Friends at the Coast

Beaver colony gets its teeth into restoration work

By CASSANDRA PROFITA
The Daily Astorian

SEASIDE – A colony of beavers is hard at work building dams up to 100 feet long in Seaside’s Thompson Creek.

The creek is home to one of the largest runs of coho salmon on the North Coast, but it’s floodplain has been choked out by invasive plants.

Much to the delight of leaders at the North Coast Land Conservancy, which owns 80 acres on either side of the creek, the beavers have engineered a way to use invasive plant material to fight further invasion while simultaneously restoring the floodplain and creating juvenile fish habitat.

The beavers moved in and started restoring the creek before the land trust even got a chance to invite them, said NCLC Director Katie Voelke.

“Beavers are like nature’s engineers,” said Voelke. On Thompson Creek, they’ve designed a way to restore wetlands and juvenile fish habitat at a fraction of the cost of a human-engineered restoration project.

NCLC is inviting the public to celebrate beavers and their positive effects on the natural landscape from 10 a.m. to noon Saturday.

Thompson Creek cuts through the 31-lot Thompson Falls Estates subdivision, which was designed to preserve connections between existing streams, tributaries and ponds. The area is living proof that people and beavers can coexist, Voelke said.

Beavers have used invasive blackberry and Scotch broom around Thompson Creek to build dams that are drowning out invasive reed canary grass and clearing the land for native plant growth.

Beaver dams decrease the flow of water in the creek, creating pools where juvenile fish can rest and feed and allowing the creek to spill out into the flood plain and recreate natural wetlands.

The beavers are building dams to secure food for their colony, said Doug Cottam, district biologist with Oregon Department of Fish and Wildlife. But the fringe benefits help fish and other wildlife including elk, who graze on the herbaceous plants in the habitat the dams create.

Cottam is involved with the state’s Beaver Work Group, a diverse team that helps find solutions to conflicts between people and beavers – particularly on salmon-bearing streams. Common problems between beavers and people arise when beavers eat people’s plants or crops or when they cause flooding problems. The work group is currently designing a system of relocating beavers from areas where they are unwanted to areas where they are needed.

“From a biologist’s standpoint, they’re considered a keystone species,” he said. “They play a key role in the stream aquatic environment. They provide very valuable habitat for a variety of fish and wildlife species. They create an environment where vegetation of all kinds grows and insects flourish – they provide an incredible amount of food for other species.”

On Saturday from NCLC will explain how the industrious beavers are restoring an entire ecosystem, one dam at a time. To get to the site, follow Lewis & Clark Road east from U.S. Highway 101 in Seaside for a half-mile to Nygaard Road. A map is available at (www.nclctrust.org/event_beavers2010)

Because the event happens to be during NCLC’s invasive Scotch broom removal Broom Buster week, volunteers will be on the property removing the invasives from 9 a.m. and 3 p.m. To join in that effort, bring gloves and loppers, and pack a lunch.