학술논문
Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008
Document Type
article
Author
Source
Fishery Bulletin. 112(2-3)
Subject
Language
Abstract
Documenting year-round diversity and distribution of marine mammals off Southern California is important for assessment of effects of potentially harmful anthropogenic activities. Although the waters off Southern California have been surveyed extensively for marine mammals over the past 18 years, such surveys have been periodic and were conducted primarily from summer to fall, thereby missing potential seasonal shifts. We examined seasonal abundance and population density of cetaceans off Southern California from 16 shipboard line-transect surveys conducted quarterly during 2004-08. The study area consisted of 238,494 km2 of coastal, shelf, and pelagic oceanic habitat from nearshore waters to 700 km offshore. Based on 693 encounters of 20 cetacean species, abundance estimates by seasonal period (summer-fall or winter-spring) and depth (shallow: