Management of Tropical Tunas in the Eastern Pacific Ocean

Abstract

Abstract Yellowfin tuna (Thunnus albacares) and skipjack tuna (Katsuwonus pelamis) are harvested in the eastern Pacific Ocean by the fishing fleets of 10 nations. From 1950 to 1960 the combined catches of these two species averaged about 310 million pounds per year. With the advent of newly designed and highly efficient purse seine gear in the early 1960's the catches increased, on the average, by about 10 to 20%. Much of this increase was in yellowfin tuna. Studies by the Inter-American Tropical Tuna Commission have shown that this increased production reduced the population of yellowfin slightly below the size at which biomass production is maximal but has not affected the abundance of skipjack. On recommendations of the Commission, international agreement was reached in 1966 to restrict the capture of yellowfin tuna by a general quota system. A management program has been in effect since that time, and has resulted in the restoration and maintenance of the stock of yellowfin tuna at a level that can su...