1982 1983 1984 1985 1986 1987 1988 Figure 13. Annual numbers of green turtle and leatherback turtle nests, Hutchinson Island, 197W988.

200

~ LOGGERHEAD (Caret ta caretta) 0- M GREEN (Chelcnia m~daa) 80 175 0 70 I)

/ $

150

/ 60 5 0 \ Q I O 125 50 z

/

100

/ ~O 40

/ 0

/ 0 75 0 \ 30

/ mm

/ I D Z

50

/

/ /0 o 20

/

/ r 0 25 0 X/ 10 a---<- 0r 0

1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 Figure 14. Number of loggerhead and green turtles removed each year from the intake canal, St. Lucie Plant, 1976-1988.

50 50 40 40 (0

I-O 30 30 D

z z 20 20 10 10 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC MONTH OF CAPTURE Figure 15. Mean number of loggerheads captured each month, St. Lucie Plant intake canal, 1977-1987, compared with number of monthly captures during 1988. Horizontal lines are means, boxes enclose plus or minus one standard deviation, vertical lines are ranges, and closed circles are 1988 values.

350 300 300 250 250 (0

D 0

O z 200 200 0

K Q3 D

z 150 150 100 100 50 50

<<40 41-45 46-50 51-55 56-60 61-65 66-70 71-75 76-80 81-85 86-90 91-95 96- 101- 106- >110 STRAIGHT LINE CARAPACE LENGTH (cm) 100 105 110 Figure 16. Length distribution (SLCL) of loggerhead sea turtles (N=1,482) removed for the first time from the intake canal, St. Lucie Plant, 1976-1988. No data

. collected for 67 individuals.

300 300 250 250

)

CI CI z

200 200 0

K m

D z

150 150 100 100 50 50

<10 11-20 21-30.31-40 41-50 51-60 61-70 71-80 81-90 91-100 101- 111- 121- 131- 141- ~150 WFlGHT (kg) 110 120 130 140 150 Figure 17. Weight distribution of live loggerhead sea turtles (N=1,289) removed for the first time from the intake canal, St. Lucie Plant, 1976-1988.

No data collected for 260 individuals.

V 100 100 80 80 (0

D

)O0 60 60 U

0 K

ILJ 03 40 40 20 20

~15 16- 21- 26- 31- 36- 41- 46 56 66 76 86- 91- 96- 101- 106- ) 110 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 STRAIGHT LINE CARAPACE LENGTH (crn)

Figure 18. Length distribution (SLCL) of green turtles (N=261) removed for the first time from the intake canal, St. Lucie Plant, 1976-1988. No data collected for 7 individuals.

175 150 150

~ 125 125 D

0 0

Z

~ 100 100 0

K Q3 D

Z 75 75 50 50 25 25 1-5 6-10 11-15 16-20 21-25 26-30 31-35 36-40 41-45 46-50 51-100 101-150 151-200 )200 WEIGHT (kg)

Figure 19. Weight distribution of green turtles (¹255) removed for the first time from the intake canal, St. Lucie Plant, 1976-1988. No data collected for 13 individuals.

MALES 50 50 40 40 D

O

)a 30 30 0

K D

20 20 10 10 I JAN FEB MAR APR MAY JUN JUL AUG SEP OCT I NOV DEC MONTH OF CAPTURE Figure 20. Numbers of adult loggerheads (N=244), including recaptures, removed eachmonth from the intake canal, St. Lucie Plant, 1976-1988.

~ ~ CANAL CAPTURES 500 0- -0 NESTS 40 0 400

/

/ z

/ (0 I-

/

/

30 / 300

/

0 z

20 200

/ zz 10 100 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 Figure 2l. Comparison of captures of adult female loggerheads in the intake canal, St. Lucie Plant, 1976-1988, and numbers of loggerhead emergences in area 4 adjacent to the plant. Nesting activity was not monitored in 1976 and 1978.

I 100 100 OA 0

//

P P'

80 0

/ 80 0

G /

I

/9 0

I

/

/

60 I0 60

/0 I- /

9 I

I I

D 9 l

O 40 40 I

I I

I I

9 I

I 20 I Interval between successive captures I

20 I

I Interval between first and last capture 200 400 600 800 1000 1200 1400 RECAPTURE INTERVAL(days)

Figure 22. Cumulative percentage of all loggerhead recaptures occurring within various time intervals between successive captures (N=80) and first and last capture (N=47), St. Lucie Plant intake canal 1976-1988.

