AFSC/NMML: Shore-based counts of the Eastern North Pacific gray whale stock from central California, 1967 - 2007

The National Marine Fisheries Service (NMFS) has conducted shore-based counts of the Eastern North Pacific stock of gray whales (Eschrichtius robustus) 26 years from 1967 to 2008 at Granite Canyon (or nearby at Yankee Point), 13 km south of Carmel, in central California. Convenient access to the Granite Canyon research station (owned by NOAA but operated by the State of California Department of Fish and Game) and the narrowness of the whales' migratory corridor in this area permitted an efficient counting process at this site. All counts were conducted during the 2-month southbound migration (mid-December to late February) rather than the protracted 3-month northbound migration. The routine nature of these counts and the consistency in research protocol lend themselves to inter-annual trend analyses. Research protocol has been based on single observers independently searching for whales and recording data on environmental conditions and the time, location, count, and direction of travel for each sighting. The counting system and observer performance has been tested through paired, independent observational effort; aerial surveys; thermal imagery; radio-tagging of whales; systematic observations through high-powered (25x) binoculars; and teams of observers tracking specific whale pods through the viewing area.