Category Archives: Benthic organisms

Are we at a crossroads in the green crab invasion on Dungeness Spit?

State biologists are holding out hope that the European green crab invasion at Dungeness Spit can be contained. We may now be going through a critical period, which could result in a permanent infestation or possibly the final throes of the invasion.

Green crabs, an invasive species known to displace native species and cause economic devastation to shellfish growers, were first discovered on April 12 in a marshy area on Graveyard Spit, which juts off from the larger Dungeness Spit in the Strait of Juan de Fuca.

The total number of green crabs caught in an ongoing intensive trapping program has reached 76. The weekly numbers have been declining, as shown in a chart on this page. That could be a good sign, but biologists are quite reserved in their predictions.

“The numbers are tapering off,” said Allen Pleus, coordinator of the state’s Aquatic Invasive Species Program, “but in my view the numbers are still too high. Eradication would take several weeks of zero. At this point, our main objective is to bring down the population to a point where spawning would not be successful.”

So far, all of the crabs caught are young and small — about 1 to 2.5 inches across their backs. This means that they have not been in the area for long, probably arriving on last year’s currents in the Strait of Juan de Fuca.

Another good sign is that no other crabs have been caught elsewhere along the Strait, although officials acknowledge that they would like to deploy more traps to capture any early invaders. Also, I am happy to report that no new crabs have been captured this year in Padilla Bay or on San Juan Island, where the state’s first confirmed green crab invasion took place last year. See Water Ways, Sept. 24, 2016.

Update: I’ve been informed that one green crab was caught in April in Padilla Bay where others were caught last year.

The decline in captures at Dungeness Spit may be a sign that some of the crabs have entered their reproductive phase, a period when they don’t eat and so are not attracted to the baited traps. Males and females get together to mate after molting, a phase of development in which they shed their exoskeletons. The trapping effort has reduced the crab numbers and made it more difficult for reproductive males and females to find each other, but each female can produce hundreds of thousands of eggs — so even one successful mating could expand the invasion.

This small male crab is one of the 76 European green crabs caught in traps at Dungeness Spit. // Photo: Allen Pleus

Because the baited traps may not work at this time, officials are experimenting with substrate traps, which are pieces of plastic pipe ranging in size from a half-inch to 2 inches, Allen told me. Young crabs may seek shelter in the tubes. So far, no crabs have been captured that way.

Another idea yet to be tried is baiting traps with pheromones, which are sexual attractants that lure crabs looking for a mate. Allen said he also would like to experiment with electrical stimulation, in which an electrical current is discharged in the muddy substrate to drive crabs out of their burrows. With proper control, no permanent harm comes to them or other creatures in the vicinity, Allen said.

When it comes to controlling future crab invasions in Puget Sound, experts would like to know where the crab larvae are coming from. The leading suspect is a population of green crabs that appear to have settled into Sooke Inlet, just west of Victoria on Vancouver Island in Canada. It is also possible that the larvae drifted in from coastal waters in British Columbia, Washington or even Oregon or California. Experts hope that genetic tests of green crabs from the various locations can be used to identify where the crabs on Dungeness Spit originated.

Emily Grason of Washington Sea Grant coordinates a group of volunteers who monitor traps placed throughout Puget Sound with a goal of stopping the next invasion.

“The presence of green crab in Dungeness Bay, though unfortunate, offers a unique opportunity to test how effective the EDRR (Early Detection-Rapid Response) model is for intervening in a potential green crab invasion,” Emily wrote yesterday in a blog post on the Crab Team website.

“Generally speaking, invasive species are rarely noticed in a new spot until they have already become too abundant to eradicate,” she said. “Though 76 crabs at Dungeness Spit is more than we would ever like to see, the population hasn’t yet reached the numbers that are seen in areas of greatest infestation. And they are, as far as we know, still confined to a relatively small location….

“Preventing and managing biological invasions is similar to planning for a wild fire season: The best thing to do is prevent either invasions or wildfires from taking hold in the first place, but we know that some will occur despite our best efforts. It’s difficult to forecast exactly where, when or how severe they will be when they do pop up, and yet it’s imperative to respond quickly and aggressively as soon as they are detected.”

