Tag Archives: invasive species

More Than A Dozen Invasive Green Crabs Found At Dungeness Spit

As if 2015 didn’t deliver enough devastating consequences for Northwest fish and wildlife, it may also be to blame for more than a dozen invasive crabs discovered in the eastern Strait of Juan de Fuca this month.

Allen Pleus at the Washington Department of Fish and Wildlife suspects that the 13 European green crabs found at Dungeness National Wildlife Refuge since April 12 were rafted across the straits as larvae during that wretchedly hot, drought-stricken, conflagration of a summer, probably from Sooke Harbor, 25 miles to the west-northwest on the south end of Vancouver Island.

EUROPEAN GREEN CRAB. (WASHINGTON SEA GRANT)

What’s worrisome is that this is the largest group found since the first one was discovered in Washington waters late last summer, at Westcott Bay on San Juan Island, and along with others that turned up in a mainland estuary, it is beginning to suggest a potentially widespread invasion by the unwanted species.

The news couldn’t come at a worse time, either.

According to Pleus, state funding for monitoring could dry up after June 30.

And the agency that’s been getting everybody on the same page about the problem, Washington Sea Grant, could be closed down at the end of this month as federal programs are targeted for elimination in national budget proposals.

THE DISCOVERY of the crabs at Dungeness Bay by the U.S. Fish and Wildlife Service was predicted.

A Sea Grant map shows the waters around the spit are one of dozens upon dozens of nearshore habitats with a “high probability” of hosting the crabs that first arrived on the US East Coast in the 1800s and “dramatically” affected the Maine clam harvest and damaged kelp beds from their digging.

A WASHINGTON SEA GRANT GOOGLE MAP SHOWS LOCATIONS NEARSHORE HABITATS IN PUGET SOUND AND THE STRAITS WITH HIGH (RED STAR) AND MEDIUM (ORANGE TRIANGLE) SUITABILITY FOR EUROPEAN GREEN CRABS TO TAKE HOLD. THE WHITE CIRCLE REPRESENTS THE LOCATION OF THE 13 CRABS FOUND THIS MONTH, AT DUNGENESS SPIT. (WSG)

The worry here is what the crabs could do to eelgrass pastures — so important for our salmonids and other fish — and clam beds, if they establish a sustaining population.

That appears to be what has happened in Sooke Harbor, where one was found in 2012.

Dungeness is the third spot in Washington the crabs have been found in just the last eight months.

Not long after the discovery at Westcott Bay, one was literally turned up “by chance” by beach walkers at Padilla Bay in mid-September. Three more were subsequently trapped there.

“While I am pleased that the crabs are not more abundant, it’s somewhat concerning that they are distributed so broadly,” P. Sean McDonald, a research scientist at the University of Washington and affiliated with Washington Sea Grant, told the Skagit Valley Herald last September, adding, “One crab doesn’t scare me. Two crabs really isn’t that bad. What’s scary is large numbers of crabs coming in and settling broadly throughout Puget Sound.”

Asked yesterday how alarming the latest discovery is, Pleus paused, then said it was hard to say.

It doesn’t mean there’s an established population in Washington waters yet, and none of those from Dungeness had eggs.

However, they were a mix of males and females, and it’s only a matter of time until waters warm enough for the spawn to kick off. Getting rid of as many breeders as possible is the key to keeping the crabs in check.

Growing to only about 3 inches across the back, there’s not much meat on them.

AS IT STANDS, Washington Sea Grant director Penny Dalton says that estimates to continue the monitoring program run around $180,000.

Even as her agency is in serious danger of elimination — and in part the subject of a scathing opinion piece in the New York Times today against cuts to it and NOAA’s budget — Dalton’s hopeful money can be cobbled together to keep the program running.

“We’re going to keep trying. We think it is really important. WDFW is too,” she says.

Dalton says WDFW’s Allen Pleus is working the Washington legislature to secure funding for the coming budget biennium.

With a very serious threat looming to the health of Puget Sound, this is no time for state or federal lawmakers to get crabby about funding this work to head off this invasion.

FDR Pike Numbers Up As State-Tribal Removal Efforts Intensify

Ten times more “nightmare fish” — northern pike — than last March were caught earlier this month on Lake Roosevelt, including a 20-pound hen carrying eggs that made up roughly a tenth of its body weight.

