SAVING SEAFOOD RADIO: International Tuna Management Expert Dr. Victor Restrepo Refutes Myth that 90 Percent of Large Predatory Fish Biomass has Disappeared
WASHINGTON, D.C. (Saving Seafood) -– October 31, 2013 -- In this
installment of Saving Seafood Radio, Dr. Victor Restrepo, Senior Vice
President of Science at the International Seafood Sustainability
Foundation (ISSF), discusses new research refuting claims from a
commonly cited study alleging that the world’s oceans have lost more
than 90 percent of their large predatory fish, including tuna. The
conclusive analysis is the work of Dr. Maria José Juan-Jordá, a
researcher who recently completed her Ph.D. at the Universidade da
Coruña in Galicia, Spain. Dr. Restrepo presided over the presentation
and defense of Dr. Juan-Jordá’s dissertation.
By collecting stock assessment results from 26 populations of tuna and tuna-like species from around the world, Dr. Juan-Jordá was able to conduct a thorough analysis of tuna’s global biomass. While some environmental groups have long embraced a statistic indicating that 90 percent of the global biomass of tuna has vanished, Dr. Juan-Jordá’s dissertation concludes that this decline is actually closer to 50 percent, a figure that tuna fisheries scientists, like Dr. Restrepo, have long considered to be a more accurate estimate.
Dr. Restrepo explains that the 90 percent estimate, which first appeared in a 2003 paper by marine scientists Ransom A. Myers and Boris Worm, of Dalhousie University in Nova Scotia, Canada, extrapolated its data from longline fisheries only. What Boris and Worm did not consider was that the type of fishing gear used in these fisheries only targets a certain segment of the population, particularly the larger fish. By failing to account for the complexity of tuna fisheries, Myers and Worm’s inaccurate hypothesis ultimately created a popular myth that affects the way these stocks are managed even today.
November 24, 2014 -- It was certainly good to see the New England Fisheries Management Council vote last week to reject a NOAA move to uniformly and concurrently institute spawning closures in four prime fishing areas that surround Gloucester — and to instead look toward seasonal closures that should at least give Gloucester’s endangered groundfishing fleet some alternatives to stay afloat.