Billfish Research

Black marlin (Makaira indica). The billfish researchers at SWFSC provide information for the conservation and rational management of billfish resources in the Pacific Ocean. Species of interest are Pacific blue marlin (Makaira nigricans), striped marlin (Kajikia audax), Indo-Pacific sailfish (Istiophorus platypterus), black marlin (Makaira indica), shortbill spearfish (Tetrapturus angustirostris), and broadbill swordfish (Xiphias gladius). Program staff are committed to providing sound fishery data analysis, fishery management information, and advice for U.S. fishery management councils and international agencies. 







 Attention anglers!

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Cooperative Billfish Tagging Program and International Billfish Angler Survey- The SWFSC administers the Cooperative Billfish Tagging Program and International Billfish Angler Survey, and since 1969, tagging materials have been provided to recreational billfish anglers around the world. The goal of this program is to provide information for the conservation and rational management of the billfish resources in the Pacific. Participation from recreational anglers, sportfishing clubs, commercial fishers, and agencies affiliated with the SWFSC provide the basis for locality specific catch-per-unit-effort (CPUE) data, creating over 50 years worth of time-series data available for these gamefish. The program receives tagging and angler information from locations across the Pacific on billfish such as blue marlin (Makaira nigricans), striped marlin (Kajikia audax), and sailfish (Istiophorus platypterus). Information on the distribution, migration patterns, and growth rate of billfish throughout the Pacific are also published in the Billfish Newsletter as an outreach program.  


Bycatch reduction in swordfish fisheries- Swordfish are the second most important HMS targeted in commercial fisheries off the U.S. West Coast. In recent years, swordfishing effort has declined dramatically due to regulations put in place to reduce bycatch of protected species including leatherback sea turtles. In an initiative called the Swordfish and Leatherback Use of Temperate Habitat (SLUTH), FRD is collaborating with SWFSC’s Marine Mammal and Turtle Division (MMTD) to reduce bycatch of leatherback turtles by developing a better understanding of habitat use for both species and subsequently increasing fishing selectivity. The hope is to capitalize on differences in habitat used during the day when swordfish move into deep water and leatherbacks remain shallow. In an ongoing study with the Pfleger Institute of Environmental Research The previous link is a link to Non-Federal government web site. Click to review NOAA Fisheries Disclaimer (PIER), pop-off satellite archival tags are deployed on swordfish to characterize daytime depths and habitat use. 


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Last modified: 7/22/2016