California Cooperative Oceanic Fisheries Investigations (CalCOFI)

In 1949, the California Cooperative Oceanic Fisheries Investigations (CalCOFI) was formed to study the ecological aspects of the collapse of the sardine populations off California. The cooperative is a partnership of the California Department of Fish and Game, the NOAA Fisheries Service and the Scripps Institution of Oceanography. Over time, the focus of CalCOFI has shifted to the study of the marine environment off the coast of California and the management of its living resources.

To this end, CalCOFI conducts quarterly cruises offshore of southern California collecting a suite of hydrographic and biological data at 66 core and 9 coastal stations. Data collected at depths down to 500 m include: temperature, salinity, oxygen, phosphate, silicate, nitrate and nitrite, chlorophyll, C14 primary productivity, phytoplankton biodiversity, zooplankton biomass, and zooplankton biodiversity. Ancillary data collected include bio-optics, air-sea interface, and atmospheric measurements, continuous underway sea surface measurements (temperature, salinity, fluorescence); Acoustic Doppler Current Profiler (ADCP) data; trace metals; sediments; MOCNESS net sampling; and the Continuous Underway Fish Egg Sampler (CUFES). Sea bird visual surveys are conducted during transits between stations. Recently, the CCE-LTER project has expanded CalCOFI goals and added additional sampling including seasonal process cruises and autonomous gliders along lines 83 and 90 (see maps).
In April 2004, our lab added a visual and acoustic marine mammal survey component to the CalCOFI project to study cetacean ecology and habitat. Visual monitoring is conducted during quarterly cruises by experienced marine mammal observers using handheld 7x binoculars. Supplementary Bigeyes (25x) or image stabilizer hand-held binoculars (18x) are used for species identification when necessary. Visual monitoring provides excellent data for highly visible species in calm to moderate weather. Concurrently, acoustic technicians survey with a towed hydrophone array during the transit between CalCOFI stations and with sonobuoys while on station, allowing collection of distribution data on vocal animals that may have been missed visually due to darkness, rough weather, distance from transect line, being underwater, or other reasons. Additionally, long-term acoustic monitoring is conducted at seven CalCOFI stations using bottom-mounted, HARPs. These data will provide information on the annual and seasonal presence of cetaceans, and may be used to evaluate daily patterns of vocalization behavior. By integrating CalCOFI environmental and cetacean data, we plan to develop ecological models for cetacean habitat in the region offshore of southern California and to improve our understanding of their role in the California Current ecosystem.
The most commonly sighted species on visual surveys conducted between July 2004 and November 2005 were blue, fin, humpback, and sperm whales, and Pacific white-sided, short-beaked common, and long-beaked common dolphins. Blue, fin, and sperm whales were sighted more frequently in summer to fall months, while northern right whale dolphins and Dall’s porpoises were sighted more frequently in winter and spring. Spatial patterns of occurrence are evident for all species within the study area.