Evaluation of a Marine Mammal Excluder Device (MMED) for a Nordic 264 Midwater Rope Trawl

摘要

The Southwest Fisheries Science Centers (SWFSC) La Jolla Laboratory of the National Marine Fisheries Service (NMFS) uses a Nordic 264 pelagic rope trawl from Northeastern Trawl Systems (NETS) in Seattle to sample adult coastal pelagic fish species during cruises along the U.S. west coast. The primary objective of these cruises is to measure population dynamics of Pacific sardine (Sardinops sagax) in order to set management goals for the coastwide U.S. fishery. The Nordic 264 is also used in salmon (Oncorhychus spp.) research by the SWFSC Santa Cruz lab, the Northwest Fisheries Science Center (NWFSC) Newport lab, and the Alaska Fisheries Science Center (AFSC) Auke Bay Laboratories. Issues of bycatch (capture of non-targeted species) are always present, particularly possible encounters with marine mammals (pinnipeds and cetaceans). To reduce any possible marine mammal bycatch during scientific sampling surveys a marine mammal excluder device (MMED) was designed, built and installed in two of the SWFSC Nordic 264 nets and tested during the 2009 field season. The purpose of this project was to develop and test a MMED for use in the Nordic 264 mid-water trawl used by several NMFS agencies in the course of fisheries research.