Biological characteristics of the catch from the 1991-92 Pacific herring, Clupea pallasi, roe fishery in San Francisco Bay and Tomales Bay

Abstract

The Tomales-Bodega Bay catch during the past two seasons has been from the northern part of outer Bodega Bay, due to the closure of the Tomales Bay fishery. In the Tomales-Bodega Bay area, 4-, 5-, and 6-yr-old herring, Clupea pallasi, comprised 84% by number of the 1991-92 season's gill net catch. The number of 4-yr-olds increased to 26% of the gill net catch, the second consecutive year that the percentage of 4yr-olds has increased. Four-yr-olds are completely recruited into the gill net fishery, and thus are a good indicator of relative year class strength. Average length of herring in the Tomales-Bodega Bay area gill net catch decreased due to a shift to younger herring in the catch. Herring age and size data obtained from Tomales Bay with a variable-mesh research gill net were similar to data from San Francisco Bay obtained with the same net. Herring over 7-yrs-old were absent from the Tomales Bay variable-mesh gill net and the outer Bodega Bay commercial gill net samples. In San Francisco Bay, the age composition of the gill net catch was again 4-, 5-, and 6-yr-old herring, which comprised 87% of the catch. In the round haul fishery, 3and 4-yr-old herring dominated, comprising 63% of the catch. Recruitment of 2-yr-old herring was poor. The average length of herring in the San Francisco Bay gill net catch was the lowest on record, 189 mm body length (BL). The average length of herring in the round haul catch increased to 179 mmBl due to poor recruitment of young herring. (25pp.