CURBING THE HERB

Volunteers at a local land trust fight invasive species at Crockett Lake, a unique ecosystem home to hundreds of bird species.

Replanting at Crockett Lake on Whidbey Island has been happening since December and was finished in early February. Before planting could occur, more than 40 hectares of the noxious hairy willow herb had to be cleared.

Story by Abby Owen | Photos by Ilana Newman

Whidbey Island lies at the convergence of Puget Sound and the Strait of Juan de Fuca. Nearly halfway down the coast, travelers find themselves boarding the Washington state ferry. But they aren’t the only visitors here. Crockett Lake, just north of the ferry terminal, is an estuary habitat many migratory bird species rely on.

A UNIQUE ECOSYSTEM where freshwater and saltwater meet, Crockett Lake is an important habitat area for birds and other species. The National Audubon Society designated this lake as an important bird area, partly because it is along the Pacific flyway for migratory shorebirds, raptors and song birds. In efforts to preserve this habitat’s biodiversity, the Whidbey Camano Land Trust has spent years tearing out invasive species to make way for native plants. Almost 250 hectares of Crockett Lake are marked as an important area for the conservation of bird populations statewide. Coyotes, rabbits, deer, amphibians, fish and more than 230 bird species can be found there, said Jessica Larson, land steward at the land trust. The trust works to protect and restore habitat on Whidbey and Camano islands.

Volunteers and workers started by removing invasive plants that had taken over much of the land ringing the lake. Hairy willow herb and Himalayan blackberry were the main culprits. The hairy willow herb is an annual plant that can grow two meters tall, sports delicate pink flowers, and has a voracious appetite for wetlands and shorelines. At Crockett Lake, it covered an estimated 40 hectares and competed with the native species in the area. The herb grows and spreads quickly, aggressively crowding out native wetland plants. It’s so invasive, Washington law requires its removal if spotted.

Birds are one reason this weed spread so quickly at Crockett Lake. The birds ate the plant and dispersed the seeds as they flew, said Dyanne Sheldon, a restoration ecologist for Crockett Lake.

An estuary is where freshwater from a river or stream mixes with the saltwater from an ocean. It provides a unique habitat for many riparian species.

Although wetlands can be difficult to reach, the land trust used machinery, manual labor and herbicides to remove the weeds. Since December 2017, the crew has introduced native plants that thrive in the estuary ecosystem, including cottonwoods, sitka spruces and sitka willows.

About three thousand years ago, Crockett Lake transformed from an estuary into a secluded lake after tectonic activity lifted the body of water above sea level, Sheldon said. Later, a tidegate was built, reconnecting the lake with Puget Sound and restoring its status an an estuary.

About half of the world’s natural wetlands have been lost as a result of human activity, according to a 2015 study. Additionally, any given bird population in North America could be as low as 5 percent of what it was before the continent was colonized, said John Bower, professor of ornithology at Western Washington University.

Birds play an important role in the environment. Without them, the food web would be shifted out of balance.

“We would have a hell of a lot more insects,” Bower said.

Crockett Lake has over 230 bird species, including various birds of prey, such as this bald eagle.

Migration is important because it offers a greater variety of food and resources, so birds are able to maximize reproduction, Bower said.

On a January day, workers on the east side of Crockett Lake took off their jackets and hung them on a nearby fence. They spent a moment feeling the sun’s rays as it broke through a cloudy sky. The only task left that day was laying mulch down to help protect the saplings from animals and natural elements.

“Every five minutes we have different weather. You put on a raincoat and then the sun comes back out and it’s beautiful,” said Mark Snyder, a volunteer.

Before moving to the island and working for the land trust, Larson and her sister Amanda grew up in the Auburn area. The trees that once surrounded the home they grew up in are gone, replaced with other houses.

“And that’s why the land trust is so important to me,” Amanda Larson said. “I’ve seen the encroachment and the loss of habitat.”

In several years, Larson says the trust should have enough funding to build a platform on the northern edge of the lake. A quiet viewing spot tucked away from the hustle and bustle of the ferry terminal, the platform would be a special way to appreciate this unique and important lake.