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Between 12th of April and 15th of June 1998, 13 confirmed Kemp's ridley turtle (Lepidochelys kempii) nests were found on the coast of southern Texas, USA. They represented: (1) the only confirmed Kemp's ridley nests found in the USA so far this year; (2) the greatest number of Kemp's ridley nests documented in Texas or in the USA during any single year; and (3) an increase in the number of Kemp's ridley nests detected in Texas for the fourth consecutive year (Shaver 1990, 1994a, 1995a, 1996a, 1997, in press a). Of the 13 nests, nine were found on North Padre Island at Padre Island National Seashore (PAIS), two on Mustang Island, and two on South Padre Island. During the last 50 years, more confirmed Kemp's ridley nests have been located at PAIS in south Texas than at any other location in the USA (Shaver in press a).

During the period 1978-1988, a joint Mexico-USA experimental project was conducted to determine the feasibility of increasing the levels of nesting of this endangered species at PAIS to provide an additional safeguard against extinction (Shaver 1990; US Fish and Wildlife Service and National Marine Fisheries Service 1992). Turtles in the project were hatched from eggs collected at the primary nesting beach at Rancho Nuevo, Tamaulipas, Mexico and incubated at PAIS. Steps were taken to experimentally imprint hatchlings to the beach at PAIS following which they were head-started at the National Marine Fisheries Service Laboratory in Galveston, Texas. The turtles were tagged and released (within their first year of life) into the Gulf of Mexico or adjacent bays (Caillouet et al. 1995, 1997). In 1998, there were four confirmed nests in south Texas by three Kemp's ridleys from this project (Table 1). Included were: (1) a 14 year old from the 1984 year-class found to have nested twice this year; (2) a 12 year old from the 1986 year-class found nesting once; and (3) an 11 year old from the 1987 year-class found nesting once. These three nesting females were identified from living tags, magnetic tags, and flipper tag scars. However, without the presence of a metal flipper tag it could not be determined whether the nesting female from the 1987 year-class had been imprinted at PAIS (n=1110) or Cayman Turtle Farm (n=130) (see Caillouet et al. 1995).

The first documented nesting in the wild of Kemp's ridleys from this project occurred at PAIS in 1996, and included: (1) a 13 year old from the 1983 year-class; and (2) a 10 year old from the 1986 year-class (Shaver 1996a, 1996b). Eggs laid by the turtles in this project, and virtually all other Kemp's ridley eggs detected on the south Texas coast from 1980-1998, were collected and incubated in a hatchery at PAIS, and most emerging hatchlings were released at PAIS (Shaver 1990, 1997). The nesting by turtles released as part of this project and production of hatchlings from their nests support the primary working hypothesis of the bi-national project; viz. that experimentally imprinted and head-started Kemp's ridleys are able to join the natural, wild population, find their way to nesting beaches, copulate successfully, and produce viable offspring (Eckert et al. 1994; Caillouet 1998). Furthermore, these clutches have been laid at or in proximity to the beach to which the turtles were imprinted as hatchlings, and were comparable in size to those at Rancho Nuevo.

The nine other Kemp's ridley nests on the south Texas coast during 1998 could not be conclusively linked to the experimental imprinting and head-starting project. Two Kemp's ridleys were observed by beach visitors but not examined by trained biologists. Four nests were detected only from tracks left in the sand by the nesting females (hatchlings confirmed the species). Two of the nesting turtles examined by the author (DS) had no tags or tag scars and one nesting turtle examined contained a PIT tag implanted when she nested near Rancho Nuevo in 1996. This is the first confirmed nesting in the USA by a Kemp's ridley turtle that had previously nested in Mexico. An individual that had been tagged while nesting at Rancho Nuevo in May 1997, was observed crawling on the beach at PAIS about one month later, but no nest was located during this observation at PAIS. The natal beach of these two tagged turtles could not be ascertained. However, the documentation of these two individuals indicate some movement of Kemp's ridleys between nesting beaches in Mexico and south Texas. Evidence suggests there is only one genetically distinct stock of this species (Bowen et al. 1991; TEWG 1998), which nests almost exclusively on western Gulf of Mexico shores (Burchfield et al. 1997).

Kemp's ridleys that nest in south Texas today are likely a mixture of returnees from the experimental imprinting and head-starting project and others from the wild stock. They could also include survivors (or their offspring) from hatchlings released in a project started at South Padre Island in 1967 (Francis 1978). As the Kemp's ridley population continues to increase (TEWG 1998) and more turtles from the two egg translocation projects as well as their offspring reach maturity, it is likely that increasing numbers of Kemp's ridleys will come to south Texas to breed and nest. Although it cannot be proven in retrospect, Kemp's ridley nesting may have been more frequent in the USA before over-exploitation of eggs at Rancho Nuevo and incidental capture in shrimp trawls brought the stock to near extinction. Kemp's ridley nesting was documented on the Texas coast long before either of the Rancho Nuevo-to-Padre Island egg translocation projects occurred (Werler 1951; Hildebrand 1963; Carr 1967). In contrast, recent Kemp's ridley nesting records from south Florida (Meylan et al. 1990; Anonymous 1994) and the Carolinas (Palmatier 1993) were outside the known historic nesting range for this species (see Bowen et al. 1994). Also prior to the egg translocation projects, Hildebrand (1963) considered the possibility that scattered nesting of Kemp's ridley along the stretch of coastline from south Texas to Veracruz, Mexico reflected remnants of former Kemp's ridley rookeries. Lack of information about Kemp's ridley nesting in south Texas prior to the late 1940s could have resulted from the paucity of people that lived on and visited south Texas beaches, and misidentification of Kemp's ridleys as other species (Neck 1978; Hildebrand 1982). For example, the south Texas coast may have been an important nesting zone for the green turtle (Chelonia mydas), which was so common in Texas waters prior to the turn of the century that it supported a substantial commercial fishery (Doughty 1984).

