Biological characteristics of the catch from the 1991-92 Pacific herring, Clupea pallasi, roe fishery in San Francisco Bay and Tomales Bay
1992
Spratt, Jerome D. | Moore, Thomas O.
The Tomales-Bodega Bay catch during the past two seasonshas been from the northern part of outer Bodega Bay, dueto the closure of the Tomales Bay fishery.In the Tomales-Bodega Bay area, 4-, 5-, and 6-yr-oldherring, Clupea pallasi, comprised 84% by number of the1991-92 season's gill net catch.The number of 4-yr-olds increased to 26% of the gill netcatch, 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 areagill net catch decreased due to a shift to younger herringin the catch.Herring age and size data obtained from Tomales Bay with avariable-mesh research gill net were similar to data fromSan Francisco Bay obtained with the same net. Herring over7-yrs-old were absent from the Tomales Bay variable-meshgill net and the outer Bodega Bay commercial gill net samples.In San Francisco Bay, the age composition of the gill netcatch was again 4-, 5-, and 6-yr-old herring, whichcomprised 87% of the catch. In the round haul fishery, 3and4-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 gillnet catch was the lowest on record, 189 mm body length (BL).The average length of herring in the round haul catchincreased to 179 mmBl due to poor recruitment of youngherring. (25pp.)
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