Striped Marlin

About the Species

Striped marlin are a highly migratory fish living at the top of the food chain in the tropical and subtropical regions of the Pacific and Indian Oceans. It is a member of a larger family known as billfish, which get their name from their upper jaw that extends to form a spear. Because of their large size, marlin are prized sport fish. Striped marlin also support large commercial fisheries throughout the Pacific Ocean.

Status

• According to the 2010 stock assessment, the Eastern Pacific stock is not overfished and not subject to overfishing. The Inter-American Tropical Tuna Commission (IATTC) conducted this assessment.
• According to the 2015 stock assessment, the Western and Central North Pacific stock is overfished and subject to overfishing. The overfished status of this stock of striped marlin is due to international fishing pressure. Because of this, the stock is not being managed under a rebuilding plan as would be required for purely domestic fish stocks.
• The Western and Central Pacific Fisheries Commission (WCPFC), of which the United States is a member, has agreed to international conservation and management measures for this species. While these current measures may not be sufficient in ending overfishing or rebuilding the stock, NOAA Fisheries continues to work with the Western Pacific and Pacific Fishery Management Councils and the U.S. Department of State to recommend or propose effective management measures to be adopted by the WCPFC.
• Population assessments for the Western and Central North Pacific striped marlin stock are conducted by the Billfish Working Group of the International Scientific Committee for Tuna and Tuna-Like Species in the North Pacific Ocean (ISC). NOAA Fisheries scientists participate in the ISC assessments and contribute relevant U.S. fishery data.

Appearance

• Striped marlin are large, oceanic fish with long, round bills, small teeth, and a tall dorsal fin.
• Their bodies are dark blue-black on the top and fade to a silvery white on the bottom.
• They have rows of blue colored stripes made up of smaller round dots or narrow bands.

Biology

• Striped marlin are smaller than other marlin species, but can reach a length of 12 feet and weigh more than 450 pounds.
• Spawning occurs in the central Pacific and off central Mexico.
• Juvenile fish move east toward the coast of Mexico, where they are found in high abundance around the tip of the Baja Peninsula.
• Striped marlin are opportunistic feeders of fish including mackerel, sardine, and anchovy. They will also eat invertebrates, including squid.
• Off the coast of southern California, they often feed at the surface on small coastal fish and squid.
• Large pelagic sharks or toothed whales prey on adult marlin.

Where They Live

Striped marlin live throughout tropical and sub-tropical waters of the Pacific and Indian Oceans.

Management

• NOAA Fisheries and the Western Pacific Fishery Management Council manage the Pacific striped marlin fishery domestically.
• Managed under the Fishery Ecosystem Plan for Pacific Pelagic Fisheries of the Western Pacific Region:
  • Entry to this fishery is limited to a maximum of 164 vessels.
  • Permits and logbooks are required.
  • Observers are required on all Hawaii-based vessels using longlines.
  • NOAA Fisheries vessel monitoring system program requires longline boats to be equipped with a satellite transponder that provides real-time vessel position updates and tracks vessel movements.
  • Longlines are prohibited in certain areas to protect endangered Hawaiian monk seals and reduce the potential for gear conflicts and localized stock depletion.
  • Vessels operating under longline general permits must carry special gear to release incidentally hooked or entangled sea turtles, marine mammals, and seabirds, and fishermen must attend protected species workshops.
  • Fishing gear requirements apply to all Hawaii longline limited access permitted vessels. The requirements may change depending on type of fishing trip, location of fishing, and how the gear is set. Regulation summaries can be found here.
• NOAA Fisheries and the Pacific Fishery Management Council manage the Pacific striped marlin fishery on the West Coast, in federal waters (3 to 200 miles offshore).
• Managed under the Fishery Management Plan for U.S. West Coast Fisheries for Highly Migratory Species:
  • Striped marlin is included in the plan because of its importance to the recreational (sport) fishery in California.
  • There is no commercial fishery for striped marlin. Sale of striped marlin by vessels under PFMC jurisdiction is prohibited.
• Management of highly migratory species, like Pacific striped marlin, is complicated because the species migrates thousands of miles across international boundaries and are fished by many nations.
• Effective conservation and management of this resource requires international cooperation as well as strong domestic management.
• Two organizations, the Inter-American Tropical Tuna Commission (IATTC) and the Western and Central Pacific Fisheries Commission (WCPFC) manage this fishery internationally.
  • These Commissions rely on the scientific advice of their staff and the analyses of the International Scientific Committee for Tuna and Tuna-like Species in the North Pacific (ISC) to develop and adopt international resolutions for conservation and management measures.
  • Working with the U.S. Department of State, NOAA Fisheries domestically implements conservation and management measures adopted by WCPFC and IATTC.