Stock assessments for British Columbia herring in 1985 and forecasts of the potential catch in 1986 / by V. Haist, J.F. Schweigert and M. Stocker. : Fs97-4/1889E-PDF

"Herring stock abundance in British Columbia waters was assessed for 1985, and forecasts were made for 1986 using two methods: (1) escapement method, and (2) age-structured model analysis. The abundance of spawners in the 1985 herring run in British Columbia waters as assessed by the escapement method was 112,000 tonnes. The 1986 run is forecast at 143,000 t with average (1970-85) productivity. The 1986 forecasts for poor and good productivity are 113,400 t and 172,700 t respectively. For the south coast particularly it is anticipated that poor productivity will prevail, due to unfavorable environmental conditions. The forecast biomass of the major migratory stocks from age-structured model analysis for 1986 is 130,300 tonnes. This predicted run size reflects the downward stock trends in the central coast and south coast and the predictions of poor recruitment because of the currently unfavorable environmental conditions for these areas. The recommended 1986 catch level (20% of the weighted 1986 herring run size) for the B.C. coast is 14,800 t. This includes a recommended closure of the west coast of Vancouver Island where forecast stock biomass is below the CUTOFF level and a 800 t fishery in the Strait of Georgia where forecasts are only minimally above CUTOFF levels"--Abstract, page iv.

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publications.gc.ca/pub?id=9.952780&sl=1

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