Marine species mortality in derelict fishing nets in Puget Sound, WA and the cost/benefits of derelict net removal.
Derelict fishing gear persists for decades and impacts marine species and underwater habitats. Agencies and organizations are removing significant amounts of derelict gear from marine waters in the United States. Using data collected from repeated survey dives on derelict gillnets in Puget Sound, Washington, we estimated the daily catch rate of a given derelict gillnet, and developed a model to predict expected total mortality caused by a given net based on entanglement data collected upon its removal. We also generated a cost:benefit ratio for derelict gear removal utilizing known true costs compared to known market values of the resources benefiting from derelict gear removal. For one study net, we calculated 4368 crab entangled during the impact lifetime of the net, at a loss of 19,656 dollars of Dungeness crab to the commercial fishery, compared to 1358 dollars in costs to remove a given gillnet, yielding a cost:benefit ratio of 1:14.5.
Gilardi
Kirsten V K
KV
SeaDoc Society, Wildlife Health Center, UC Davis School of Veterinary Medicine, 1 Shields Ave., Davis, CA 95616, United States. kvgilardi@ucdavis.edu
Carlson-Bremer
Daphne
D
June
Jeffrey A
JA
Antonelis
Kyle
K
Broadhurst
Ginny
G
Cowan
Tom
T
D000818:Animals; D018533:Biomass; D001717:Birds; D003386:Brachyura; D003362:Cost-Benefit Analysis; D005398:Fisheries / Q000191:economics* / Q000295:instrumentation / Q000706:statistics & numerical data; D005399:Fishes; D008962:Models, Theoretical; D009026:Mortality; D010140:Pacific Ocean; D014861:Washington; D014876:Water Pollution / Q000191:economics* / Q000706:statistics & numerical data