The unwanted invasive species is the target of stepped-up gillnetting by the Colville and Spokane Tribes, and removal by Washington Department of Fish and Wildlife staffers, who say that this year through March 28, 338 have been taken out of the large reservoir at the head of the Columbia River in Washington.

COLVILLE TRIBES MEMBER ROBERT THOMAS HOLDS UP THE 20-POUND FEMALE NORTHERN PIKE GILLNETTED EARLIER THIS MONTH OUT OF LAKE ROOSEVELT. (BRYAN JONES, COLVILLE TRIBES)

The worry is that, just as pike got loose out of the Pend Oreille River system into Roosevelt, they’ll get out of FDR and into the salmonid-rich Columbia below Lake Rufus Woods.

Managers are increasing their efforts to head them off as they inexorably move that way.

“To date, northern pike appear to be distributed primarily in the Kettle Falls area  — near the mouths of the Colville and Kettle Rivers, Singers Bay, Evans — but juveniles were caught further south, near Bradbury launch, for the first time recently,” says Bill Baker, a WDFW fisheries biologist based in Colville.

He says that 2016 saw recruitment of a “measurable year-class,” along with “confirmed successful spawning” in the Kettle and probably Lake Roosevelt too.

A NORTHWEST POWER AND CONSERVATION COUNCIL IMAGE SHOWS MULTIPLE YEAR-CLASSES OF NORTHERN PIKE GILLNETTED OUT OF THE COLVILLE RIVER EARLIER THIS MONTH, “EVIDENCE THE POPULATION IS GROWING,” ACCORDING TO A BLOG POST FROM THE REGIONAL GROUP. (COLVILLE TRIBES)

“Many of the northern pike caught thus far this year are from that year class, around 16 to 17 inches on average. However, there are some large adults present, as well,” Baker says.

According to a mid-March Northwest Power and Conservation Council blog by spokesman John Harrison and headlined simply “Nightmare Fish,” the gonads on that hefty hen weighed 2.2 pounds and were “stuffed” with eggs.

WDFW began looking for concentrations of pike in February for the tribes to net this month. Gillnetting now gets ahead of the May-June spawn.

Baker says that this year’s netting effort is larger than 2016’s, so it’s hard to compare overall removal numbers from year to year, but he feels the catch rate is up, probably because of more pike in the lake but also a better understanding of where they like to hang out.

“Last year’s efforts informed where and when to net this year,” he says.

Bycatch has been “low,” he says, with walleye and redband rainbows comprising 8 and 5 percent of the overall haul.

Those fish are released alive as much as possible, and that’s being helped by cold water temperatures, he says.

If there’s good news, it’s that removal efforts in the Pend Oreille River reservoirs by the Kalispel Tribe appear to have pinched off those waters as a source of pike for FDR through entrainment during high-runoff years, such as 2011, when they first came to widespread attention after an angler caught one near Kettle Falls.

But unfortunately, the Canadian Columbia now has established pike schools, and “in-reservoir recruitment appears to now be the major driver for population expansion within Lake Roosevelt,” says Baker.

Northerns likely originally came down the Pend Oreille from the Clark Fork and Northwest Montana, where they were illegally introduced over the continental divide by bucket biologists.

State, tribal and Columbia system overseers are all on board with getting rid of as many pike as possible.

“We need to stop pike from moving downstream now,” Colville Tribes principal biologist Holly McLellan told Harrison, who also quoted Guy Norman, a former WDFW regional director and now member of the power council, as saying, “This is something that could have significant ecological effects on the lake, and on fisheries both in the lake and downriver. We need to get on top of it.”

Not only will putting a halt to northern’s southerly advance down the Columbia system help prevent damage to FDR’s stellar trout, kokanee, walleye and bass fisheries and ESA-listed salmon and steelhead populations below Rufus (the tribes also want to reintroduce stocks above Grand Coulee) but also provide fewer pike for jackasses to illegally move around, like the one that turned up in Lake Washington earlier this winter.

Baker says that gillnetting and monitoring will continue through spring.

And Harrison reports that crews will target the shallows this fall to remove and assess juvenile populations, while eDNA testing stations downstream will tell tribal and state monitors if pike are closing in on Grand Coulee Dam or getting into the Columbia Basin Reclamation Project.