Historical Catch Data From California's Commercial Passenger Fishing Vessel Fleet: Status and Comparison of Two Sources

摘要

Two sources of historical landing data from California's commercial passenger fishing vessel (CPFV) fleet were examined to: 1) assess status and content of each archival data source, 2) identify reporting differences, and 3) evaluate potential usefulness of the data for enhancingudresource assessment. Current and historical CPFV logbook data collected by California Department of Fish and Game are described with respect to status, content, and approximate cost of recovering historical data (1936-78) to electronic format. CPFV landing data available from Los Angeles Times, archived in libraries since 1959, are similarly described.udCPFV logbook data were compared with observer data from 1985-89 to evaluate accuracy of logbook records. Comparison of catch and effort for major species targeted by southern California CPFV anglers revealed significant relationships between reported and observed catch rates for six of ten species examined. Agreement of catch rate trends validates use of logbook data for measuring relative changes in catch and effort for these sport fish species. udDirect comparisons of landings data from CPFV logs and Los Angeles Times fish reports were made for years in which Times data are already available in electronic database format, including 1959, 1967, 1975, 1983, 1991, and 1992. Comparisons of total landings by species among years revealed strong correlations between the two sources for those species (e.g., California barracuda, yellowtail, bonito) most heavily targeted over the entire period. Otherudspecies, such as California sheephead, spotted scorpionfish, and ocean whitefish, were underreported or not reported by the Times until recently. Comparison of port-wide total landings of all species (1983, 1991, 1992) revealed varied reports of total catch (all species) between sources among ports and years. Times-logbook landing report comparisons were highly correlated for Los Angeles area ports (r2=0.956), but were also most different in absolute number, with Times reports being an average of 48% higher than logbook totals. Comparison of species landings by port in 1992 revealed additional port-wide differences in reporting between both sources.udHistorical CPFV logbook records have higher spatial resolution (catch location as opposed to port of landing), span a greater period, and will be cheaper to recover into electronic database format than Times fish reports. Historical Times data have higher temporal resolution (daily v. monthly), but II cost approximately $165,000 to recover as opposed to $11 ,000 for logbook data summaries covering a longer period. Strong correlation between the two sources shows usefulness of Times data for tracking real-time changes in sport catch in southern California. (53pp.)