TABLE 1 ESTIMATES OF THE NUMBERS OF LOGGERHEAD TURTLE NESTS ON HUTCHINSON ISLAND BASED ON SURVEYS OF NINE 1.25-KM-LONG SURVEY AREAS, 1971-1988, COMPARED TO THE ACTUAL NUMBER OF NESTS ON THE ISLAND, 1981-1988 Year 1971 1973 1975 1977 1979 1981 1982 1983 1984 1985 1986 1987 1988 v Number of nests in the nine 1420 1260 1493 932 1449 1031 1634 1592 1439 1623 1839 1645 1701 1.25-km-long survey areas Extrapolation from the nine 4175 3704 4389 2740 4260 3031 4804 4680 4231 4772 5407 4836 5001 survey areas to the entire island (see text)

Actual number of nests on 3115 4690 4743 4277 4877 5483 4623 4990 the entire island

I TABL TOTAL NUHBER OF SEA TURTLE CAPTURES AND (NUHBER OF DEAD)

TURTLES REHOYED FROH THE INTAKE CANAL ST. LUCIE PLANT 1976 - 1988 S ecies Year lo erhead reen leatherback hawksbi ll Kem s ridle Total 1976 33(4) 33(4) 1977 so(5) 5(2) S6(7) 1978 138(19) 6(1) 148(20) 1979 173(13) 3(1) 176(14) 1980 116(5) 1O(3) 126(8) 1981 62(5) 32(2) 97(7) 1982 101(16) 110(16) 1983 119(4) 23(4) 142(8) 1984 148(3) 69(2) 22O(5) 1985 157(4) 14 172(4) 1986 195(27) 22(1) 220(28) 1987 175(11) 35 6(2) 218(13) 1988 134(6) 42(2) 5(2) 181(10)

Total 1631(122) 269(18) s(o) 6(o) 15(4) 1929(144)

Annual Heana 133.2 22.4 0.7 0.5 1.3 158.0 Excludes 1976 (partial year of plant operation).

TABLE 3 TOTAL NUMBER AND (NUMBER OF DEAD) LOGGERHEAD TURTLES REMOVED EACH MONTH FROM THE INTAKE CANAL ST. LUCIE PLANT 1976 - 1988 Month 1976 1977 1978 1979 1980 1981 1982 1983 January 13 19 24(3) 16 11(1) 6(2) 39 February 8(1) 11(2) 29(1) 21(2) 11(3) 11 13(1)

March 7 27(2) 11 14 6 14 April 5(2) 19(5) 17 10 14 May 2 1 3(1) 0 7 6 17(4)

June 0 5 10 3(1) 8(3) 6 7 7(1)

July 7(1) 4 0 27(2) 0 1 7 August 2 3 12 17(2) 12 6 2(1)

September 1 15(1) 1 8(1) 19 2(1) 9(1) 8(2)

October 7 9(1) 17(2) 15(3) 7 0 9(5) 17 November 5(3) 5 15(7) 12 4 0 4(2) 5 December 9 5 4 10 8 3 1(1) 12 Total 33(4) 80(5) 138(19) 173(13) 116(5) 62(5) 101(16) 119(4)

0 (continued)

TOTAL NUMBER AND (NUMBER OF DEAD) LOGGERHEAD TURTLES REMOVED EACH MONTH FROM THE INTAKE CANAL ST. LUCIE PLANT 1976 - 1988 Monthly Percent of Month 1984 1985 1986 1987 1988 Total Mean Total Catcha January 13 11 15(2) 26(3) 7 200(11) 16.7 12.5 February 15 16(4) ll 10(3) 167(17) 13.9 10.5 March 20 14(4) 8(1) 11 139(7) 11.6 8.7 April 2(1) 13 20(2) 24(3) 13(2) 137(15) 11.4 8.6 May 16 12 23(1) 28 126(6) 9.7 7.8 June 28(1) 17 20(1) 26(1) 30 167(8) 12.8 10.5 July 12(1) 20(3) 26(2) 19(1) 5 135(10) 10.4 8.0 August 26 19(1) 34(6) 17(1) 159(11) 12.2 9.8 September 16 14 9(4) 4 11(1) 117(11) 9.0 7.3 October 10 7 11(2) 3 114(13) 8.8 6.7 November 3 8 5 80(12) 6.2 4.7 December 2 10 9 9 90(1) 6.9 5.1 Total 148(3) 157(4) 195(27) 175(11) 134(6) 1631(122)

Excludes 1976 (partial year of plant operation).