Emily added that we are fortunate in this area to have the tremendous support of volunteers, partners and beachgoers, all involved in the effort to prevent a permanent invasion of green crabs. Staff and volunteers at the Dungeness National Wildlife Refuge have been instrumental in placing and tending the traps placed in that area.

Amusing Monday: Odd and colorful species make top-10 list for ’17

A newly named stingray that lives in freshwater has joined an omnivorous rat and a couple of leggy wormlike creatures as part of the Top-10 New Species for 2017.

Sulawesi root rat
Photo: Kevin Rowe, Museums Victoria

The top-ten list, compiled by the College of Environmental Science and Forestry (ESF) at the State University of New York, also includes a tiny spider found in India, a katydid discovered in Malaysia and a spiny ant from Papua New Guinea. Two interesting plants also made the list.

It’s often amusing to learn how various critters are first discovered and ultimately how they are named — sometimes for fictional characters with similar characteristics.

ESF President Quentin Wheeler, who founded the International Institute for Species Exploration, said nearly 200,000 new species have been discovered since the top-10 list was started a decade ago.

“This would be nothing but good news were it not for the biodiversity crisis and the fact that we’re losing species faster than we’re discovering them,” he said. “The rate of extinction is 1,000 times faster than in prehistory. Unless we accelerate species exploration, we risk never knowing millions of species or learning the amazing and useful things they can teach us.”

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After environmental restoration, quiet has returned to Port Gamble

Twenty-five years ago, I stood and watched as a screaming buzz saw tossed clouds of sawdust into the air while slicing through thick logs of Douglas fir at the Pope & Talbot sawmill in Port Gamble.

Last week, I walked across the vacant site of the old mill, which was torn down years ago. Along the edge of Port Gamble Bay, I could hear nothing but the sound of the wind and an occasional call of a seagull.

Linda Berry-Maraist, restoration manager for Pope Resources, describes the renewed shoreline along Port Gamble Bay. // Photo: Dunagan

I came back to the old mill site to see how things looked following completion of the $20-million-plus cleanup of Port Gamble Bay. Some 111,000 cubic yards of dredge material is now piled up in the middle of the site, an amount roughly equivalent to 10,000 dumptruck loads.

In addition, nearly 8,600 wooden pilings — most imbedded with creosote — were removed and shipped off for disposal, making it one of the largest piling-removal projects in state history. The final number of pilings removed far exceeded original estimates, largely because buried ones kept turning up during the removal work.

“It’s a huge relief to get this done,” said Jon Rose, vice president of Pope Resources who has overseen a decade of planning and cleanup. “It has been very hard on our staff, hard on the town, hard on our financial statements.

“I think we are on the right side of the mountain,” he added. “Look at how incredible the shore looks.”

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Crab Team training will foster the upcoming hunt for green crab invaders

A European green crab invasion may be taking place in Puget Sound, and Washington Sea Grant intends to enhance its Crab Team this summer with more volunteers looking in more places than ever before.

The second European green crab identified in Puget Sound was found in Padilla Bay, where three others were later trapped.
Photo: Padilla Bay Reserve

Training is about to get underway, and anyone with an interest in furthering science while being exposed to the wonders of nature may participate. It’s not always good weather, but I’ve been inspired by the camaraderie I’ve witnessed among dedicated volunteers.

The work involves going out to one or more selected sites each month from April into September with a team of two to four other volunteers. It is helpful to have folks who can carry the crab traps, plastic bins and other equipment. For details, check out the Washington Sea Grant website.

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Stream ‘bugs’ will help guide funding for future stream restoration

One of the goals established by the Puget Sound Partnership is to improve freshwater quality in 30 streams throughout the region, as measured by the Benthic Index of Biotic Integrity, or B-IBI.

