Shadowing the tuna boats

Logbooks, satellites, and game theory help steward tuna in the Pacific. 


IN THE National Archives in Boston, stacks of fishing logbooks from the 1880s detail the once abundant catches of cod off the coast of New England. The skippers who kept these logbooks 150 years ago would have been sad if they had known the rest of the story. So in demand that Europeans called it “British gold,” the cod’s mild-flavored flesh sparked a Cod War between Iceland and the United Kingdom in the 1950s. Then trawlers increased catches dramatically, and the fish population crashed by the 1990s. Cod catches in New England are now a measly five percent of what fishermen used to catch in the 1880s.

Today in San Diego, California, logbooks tell a similar story: forty years of skippers’ notes and statistics from the Inter-American Tropical Tuna Commission (IATTC) detail increasing catches and growing fishing efforts in the eastern Pacific Ocean. The IATTC, whose member countries manage fish stocks in the region, imposes an annual quota on how much fish each country is allowed to catch—in hopes of averting a fate similar to the cod.

With three of four major species of tuna in the eastern Pacific Ocean fully exploited, scientists think that better fish forecasts and quotas could save the tuna. Biological oceanographer Dale Kiefer said, “Fishermen use a lot of satellite imagery. We want to catch up with them.” Kiefer and his colleagues have some novel ideas about fusing logbook data with satellite data to keep boats away from younger fish and allow the tuna population to recover.

Story originally published in Sensing Our Planet: NASA Earth Science Research Features. Read the full story here.

Image courtesy T. Ichishima.