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

categories, with mean risk matrix scores ranging from moderately low for spatial
structure to moderately high for abundance and productivity (population growth rate).
Critical Habitat
Critical habitat was designated for this species on September 2, 2005 (70 FR 52488).
The critical habitat designation for this DPS identifies PCEs that include sites necessary
to support one or more steelhead life stages. Specific sites include: (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 47 subbasins reviewed in NMFS’ assessment of critical habitat for the LCR steelhead,
34 subbasins were rated as having a high conservation value. Eleven subbasins were
rated as having a medium value and two were rated as having a low value to the
conservation of the DPS. Limiting factors identified for LCR steelhead include: (1)
Degraded floodplain and steam channel structure and function, (2) reduced access to
spawning/rearing habitat, (3) altered streamflow in tributaries, (4) excessive sediment and
elevated water temperatures in tributaries, and (5) hatchery impacts (NMFS 2005b). The
above conditions also 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.
Middle Columbia River Steelhead
Distribution
Middle Columbia River (MCR) steelhead DPS includes anadromous populations in
Oregon and Washington subbasins upstream of the Hood and Wind River systems to and
including the Yakima River (Figure 27). There are four MPGs with 17 populations in
this DPS. Steelhead from the SR Basin (described elsewhere) are excluded. This
156