Sea turtle species observed nesting at the US Naval Station at Guantanamo Bay, Cuba (GTMO) include greens (Chelonia mydas) and hawksbills (Eretmochelys imbricata), both of which are classified as endangered by the World Conservation Union (IUCN). As Cuba and its neighbors continue to develop their coasts, all efforts should be made to preserve this important nesting refuge. Habitat suitability index models are one tool with which managers can generate hypotheses and experiment with management options. This study used an observational dataset of nests and measured habitat variables to develop habitat suitability index models in a geographic information system. The first objective was to compare the performance of 3 different habitat model-building approaches in order to determine which technique, if any, provides reliable information on sea turtle nesting habitat preferences. A habitat suitability index score for each beach zone was computed using 1) suitability indices with expert weights, 2) unscaled environmental variables with regression-based weights, and 3) a combination of suitability indices with regression-based weights. The second objective was to use the models to lend insight into important environmental descriptors of suitable sea turtle habitat for GTMO. All models predicted moderately well with 40% prediction rates, even though they assigned different weights to the variables. Moderate model performance may be attributed to low samples sizes and/or nest site fidelity that is unrelated to environmental factors. Overall, differences between empirical and expert model results reflect a shift from a regional (Caribbean) to a local scale of analysis (GTMO). However, in all models, compaction of the substrate was almost twice as influential as the other variables, indicating that the looser the sand, the more suitable the habitat. Conservation implications and suggestions for future research are discussed.

Field Island in Kakadu National Park, Northern Territory, Australia, supports a nesting population of flatback turtles (Natator depressus) monitored since 1990. We summarize 9 years of survey data for this location and make recommendations for future research. At least 221 nesting flatbacks were tagged at Field Island between 1990 and 2001. Nightly emergence rates indicate that Field Island is a locally and regionally important rookery for flatbacks with no other species recorded nesting. The mean interseasonal remigration period was 2.82 years. Female flatbacks laid clutches of similar sizes to those reported for other Australian rookeries, but nests tended to be deeper than those on nearby mainland beaches. No evidence of size decline (curved carapace length) occurred over the years, and mean curved carapace length was similar to those observed at other nesting rookeries. The amount of biological information now available for the Field Island rookery and the number of nesting turtles already tagged makes it valuable as an index site for flatback turtles in northern Australia.

Reproduction and nesting in the ringed map turtle (Graptemys oculifera) were investigated in the Pearl River of west-central Mississippi in 1995 and 1996. Nesting occurred from mid-May until mid-July but peaked in mid-June. Minimum carapace length of females at sexual maturity was 130 mm, but mean size at maturity was between 130 and 140 mm. Mean and modal CSs were 3.7 and 3. Larger females were gravid earlier than smaller ones and both egg and CS declined as the nesting season progressed. CS was positively correlated with both female carapace length and body mass. Mean egg length, width, and mass were 38.8 mm, 22.7 mm, and 11.8 g, respectively. Hatchlings averaged 35.5 mm carapace length and 8.9 g in mass. Annual clutch frequency may range from 0.96 to 1.42, and a minimum of ca. 60% of females reproduced on an annual basis. Predators destroyed an average of 86% of nests each year. Major vertebrate nest predators were armadillos, raccoons, and fish crows. Invertebrate egg predators destroyed an additional 24% of eggs known to be fertile.

This study investigated the effects of hatchery shading, nest depth, and metabolic heating on the temperature of Chelonia mydas clutches incubated in hatcheries at Ma'Daerah, Terengganu, Malaysia. Metabolic heating was found to be the most influential factor on nest temperature; the number of completely developed eggs explained nearly half of the variation in mean nest temperature. The degree of hatchery shading (70% vs. 100%) and nest depth (50 vs. 75 cm) had little influence on nest temperatures, with mean nest temperatures between 28° and 28.6°C in the first third of incubation (before metabolic heating of the clutch began to have an effect). Nests at a depth of 75 cm had significantly lower daily temperature ranges than nests at a depth of 50 cm, but a maximum mean daily range of 0.5°C (50 cm depth in 70% shade hatchery) resulted in calculated constant temperature equivalents (CTE) being identical to observed mean nest temperatures. The results of this study indicate that, under current climatic conditions in this area, shading between 70% and 100% and nest depths between 50 and 75 cm will incubate green turtle clutches within the optimal temperature range for development. However, this information is site-specific and could vary significantly between locations due to the complex interaction of biological, chemical, and physical factors that influence sea turtle nest temperature.

