Natal Origin and Spatiotemporal Distribution of Leatherback Turtle (Dermochelys coriacea) Strandings at a Foraging Hotspot in Temperate Waters of the Southwest Atlantic Ocean.

Leatherback turtles migrate long distances between nesting beaches and distant foraging areas worldwide. This study analyzes the genetic diversity, life history stage, spatiotemporal distribution, and associated threats of a foraging aggregation in the Southwest Atlantic Ocean. A total of 242 leatherbacks stranded or bycaught by artisanal fisheries were recorded from 1997 to 2021 in Uruguay, with sizes ranging from 110.0 to 170.0 cm carapace lengths, indicating that the aggregation is composed of large juveniles and adults. Results of Bayesian mixed-stock analysis show that leatherbacks come primarily from the West African rookeries, based on mitochondrial DNA sequences obtained from 59 of the turtles representing seven haplotypes, including a novel one (Dc1.7). The main threat identified in the area is the fisheries bycatch but most of the carcasses observed were badly decomposed. There was significant seasonal and interannual variability in strandings that is likely associated with the availability of prey and the intensity of the fishing effort. Taken together, these findings reinforce the importance of these South American foraging areas for leatherbacks and the need to determine regional habitat use and migratory routes across the broader Atlantic region, in order to develop effective conservation measures to mitigate threats both at nesting beaches and foraging areas.

Identifying genetic lineages through shape: An example in a cosmopolitan marine turtle species using geometric morphometrics.

The green turtle (Chelonia mydas) is a globally distributed marine species whose evolutionary history has been molded by geological events and oceanographic and climate changes. Divergence between Atlantic and Pacific clades has been associated with the uplift of the Panama Isthmus, and inside the Pacific region, a biogeographic barrier located west of Hawaii has restricted the gene flow between Central/Eastern and Western Pacific populations. We investigated the carapace shape of C. mydas from individuals of Atlantic, Eastern Pacific, and Western Pacific genetic lineages using geometric morphometrics to evaluate congruence between external morphology and species' phylogeography. Furthermore, we assessed the variation of carapace shape according to foraging grounds. Three morphologically distinctive groups were observed which aligned with predictions based on the species' lineages, suggesting a substantial genetic influence on carapace shape. Based on the relationship between this trait and genetic lineages, we propose the existence of at least three distinct morphotypes of C. mydas. Well-defined groups in some foraging grounds (Galapagos, Costa Rica and New Zealand) may suggest that ecological or environmental conditions in these sites could also be influencing carapace shape in C. mydas. Geometric morphometrics is a suitable tool to differentiate genetic lineages in this cosmopolitan marine species. Consequently, this study opens new possibilities to explore and test ecological and evolutionary hypotheses in species with wide morphological variation and broad geographic distribution range.

Conservation status assessment of the amphibians and reptiles of Uruguay

Las especies nativas de anfibios y reptiles de Uruguay fueron categorizadas de acuerdo a los criterios de la Lista Roja de UICN. De las 47 especies de anfibios, siete se encuentran En Peligro Crítico (CR), cinco En Peligro (EN), una Vulnerable (VU), tres Casi Amenazadas (NT), y dos con Datos Deficientes (DD); las especies restantes son consideradas como Preocupación Menor (LC). Entre las 64 especies de reptiles evaluados, una se encuentra en Peligro Crítico (CR), siete En Peligro (EN), dos como Vulnerables (VU), una Casi Amenazadas (NT) y siete con Datos Deficientes (DD); las especies restantes son consideradas como Preocupación Menor (LC). El uso de estos resultados como un criterio adicional en la definición de áreas protegidas en Uruguay contribuirá hacia la conservación de dichas especies amenazadas y sus ecosistemas asociados.

The native species of amphibians and reptiles of Uruguay were categorized according to the IUCN Red List criteria. Out of 47 amphibian species, seven are listed as Critically Endangered (CR), five as Endangered (EN), one as Vulnerable (VU), three as Near Threatened (NT), and two as Data Deficient (DD); the remaining species are considered to be Least Concern (LC). Among the 64 species of reptiles evaluated, one is listed as Critically Endangered (CR), seven as Endangered (EN), two as Vulnerable (VU), one as Near Threatened (NT) and seven as Data Deficient (DD); the rest are considered to be Least Concern (LC). The use of these results as an additional criterion in the definition of protected areas in Uruguay will contribute towards the conservation of the aforementioned threatened species and their associated ecosystems.

Conservation status assessment of the amphibians and reptiles of Uruguay

Las especies nativas de anfibios y reptiles de Uruguay fueron categorizadas de acuerdo a los criterios de la Lista Roja de UICN. De las 47 especies de anfibios, siete se encuentran En Peligro Crítico (CR), cinco En Peligro (EN), una Vulnerable (VU), tres Casi Amenazadas (NT), y dos con Datos Deficientes (DD); las especies restantes son consideradas como Preocupación Menor (LC). Entre las 64 especies de reptiles evaluados, una se encuentra en Peligro Crítico (CR), siete En Peligro (EN), dos como Vulnerables (VU), una Casi Amenazadas (NT) y siete con Datos Deficientes (DD); las especies restantes son consideradas como Preocupación Menor (LC). El uso de estos resultados como un criterio adicional en la definición de áreas protegidas en Uruguay contribuirá hacia la conservación de dichas especies amenazadas y sus ecosistemas asociados.

The native species of amphibians and reptiles of Uruguay were categorized according to the IUCN Red List criteria. Out of 47 amphibian species, seven are listed as Critically Endangered (CR), five as Endangered (EN), one as Vulnerable (VU), three as Near Threatened (NT), and two as Data Deficient (DD); the remaining species are considered to be Least Concern (LC). Among the 64 species of reptiles evaluated, one is listed as Critically Endangered (CR), seven as Endangered (EN), two as Vulnerable (VU), one as Near Threatened (NT) and seven as Data Deficient (DD); the rest are considered to be Least Concern (LC). The use of these results as an additional criterion in the definition of protected areas in Uruguay will contribute towards the conservation of the aforementioned threatened species and their associated ecosystems.