TABLE 4 TOTAL NUMBER AND (NUMBER OF DEAD) GREEN TURTLES REMOVED EACH MONTH FROM THE INTAKE CANAL ST. LUCIE PLANT 1976 - 1988 Month 1976 1977 1978 1979 1980 1981 1982 1983 January 2 1 0 0 20(1) 8(1)

February 2(1) 2 1 5(1) 7 March 0 2 0 4(1) 1 3(2)

April 0 1(1) 0 May 1(1) 0 0 June 0 1 1(1) 0 July August 2(1)

September October November 4(1)

December Total 5(2) 6(1) 3(1) 10(3) 32(2) 23(4)

TABLE 4 (continued)

TOTAL NUMBER AND (NUMBER OF DEAD) GREEN TURTLES REMOVED EACH MONTH FROM THE INTAKE CANAL ST. LUCIE PLANT 1976 - 1988 Monthly Percent of Month 1984 1985 1986 1987 1988 Total Mean Total Catch January 37(1) 4 1 4 12 90(3) 7.5 33.5 February 10 1 1 1 ll 45(2) 3.7 16.7 March 0 1 6(1) 3 4 24(4) 2.0 8.9 April 1 2 15(2) 1.3 5.6 Hay 0 0 7(1) 0.5 2.6 June 3 0 6(2) is(3) 1.2 5.9 July 2 0.6 3.0 August 2 1 9(i) 0.7 3.3 September 1 0 0.4 1.9 October 6 1 0.8 4.1 November 4(1) 1 18(2) 1.4 6.7 December 3 1. 21 1.6 7.8 Total 69(2) 14 22(1) 35 42(2) 269(18)

NUMBER OF MONTHLY CAPTURES BY SIZE CLASS FOR LOGGERHEAD TURTLES REMOVED FROM THE INTAKE CANAL ST. LUCIE PLANT 1977 1988a Size classes SLCL in cm b Juveniles/Sub-Adults Transition Adults Month 41-50 51-60 61-70 Total Percenta e 71-80 Percenta e 81-90 91-100 >100 Total Percenta e January 76 69 159 14.3 23 . 12.4 10 2 0 12 5.0 February 67 54 132 11.9 17 9.2 1 1 8 3.3 March 57 47 ill 10.0 16 8.6 4 0 6 2.5 April 12 41 47 100 9.0 19 10.3 1 0 7 2.9 May 30 7.6 5.9 14 12 0 26 10.7 June 46 40 93 8.4 13 7.0 34 17 2 53 21.9 July 40 31 6.7 10 5.4 21 19 3 43 17.8 August 41 95 8.6 19 10.3 26 13 1 40 16.5 September 44 36 83 7.5 12 6.5 9 2 18 7.4 October 34 29 70 6.3 18 9.7 13 1 1 15 6.2 November 19 23 4.1 18 9.7 3 1 3.3 December 32 26 62 5.6 4.9 3 0 2.5 Total 86 542 480 1108 72.2 185 12.0 146 85 11 242 15.8 aExcluding 1976 (partial year of data) bNo data were collected for 63 individuals.

TA RELATIVE CONDITION OF SEA TURTLES REMOVED FROM THE INTAKE CANAL ST. LUCIE PLANT 1976 - 1988 Relative Lo erheads Greens Leatherbacks Kem 's ridle s Hawksbills All s ecies condition umber um er um er um er um er 301 18.5 89 33.1 1 12.5 2 13.3 4 66.6 397 20.6 393 24.1 46 17.1 2 13.3 1 16.6 - 442 22.9 467 28.6 75 27.9 6 75.0 3 20.0 1 16.6 552 28.6 261 16.0 28 10.4 1 12.5 3 20.0 293 15.2 77 4.7 7 2.6 1 6.7 85 4.4 122 7.5 18 6.7 4 26.7 144 7-5 10 0.6 6 2.2 16 0.8 TOTAL 1631 269 15 1929 1 Excellent - normal or above normal weight, active, very few or no barnacles or leeches, no wounds.

2 Very good intermediate good to excellent.

3 Good - normal weight, active, light to medium coverage of barnacles and/or leeches, wounds absent, healed or do not appear to debilitate the animal.

4 Fair intermediate poor. to good.

5 Poor - emaciated, slow or inactive, heavy barnacle coverage and/or leech infestation, debilitating wounds or missing appendages.

6 Dead 7 Alive but condition otherwise unknown.

4*)

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