Based on museum and stranding records, leatherback turtles (Dermochelys coriacea) were previously considered a rare migrant in South Carolina nearshore waters with only 9 recorded prior to 1980. In 1989, leatherback sightings increased, both alive and dead, in large numbers. From 1980 to 2003, 141 leatherback carcasses stranded. These leatherback strandings were highly seasonal, with a major peak in spring and a minor peak in fall. Based on 23 necropsies, there were 7 males and 16 females (1:2.3). From 1994 to 2003, during April–June, 1131 live leatherbacks (0.04 per km) were observed during 50 nearshore aerial surveys flown parallel to the South Carolina coast. The highest concentration during a single flight was in May 2002, with 175 leatherbacks seen over 605 km of transect line or 0.29 per km. Leatherbacks were not randomly or uniformly distributed, but had a contagious (clumped) distribution. Numbers observed varied significantly between inner and outer transect lines, among years, and among flights within a year. These lines of evidence demonstrate the recent occurrence, spatial distribution, and temporal variability of leatherbacks in South Carolina nearshore waters.

By using 6 years of Long Term Resource Monitoring Program (LTRMP) turtle by-catch data collected from the middle Mississippi River, we investigated smooth softshell (Apalone mutica) and spiny softshell (Apalone spinifera) turtle abundance collected from 5 physical habitats: main channel border, wing dikes, tributary, open side channel, and closed side channel. Females comprised 62% and males 38% of the total catch of smooth softshell turtles. For spiny softshell turtles, females comprised 67% and males 33% of the total catch. We observed skewed reproductive age structure and sex ratios among and within both species. Smooth and spiny softshell turtle captures were dominated by reproductive individuals (62% and 87%, respectively). Smooth softshell turtles were most abundant in open side channels and main channel borders, whereas spiny softshell turtles were most abundant in tributaries and closed side channels. Smooth softshell abundance was greatest in deep waters with faster water velocity, whereas spiny softshell abundance was greatest in waters with higher visibility (e.g., Secchi transparency) and slower water velocity.

We used genetic data from 7 microsatellite loci to determine the frequency of multiple paternity in clutches of giant Amazon river turtles, Podocnemis expansa, from the Orinoco River in Venezuela. Among hatchlings sampled from 32 clutches, paternity analysis found that a minimum of 10.3% could conclusively be shown to have been sired by more than one male. We contrast this result with those from another population of this species, as well as other species of turtles, and discuss the importance of documenting patterns of paternity in different populations of a given species and considering the effects of ecological differences among populations on female mating behavior.

We tracked 10 leatherback turtles by satellite from 2 Florida Atlantic Coast nesting beaches for a period ranging from 38 days to more than 454 days. Movement and foraging areas were often coastal, which contrasts with other satellite telemetry studies where leatherbacks are more pelagic. Using kernel home-range estimation we identified the primary internesting residence areas as well as Atlantic foraging areas. The primary internesting habitat was centered east–southeast of Cape Canaveral, Florida, from 2 to 60 km offshore and extending 215 km along the coast. Atlantic foraging areas were located primarily on the continental shelf from 30° to 50°N, and in an offshore area centered at 42°N, 65°W, as well as off Africa in the Mauritania upwelling. Seasonally, the location of these foraging areas changed, occurring on the North American continental shelf from March through November and off the shelf from December through February. One of the tracked turtles may have been killed with 17 other leatherbacks by coastal shrimp fishing located near the Georgia–Florida border. We illustrate how using remotely sensed data could be used to prevent such mortalities.

