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

downstream of Bonneville Dam. Sockeye smolts comprise a very small fraction of the
overall number of migrating smolts (Ferguson 2006) in any given year. The significance
of fish predation on juvenile chum is unknown. There is little direct evidence that
piscivorous fish in the Columbia River consume juvenile sockeye salmon. Nevertheless,
predation of juvenile sockeye likely occurs. The ongoing Northern Pikeminnow
Management Program (NPMP) has reduced predation-related juvenile salmonid mortality
since 1990. Benefits of recent northern pikeminnow management activities to chum
salmon are unknown. However, it may be comparable to those for other salmon species
with a subyearling juvenile life history (Friesen and Ward 1999).
The primary fish predators in estuaries are probably adult salmonids or juvenile
salmonids which emigrate at older and larger sizes than others. They include cutthroat
trout (O. clarki) or steelhead smolts preying on chum or pink salmon smolts. Outside
estuaries, many large fish population reside just offshore and may consume large
numbers of smolts. These fishes include Pacific hake (Merluccius productus), Pacific
mackerel (Scomber japonicus), lingcod (Ophiodon elongates), spiny dogfish (Squalus
acanthias), various rock fish, and lamprey (Beamish, Thomson et al. 1992; Pearcy 1992;
Beamish and Neville 1995).
Wildland Fire
Wildland fires that are allowed to burn naturally in riparian or upland areas may benefit
or harm aquatic species, depending on the degree of departure from natural fire regimes.
Although most fires are small in size, large size fires increase the chances of adverse
effects on aquatic species. Large fires that burn near the shores of streams and rivers can
have biologically significant short-term effects. They include increased water
temperatures, ash, nutrients, pH, sediment, toxic chemicals, and large woody debris
(Buchwalter, Sandahl et al. 2004; Rinne 2004). Nevertheless, fire is also one of the
dominant habitat-forming processes in mountain streams (Bisson, Rieman et al. 2003).
As a result, many large fires burning near streams can result in fish kills with the
survivors actively moving downstream to avoid poor water quality conditions (Greswell
1999; Rinne 2004). The patchy, mosaic pattern burned by fires provides a refuge for
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