Integrating Survey-Based Habitat Models into the California Swordfish Fishery Dynamic Management Tool

The risk of bycatch of dolphins and whales in the drift gillnet fishery has resulted in closures and regulatory changes to the swordfish fishery by the Pacific Fishery Management Council. This project will use cetacean sighting data from shipboard surveys to develop models that estimate the probability of cetacean presence given environmental conditions, as well as subsequent potential for bycatch in drift gillnet fishing. Cetaceans will be incorporated into the existing EcoCast bycatch modeling framework that includes other protected species such as leatherback sea turtles, and which includes a mobile application to record and display sightings. The results will provide maps in near real time of where bycatch of multiple species is likely to occur in the future, using both fishery independent and dependent data. Investigators will hold a fishermen’s workshop to discuss potential improvements to the EcoCast app and expand its voluntary use by fishermen. Investigators intend to adapt the resulting models to inform possible changes in commercial fishing gear and potential hard-capped species in the future.