Nest-site selection by female Trachemys callirostris callirostris was studied on an island in the Pijiño wetland of the Mompos Depression of Colombia. We quantified distances of nests to the shoreline and compared vegetative cover and soil types at nest locations and at randomly selected points on the island. Nests sites were concentrated in the first 5 m from the shoreline and were always located under vegetative cover. Such cover might reduce thermal stress to nesting females, lower the probability of nest detection by predators, and buffer the incubating eggs from environmental extremes. Females preferentially nested under water hyacinth, but it was not clear whether they selected directly for this vegetative cover type or simply preferred dirt substrates where it dominated, because dirt soils contained higher humidity.

On many nesting beaches, hatchling marine turtles are exposed to poled street lighting that disrupts their ability to crawl to the sea. Experiments were done to determine how hatchlings responded to street lighting transmitted through 2 filters that excluded the most disruptive wavelengths (those < 530 nm; those < 570 nm). Filtered lighting, however, also attracted the turtles though not as strongly as an unfiltered (high-pressure sodium vapor) lighting. Filtering is therefore of limited utility for light management, especially since other alternatives (such as lowering, shielding, or turning off unnecessary lighting; use of dimmer lights embedded in roadways) are more effective.

Mitochondrial DNA (mtDNA) sequences were determined for 168 green turtles (Chelonia mydas) nesting at the 3 known rookeries in Brazil: Trindade (n = 99), Atol das Rocas (n = 37), and Fernando de Noronha (n = 16). In addition, 32 green turtles were sampled on foraging grounds at Atol das Rocas and Fernando de Noronha. Significant genetic structure exists among the 3 rookeries, with haplotype frequencies significantly different between Trindade and the other 2 rookeries, and no significant difference between Atol das Rocas and Fernando de Noronha. In contrast to previous reports, we found no significant relationship between population size and mtDNA diversity when 14 Atlantic green turtle rookeries were compared for 3 measures of diversity. There was also no significant relation between rookery latitude and mtDNA diversity. Our results are consistent with the earlier hypothesis that haplotype CM-A8 is the closest relative to an ancestral Atlantic haplotype and the observation that CM-A8 is the most common and widespread haplotype in equatorial rookeries. Bayesian and hierarchical mixed stock models yielded similar estimates of rookery contributions to the Atol das Rocas and Fernando de Noronha foraging aggregation, with Ascension Island the primary source and with probable contributions from the Greater Caribbean and West Africa. This study provides data from the southwest Atlantic that are critical for an Atlantic-wide analysis of green turtle population structure.

Diet quality and body size affected passage time of 2 diets (higher and lower in fiber) in hatchling and juvenile desert tortoises (Gopherus agassizii). Mean retention time of the liquid fraction of each diet was significantly shorter than that of the solid fraction, and hatchlings had shorter passage times than juveniles. Habitat disturbances that limit access of hatchlings to diets lower in fiber may negatively impact the physiological and behavioral ecology of young desert tortoises.

Fly larvae were collected from a northern map turtle (Graptemys geographica) nest in which the eggs failed to hatch. The flies were identified as the seed corn maggot, Delia platura (family Anthomyiidae), a widespread phytophagous or saprophagous species in North America that is unlikely to have been a factor in nest failure. Thus, not all fly larvae encountered within turtle nests are the cause of mortality.

A shrimp trawl fishery study was conducted in the coastal waters of Orissa, India, from November 2001 to March 2002; 76 trawls in water of 6–35 fathoms resulted in the capture of 26 olive ridley turtles (Lepidochelys olivacea). Most turtle captures occurred within 5 km of the shoreline and at a depth of less than 10 fathoms, emphasizing the need for greater protection of these nearshore habitats. Data revealed a strong relationship between tow time and mortality of turtles.

We investigated the reproductive biology of Podocnemis sextuberculata in the Reserva Biológica do Rio Trombetas, state of Pará, Brazil. Female carapace length was positively correlated with number, average weight, and volume of eggs. Clutch size varied from 8 to 24 eggs, incubation period varied from 48 to 64 days, and hatching occurred about 1 month before the beginning of the rainy season. Local inhabitants regularly use females, nests, and neonates as food sources.

Hawksbill turtles (Eretmochelys imbricata) are cleaned and followed by reef fishes at Fernando de Noronha Archipelago, off northeast Brazil. During foraging, turtles are cleaned by damselfishes (Abudefduf saxatilis and Stegastes rocasensis), and followed by juvenile wrasses (Thalassoma noronhanum and Halichoeres radiatus).

