SS1.06 The Ecological Impacts of Pelagic Longline Fisheries
Date: Monday, June 10, 2002
Time: 11:45:00 AM
Location: Carson A
 
D'AgrosaCE, Duke University Marine Lab, Beaufort, USA, ced@duke.edu
Hyrenbach, K, D, Duke University Marine Lab, Beaufort, USA, khyrenba@earthlink.net
Rilov, G, , Duke University Marine Lab, Beaufort, USA, gr3@duke.edu
Crowder, L, B, Duke University Marine Lab, Beaufort, USA, lcrowder@duke.edu
 
SEA TURTLE BYCATCH IN U.S. PELAGIC LONGLINE FISHERIES: THE SIGNIFICANCE OF OCEANIC HABITATS AND FISHING PRACTICES
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In addition to catching tuna and swordfish, pelagic longlines take many non-target taxa, including highly-endangered leatherback turtles (Dermochelys coriacea) and loggerhead turtles (Caretta caretta). We examine the spatial and temporal patterns of fishing effort and sea turtle bycatch documented by observers in the U.S. North Atlantic (1992-1999) and Hawaiian-based (1994-2000) pelagic longline fisheries. We determined that fishing effort and bycatch were significantly associated with specific static (e.g., bathymetric) and dynamic (e.g., hydrographic) habitats. Moreover, there are disparities in turtle susceptibility to different fishing practices. Of the 166 observed loggerhead turtle takes in the Hawaiian fishery, 100% occurred in sets targeting swordfish. Similarly, over 90% of the 340 observed loggerhead turtles hooked in the North Atlantic fishery were taken in swordfish and mixed sets. Leatherback turtles were also disproportionately taken (75%) in swordfish and mixed sets in both fisheries. Because marine turtles do not concentrate exclusively along restricted bathymetric habitats (e.g., shelf-slope regions), our results suggest that traditional 'site-specific' management approaches (e.g., MPAs, time-area closures) may only provide limited protection for these broadly-distributed species.