Analysis of a long-term dataset of Antillean manatee strandings in Belize: implications for conservation

We analysed 23 years of data on strandings of the Antillean manatee Trichechus manatus manatus in Belize, documented by the Belize Marine Mammal Stranding Network, to examine the threats to this population. A total of 451 stranding incidents were reported, of which 376 (83.4%) cases were verified. A total of 286 (63.4%) of the incidents occurred within Belize District, where the number of strandings has almost tripled since 2009. Watercraft collisions accounted for the highest number of strandings, with 131 confirmed cases, and is the leading cause of anthropogenic mortality for this population. Collision with watercraft is an emerging and major threat to manatees in Belize, and is correlated with increases in human activity, in particular associated with tourism. This finding of high levels of manatee deaths in Belize is consistent with trends previously reported for manatees in Florida and Puerto Rico. This work can provide guidance to detect and address similar patterns of mortality in other Antillean manatee populations across the species' range. There is a need for greater awareness of the threats facing the species and its habitat, for stakeholder partnerships to address these threats, implementation of legislation for the protection of manatees, and consistent enforcement of regulations to protect this population. Boating regulations, such as no-wake zones within areas of high manatee presence, as well as regulation of tourism boating activities, need to be implemented to reduce the threats to the species.