Benthic invertebrates range in size from those easily seen with the naked eye to those that cannot be spotted without the use of a microscope. Photo: C. Dunagan
Benthic invertebrates range in size from those easily seen with the naked eye to those that cannot be spotted without the use of a microscope. // Photo: C. Dunagan

Simply described, B-IBI is a numerical measure of stream health as determined by the number and type of bottom-dwelling creatures that live in a stream. My latest article published in the Encyclopedia of Puget Sound describes in some detail how this index works. Here’s the basic idea:

“High-scoring streams tend to have a large variety of ‘bugs,’ as researchers often call them, lumping together the benthic species. Extra points are given for species that cannot survive without clean, cool water. On the other hand, low-scoring streams are generally dominated by a few species able to survive under the worst conditions.”

Because benthic invertebrates have evolved over time with salmon and other fish, many of these important “bugs” are primary prey for the fish that we value highly. Said another way, “healthy” streams — as measured by B-IBI — tend to be those that are not only cool and clean but also very good habitats for salmon.

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More invasive crabs found; wider search will resume next spring

Padilla Bay, an extensive inlet east of Anacortes in North Puget Sound, could become known as an early stronghold of the invasive European Green crab, a species dreaded for the economic damage it has brought to other regions of the country.

Trapping sites for crabs (gray markers) during this week’s rapid assessment in Padilla Bay. The red markers show locations where invasive European green crabs were found.
Trapping sites for crabs (gray markers) during this week’s rapid assessment in Padilla Bay. Red markers show locations where three more invasive European green crabs were found.
Map: Washington Sea Grant

After one young green crab was found in Padilla Bay on Sept. 19 (Water Ways, Sept. 24), three more crabs were found during an extensive trapping effort this past week. All four crabs were captured at different locations in the bay. These four live crabs followed the finding of a single adult green crab in the San Juan Islands — the first-ever finding of green crabs anywhere in Puget Sound. (Water Ways, Sept. 15).

With these new findings in Padilla Bay, the goal of containing the crabs to one area has become a greater challenge. Emily Grason, who coordinates a volunteer crab-surveillance program for Washington Sea Grant, discusses the difficulty of putting out enough traps to cover the entire bay. Read her report on the fist day of trapping:

“Similar to our trip to San Juan Island, we are conducting extensive trapping in an effort to learn more about whether there are more green crabs in Padilla Bay. One difference, however, is scale. Padilla Bay is massive, and it’s hard to know exactly where to start. On San Juan Island, the muddy habitats where we thought crabs would do well are well-defined, and relatively limited. Padilla Bay, on the other hand, is one giant muddy habitat — well, not all of it, but certainly a huge portion. We could trap for weeks and still not cover all of the suitable habitat!”

In all, 192 traps were set up at 31 sites, covering about 20 miles of shoreline. The crab team was fortunate to work with the expert staff at the Padilla Bay National Estuarine Research Reserve, a group of folks who know the area well and had worked with shoreline owners to get approval for access.

Three of the four green crabs caught in Padilla Bay were young, probably washed into the bay during last winter’s warm currents, Emily said in her wrap-up report of the effort.

“All of the detections of European green crabs occurred on the east portion of the bay,” she wrote. “Though the sites varied somewhat in the type of habitat, all of the crabs were found relatively high on the shore, in high salt marsh pools, or within a few meters of the shore.

The first of four European green crabs found in Padilla Bay. Photo: Padilla Bay Reserve
The first of four European green crabs found in Padilla Bay.
Photo: Padilla Bay National Estuarine Reserve

“Padilla Bay has about 20 miles of shoreline, and, at last count in 2004, there were 143 acres of salt marsh habitat in the bay,” she continued.”These numbers suggest that there are a lot of places European green crabs could live in Padilla Bay, and protecting the bay from this global invader will undoubtedly require a cooperative effort.”

Yesterday, the response team held a conference call to discuss what to do next. Team members agreed that no more intensive trapping would take place this year, Sean McDonald of the University of Washington told me in an email.

Winter is a tough time to catch crabs. Low tides shift from daytime hours to nighttime hours, making trapping more difficult. Meanwhile, crabs tend to lose their appetite during winter months, so they are less likely to go into the traps to get food, experts say.

