Carbaryl, Carbofuran, and Methomyl - National Marine Fisheries ...

overhanging vegetation. Overwintering tends to occur in larger pools and backwater
areas.
North American coho salmon will migrate north along the coast in a narrow coastal band
that broadens in southeastern Alaska. During this migration, juvenile coho salmon tend
to occur in both coastal and offshore waters. During spring and summer, coho salmon
will forage in waters between 46ºN, the Gulf of Alaska, and along Alaska’s Aleutian
Islands.
Status and Trends
Coho salmon survive only in aquatic ecosystems and depend on the quantity and quality
of those aquatic systems. Coho salmon, like the other salmon NMFS has listed, have
declined under the combined effects of overharvests in fisheries; competition from fish
raised in hatcheries and native and non-native exotic species; dams that block their
migrations and alter river hydrology; gravel mining that impedes their migration and
alters the dynamics of the rivers and streams that support juveniles; water diversions that
deplete water levels in rivers and streams; destruction or degradation of riparian habitat
that increase water temperatures in rivers and streams sufficient to reduce the survival of
juvenile chum salmon; and land use practices (logging, agriculture, urbanization) that
destroy wetland and riparian ecosystems. The above activities and features introduce
sediment, nutrients, biocides, metals, and other pollutants into surface and ground water
and degrade water quality in the freshwater, estuarine, and coastal ecosystems throughout
the Pacific Northwest.
Central California Coast Coho Salmon
Distribution
The CCC coho salmon ESU extends from Punta Gorda in northern California south to
and including the San Lorenzo River in central California (Weitkamp, Wainwright et al.
1995). Table 15 identifies populations within the CCC Coho salmon ESU, their
abundances, and hatchery input (Figure 18).
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