Summary
This study quantifies fisheries interactions affecting small cetaceans along the Southern Brazilian coast and estimate cryptic mortality masked by decomposition. Researchers analyzed data from 321 necropsied cetaceans collected by the Santos Basin Beach Monitoring Project from 2016 to 2019, focusing on the Franciscana dolphin (Pontoporia blainvillei) and the common bottlenose dolphin (Tursiops truncatus). A high fisheries interaction rate (68%) was observed among 25 well-preserved carcasses. Extrapolating this interaction rate to decomposed P. blainvillei carcasses increased the estimated number of bycaught individuals from 68 to 182, indicating that mortality may be severely underreported.