Examination of Variability in California Commercial Fish Data Base (CACom)

Current Status of Accomplishment or Milestone: Because this study has begun to yield results that may be used in aiding management decisions, it is ongoing.

Background: California State laws require that all sales of fish and invertebrates from primary harvesters (fishers) to fish dealers be recorded and the species (or species groups) and weight landed be recorded on the sales receipts. These sales receipts, tabulated by the Department of Fish and Game, and complementary data were put into Internet accessible form (PFEL's LAS) by the Pacific Fisheries Environmental Laboratory.

Purpose of Activity/Goal of Project: The CACom data may provide opportunities to separate climate-scale environmental factors from economic factors in the variability of commercial fish landings. Because climate-scale changes persist over decades, prediction based on persistence maybe possible. The goal of the investigation is to find if the landings records provide information that will facilitate ecosystem management decisions.

Description of Accomplishment and Significant Results: We have described two modes of variation in the landings data that appear to reflect physical climate effects. These results have been reported at California Cooperative Oceanic Fisheries Investigation (CalCOFI) meetings in 2002, 2003 and 2004 and in three papers in CalCOFI Reports, volumes 44 and 45. Reports have also been given at Pacific Climate Workshops and published in the proceedings volumes of those workshops. The most recent presentation was given at a Sardine Fishery Workshop Symposium sponsored by CalCOFI in La Jolla, California. In that presentation, we showed that the fluctuations in sardine catch during the 1930-2000 period were related to their abundance and to changes in their physical and biological environment.

Significance of Accomplishment (e.g., to the Center, to Management, and to NMFS Strategic plan Goals): If these results continue to be confirmed, it will allow management decisions to be based on knowledge of probable future fluctuations in the resources. The fisheries for west coast sardines have a 500,000 tons per year potential. Sardine fisheries are presently reforming in California, Oregon and Washington under regulations provided by the Pacific Fishery Management Council (PFMC). The results of our studies may be useful to the PFMC process of establishing longer-term policy concerning quotas and capitalization in U.S. sardine fisheries.

Problems: Problems arise when dealing with decadal and longer scales, because there may be only one, two or partial occurrence of the cycles detected. This means that non-causal coincidence cannot be ruled out by statistical means. However, observations that similar cycles are found in a variety of fish-components of the California Current ecosystem and in basin-wide environmental indices suggest that mechanistic links between the physical and biological environments have been detected.

Key Contact: Jerry Norton (831-648-9031, jerrold.g.norton@noaa.gov)