Marine turtles undertake long migrations across different geographies and habitats, exposing them to a wide range of threats throughout their lifespan. Analysing population structure and connectivity is key to informing effective conservation management. We expand knowledge of Atlantic-wide connectivity of green turtles ( Chelonia mydas ) by characterising the genetic structure of the Ascension Island nesting population, one o...

Introduction Loss of biodiversity in marine ecosystems is a globally acknowledged problem. To address this and avoid extinctions, improved conservation is required to protect and restore our oceans. Elasmobranch species are considered the second most threatened vertebrate lineage, with overfishing considered the most important driver of declines. The Mediterranean Sea is a hotspot for elasmobranchs, with the eastern basin cons...

Loggerhead turtles are a globally vulnerable species of marine turtle. Broad-scale patterns of distribution and abundance can provide regional managers a tool to effectively conserve and manage this species at basin and sub-basin scales. In this study, combined aerial and shipboard line transect survey data collected between 2003 and 2018 were used to estimate distribution and abundance throughout the Mediterranean Sea. Approx...

Small-scale fisheries (SSFs) are often undervalued and unmanaged as a result of a lack of data. A study of SSFs in Menabe, western Madagascar in 1991 found diverse catches and a productive fishery with some evidence of declining catches. Here we compare data collected at the same landing site in 1991 and 2011. 2011 had seven times greater total monthly landings due to more people fishing and higher individual catches. Catch co...

Aim The body size of marine megafauna can influence population dynamics because larger females have disproportionally greater reproductive output. We explored how this size scaling relationship can affect predictions of population size structure in nesting sea turtles by combining a phylogenetically controlled meta‐analysis with a long‐term field nesting survey. Location Global (meta‐analysis) and Malaysia (field survey). Time...

The ingestion of plastic by marine turtles is now reported for all species. Small juvenile turtles (including post-hatchling and oceanic juveniles) are thought to be most at risk, due to feeding preferences and overlap with areas of high plastic abundance. Their remote and dispersed life stage, however, results in limited access and assessments. Here, stranded and bycaught specimens from Queensland Australia, Pacific Ocean (PO...

Dietary studies provide key insights into threats and changes within ecosystems and subsequent impacts on focal species. Diet is particularly challenging to study within marine environments and therefore is often poorly understood. Here, we examined the diet of stranded and bycaught loggerhead ( Caretta caretta ) and green turtles ( Chelonia mydas ) in North Cyprus (35.33° N, 33.47° E) between 2011 and 2019. A total of 129 tax...

Given differing trajectories of sea turtle populations worldwide, there is a need to assess and report long-term population trends and determine which conservation strategies are effective. In this study, we report on sea turtle nest monitoring in the Cayman Islands over a 22-year period. We found that green ( Chelonia mydas ) and loggerhead ( Caretta caretta ) nest numbers increased significantly across the three islands sinc...

Bycatch is one of the key threats to juvenile marine turtles in the Mediterranean Sea. As fishing methods are regional or habitat specific, the susceptibility of marine turtles may differ according to inter- and intra-population variations in foraging ecology. An understanding of these variations is necessary to assess bycatch susceptibility and to implement region-specific management. To determine if foraging ecology differs...

Coastal areas provide critical nesting habitat for marine turtles. Understanding how artificial light might impact populations is key to guide management strategies. Here we assess the extent to which nesting populations of four marine turtle species—leatherback ( Dermochelys coriacea ), olive ridley ( Lepidochelys olivacea ), hawksbill ( Eretmochelys imbricata ) and two subpopulations of loggerhead ( Caretta caretta ) turtles...

Ex situ management is an important conservation tool that allows the preservation of biological diversity outside natural habitats while supporting survival in the wild. Captive breeding followed by re‐introduction is a possible approach for endangered species conservation and preservation of genetic variability. The Cayman Turtle Centre Ltd was established in 1968 to market green turtle ( Chelonia mydas ) meat and other produ...

Climate change associated sea‐level rise (SLR) is expected to have profound impacts on coastal areas, affecting many species, including sea turtles which depend on these habitats for egg incubation. Being able to accurately model beach topography using digital terrain models (DTMs) is therefore crucial to project SLR impacts and develop effective conservation strategies. Traditional survey methods are typically low‐cost with l...

Despite concerns regarding the environmental impacts of microplastics, knowledge of the incidence and levels of synthetic particles in large marine vertebrates is lacking. Here, we utilize an optimized enzymatic digestion methodology, previously developed for zooplankton, to explore whether synthetic particles could be isolated from marine turtle ingesta. We report the presence of synthetic particles in every turtle subjected...

Few studies have looked into climate change resilience of populations of wild animals. We use a model higher vertebrate, the green sea turtle, as its life history is fundamentally affected by climatic conditions, including temperature‐dependent sex determination and obligate use of beaches subject to sea level rise ( SLR ). We use empirical data from a globally important population in West Africa to assess resistance to climat...

Somatic growth is an integrated, individual‐based response to environmental conditions, especially in ectotherms. Growth dynamics of large, mobile animals are particularly useful as bio‐indicators of environmental change at regional scales. We assembled growth rate data from throughout the West Atlantic for green turtles, Chelonia mydas , which are long‐lived, highly migratory, primarily herbivorous mega‐consumers that may mig...

Marine turtles are considered keystone consumers in tropical coastal ecosystems and their decline through overexploitation has been implicated in the deterioration of reefs and seagrass pastures in the Caribbean. In the present study, we analysed stomach contents of green ( Chelonia mydas ) and hawksbill turtles ( Eretmochelys imbricata ) harvested in the legal turtle fishery of the Turks and Caicos Islands (Caribbean) during...