Present Assessment of Possible Environmental Influences
on California Commercial Landings Data
at the 2002 CalCOFI Conference

Current Status of Accomplishment or Milestone: This milestone was completed on 14 November 2002.

Background: Records of the commercial harvest of fish and invertebrates landed in California ports, compiled by State of California Department of Fish and Game from 1928 to 2001, have been converted from printed documents to computer accessible formats at the Pacific Fisheries Environmental Laboratory (PFEL). Previous studies have addressed the fluctuation of certain species over time, but this study is the first to examine 70-year time series of 43 species groups for possible environmental effects on species composition.

Purpose of Activity/Goal of Project: To investigate the effects of environmental variation on the species composition of commercial landings of California ocean fish and invertebrates. If environmental forcing of species availability is proven, then management options will be increased and stakeholder confidence in the regulations will be enhanced.

Description of Accomplishment and Significant Results: The fisheries data-base reveals a change in the relative abundance of certain species in the mid-1970s. This change appears robust and determined by groups of several species. Taking 43 species as a complete system, circumvents some ambiguity in what the data set might represent. Market factors tend to smooth short-term fluctuations, but larger-scale, longer lasting environmental events are clearly evident in relative species catch composition. These preliminary results have been organized into a presentation that was delivered that the 2002 California Cooperative Oceanic Fisheries Investigation (CalCOFI) conference convened at Scripps Institution of Oceanography on 13 and 14 November 2002. The preparation of a report for 2003 CalCOFI publication is now underway.

Significance of Accomplishment (e.g., to the Center, to Management, and to NMFS Strategic plan Goals): It has been shown that environmental signals are pervasive enough to be clearly evident in fluctuations in catch composition, even though the data base in not a precise representation of the California ocean ecosystem. Since this study uses annual data from all California ports, it provides a large-scale, multi-species demonstration of the importance of environmental changes on catch composition and environmental control of species availability.

Problems: Ideally, the data-base would represent an assessment of the relative numbers of each species present in the ocean off California. Unfortunately, there are a number of issues in the way of considering these data from that perspective. The largest problems are in the recording of several species together in catch-groups during the record’s earlier years, leading to inconsistencies in some of the 43 species groups.

Key Contact: Jerry Norton, (831-648-9031, jnorton@pfeg.noaa.gov) or Jan Mason (831-648-9028, jmason@pfeg.noaa.gov).