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Descriptions of the developmental stages of embryonic marine turtles are presented in the form of a dichotomous key supported by drawings to facilitate identifying stages of development in the field. The key emphasizes the sequential appearance or loss of external morphological structures that can be seen either with the unaided eye or with a X10 hand lens and a handheld light. Stages are placed in the context of normal beach temperatures to facilitate estimation of laying date, emergence date, and events that cause embryonic mortality. Measurements of embryos are presented to assist determining stage. [ABSTRACT FROM AUTHOR]

This work describes the mycelial fungal diversity associated with leatherback sea turtle nests and eggs from Mayagüez-Añasco Bay Coast (MABC), Puerto Rico. Comparisons are made of conditions previous to leatherback nesting season, during leatherback nesting season, and during nest hatching season. Prior to Dermochelys coriacea nesting season, the fungal community along the MABC showed a normal distribution ( p = 0.098) by One-Way ANOVA. We found that Aspergillus was the most frequent genus (0.15), followed by Cladosporium (0.09) and Curvularia (0.08). At the time of oviposition, Penicillium was the most frequent isolate (0.15), followed by Cladosporium (0.11), Aspergillus (0.11), and Fusarium (0.07). No fungi were isolated from nesting leatherback's ovipositor samples. During hatching season, fungal diversity was evaluated from the sand of hatched nests and from failed eggs. Fusarium solani was the most frequent isolate (0.57) from hatched nest sand and was the only species isolated from the interior of failed eggs. A strong positive correlation was obtained between fungal abundance and the number of failed eggs in the nests ( r = 0.853, p < 0.001). This was the first attempt to study fungal diversity associated with D. coriacea nests and eggs in Puerto Rico. [ABSTRACT FROM AUTHOR]

Florida (United States) beaches serve as globally important nesting habitat for protected species of sea turtles. Following coastal development, portions of this habitat have become inaccessible to nesting sea turtles due to coastal armoring and other barriers. To assess nesting habitat quality, we randomly selected beaches totaling 80.45 km in each of four regions of Florida (northeast, southeast, northwest, and southwest) and surveyed them for potential barriers to nesting during the period of April 2001 to May 2002 (total surveyed coastline 5 321.8 km). Potential barriers to nesting were found in 78 forms on sampled beaches, including seawalls, revetments, sand bags or tubes, sand fences, access structures, recreational equipment, and buildings. We determined the position and extent of structures using a differential global positioning system. Surveyed beaches made up 24.5% of Florida's sandy coastline and were sampled to be regionally representative. In an assessment summed for all regions, potential barriers to nesting occupied 18.0% of the total surveyed beach length. The region with the greatest extent of potential barriers was southeast (23.8%), followed by southwest (21.7%), northwest (14.1%), and northeast (12.3%). Seawalls were the most common potential barriers in all but the northwest region, where sand fences were most common. Our measurements did not include structures that were hidden from view by sand or other structures. Following coastal effects from four major hurricanes that made landfall in 2004, we resurveyed 16 km of beach in each region (total 5 64 km). We recorded a net reduction of sand fencing in northeast and northwest Florida and a net reduction of revetment rocks in the southwest region due to covering by sand. However, the linear extent of barriers increased in northeast and southwest due to seawall construction and additional sand fencing. [ABSTRACT FROM AUTHOR]

Chiriqui Beach, in the Comarca Ngöbe-Buglé on the Caribbean coast of Panama, is the most important nesting beach for leatherback turtles (Dermochelys coriacea) in Caribbean Central America. Beach surveys during the 2003 and 2004 nesting seasons documented 3077 leatherback nests in one season and a minimum of 234 individual leatherbacks. Monitoring of nest fate revealed that predation by dogs represents the greatest human-related survival threat to leatherbacks at Chiriqui Beach, although the killing of leatherbacks from the same nesting population on beaches near the Panama-Costa Rica border also is of concern. [ABSTRACT FROM AUTHOR]

