January 10, 2012
Nanaimo, British Columbia
Chairperson: Sean MacConnachie
The Pacific sardine (Sardinops sagax) is a pelagic schooling fish that is found in British Columbia (B.C.) waters, and when abundant, occupies coastal waters from Baja California to southeast Alaska. In winter and spring months, most of the sardine population resides in waters off the California coast during peak spawning periods. Prior to and during summer months, large aggregations of sardine migrate from key spawning habitat and migrate to more northern waters mainly to forage, but migratory patterns can be affected by population size and oceanographic conditions.
Data from commercial sardine catches and summer research trawl surveys have been used to estimate sardine biomass and migration rates in relation to providing harvest advice (DFO 1999, 2001, 2009, 2011). Scientists in the United States (U.S.) conduct coastwide annual assessments of the population's abundance, recruitment, age and length compositions, based on integrating data from research surveys and commercial catches primarily conducted in U.S. waters, although catch and length data from Canadian sources are also included (e.g. Hill et al 2010).
The most recent framework for setting annual allowable catch of Pacific sardine in B.C. waters results from Regional Advisory Processes conducted in 1999, 2001, and 2009. The framework is based on the product of three factors: 1) the current coastwide sardine biomass estimate resulting from the assessment conducted by U.S. analysts; 2) the U.S. annual harvest rate (DFO 2001; Schweigert and McFarlane 2001), which has been 15% in recent years, but is a function of sea surface temperature and U.S. harvest control rules; and, 3) the application of an estimated rolling average seasonal migration rate of sardine to B.C. waters (DFO 2009; DFO 2011). Rolling average seasonal migration rate estimates have been based on regional sardine biomass estimates in B.C. waters divided by corresponding estimates of the coastwide population biomass. Estimates of sardine biomass in B.C. have been based primarily on data from DFO west coast of Vancouver Island surveys and, beginning in 2011, have included inshore biomass estimates derived from extrapolating mean sardine research trawl catch densities from west coast of Vancouver Island surveys to spatial estimates of inshore areas where sardine has been commercially harvested (DFO 2011; Flostrand et al in press).
Fisheries Management has requested updated information on seasonal sardine biomass and migration into B.C. waters and advice applicable to the current harvest management framework. Because the assessment method was recently reviewed (DFO 2011), updated estimates and corresponding harvest advice will be provided to Regional Advisory Process participants for review in the form of a draft Canadian Science Advisory Secretariat (CSAS) Science Advisory Report.
Pacific sardine 2011 seasonal abundance and migration in British Columbia and harvest advice for 2012
DFO. 2009. Proceedings of the Pacific Scientific Advice Review Committee (PSARC) meeting for the assessment of scientific information to estimate Pacific sardine seasonal migration into Canadian waters. DFO. Can Sci. Advis. Sec. Proceed. Ser. 2009/034
Hill, K.T., Lo, N.C.H., Macewicz, B.J., Crone P.R. and Felix-Uraga, R. 2010. Assessment of the Pacific sardine resource in 2010 for U.S. management in 2011. Pacific Fishery Management Council, Nov 2010 Briefing Book, Agenda Item I.2.b. Attachment 2. 128 p.
Flostrand, L., Schweigert, J., Detering, J., Boldt, J., and MacConnachie, S. 2011. Evaluation of Pacific sardine (Sardinops sagax) stock assessment and harvest guidelines in British Columbia. DFO. Can Sci. Advis. Sec. Res. Doc. 2011/096.
Participation to CSAS peer review meetings is by invitation only.