Researchers, shellfish growers and beach walkers are being asked to stay alert for the green crabs, not only in Padilla Bay but also in nearby Samish and Fidalgo bays.

The Legislature will need to provide funding to continue the citizen science volunteer monitoring program, which provided an early warning that green crabs had invaded Puget Sound. Whether the crabs will survive and in what numbers is something that demands more study and perhaps a major eradication effort.

Meanwhile, Washington Department of Fish and Wildlife would like to expand its overall Aquatic Invasive Species Program with additional efforts to prevent invaders from coming into Puget Sound. For information, check out my story on invasive species in the Encyclopedia of Puget Sound — specifically the section titled “Biofouling still mostly unregulated.”

A single green crab invader has been found, the first in Puget Sound

A European green crab, one of the most dreaded invasive species in the world, has finally arrived in Puget Sound.

Caught in a crab trap on San Juan Island were these animals — including the first European green crab ever found in Puget Sound. Photo: Photo Craig Staude, courtesy of Washington Sea Grant
Caught in a crab trap on San Juan Island were these fish, along with the first European green crab ever found in Puget Sound.
Photo: Craig Staude, courtesy of Washington Sea Grant

A single adult green crab was caught in a trap deployed on San Juan Island by a team of volunteers involved in a regionwide effort to locate the invasive crabs before they become an established population.

Until now, green crabs have never been found in Puget Sound, although they have managed to establish breeding populations along the West Coast — including Willapa Bay and Grays Harbor in Washington and the western side of Vancouver Island in British Columbia.

Coincidentally, I recently completed a writing project on invasive species for the Encyclopedia of Puget Sound, including a story about green crabs and the volunteer monitoring program.

Here’s what I wrote: “Puget Sound has so far avoided an invasion of European green crabs — at least none have been found — but the threat could be just around the corner….

“Green crabs are but one of the invasive species threatening Washington state, but they are getting special attention because of fears they could seriously affect the economy and ecosystem of Puget Sound. Besides devouring young native crabs and shellfish, they compete for food with a variety of species, including fish and birds.”

Along the beach, careful observers can often find crab molts. The green crab, upper left, can be distinguished by the points on its carapace. Photo: Jeff Adams, Washington Sea Grant
Along the beach, careful observers may find weathered crab molts of all sizes. The green crab, upper left, can be distinguished by the five points on each side of the carapace. (Click to enlarge.)
Photo: Jeff Adams, Washington Sea Grant

In Canada, one breeding population has been identified in Sooke Inlet near the southernmost tip of Vancouver Island. That’s about 40 miles away from Westcott Bay, where Puget Sound’s first green crab was found on Tuesday.

It is likely that the crab traveled to San Juan Island in its early free-swimming larval form by drifting with the currents, said Jeff Adams, a marine ecologist for Washington Sea Grant who manages the Crab Team of volunteers. This crab likely settled down in suitable habitat and located enough food to grow into an adult. Based on the crab’s size, it probably arrived last year, Jeff told me.

European green crab Photo: Gregory C. Jensen, UW
European green crab // Photo: Gregory Jensen, UW

Finding a green crab in Puget Sound is alarming, Jeff said, but it is a good sign that the first crab was found by the volunteer monitors. That suggests that the trapping program is working. If this first crab turns out to be a single individual without a mate, then the threat would die out, at least for now.

The concern is that if one crab can survive in Puget Sound, then others may also be lurking around, increasing the chance of male-female pairing. The next step is to conduct a more extensive trapping effort in the area where the first green crab was found, then branch out to other suitable habitats in the San Juan Islands, Jeff said. The expanded effort is planned for the week of Sept. 11 and will include a search for molts — the shells left behind when crabs outgrow their exoskeletons and enter a new stage of growth.

Green crab
Green crab

Researchers and others who work with invasive species quickly recovered from their initial surprise at finding a green crab in Puget Sound, then got down to business in planning how to survey for crabs and manage their potential impacts.

