[3] Columbia River Sea Lions And Birds May Soon Be On The Run

Federal agencies are moving ahead with plans to remove ESA-fish munching birds and sea lions from the lower Columbia River, an effort the draft BiOp says will help all ESA-listed stocks.

The Corps of Engineers announced Nov. 5 it had extended the public comment period for the first phase of a program to move Caspian terns from an island near the mouth of the river to a reservoir (Fern Ridge Lake) near Eugene Ore., where a nesting site should be completed by early 2008. The Corps plans to build a one-acre island for the terns.

It's one of six locations--three in Oregon and three at the San Francisco Bay--where the Corps and the U.S. Fish and Wildlife Service will try to transplant the tern population. The lower Columbia population, with its proximity to one of the world's largest bird feeders (the Basin's hatchery program), has grown into the world's largest breeding population of the species, around 9,000 pairs.

The new plan even has the blessing of the Audubon Society. Bird lovers sued the agencies over the government's earlier attempts to move the birds.

"The expanded range of nesting grounds also will provide a diet of fewer Columbia River salmon and support our continued efforts to restore ESA-listed fish in the basin," said Thomas O'Donovan, the Corps' Portland District engineer.

The terns were discovered to eat millions of juvenile salmon and mostly hatchery steelhead after PIT-tags were found on the original nesting grounds farther upriver at Rice Island.

By 2001, the Corps had successfully moved the colony downriver to East Sand Island, where it was thought the birds would have a wider choice of fish species in their diet, thereby lessening their impact on salmon.

Nevertheless, they still consume about 5 million smolts annually, about half what they ate in their upriver location.

However, further research has shown that cormorant consumption of juvenile salmonids near the mouth of the river is comparable to the terns' intake. More research on cormorants is also planned to determine whether they should be managed as well.

The cormorant colony on East Sand Island has grown by nearly 300 percent since 1997, and though smolts make up a small portion of their diet, their sheer numbers have led to a higher overall impact on young salmon and steelhead than from the terns.

An alternative in the tern Environmental Impact Statement that called for the lethal removal of many of the birds was rejected by the Corps, but such drastic action may be used in the future to reduce predation on adult salmon by sea lions near Bonneville Dam.

A task force convened by NOAA Fisheries under the Marine Mammal Protection Act met for six full days this fall and nearly reached consensus (17-1) on a recommendation for approving the Idaho, Oregon and Washington application to lethally remove sea lions. The group did reach consensus on a non-lethal approach to addressing the sea lion problem.

The lone dissenter to the lethal action represents the Humane Society, and did not agree that the sea lions were having a "significant negative impact" on the recovery of ESA-listed fish in the Columbia Basin.

The Corps has estimated that sea lions near the dam consumed about 3 percent of last year's spring chinook run.

Ten members of the task force preferred a lethal alternative aimed at reducing salmon predation to a rolling average of 1 percent within 6 years. Seven members preferred another lethal alternative that would have reduced predation 0.5 percent in the observation area below Bonneville Dam.

If NMFS approves the application for lethal removal of some sea lions, the Marine Mammal Act requires the task force to evaluate the effectiveness of the permitted lethal taking or alternative actions.

If these actions are judged to be ineffective, the task force will be reconvened to recommend additional actions. -B. R.

The following links were mentioned in this story:

Caspian Tern Final EIS Documents

Marine Mammal Protection Act Section 120 Pinniped-Fishery Interaction Task Force Report

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