Beaches at Ras Al-Hadd Reserve, Oman, share common physical features ideal for nesting green turtles (Chelonia mydas). However, human activities related to commercial fishing and coastal development impact nesting. Beaches with hills as a backdrop and with minimal human activities were the primary nesting sites at the reserve. During peak nesting season (monsoon/wet period), the mean number of excavation attempts was equal between oviposited and nonoviposited turtles. During nonpeak season (dry period), the mean number of excavation attempts was significantly higher in nonoviposited turtles than in oviposited turtles, and insufficient sand moisture frequently resulted in one or several nest collapses and oviposition failure.

We incubated eggs of the Chinese three-keeled pond turtle (Chinemys reevesii) at 4 constant temperatures to assess the influence of these thermal regimes on incubation length, hatching success, and phenotypic traits of hatchlings. Eggs incubated at 24° and 27°C produced larger hatchlings in body mass, carapace size, and limb length than did those from 30° and 33°C. Hatchlings from 27° and 30°C crawled and swam faster than did their counterparts from 24° and 33°C. The critical thermal minima of hatchlings incubated at 30° and 33°C were higher than those of hatchlings from 24° and 27°C.

Female green turtles (Chelonia mydas) were monitored for signs of throat movements/oscillations when attempting to nest at Ascension Island in the S5outh Atlantic. Throat oscillations occurred during all stages of the nesting process, with the mean frequency ranging from 10.9 to 36.1 oscillations/min, while the mean breathing rate for different stages during nesting activity ranged from 1.3 to 2.8 breaths/min.

We update the status and conditions of Chelonia mydas nesting on Samandağ Beach, Turkey, for 2001 and 2002, and compare our data to previous monitoring efforts. We recorded 20 nests in 2001 on 1 section of the beach and 118 nests in 2002 on the entire beach. Data on these nests and resultant hatchings are presented, including an assessment of habitat threats to the nesting beach.

This research was conducted to determine a potential relationship between fibropapillomatosis (FP) and basking behavior in green turtles (Chelonia mydas) in Hawaii. Only turtles with FP were observed basking, and basking resulted in increased body temperature of 2.9°C above ambient.

We characterized the microhabitat features of nests constructed by eastern box turtles, Terrapene carolina carolina, in central Illinois. All nests were sited in open habitats; 87.5% of them were depredated within 72 hours of oviposition. Nest sites differed from random sites in vegetation height and composition, percentage ground and canopy cover, and light intensity. Land management practices that provide open areas suitable for box turtle nesting activity might make these areas more attractive to potential nest predators.

Stomach contents of Podocnemis unifilis sampled in white water varzéa forest during the dry season in the Mamirauá Sustainable Development Reserve (Middle-Solimões River) had plant material in 100% of cases, with Poaceae and Bombacaceae the most frequently recorded. Poaceae leaves (67.7% frequency) and seeds (21.5% frequency) were common, as were fibers of the fruit Pseudobombax munguba (Bombacaceae; 38.5% frequency), with fruits in general contributing 45.9% of volume. Animal material was consumed in much lesser quantities—only 0.8% of total volume—but had a 37% frequency.

We examined variation in claw length of hatchling and adult red-eared slider turtles (Trachemys scripta elegans). Hind claw length of adult females was greater than that of adult males, and we suggest that increased hind claw length in females (a previously unrecognized sexually dimorphic trait) may serve as an adaptation for nest construction. In addition, front and hind claws of hatchlings newly emerged from their eggs were longer than the front and hind claws of hatchlings that were captured during their migration toward aquatic habitats; relatively long claws could aid hatchlings in their escape from nests and migration to aquatic habitats.

A field survey of the Sulawesi forest turtle (Leucocephalon yuwonoi) in north-central Sulawesi demonstrates that the species is collected by turtle hunters, and population densities are relatively low. Several new localities for the species and data on reproduction, habitat, and parasites are reported in this article.

Historical records for Pelochelys cantorii from Borneo are reviewed, and the first record of the species from Sabah is described.