Petition to List Lynn Canal Pacific Herring under the Endangered ...

Figure 6: Alaska Pacific herring (Clupea pallasi) life history model (Figure from NMFS 2005a).
In particular, the egg stage is highly vulnerable to predation, pollution and other sources of
mortality (Rooper et al. 1999). Similarly, juvenile fish are more susceptible to winter starvation
than adults (Foy and Paul 1999).
The demersal egg stage of the Pacific herring may be especially vulnerable to mortality
because they incubate for long periods in shallow locations. Predators can feed for an
extended period on eggs and may exhibit numerical response to the food source. Eggs
can also be susceptible to harsh environmental conditions because they are unable to
move from spawning beds.
(Rooper et al. 1999).
2. Feeding Behavior and Diet
Herring feed on phytoplankton and zooplankton in nutrient rich waters associated with
oceanic upwelling. According to Carlson (1980), copepods are the primary food of Lynn Canal
Herring during the summer, and are primarily composed of larger species that concentrate near
the bottom. Once on the wintering grounds of Auke Bay and Fritz Cove, herring generally cease
feeding (Carlson 1980).
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