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

Several of the programs have likely prevented further population extirpations in the ESU.
The contribution of ESU hatchery programs to the productivity of the ESU in-total is
uncertain. The hatchery programs are benefiting ESU spatial structure by increasing the
spawning area utilized in several watersheds and by increasing the geographic range of
the ESU through reintroductions. These programs also provide benefits to ESU diversity.
By bolstering total population sizes, the hatchery programs have likely stemmed adverse
genetic effects for populations at critically low levels. Additionally, measures have been
implemented to maintain current genetic diversity, including the use of native broodstock
and the termination of the programs after 12 years of operation to guard against long-term
domestication effects. Collectively, artificial propagation programs in the ESU presently
provide a slight beneficial effect to ESU abundance, spatial structure, and diversity.
However, artificial propagation programs also provide uncertain effects to ESU
productivity.
Critical Habitat
Critical habitat for this species was designated on September 2, 2005 (70 FR 52630).
Hood Canal summer-run chum salmon have PCEs of: (1) Freshwater spawning, (2)
freshwater rearing, (3) freshwater migration, (4) estuarine areas free of obstruction, (5)
nearshore marine areas free of obstructions, and (6) offshore marine areas with good
water quality. The physical or biological features that characterize these sites include
water quality and quantity, natural cover, forage, adequate passage conditions, and
floodplain connectivity.
Of 17 subbasins reviewed in NMFS’ assessment of critical habitat for the Hood Canal
chum salmon ESU, 14 subbasins were rated as having a high conservation value, while
only three were rated as having a medium value to the conservation. Limiting factors
identified for this species include: (1) Degraded floodplain and mainstem river channel
structure, (2) degraded estuarine water quality conditions and loss of estuarine habitat, (3)
riparian area degradation and loss of in-river wood in mainstem, (4) excessive sediment
in spawning gravels, and (5) reduced stream flow in migration areas. These conditions
also introduce sediment, nutrients, biocides, metals, and other pollutants into surface and
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