Hatching success for leatherback turtles (Dermochelys coriacea) was low at 4 important nesting beaches in Papua, with high rates of tidal inundation, pig predation, and possible temperature effects. Better protection from pigs and possible nest relocation may be needed to improve hatching success for leather- backs. [ABSTRACT FROM AUTHOR]

Nine leatherback turtles (Dermochelys coriacea) were tracked for 111-695 days via satellite telemetry from one of the largest remaining western Pacific leatherback turtle nesting beaches, Jamursba-Medi, Papua, Indonesia. The turtles moved into tropical waters of the Philippines and Malaysia, into the Sea of Japan, and across the equatorial Pacific to temperate waters off North America. This study provides the first record of a Irans. Pacific migration by a leatherback turtle. [ABSTRACT FROM AUTHOR]

Leatherbacknesting along the Atlantic coast of Africa extends from Mauritania in the north to Angola in the south, with a globally important nesting concentration located in Gabon in Central Africa. Provisional estimates of nesting numbers from Gabon indicate that this nesting population may he among the largest in the world. [ABSTRACT FROM AUTHOR]

Leatherback turtle (Dermochelys coriacea) nesting activity was monitored, individual movements via flipper tag recoveries and satellite telemetry were determined, and illegal egg collection was quantified at Tortnguero, Costa Rica from 1995 to 2006. Annual nest deposition was estimated at 199-1,623 nests per year; a Bayesian regression model suggests that leatherback nesting decreased by 67.8% between 1995 and 2006. Tag recaptures from fisheries bycatch and strandings have been reported from Cuba, Nicaragua. and the United States. Two leatherbacks were followed with satellite telemetry; 1 swam to Cuba and I moved into the northwest Atlantic Ocean. Minimum rates for illegal egg collection from 2000 to 2005 were estimated at 13.0%-21.59%. [ABSTRACT FROM AUTHOR]

Playa Langosta is 1 of 3 nesting beaches in Parque Nacional Marino Las Baulas de Guanacaste, and is 1.3-km long. The 3 beaches (Langosta, Grande, and Ventanas) represent over 6 km of leatherback (Dermochelys coriacea) nesting. The use of passive integrated transponder (PIT) tags allowed us to identify each leatherback that nested at Playa Langosta. A total of 252 individual leatherbacks nested between the 1999-2000 and 2003-2004 nesting seasons. Of these, 63% (n = 158) were new turtles (untagged before), and 50% (n = 79) of the new turtles were originally PIT tagged on Playa Langosta. The majority of these turtles 54%) nested only on Playa Langosta, whereas a slightly smaller percentage (46%) nested at both Playa Grande and Playa Langosta. We recorded 904 encounters and 792 nests at Playa Langosta for the 5 nesting seasons of this study. Leatherbacks nesting at Playa Langosta ranged in curved carapace length from 125 to 164 cm and in curved carapace width, from 90 to 116 cm. Average internesting period was 9.6 days. For the first 4 seasons, data from excavated nests showed a decrease in percentage of hatching success from 68.9% to 30.4% in natural nesting conditions. A dramatic decline to emergence success from 57.2% to 9.3% occurred for these respective seasons. For the last 3 seasons, the hatching success of leatherback turtles in relocated nests was 52.4%, 18.9%, and 51.4%. [ABSTRACT FROM AUTHOR]

