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Life-history organization of herring (Clupea harengus pallasi) in the northeast PacificAleaziz, Farzad 14 November 1996 (has links)
The distribution of herring (Clupea harengus pallasi) in
the Northeast Pacific extends from southern California to
northern Alaska. Studies on variation in herring life-history
are limited to local
characteristics and recruitment
populations or relatively restricted regions of the Northeast
Pacific. In this study I assessed herring life-history
patterns and recruitment variation among 14 sites extending
from Lynn Channel in Alaska to San Francisco Bay in
California. Biological data were compiled from published and
of state and provincial
unpublished technical reports
fisheries agencies in the northeast Pacific. Multivariate
(PCA) and inferential statistical methods were applied in
data analysis. Ordinations of length-and weight-at-age
revealed no latitudinal patterns among the 14 herring sites.
Among four sites for which environmental data were available,
there were significant negative correlations between first PC
scores of size and Ekman layer transport and sea-surface
salinity (SSS). Reproductive characteristics of herring
appeared to vary latitudinally. Herring from the more
southerly sites tended to mature at an earlier age and
smaller size and have a longer duration of spawning than
herring from northerly sites. There were significant negative
first PC scores of reproductive
correlations between
variables and Ekman transport, sea-surface temperature, and
SSS. With the exception of Lynn and Seymour Channels in
Alaska, the most northerly sites in this study, asymptotic
to northern
size (L[subscript]���) tended to increase from southern
latitudes. With the exception of southern Strait of Georgia
(British Columbia) herring and Tomales Bay (California)
herring, growth coefficients (K) appeared to be higher in
latitudes. L[subscript]��� was negatively correlated with SST.
Recruitment variation at three sites was related to Ekman layer transport during the
periods of spawning. At San Francisco Bay recruitment was
negatively related to winter Ekman transport. At Sitka and
Island, recruitment showed a
southwestern Vancouver
significant positive and negative correlation, respectively,
Recruitment in northern and
with spring Ekman transport.
southern Strait of Georgia were negatively correlated with
SST during fall. There was no correlation between recruitment
and SSS for all sites. / Graduation date: 1997
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