A description of the tuna-porpoise observer data collected by the U.S. National Marine Fisheries Service from 1971 to 1990

"From 1971 to 1995, the U.S. National Marine Fisheries Service's (NMFS) Tuna- Porpoise Observer Program collected data on the mortality, life history, distribution and abundance of dolphins (colloquially referred to as 'porpoise') associated with yellowfin tuna (Thunnus albacares) in the eastern tropical Pacific Ocean (ETP) and their involvement in fishery operations. This program, which became mandatory for the U.S. fleet in 1976 under the Marine Mammal Protection Act, placed biological technicians ('observers') aboard commercial U.S. purse seiners holding certificates of inclusion under a general permit to take (chase and/or set nets on) certain species of dolphins within the 'permit area' (that area of the Pacific Ocean bounded by 40°N latitude, 40°S latitude, 160°W longitude and the coastlines of the Americas). The ETP yellowfin tuna purse seine fishery exploits the tuna-dolphin association by netting the highly visible, surface-swimming dolphins in an attempt to catch the tuna schooling below them. Dolphins may be killed in the purse seines before they can be separated from the tuna and returned to the open ocean. Most frequently killed in this fishery are dolphins of the genus Stenella and, to a lesser extent, the genus Delphinus. The purpose of this paper is to describe the data collected under Tuna-Porpoise Observer Program from 1971-1990 and archived by the Southwest Fisheries Science Center's (SWFSC) Protected Resources Division (PRD)"--Introduction. Alan R. Jackson. "November 2012." System requirements: Adobe Acrobat Reader. Includes bibliographical references (pages 9-10) and footnotes.