466 



Abstract— All five species of sea tur- 

 tles in continental U.S. waters are 

 protected under the Endangered Spe- 

 cies Act of 1973 and the population 

 sizes of all species remain well below 

 historic levels. Shrimp trawling was 

 determined to be the largest source 

 of anthropogenic mortality of many of 

 the species. As a mechanism to reduce 

 the incidental catch of turtles in trawl 

 nets, turtle excluder devices have been 

 required intermittently in the shrimp 

 fishery since 1987. and at all times since 

 1994. The expanded turtle excluder 

 device (TED) regulations, implemented 

 in 1994, were expected to reduce 

 shrimp trawl capture of sea turtles 

 by 97%. Recent evidence has indicated 

 that the sizes of turtles stranding were 

 not representative of the animals sub- 

 jected to being captured by the shrimp 

 trawlers. The purpose of our study 

 was to compare the sizes of stranded 

 sea turtles with the size of the TED 

 openings. We compared the sizes of 

 stranded loggerhead tCaretta carctta), 

 green iChelonta mydas), and Kemps 

 ridley (Lepidochelys kempii ) sea turtles, 

 the three species most commonly found 

 stranded, to the minimum widths and 

 heights of TED openings. We found that 

 annually a large proportion of stranded 

 loggerhead turtles (33^7%) and a 

 small proportion of stranded green tur- 

 tles ( 1-7% ) are too large to fit through 

 the required minimum-size TED open- 

 ings. The continued high mortality of 

 sea turtles caused by bottom trawling 

 is reason for concern, especially for the 

 northern subpopulation of loggerhead 

 turtles, which cun-ently is not projected 

 to achieve the federal recovery goal of 

 reaching and maintaining prelisting 

 levels of nesting. 



Turtle excluder devices- 

 Are the escape openings large enough?* 



Sheryan P. Epperly 



Wendy G. Teas 



Southeast Fisheries Science Center 



National Marine Fishenes Service 



75 Virginia Beach Drive 



Miami, Florida 33149 



E-mail address (for S P Epperly): sheryan, epperlyrainoaa gov 



Manuscript accepted 12 February 2002. 

 Fish. Bull. 100:466-474 (2002). 



All five species of sea turtles in continen- 

 tal U.S. waters are protected under the 

 Endangered Species Act of 1973 (ESA, 

 PL93-205). Elasticity models of turtle 

 populations have indicated that the life 

 stages with the highest elasticity are 

 juveniles (i.e. a reduction in mortality in 

 these stages would result in the great- 

 est annual population multiplication 

 rate) (Crouse et al., 1987; Crowder et al., 

 1994; Heppell, 1998a, 1998b; Epperly et 

 al., 2001; Heppell et al., in press). Size 

 data indicate that the sea turtles most 

 often found dead on ocean beaches are 

 immature (Crouse et al., 1987; STSSNM 

 and shrimp trawling is thought to 

 account for the majority of these deaths 

 (Magnuson et al.. 1990; Caillouet et 

 al, 1991, 1996; Crowder et al., 1995). 

 Strandings, however, likely represent 

 only a small proportion of the animals 

 that die offshore (TEWG, 1998). 



Beginning in the fall of 1987, the 

 National Marine Fisheries Service 

 (NMFS) seasonally required turtle 

 excluder devices (TEDs) in shrimp 

 trawl nets on most vessels operating in 

 ocean waters off the southeastern U.S. 

 as a mechanism to reduce the inciden- 

 tal catch of turtles in general and the 

 catch of the large immature turtles in 

 particular (Federal Register, 1987); ves- 

 sels operating off Cape Canaveral and 

 off southwest Florida were required 

 to use TEDs all year. Boats working 

 in inshore waters were allowed to use 

 tow time limits in lieu of TEDs. The dif- 

 ference between offshore and inshore 

 regulations was due, in part, to the 

 lack of information on the distribution 

 and abundance of sea turtles in inshore 

 waters and to the lack of documenta- 

 tion of incidental captures by shrimp 

 trawlers working in these inshore wa- 



ters (Federal Register 1992a). For the 

 first few years implementation of the 

 regulations was delayed by challenges 

 in the courts and in Congress. The 

 regulations were implemented fully in 

 Spring 1990. 



Evidence of the importance of in- 

 shore areas to sea turtles, along with 

 evidence that shrimp trawlers catch 

 sea turtles in inshore waters (Epperly 

 et al., 199.5; NMFS- ) provided sufficient 

 justification for NMFS to expand re- 

 quirements for turtle excluder devices 

 in the shrimp fishery to all areas at all 

 times, including inshore waters; full 

 implementation of these requirements 

 was achieved by December 1994 (Fed- 

 eral Register, 1992a, 1992c). The ex- 

 panded TED regulations were expected 

 to reduce shrimp trawling capture of 

 sea turtles by 97% (Henwood et al., 

 1992). Since 1992, TEDs also have been 

 required in the winter trawl fishery 

 for summer flounder operating as far 

 north as Cape Charles, Virginia (Fed- 

 eral Register, 1992b). 



* Contribution PRD-99/00-07 of the South- 

 east Fisheries Science Center. Miami, 

 Florida 33149. 



' STSSN (Sea Turtle Stranding and Salvage 

 Network). 1998. Unpubl. data. The 

 Sea Turtle Stranding and Salvage Net- 

 work is a cooperative endeavor between 

 NMFS, other federal agencies, the states, 

 many academic and private entities, 

 and innumerable volunteers. Data are 

 archived at the National Marine Fisher- 

 ies Service Southeast Fisheries Science 

 Center, 75 Virginia Beach Dr, Miami. FL 

 33149. 



- NMFS (National Marine Fisheries Service). 

 1990. Unpubl. data. NMFS Galveston 

 Laboratorv, 4700 Avenue U, Galveston, 

 TX 77.551." 



