Summary
Acoustic alarms reduce bycatch of harbor porpoises (Phocoena phocoena) in the Gulf of Maine sink gillnet fishery. Gillnets with and without acoustic alarms caught similar quantities of target species, cod and pollock. Acoustic alarms did not affect catch of bycaught silver hake, but Atlantic herring was caught less frequently in experimental nets with alarms. Harbour seals depredated fish caught in both nets with and without acoustic alarms.