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

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<strong>Marine</strong> Mammal Predation<br />

<strong>Marine</strong> mammals are known to attack <strong>and</strong> eat salmonids. Harbor seals (Phoca vitulina),<br />

California sea lions (Zalophus californianus), <strong>and</strong> killer whales (Orcinus orca) prey on<br />

juvenile or adult salmon. Killer whales have a strong preference for Chinook salmon (up<br />

to 78% of identified prey) during late spring to fall (Hard, Jones et al. 1992; Hanson,<br />

Baird et al. 2005; Ford <strong>and</strong> Ellis 2006). Generally, harbor seals do not feed on salmonids<br />

as frequently as California sea lions (Pearcy 1997). California sea lions from the Ballard<br />

Locks in Seattle, Washington have been estimated to consume about 40% of the<br />

steelhead runs since 1985/1986 (Gustafson, Wainwright et al. 1997). In the Columbia<br />

River, salmonids may contribute substantially to sea lion diet at specific times <strong>and</strong><br />

locations (Pearcy 1997). Spring Chinook salmon <strong>and</strong> steelhead are subject to pinniped<br />

predation when they return to the estuary as adults (NMFS 2006). Adult Chinook salmon<br />

in the Columbia River immediately downstream of Bonneville Dam have also<br />

experienced increased predation by California sea lions. In recent years, sea lion<br />

predation of adult LCR winter steelhead in the Bonneville tailrace has increased. This<br />

prompted ongoing actions to reduce predation effects. They include the exclusion,<br />

hazing, <strong>and</strong> in some cases, lethal take of marine mammals near Bonneville Dam (FCRPS<br />

2008).<br />

NOAA <strong>Fisheries</strong> has granted permits to the states of Idaho, Oregon, <strong>and</strong> Washington for<br />

the lethal removal of individual California sea lions that prey on adult spring-run<br />

Chinook salmon in the tail race of Bonneville Dam under section 120 of the <strong>Marine</strong><br />

Mammal Protection Act (NMFS 2006). This action may increase the survival of adult<br />

Chinook salmon <strong>and</strong> steelhead. The Humane Society of the U.S. unsuccessfully<br />

challenged the issuance of these permits. The case is now on appeal.<br />

Avian Predation<br />

Large numbers of fry <strong>and</strong> juveniles are eaten by birds such as mergansers (Mergus spp.),<br />

common murre (Uria aalage), gulls (Larus spp.), <strong>and</strong> belted kingfishers (Megaceryle<br />

alcyon). Avian predators of adult salmonids include bald eagles (Haliaeetus<br />

leucocephalus) <strong>and</strong> osprey (P<strong>and</strong>ion haliaetus) (Pearcy 1997). Caspian terns (Sterna<br />

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