Assessing and mitigating the impacts of bycatch mortality of endangered loggerhead turtles, Baja California Sur

Natalia Rossi

The critically endangered North Pacific loggerhead turtle (Caretta caretta) nests exclusively in Japan, and juveniles undertake developmental migrations that can last several decades and span the entire Pacific. Juvenile loggerheads aggregate in the rich waters of Baja California Sur, Mexico (BCS), apparently to forage their way to maturity and to fuel their return migration to Japan, where they are thought to remain through adulthood. Because hundreds of loggerheads are accidentally killed in small-scale fisheries along the BCS coast annually, it is essential to verify key life history traits of the BCS foraging population to evaluate the demographic effects of this bycatch mortality. The project encompasses four main goals, which are: i) assessing the reproductive status and sex ratio of individuals caught and stranded at BCS ii) estimating age and growth through skeletochronological analysis and iii) developing a health assessment of the North Pacific loggerhead population and, iv) engaging the local fishermen in the research and conservation efforts.