Abstract

(…) In the autumn of 2008, a large-scale international effort to study the vaquita and develop methods to monitor its population status was conducted. As part of this effort, we investigated the feasibility of getting high-quality photos of vaquitas and of using photo-identification methods. From 2-30 October 2008, we conducted small-vessel surveys for vaquitas from a shore-based station in San Felipe, Baja California Norte, Mexico. Each day, weather permitting, we traveled offshore to the region where past vaquita sightings had been concentrated (between San Felipe and Rocas Consag, a small island about 30 km offshore- Jaramillo-Legorreta et al., 2007).). We searched for vaquitas while the vessel was moving, but also periodically conducted ‘stop and drift’ searches, in which the vessel’s engine and depth sounder were shut down, and 3-6 observers searched the area with naked eye and binoculars. (…)