Charles Kate E, Morrall Clare E, Edwards Jonnel J, Carter Kenrith D, Afema Josephine A, Butler Brian P, Marancik David P
Department of Pathobiology, School of Veterinary Medicine, St. George's University, True Blue, West Indies, Grenada.
Ocean Spirits, Inc., West Indies, Grenada.
Animals (Basel). 2023 Feb 16;13(4):685. doi: 10.3390/ani13040685.
Annual monitoring of leatherback sea turtle () nesting grounds in Grenada, West Indies has identified relatively low hatch rates compared to worldwide trends. This study investigated the impact of selected environmental variables on leatherback sea turtle embryonic development and hatching success rates on Levera Beach in Grenada between 2015-2019. The mean number of nests per year and eggs per nest were 667.6 ± 361.6 and 80.7 ± 23.0 sd, respectively. Within excavated nests, 35.6% ± 22.0 sd of eggs successfully developed embryos and 30.6% ± 22.6 sd of eggs successfully hatched. The number of eggs per nest, along with embryo and hatching success rates, differed by nesting year. Embryo development success rate was associated with nest location, and both embryo development and hatching success rates were positively associated with nest depth and negatively associated with the percentage of eggs exhibiting microbial growth and with the presence of inspissated yolk. There was no embryo development or hatchling success association with month of the nesting season, distance from the high-water mark, distance from vegetation, nor maternal carapace length. The mean nest temperature was 31.7 °C ± 1.64 sd and mean temperatures during the middle third of egg incubation suggest clutches are highly skewed towards a preponderance of female hatchlings. Histopathologic findings in hatchling mortalities included severe, acute, multifocal, heterophilic bronchopneumonia with intralesional bacteria in 4/50 (8%) hatchlings. Data from this study guide conservation strategies by identifying risk factors and further avenues of research needed to support reproductive success of leatherback sea turtles in Grenada and the greater Caribbean region.
对西印度群岛格林纳达棱皮龟（）筑巢地进行的年度监测发现，与全球趋势相比，孵化率相对较低。本研究调查了2015年至2019年间格林纳达莱维拉海滩上选定的环境变量对棱皮龟胚胎发育和孵化成功率的影响。每年的平均巢穴数量和每个巢穴的平均卵数分别为667.6±361.6和80.7±23.0标准差。在挖掘出的巢穴中，35.6%±22.0标准差的卵成功发育成胚胎，30.6%±22.6标准差的卵成功孵化。每个巢穴的卵数以及胚胎发育和孵化成功率随筑巢年份而不同。胚胎发育成功率与巢穴位置有关，胚胎发育和孵化成功率均与巢穴深度呈正相关，与出现微生物生长的卵的百分比以及浓稠蛋黄的存在呈负相关。胚胎发育或幼龟孵化成功率与筑巢季节的月份、距高水位标记的距离、距植被的距离以及母龟背甲长度均无关联。平均巢穴温度为31.7°C±1.64标准差，卵孵化中期的平均温度表明，孵化出的幼龟大多偏向雌性。幼龟死亡的组织病理学发现包括4/50（8%）的幼龟出现严重、急性、多灶性、嗜异性支气管肺炎，病灶内有细菌。本研究的数据通过识别风险因素以及支持格林纳达和大加勒比地区棱皮龟繁殖成功所需的进一步研究途径，为保护策略提供了指导。
