Estuary’s
diversity saved by science,
perseverance.
SUQUAMISH — Doe-Keg-Wats Estuary, located near Point Jefferson on the Port Madison Indian Reservation, is a ceremonial and harvesting site to the Suquamish Tribe.
In the native Lushootseed language, it means “place of deer.”
Like all estuarine environments it is known for its local biodiversity, from the great blue heron to juvenile salmon.
According to the U.S. Environmental Protection Agency’s (EPA) National Estuary Program, most estuaries are at risk due to human activities past and present.
Doe-Keg-Wats is no exception. However, its biggest risk is of mother nature’s own creation.
It’s called spartina and it’s believed to be introduced by humans routing goods from the East Coast.
“It’s a type of cordgrass, an exotic species, that is salt tolerant,” said Jay Zischke, marine fish program manager for the Suquamish Tribe. “It’s your classic invasive that displaces natural diversity. Ecologically lots of scientists are worried about it.”
The spartina was first found in Doe-Keg-Wats’ 132 acres of natural vegetation in the mid-1990s, according to a press release by the Northwest Indian Fisheries Commission.
“The spartina root system vigorously spreads while also trapping sediment, interfering with the function of the estuary,” said Tom Curley, geographic information systems manager for the Suquamish Tribe. “It could potentially make Doe-Keg-Wats a meadow, choking out excellent habitat for the juvenile salmon.”
So far, spartina has been found throughout Puget Sound but is most commonly known for invading Willapa Bay, located in the southwest corner of the state.
Due to the spartina invasion, about one-third of Willapa Bay’s 47,000 acres is believed to be marsh land.
According to Friends of Willapa National Wildlife Refuge (www.friendsofwillaparefuge.org/spartina.htm), the spartina likely was introduced in the 1890s as packing material in oyster shipments from the East Coast. It was commonly used in that timeframe as packing material in general cargo shipments.
Zischke said it’s quite possible it was spread the same way to Doe-Keg-Wats.
“It can come in ships. There are lots of organisms that get spread around the world. Think of the bilge water,” he said. “There are so many different ways these things get into our environment because we travel so much nowadays.”
But unlike Willapa Bay, Doe-Keg-Wats’ spartina marshes are well on the way to being eradicated, thus enabling natural local vegetation to take back the area.
Curley, along with aid from Washington Department of Agriculture and the EPA, collaborated on a one and a half acre parcel of the wetland to figure out the best eradication method.
“When we first started in the mid-1990s, we probably removed six or seven pickup trucks full of the plants,” Curley said.
The agencies tried manually removing the plants by digging out the roots, which worked well, only if the roots were fully taken out.
The scientists quickly found that the newly exposed muddy areas were prime conditions for the spartina root fragments to flourish.
“Once it starts growing in clumps it can flower or spread seeds underground and quickly engulfs areas,” Zischke said.
The most successful removal method is to apply the herbacide, Imazapyr, which isn’t toxic to humans, animals or fish.
Imazapyr is the same herbacide used by Washington State Department of Transportation’s Integrated Vegetation Management program and classified as category III low toxicity by the EPA.
Instead of spraying the plants topside, it’s necessary to get the undersides of each plant — even though it is more time consuming, Curley said.
“This was one of the worst infestations in Puget Sound and we’re making some major progress,” he said. “It’s amazing what few spartina plants are left; we’ve probably killed 80 percent of it.”
