Towards reducing the data gap in the conservation efforts for sea turtles in Bangladesh

Abstract Despite having 3 of the 11 most endangered Regional Management Units (RMUs) of sea turtles globally, the Bay of Bengal in the South of Bangladesh is undergoing construction of a regional marine road network and tourism infrastructure to boost connectivity and stimulate the economy. Policy makers in developing countries like Bangladesh often face difficulty in prioritizing conservation efforts due to lack of reliable data. In the case of the endangered sea turtles, there is a gap in sea turtle nesting and hatchling data inventory. Therefore, this study presents a comprehensive dataset of all recorded sea turtle nesting, hatchlings, death and habitats, derived by reviewing past literature of Bangladesh. This led to identifying the environmental features that influence turtle nesting behavior based on field surveys. Our results suggest that sea turtles prefer nesting on elevated, broader beaches which are closer to vegetation and away from anthropogenic structures. The beach profile survey shows that more than half of the beaches suffer from anthropogenic disturbances. Satellite image analysis of the study area over the past 30 years revealed a declining trend of beach area after 2008. The beach area has been reduced from 19.44 km2 (1989) to 14.92 km2 (2018) eventually leading to beach width depletion. The results derived from this study can contribute in identifying the most degraded beaches where ecosystem restoration is urgent, as well as, recommending coastal specific policies and guidelines for protecting endangered sea turtle populations.