Marine Mammal Data Collected during a Survey in the Eastern Tropical PacificOcean Aboard the NOAA Ships McARTHUR and DAVID STARR JORDAN, July 28-December 9, 1999

摘要

This report summarizes the survey procedures and data obtained for marine mammalsin the eastern tropical Pacific Ocean (ETP) in 1999 during the Stenella Abundance Research (STAR99) project. This was the second year of a three-year (1998-2000) multidisciplinary study conducted by the National Marine Fisheries Service, Southwest Fisheries Science Center (SWFSC) on the ETP dolphin ecosystem. Separate reports will summarize the associated fauna (Olson et al., in prep) and the environmental and oceanographic findings (Philbrick et al., in prep). The project's first year of data obtained in 1998 for marine mammals was summarized in Kinzey et al. (1999). In 1997 the U.S. Congress directed the Secretary of Commerce to determine whether the chasing and deployment of purse seine nets around dolphins during tuna fishing operations is having a significant adverse impact on any depleted dolphin stock (International Dolphin Program Conservation Act, Public Law 105-42). A portion of this mandate directed the National Marine Fisheries Service to undertake a series of surveys between 1998 and 2000 to estimate the current abundances of the populations of dolphins in the area affected by the fishery. At a planning meeting in December 1997 (Gerrodette et al., 1998), survey procedures and boundaries for the study area were discussed. The results of the 1998 survey were used to estimate the 1998 abundances of four target stocks of dolphins (Gerrodette, 1999). Estimates of the 1999 abundances of cetacean stocks in the ETP will be based on the sightings described in this report.