Navigating danger: Watercraft-related mortality of sea turtles in the United States Atlantic and Gulf coastal waters

Abstract

Sea turtles and watercraft often share waters, placing turtles at risk of being injured or killed by vessel strikes. Although watercraft injuries are a known threat to multiple species of imperiled sea turtles, previous studies of their impact are spatially limited. This is the case in the western Atlantic and Gulf waters of the USA, where four protected species of sea turtles regularly nest and forage: the loggerhead (Caretta caretta), green (Chelonia mydas), Kemp's ridley (Lepidochelys kempii), and leatherback (Dermochelys coriacea) turtles. To better inform management and conservation of sea turtles in the region, we characterize the spatiotemporal trends in stranded sea turtles with vessel strike injuries (VSI) from 2010 to 2022 and identify significant clusters of stranded turtles with these injuries. Frequency of VSI is considerable, with such injuries documented in a quarter of all stranded turtles. Most of the turtles found with VSI were green turtles and loggerheads, mainly found in Florida and Texas, with significant clusters of strandings with VSI found across our study region. Kemp's ridleys with VSI were predominantly found in Florida, Mississippi and Texas, and most vessel-struck leatherbacks stranded in Massachusetts. Spatiotemporal trends in strandings with VSI were characterized for each sea turtle species, which can inform efforts to prioritize areas for future studies and conservation efforts.