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

Populations with the greatest long-term population growth rate are the North Fork
Nooksack and White rivers.
Regarding spatial structure, the populations (22) presumed to be extinct are mostly early
returning fish. Most of these are in the mid- to southern Puget Sound or Hood Canal and
the Strait of Juan de Fuca. The ESU populations with the greatest estimated fractions of
hatchery fish tend to be in the mid-to southern Puget Sound, Hood Canal, and the Strait
of Juan de Fuca. Finally, all but one of the nine extinct Chinook salmon stocks is an
early run population (or component of a population).
Critical Habitat
Critical habitat was designated for this species on September 2, 2005 (70 FR 52630).
The critical habitat designation for this ESU identifies PCEs that include sites necessary
to support one or more Chinook salmon life stages. Specific sites include freshwater
spawning sites, freshwater rearing sites, freshwater migration corridors, nearshore marine
habitat, and estuarine areas. The physical or biological features that characterize these
sites include water quality and quantity, natural cover, forage, adequate passage
conditions, and floodplain connectivity.
Of 49 subbasins (5th field Hydrological Units) reviewed in NMFS’ assessment of critical
habitat for the Puget Sound ESUs, nine subbasins were rated as having a medium
conservation value, 12 were rated as low, and the remaining subbasins (40), where the
bulk of Federal lands occur in this ESU, were rated as having a high conservation value
to Puget Sound Chinook salmon. Factors contributing to the downward trends in this
ESU are hydromorphological changes (such as diking, revetments, loss of secondary
channels in floodplains, widespread blockages of streams, and changes in peak flows),
degraded freshwater and marine habitat affected by agricultural activities and
urbanization, and upper river tributaries widely affected by poor forest practices, and
lower tributaries. Hydroelectric development and flood control also impact Puget Sound
Chinook salmon in several basins. Changes in habitat quantity, availability, diversity,
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