Estimated bycatch of marine mammals and sea turtles in the U.S. Atlantic pelagic longline fleet during 2014

• Main Authors: Garrison, Lance P., Stokes, Lesley
• Format: Text
• Language: English
• Published: U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center 2016
• Subjects: Longlining Fisheries > Bycatches > -Atlantic Coast South Atlantic States > -Statistics.; North Atlantic
• Online Access: https://dx.doi.org/10.7289/v5/tm-sefsc-696; https://repository.library.noaa.gov/view/noaa/14390

The U.S. Atlantic Pelagic Longline fleet operates throughout the northwestern Atlantic Ocean, including along the U.S. coast from the Gulf of Mexico to New England, the waters of the Caribbean, and in international waters of the North Atlantic Ocean. The Atlantic longline fleet is defined as a Category I fishery under the Marine Mammal Protection Act, and it is also the subject of management under the Endangered Species Act due to interactions with leatherback (Dermochelys coriacea) and loggerhead (Caretta caretta) turtles. Total bycatch of marine mammals and turtles in the longline fishery was estimated for 2014 using data from the pelagic longline fishery observer program and a mandatory fishery logbook reporting program. We applied a delta-lognormal approach to estimate region specific and total annual interactions with protected species in the fishery. During 2014, there were an estimated 281.0 (200.3 -- 394.9 [95% CI]) interactions with leatherback turtles and 260.9 (167.3 -- 407.6 [95% CI]) interactions with loggerhead turtles. In addition, there were an estimated 6.2 (1.6 -- 23.7 [95% CI])interactions with Olive Ridley turtles. The primary marine mammals interacting with this fishery were pilot whales (Globicephala sp.) in Western North Atlantic waters. Interactions were apportioned between short-finned and long-finned pilot whales based upon location and environmental parameters. The majority of interactions were with short-finned pilot whales with an estimated 233.4 (145.9 -- 73.2 [95% CI]) interactions resulting in serious injury and an additional 40.4 (15.8 -- 103.4 [95% CI]) interactions in which the animal was released alive. Potential sources of bias and uncertainty in these bycatch estimates are discussed.