Research on Humpback and Blue Whales off California, Oregon and Washington in 2000

Abstract

Abstract : Surveys were conducted in 2000 to continue long-term research studies of humpback and blue whales off California, Oregon, and Washington. Primary objectives of this work include examining the abundance and trends of these two species, movement and migration patterns, and reproduction and mortality rates. This research has also been conducted in association with studies on gray whales and incidental observations of other large whales. Although photographic identification was the primary method used, we also collected skin and fecal samples, made behavioral observations, measured sizes of whales, and deployed an underwater video/instrument package (Crittercam) on blue whales. Support for different aspects of this research in 2000 came from Southwest Fisheries Science Center, Olympic Coast National Marine Sanctuary, Office of Naval Research, Scripps Institute of Oceanography, National Marine Mammal Laboratory, and several individual contributors. Photographic identification studies of humpback and blue whales were conducted off California, Oregon, and Washington April to December 2000. Dedicated surveys were conducted using Cascadia's 5.3m RHIBs and on a few occasions other boats. Collaborating researchers and work from opportunistic platforms provided additional effort and identification photographs especially in Monterey Bay. Identification photographs were taken using standard procedures employed in past research (Calambokidis et al. 1990a, 1990b, 2000a). Both sides of blue whales in the vicinity of the dorsal fin were photographed as well as the ventral surface of the flukes. For humpback whales, photographs were taken of the ventral surface of the flukes. Dedicated and opportunistic effort results in 646 identifications of 254 unique humpback whales. Photographic identification of blue whales conducted in 2000 yielded 335 identifications of 168 unique individuals. Locations of sightings in 2000 were more clumped than in past years.