IMIS

This 1992 line-transect survey was designed to make abundance estimates of the central stock of common dolphin, Delphinus delphis, in the eastern Pacific. This stock of dolphin is taken in the tropical tuna fishery and has suffered a substantial decline. Previous surveys covering larger areas have permitted estimates of abundance, but with low precision. This survey was conducted by the NOAA Southwest Fisheries Science Center aboard NOAA Ships David Starr Jordan and McArthur for a combined total of approximately 32,000 kilometers surveyed from late July to early November 1992. This dataset provides the time-date and geographical coordinates, by species/stock, of all cetaceans detected during the survey, as well as the daily and intra-daily start and end points of the line-transect survey. Purpose The primary purpose of the cruise was to survey the area inhabited by the central stock of common dolphins, and to make an estimate of its absolute abundance in order to assess the impact of the dolphins killed by the United States and international yellowfin tuna purse seine fleet in the eastern tropical Pacific.