Despite Federal regulations requiring turtle excluder devices (TEDs) in shrimp trawls, and repeated assurances by NMFS, the US Coast Guard, and the shrimping industry that compliance with TED regulations is very high, sea turtle strandings on Texas beaches adjacent to the Gulf of Mexico continue to be associated with shrimp fishing in the Gulf along the Texas coast (Shaver 1994b, 1995b, 1996c, 1996d, in press b; Weber et al. 1995; Caillouet et al. 1996). During 1997 alone, there were 90% fewer sea turtle strandings on Gulfside beaches of Texas during the 8-week Texas Closure (when State and Federal waters of the Gulf along the Texas coast were closed to shrimping) than the 8 week periods preceding and following the closure (Shaver in press a). During the last 1.5 years, more adult Kemp's ridleys (i.e., those 60 cm in straight-line carapace length or larger) were documented stranded in Texas than in any other state in the USA or Mexico (Burchfield et al. 1997; Marquez pers. comm.; Teas pers. comm.). Between 1st January 1997 and 22nd June 1998, 42 adult Kemp's ridleys were found stranded on the beaches of the Texas Gulf (including 26 at PAIS). None of the 42 could be linked to the experimental imprinting and head-starting project. However, several lacked front flippers and some carapace scutes, thereby prohibiting a thorough examination for tags. All 42 (15 females, 16 males, 11 undetermined sex) were found dead at times when Gulf waters off the Texas coast were open to shrimping (Shaver in press a). Many of these deaths occurred during the breeding and nesting seasons in 1997 and 1998. Most stranded adult Kemp's ridleys were salvaged and necropsied. Gonads from these individuals were removed and preserved for future analyses to determine breeding condition. However, a few adults were confiscated as law enforcement evidence. No eggs were found in any of the dead females that we examined in 1997 and 1998 (in 1994, one found soon after the Gulf shrimping season opened was gravid).

Adult females are more important than any other life stage with regard to potential immediate contributions toward recovery of the species (Heppell et al. 1996; TEWG 1998). The deaths of adult female Kemp's ridleys in south Texas represents a substantial loss, whether the turtles would have contributed to nesting in south Texas or elsewhere. These deaths may have contributed to a reduction in nesting and production of offspring not only in 1997 and 1998, but also in future years.

As a result of Kemp's ridley restoration efforts started by the Mexican government in 1966 and joined by the USA government in 1978, the Kemp's ridley seems on a course toward recovery (TEWG 1998). The Kemp's ridley population appears to be growing at a rate that may be able to sustain some undetermined levels of loss of adults and other life stages to human causes without preventing recovery or placing the species in immediate jeopardy. However, it might be expected that recovery would accelerate with increased protection from anthropogenic mortalities (TEWG 1998). Nevertheless, the success of efforts to enhance the nesting assemblage of Kemp's ridleys in south Texas as an additional safeguard against extinction depends upon ensuring survival of breeding and nesting turtles in the area. Continued loss of adult Kemp's ridleys in south Texas may cancel out a great deal of long term, costly efforts and may prohibit collection of valuable data needed to assess results of the experimental techniques used in this project. Mexico has declared its primary nesting beach at Rancho Nuevo a refuge for nesting Kemp's ridleys, and has established a no-shrimping zone adjacent to this beach to protect the adults during breeding and nesting seasons (Eckert & Eckert 1993). It is time to give serious consideration to similar protection of the south Texas nesting assemblage of this endangered species, using the Rancho Nuevo refuge and adjacent protected waters as a model.

Acknowledgements: Rene Marquez-M. and Wendy Teas for information on Kemp's ridley strandings and nesting in Mexico and the USA; John Miller, Tony Amos, Don Hockaday, Pat Burchfield and the numerous other individuals that assisted with the detection, investigation, and protection of nesting Kemp's ridleys and their eggs in south Texas; Dickie Revera and Tim Fontaine, who provided information useful in confirming the project origin and year-classes of some of the turtles; numerous Sea Turtle Stranding and Salvage Network participants for their dedicated efforts enabling the documentation of sea turtles found stranded in Texas; the National Park Service, Canon USA, Inc., National Park Foundation, US Geological Survey, US Fish and Wildlife Service, and National Marine Fisheries Service for providing funding to detect and investigate nesting and stranded turtles in south Texas.

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