GLOBEC Northeast Pacific Analyses: Linkages Between Cetaceans and Oceanographic Features
Abstract
Associations between cetacean distributions, oceanographic features and bioacoustic backscatter were examined during two process cmises in the northern California Current System (CCS) during late spring and summer 2000. Line-transect surveys of cetaceans were conducted across the shelf and slope, from Newport, Oregon to Crescent City, California, in conjunction with surveys of ocean and ecosystem structure. Occurrence patterns (presencelabsence) of 4 cetacean species were compared with hydrographic and ecological variables (e.g., sea surface salinity, SST, thermocline depth, halocline depth, chlorophyll maximum, distance to the center of the equatorward jet, distance to the upwelling front, and acoustic backscatter at 38, 120, 200 and 420 kHz). Using a multiple logistic regression model, 60.2% and 94.4% of the variation in occurrence pallems of humpback whales during spring and summer, respectively, were explained. For harbor porpoise, the model explained 79.2% and 70.1% of the variation in their occurrence pattems during June and Auqust, respectively. The responses of cetaceans to upwellinq processes were seasonally and spatially specific.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 22, 2004
- Accession Number
- ADA428487
Entities
People
- Cynthia T. Tynan
Organizations
- Woods Hole Oceanographic Institution