Orca habitat at risk if barging allowed, UW scientist testifies

By Keith Ervin
Seattle Times staff reporter

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David Bain said an environmental-impact statement on Glacier Northwest's mining proposal failed to consider recent research that shows noise from boats may be a factor in the decline of the marine mammals.

Bain, an affiliate assistant professor at the University of Washington who is studying the effects of noise on orcas for the National Marine Fisheries Service (NMFS), said the waters off Maury and Vashon islands are an important part of the winter habitat of three whale pods with 84 individuals.

Studies have shown that boat engines and propellers reduce the effectiveness of the sonar-like "echolocation clicks" orcas use to find salmon and other prey, Bain said.

In order to effectively chase fish while females are calving and nursing their young, Bain said, both male and female orcas, also known as killer whales, must be able to use the waters on both sides of Vashon and Maury islands.

If a lengthened pier and noises from tugboats and barges disturb the whales, Bain said, "They won't want to go past it. That could eliminate their use of the Vashon Island area altogether."

Bain said a number of steps — such as limiting the times of year gravel barges visit Maury Island — could reduce the risk to orcas.

NMFS has labeled orcas a "depleted stock" under the Marine Mammal Protection Act and has been ordered by a federal judge to reconsider its earlier decision not to protect the species under the Endangered Species Act.

Glacier Northwest, a Japanese-owned company, is seeking permits to replace a currently unused pier and boost the pace of mining on its 235-acre waterfront property. Company executives told the Shorelines Hearings Board this week the mine is needed to ease a shortage of sand for construction projects in Puget Sound.

King County and three environmental groups — Preserve Our Islands, Washington Environmental Council and People for Puget Sound — have asked the hearings board to uphold the county's denial of permits for the project.

Glacier Northwest won a significant victory in the case last week when the board ruled the barge-dock project is "water dependent," reversing the county's primary rationale for denying the permits.
 
The environmental groups say there are reasons other than water dependency for rejecting the barging operation, especially possible damage to eelgrass beds where herring spawn and salmon find shelter, and risks to an orca population that has fallen to some 5 to 10 percent of its historic size.

While the county opposes the project on legal grounds, it contends its analysis of environmental issues was adequate. A county witness, marine biologist Andrew Wones, is expected to take the stand today to rebut Bain's testimony about possible harm to orcas.

William Cronin, an attorney for Glacier Northwest, said orcas are "a nonissue" because tugs and barges wouldn't greatly increase the amount of boat traffic in the southern part of Puget Sound.

Stephanie Warden, director of the county Department of Development and Environmental Services, also will testify today.

Keith Ervin: 206-464-2105 or kervin@seattletimes.com