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Monday, April 4, 1994 - Page updated at 12:00 AM

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Eelgrass Making Bigger Waves -- Underwater Plant Now Is Playing Key Role In Shoreline Development

Make room, old-growth forest. Move aside, sagebrush steppe. Another critical Washington ecosystem is drawing the attention of scientists and the dismay of developers:

Underwater eelgrass. Not exactly a household name, but a species that has already affected more than $100 million of shoreside-development projects over the past several years.

Undulating in sinewy green meadows just below Puget Sound's low-tide line, eelgrass can reach lengths up to 6 feet and is a nursery and migratory corridor for key species such as salmon, crab and herring.

Among projects that have been altered, delayed or scrapped because of eelgrass:

-- A proposed Lummi-tribal marina on Lummi Bay north of Bellingham was derailed because its boats would have cut across eelgrass beds.

-- Eelgrass helped torpedo an oil-rig assembly plant proposed by Chicago Bridge & Iron at Whatcom County's Cherry Point and is an argument environmentalists are using against another proposed major dock there.

-- When barges used for sewage-plant construction off Seattle's West Point damaged some eelgrass it was transplanted to mitigate the damage.

-- Mitigation or modifications of expansion plans at Sequim's John Wayne Marina, Anacortes' Ship Harbor Marina, Seattle's Elliott Bay Marina and Swinomish Marina near La Conner have been forced by the plant.

-- Protection of eelgrass was one of several environmental considerations that derailed a Venice-like housing development on Skagit County's Padilla Bay, first proposed by Seattle's Orion Corp. in the 1960s and dead by the 1980s.

"If you are preparing a shoreline development project, the first thing you want to ask is whether there is eelgrass present," warns Eric Johnson, environmental affairs director for the Washington Public Ports Association.

The state Department of Natural Resources, which owns 2 million acres of underwater land in Washington, has adopted an informal "no net loss" of eelgrass policy stricter than state policy for forests or farmland.

But a clear law is lacking.

"DNR and Fisheries and the Department of Ecology have to sit down and work out a more holistic eelgrass policy for the state," says Kurt Fresh, a research scientist who works on eelgrass preservation for the state Department of Fish and Wildlife.

The federal Environmental Protection Agency will be publishing a new report on seagrass policy later this spring compiled by the School of Marine Affairs at the University of Washington.

And Battelle Labs at Sequim is conducting research for the DNR and the Puget Sound Water Quality Authority on ways to minimize eelgrass damage or transplant it. Research has shown the grass dies if it is shaded by docks, subjected to murky water stirred up by boats, exposed to pollution, clawed by bottom-fish nets, or chewed by propellers.

"The techniques for replacing it are pretty iffy," says Thomas Mumford, director of environmental information at the state's division of aquatic lands. Attempts to replant it have had mediocre success.

Eelgrass extends along an estimated 25 percent of Puget Sound's shoreline, or about 400 miles, but is limited by bottom type and depth so it covers just 9 percent of marine waters. "Because the ecosystem is so small its loss is more critical to the survival of some species," says Annette Olson, a UW marine ecologist.

Important food fish especially depend on the eelgrass habitat. Herring lay their eggs on its blades, explains Ron Thom, a research scientist at Battelle. Young salmon hide in it and feed. Dungeness crab spend the first year of their life in its fronds. Diving ducks eat its grass. The grass anchors mud bottoms to control turbidity and erosion, supports algae that fuels the food chain, and decays to fertilize the Sound floor.

It flowers with pale-yellow blossoms and its seeds are released in small bubbles that drift and pop. While in trouble around human development, eelgrass for unknown reasons has expanded in Skagit County's Padilla Bay since the Skagit River was diked and now covers 11,000 acres.

"It's one of the most structurally complex and diverse water habitats," says UW fisheries biologist Charles Simenstad, likening its biological importance to reefs.

Because sub-tidal eelgrass is difficult to see from the surface, no good map of it exists. Battelle researcher Ron Phillips made an almost heroic effort to get an idea of its extent in the 1960s by having himself towed through Hood Canal in scuba gear.

Seagrasses have long been recognized as critical habitat on the East Coast but are rarer on the rocky West Coast. UW biologist Sandy Wyllie-Echeverria has been researching their role from California to Alaska and has learned that Northwest Indians used them for food, medicine and basketry.

He found an invading Japanese variety is expanding, with uncertain environmental consequences. Waterfowl feed on Japonica eelgrass with enthusiasm.

With eelgrass having proved difficult to transplant, the emphasis is switching to protecting it where it naturally grows. One idea is to build docks as narrow and high as possible, with metal gratings or translucent plastic logs that transmit enough light for eelgrass to survive underneath.

Another idea is to trade new development for old. When Anacortes' Trident Sea Foods recently expanded onto eelgrass beds, it removed a nearby old dock to let the meadow recolonize that area.

Copyright (c) 1994 Seattle Times Company, All Rights Reserved.

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