Chapter 9 preface: Tuna stocks are decreasing

The Eastern stock of the Atlantic bluefin tuna has declined precipitously in the last 10 years. Based on estimated catches, scientists estimated the spawning stock biomass in 2007 to be 78,724 tons. This contrasts with the biomass peak estimated for 1958 at 305,136 tons. The decline over the 50-year historical period ranging from 1957 to 2007 is estimated at 74.2%, the bulk of which (60.9%) was in the last 10 years. Threats to the eastern stock include overharvesting and illegal, unregulated, and unreported (IUU) fishing by European and Mediterranean fishing fleets. The Western Atlantic spawning stock has declined by 82.4% from 49,482 tons in 1970 to 8,693 tons in 2007. In the past, decade, the Western stock has stabilized at a very low population level. Many experts correlate this stabilization to stronger management and compliance measures adopted for that stock, including scientifically based harvest quotas and a catch documentation scheme to ensure rigorous compliance by United States fishers.

Source: Department of the Interior News Release October 14,2009