Cruise Report for the Vaquita Expedition in 2008 Conducted Aboard NOAA Ship David Starr Jordan, R/V Koipai Yu-Xa and the Vaquita Express.

摘要

A small porpoise (Phocoena sinus) found only in the upper Gulf of California is called vaquita and is the most endangered species of marine mammal in the world. A rough projection using the last abundance estimate in 1997 and mortality in gillnets resulted in an estimate of only about 150 vaquitas remaining prior to the 2008 survey. With so few vaquitas remaining, the visual and acoustic methods used to monitor trends in vaquita abundance in the past were too imprecise to determine whether the species is continuing to decline. The primary objective of the cruise was to develop the ability to monitor trends in abundance for vaquitas using acoustic monitoring equipment (autonomous devices and towed hydrophones). Autonomous acoustic devices should increase precision because they can record for long periods of time; however, such devices were yet to be tested in the noisy vaquita habitat.