Index of visual monitoring, location, species behavior, and identification from CalCOFI cruises in the California Current System, 2008 - 2009. This dataset has been superseded by knb-lter-cce.262.

Visual monitoring efforts for cetaceans has been conducted on quarterly CalCOFI cruises since July 2004. This effort utilizes a standard line-transect protocol (Burnham et al. 1980;Buckland et al. 1993; Barlow 1995). Visual observers watch during daylight hours, when weather permits (Beaufort sea states 0 to 5 and visibility greater than 1 nautical mile) and while the ship transits between CalCOFI stations. A team of two observers search for cetaceans in a 90 degree field of view from the bow to beam of the ship, alternating between 18 and 50 power binoculars and the naked eye.