Kemp's Ridley Turtles Research Articles

Relative Abundance, Temporal Patterns, and Growth of Sea Turtles at the Mansfield Channel, Texas

Species composition, relative abundance, residency, seasonality, size classes, and growth of sea turtles at the Mansfield Channel, Texas were investigated from 1989-1992. Forty-three juvenile green turtles (Chelonia mydas) (N = 72 captures) and one juvenile hawksbill turtle (Eretmochelys imbricata) (N = 1 capture) were netted during 435 hours of year-round effort (1.38 turtles/km-h). Eighteen of the green turtles (42%) netted were subsequently recaptured, with a mean interval from first to last capture of 120 days (range 22-478 days). However, few of the individuals initially netted between September and February or measuring more than 35 cm straight-line carapace length at initial capture were recaptured. Collectively, green turtles were caught during all months except January. Catch-per-unit-effort was pos- itively correlated with water temperature, air temperature, and water salinity and most green turtles were captured during early morning and late afternoon hours. The Mansfield Channel may provide foraging and resting habitat for both itinerant and seasonally resident green turtles. Juvenile Kemp's ridley (Lepidochelys kempi), green (Chelonia mydas), and loggerhead (Caretta caretta) sea turtles are found within inshore wa- ters of New York, Virginia, and Florida, areas which may serve as important developmental habitats (Mendonca and Ehrhart, 1982; Lutca- vage and Musick, 1985; Byles, 1988; Withering- ton and Ehrhart, 1989; Burke and Standora,

PCBs and other chlorinated organic contaminants in tissues of Juvenile Kemp's Ridley Turtles ( Lepidochelys kempi)

Concentrations of PCBs (polychlorinated biphenyls) and chlorinated pesticides were measured in liver and body fat samples of juvenile Kemp's ridley sea turtles ( Lepidochelys kempi). These turtles were killed in the fall or early winter by rapid seasonal temperature drops and were collected on the eastern shores of Long Island from 1980 to 1989. These endangered organisms contained average PCB concentrations (on a wet weight basis) ranging from 655 ng/g in 1980 to 272 ng/g in 1989 in the liver samples, and 1250 ng/g in 1985 to 476 ng/g in 1989 in body fat. The average liver concentrations were four to ten times higher than those found in the livers of other sea turtles. The highest PCB concentration found in a Kemp's ridley turtle was more than a factor of 20 below those reported to cause reproductive effects in snapping turtles (Chelydra serpentina) from freshwater environments. Average yearly concentrations of other compounds in the tissues of Kemp's ridley turtles ranged from 137 to 386 ng/g (wet weight) for p, p′-DDE and from 27.5 to 129 ng/g (wet weight) for trans-nonachlor. Strong correlations were found between liver and body fat concentrations for PCBs ( r 2 = 0.90), p, p′-DDE ( r 2= 0.80) and trans-nonachlor ( r 2= 0.93) which suggested that either tissue may be used for monitoring these contaminants in Kemp's ridley turtles.

Diet of Juvenile Kemp's Ridley and Loggerhead Sea Turtles from Long Island, New York

Diet of Juvenile Kemp's Ridley and Loggerhead Sea Turtles from Long Island, New York

Factors Affecting Strandings of Cold-Stunned Juvenile Kemp's Ridley and Loggerhead Sea Turtles in Long Island, New York

Factors Affecting Strandings of Cold-Stunned Juvenile Kemp's Ridley and Loggerhead Sea Turtles in Long Island, New York

Occurrence of Immature Kemp's Ridley Turtles, Lepidochelys kempi, in Coastal Waters of Northwest Florida

Occurrence of Immature Kemp's Ridley Turtles, Lepidochelys kempi, in Coastal Waters of Northwest Florida

Feeding Ecology of Wild and Head-Started Kemp's Ridley Sea Turtles in South Texas Waters

Digestive tract contents were examined from 101 dead Kemp's ridley turtles, Lepidochelys kempi, found stranded on south Texas beaches from 1983-1989. Fifty turtles were wild and 51 had been head-started (captively-reared) for 6-9 months. Fifty-one were found on bay (inshore water) and 50 on Gulf of Mexico (offshore water) shorelines. Ogren (1989) stated that juveniles ( 60 cm carapace length) are predominately benthic feeders and eat mostly crabs. It appears, from analysis of gut contents, that wild and head-started turtles are foraging in water depths of less than 50 m and that they will consume items discarded from shrimp trawls and smaller trawls fishing for bait items. Significant differences occur between various dietary parameters measured for wild and post-release headstarted turtles. However, there are similarities between the diets of both groups and head-started turtles appear to be adapting to feeding in the wild. Size and habitat differences are primary causes of dietary divergences among L. kempi. Although knowledge of food items can provide valuable information on dietary preferences, foraging habitats, activities, and movements of a species, the diet of the critically endangered Kemp's ridley (Lepidochelys kempi) is poorly known (Mortimer, 1981) and has not been studied extensively. The little information available has been derived from qualitative examination of the digestive tract contents of a few geographically scattered samples (DeSola and Abrams, 1933; Carr, 1942; Smith and List, 1955; Dobie et al., 1961; Hardy, 1962; Lutcavage, 1981; Lutcavage and Musick, 1985). Virtually nothing is known about foraging by head-started Kemp's ridley turtles. Headstarted turtles are reared in captivity for the first year of life to increase their survival and subsequently released (Manzella et al., 1988). Approximately 15,000 turtles (about 1500/year) were head-started at the National Marine Fisheries Service Laboratory, Galveston, Texas from 1978-1988. During rearing, they were fed a 327 This content downloaded from 207.46.13.85 on Sat, 28 May 2016 05:33:59 UTC All use subject to http://about.jstor.org/terms

Potential impact on sea turtles, dolphins, and fishes of explosives used in offshore platform removals

A high incidence of strandings of sea turtles, bottlenose dolphins, and fishes was recorded on the beaches in the northwestern Gulf of Mexico during March–June 1986, when explosives were used to remove several oil platforms in adjacent offshore waters. Prior to, during, and after March–June of the following year, 1987, strandings for the same area were significantly lower, or negligible. Recovery locations of drift bottles released at the site of the explosions were correlated with some of the strandings. Wild turtles and bottlenose dolphins were observed in the vicinity of the platforms during removal operations. Abnormal (stunted) Kemp's ridley and loggerhead sea turtles were placed at various distances from platforms and exposed to explosions. Preliminary results from exposure studies, including the death of a Kemp's ridley 50 yards from the explosion and an unconscious loggerhead turtle approximately 1000 yards from the explosion, are described. Allowing for in‐bottom loss, received sound‐pressure levels were calculated to be 235 dB (50 yards) and greater than 200 dB where a caged loggerhead was found unconscious.

Wildlife in Surinam

Surinam is one of the few countries in the world where uninhabited and undisturbed tropical rain forest still covers large areas. The Government is fully aware of the importance of this natural heritage. Wildlife is protected, and eight nature reserves, ranging in size from 4000 to 22,000 ha, have been created to protect representative habitats – forest, savannas, coastal flats and important breeding beaches for Kemp's ridley, green and leatherback turtles.

Renal ultrastructure and excretion of salt and water by three terrestrial lizards.

Renal ultrastructure and excretion of salt and water by three terrestrial lizards.

Excretion in fresh-water turtle (Pseudemys scripta) and desert tortoise (Gopherus agassi)

Excretion in fresh-water turtle (<i>Pseudemys scripta</i>) and desert tortoise (<i>Gopherus agassi</i>)