Reilly, Paul N. and Moore, Thomas O.
Pacific herring, Clupea harengus pallasii studies in San Francisco Bay, December 1981 to March 1982.
Menlo Park, CA,
California Department of Fish and Game, Marine Resources Region,
(Marine Resources Administrative Report, 82-8)
Hydroacoustic monitoring and sampling of San Francisco Bay
herring stocks were conducted from December 1981 to March 1982. Major schools usually were located in central San Francisco Bay between 30 and 90 ft deep prior to spawning. The largest school observed had an estimated volume of 1.5
billion ft3. There was some consistency between the maximum calculated volume of a school prior to spawning and the subsequent spawning biomass estimate, based on egg counts, by Marine Resources Region personnel.
Herring samples were obtained with variable mesh gill nets, a midwater trawl and from commercial purse seine and lampara vessels. Eight discrete spawns were sampled for size and age composition, although data from December and early January samples were biased due to selectivity of the gill net mesh array. In general, a trend was observed of decreasing mean size and age as the season progressed.
Ages of herring ranged from 2 to 9 years. From 87 to 94% of the fish sampled with a midwater trawl, 1.5- to 2.5-in mesh array gill net, and from commercial roundhaul samples consisted of 2-, 3-, and 4-year-olds.
Calculation of desired sample size for future work indicates
that 17 fish per 10-mm size interval need to be aged to determine age composition of each spawning population. (51pp.)
Monograph or Serial issue
||Pacific herring, Clupea harengus pallasii studies in San Francisco Bay, December 1981 to March 1982
|Reilly, Paul N.|
|Moore, Thomas O.|
||Marine Resources Administrative Report
||California Department of Fish and Game, Marine Resources Region
|Place of Publication:
||Menlo Park, CA
||California Department of Fish and Game
||Pacific herring; Clupea harengus pallasii
||03 Oct 2007 11:41
||29 Sep 2011 22:14
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