ABSTRACT: Hybridization is a fundamental evolutionary and ecological process with significant conservation ramifications. Sea turtle hybridization occurs at unusually high frequencies along the northeastern coast of Brazil. To better understand the process, we studied the reproductive output, migration patterns (through satellite telemetry), and isotopic niches of loggerhead turtles Caretta caretta and olive ridley turtles Lepidochelys olivacea and their hybrids. We classified 154 nesting females as loggerhead (n = 91), olive ridley (n = 38), or hybrid (n = 25) based on mitochondrial and nuclear DNA. Further, we compared nesting female morphological data and reproductive parameters (clutch size, emergence success, hatchling production, incubation period) of 405 nests among hybrids and parental species. We found no significant differences among the 3 groups when hatchling production was corrected for female body size, indicating that hybrids and parental species produce similar numbers of hatchlings per clutch. Satellite tracking of 8 post-nesting hybrid females revealed shared foraging grounds with both parental species, as well as neritic migrations between foraging and nesting areas similar to those previously reported for loggerheads and olive ridleys. Analyses of ¹³C and ¹⁵N isotope values (n = 69) further confirmed this pattern, as hybrid isotopic niches overlapped extensively with both parental species. Thus, given the similarities presented between hybrids and their parental species in reproductive, ecological, and behavioral characteristics, we conclude that these hybrids may persist along with other sea turtle nesting populations in the area, with research and conservation implications.

中文翻译：

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巴西奥利德利和海龟及其杂种的繁殖产量，觅食目的地和同位素生态位

摘要：杂交是一个基本的进化和生态过程，具有重要的保护意义。海龟杂交发生在巴西东北海岸的异常高频率。为了更好地了解这一过程，我们研究了龟，etta龟和橄榄色ley鱼的繁殖产量，迁移模式（通过卫星遥测）和同位素iso和他们的杂种。根据线粒体和核DNA，我们将154位筑巢雌性分为（n = 91），橄榄色ridley（n = 38）或杂种（n = 25）。此外，我们比较了405个巢穴在杂种和亲本物种之间的筑巢雌性形态学数据和生殖参数（离合器大小，出苗成功，孵化产量，潜伏期）。当根据女性的体型校正孵化量时，我们发现三组之间没有显着差异，表明杂种和亲本物种每个离合器产生的孵化量相似。卫星跟踪了8个嵌套后的杂交雌性，发现它们与亲本物种共享觅食地，并且觅食和筑巢区之间的野外迁移与先前报道的高头和橄榄色ridleys相似。分析¹³ C和¹⁵ N同位素值（n = 69）进一步证实了这种模式，因为杂种同位素壁ni与两个亲本物种都广泛重叠。因此，鉴于杂种及其亲本物种在生殖，生态和行为特征上的相似性，我们得出结论，这些杂种可能与该地区其他海龟筑巢种群一起存在，具有研究和保护意义。