Field research was conducted, from 1990 In 2004, at Gaudoca Beach (9°59.972'N. 82°60.530'W). located within the Gandoca-Manzanillo National Wildlife Refuge at the southernmost extreme of the Caribbean coast of Costa Rica. Nightly patrols of the 8.85-km nesting beach were undertaken annually from the second week of February through the last week of July, and pertinent information regarding the nesting process was recorded. An estimated 90% of all nesting females were documented and uniquely tagged; these 2751 females deposited 8766 nests (believed to he a complete count). Averaged over the 15-year study period. 12.5% of all nests were left unaltered in situ; 12.9% were left in situ, with tracks camouflaged by beach patrollers; 33.9% were relocated to lower risk zones on the beach; and 25.4% were relocated to beach hatcheries. Poaching, which had once claimed nearly 100% of all eggs laid, averaged 15.5% annually during the study period, demonstrating a clearly declining trend, attributable to the presence of beach patrollers, policies associated with the wildlife refuge, and changing attitudes within proximal communities. A comparison of tag registries indicates an interchange of gravid females among nesting beaches both within Costa Rica and internationally with Panama and Colombia. The interchange reinforces the importance of joint efforts to address primary threats, including beach erosion, egg poaching, direct harvest of adults for meat (especially in Panama), and coastal development. The population is statistically stable but shows a steadily declining trend to the number of nests laid since 2000. [ABSTRACT FROM AUTHOR]

From 1985 to 1999, data were gathered opportunistically on the bycatch of 33 leatherback turtles in coastal Peru, and from 2000 to 2003, a dockside observer program provided data on an additional 133 leatherbacks caught in the coastal gilluet and longline fisheries targeting mahi mahi, sharks, and rays. These data stress the need for programs to monitor bycatch in artisanal fisheries. enforce regulations prohibiting sea turtle capture, and increase the environmental awareness of fishermen. [ABSTRACT FROM AUTHOR]

Suriname beaches support a major nesting colony of leatherback turtles. During the 1999-2005 nesting seasons, we collected data on nesting ecology and identified individual turtles that nested at Babunsanti (Galibi Nature Reserve), Samsambo, Kolukumbo, and Matapica. We observed 8462 leatherback females, 6933 of which we PlT-tagged. The remaining 1529 females carried PIT tags of a non-Surinamese origin. Because complete coverage of all nesting beaches was not possible over the study period, estimations of minimum annual nesting colony size were made, which ranged from 1545 to 5500 females in Suriname alone. Of the 7394 turtles observed during 1999-2004, 14.8% were seen renesting by 2005. Annual mean internesting period ranged between 9.4 ± 1.0 to 9.6 ± 1.0 days. Annual mean observed clutch frequency was between 1.6 ± 1.0 to 3.1 ± 1.4 and annual minimum estimated clutch frequency between 4.1 ± 1.6 to 4.9 ± 1.8 clutches. Annual mean standard curved carapace length ranged from 154.1 ± 6.7 to 155.6 ± 6.7 cm, and annual mean clutch size ranged from 80.8 ± 18.3 to 88.2 ± 19.5 yolked eggs. Annual average hatch success (including nests with zero batching) ranged from 10.6% ± 16.4 to 25.8% ± 24.4 at Babunsanti, and from 52.7% ± 29.7 to 56.0% ± 30.8 at Matapica. Remigrants and non-Surioamese turtles were, on average, larger than new females, and remigrants had a higher clutch frequency. In 6 years, the annual proportion of newly tagged females decreased from 89.9% to 40.5% and that of remigrants increased from 0% to 45.6%. However, the annual proportion of turtles with a nun-Surinamese PIT tag (10.1% to 17.6%) was relatively stable. Combined with the moderate frequency of intra- and interseasonal nesting exchange between regional beaches, this indicates that although the Suriname/French Guiana leatherbacks form a single rookery, individual females show strong nesting fidelity to one side of the Marowijne Estuary. [ABSTRACT FROM AUTHOR]

We describe a low-risk, alternative technique for sampling blood from leatherback turtles (Dermochelys coriacea) using interdigitary vessels in their flippers. Because this technique allows for repeated, large-volume blood samples without requiring restraint of turtles, the technique is preferred over using the dorsal cervical sinus in almost all cases of blood sampling from leatherbacks, and also applies to other sea turtle species. [ABSTRACT FROM AUTHOR]