Allen Pleus, coordinator of the Aquatic Invasive Species Program at the Washington Department of Fish and Wildlife, told me several weeks ago that if green crabs show up in Puget Sound, one idea would be to conduct an extensive trapping program to eradicate or at least reduce their population. First, however, the extent of the infestation must be identified. I expect that more extensive trapping will be planned next spring and summer to look for offspring from any successful mating in the San Juan Islands.

This video shows a green crab found in Willapa Bay on the Washington Coast.

Typically, green crabs are found in marshy areas, which are habitats extensively used by our native hairy shore crab. But Jeff tells me that some populations of green crabs seem to be expanding their habitat into more exposed rocky areas.

With roughly 400 suitable sites for the crabs in Puget Sound, invasive species experts are calling for everyone who visits a beach to look for green crabs and their molts. One can learn to identify green crabs from the Washington Sea Grant website. The volunteer trapping program is funded by the Environmental Protection Agency with a grant to Fish and Wildlife.

A public discussion about green crabs and how people can help protect Puget Sound from an invasion is scheduled for Sept. 13 at Friday Harbor Laboratories on San Juan Island. See Crab Team Public Presentation.

Amusing Monday: Purple sea creature becomes an unlikely video star

Purple stubby squid is a real creature from the deep sea. Photo: EV Nautilus/YouTube
Purple stubby squid is a real creature from the deep sea.
Photo: EV Nautilus/YouTube

Wait! Don’t touch that! It’s not a toy. It’s a living thing.

Researchers aboard the Exploration Vessel Nautilus were scanning the seafloor off the coast of California using an unmanned submarine when they spotted a purple thing that caused them to laugh with amusement.

“It looks so fake,” one researcher said. “It looks like some little kid dropped their toy.” (Watch and listen in the first video player on this page.)

They maneuvered the remotely operated vehicle Hercules closer and continued to laugh at the creature with eyes that looked glued on. Later, as the video went viral, this purple cephalopod — a class that includes squid, octopus and cuttlefish — became known to many people as the “googly eyed squid.” Since Aug. 12, more than 2.5 million viewers have clicked on the video.

This species, Rossia pacifica, is known to Puget Sound divers as the stubby squid or sometimes the bobtail squid, but it is not a true squid. See The Cephalopod Page by James Wood to understand the relationship among family groups.

This particular stubby squid was seen in early August on the seafloor about 2,950 feet deep off the California Coast. They can be found from throughout the North Pacific south to Southern California. They are found at many depths from coastal waters to inland seas.

The second video shows a bobtail squid spotted from the EV Nautilus in August of 2014, and the third shows a flapjack octopus from August of 2015.

Roland Anderson of Seattle Aquarium described early surveys in Puget Sound, where stubby squids were found in muddy sand at 11 sites between Seattle and Tacoma, including Elliott and Commencement bays. Check out “Field Aspects of the Sepiolid Squid.” (PDF 3.3 mb)

In a piece on “The Cephalopod Page,” Anderson writes, “One surprising thing recently learned about stubby squid is that they are found in polluted urban bays with highly polluted bottom sediments, such as the inner harbors of Seattle and Tacoma.

“There may be several reasons they can survive there. Deposition from rivers maybe capping polluted sediments. Their short life spans (just two years from eggs) may not allow them to absorb a significant amount of pollutants from the sediments. Another survival factor may be the stubby squid’s ability to produce copious quantities of mucus, which may protect it from the sediments like a thick Jello jacket.”

Reporter Stefan Sirucek of National Geographic News interviewed Michael Vecchione, a cephalopod expert at the Smithsonian National Museum of Natural History.

“It’s not an uncommon species,” he said. “They get all the way from scuba-diving depths down into the deep sea. If that is all one species, then it’s pretty broadly distributed.”

Vecchione said large eyes are fairly common among deep-see animals.

“They are funny-looking eyes, but I’ve seen other species of this genus that had eyes that looked very similar,” he said. “People were actually asking whether those eyes were photo-shopped in to make it look more like a cartoon or something. No, those are the real eyes. That’s what they look like.”

In low light, the big eyes help them hunt for crustaceans and avoid predators. In either case, the strategy is to remain still so other animals don’t notice it there, which can make it look like a child’s toy.

“My guess is it was probably frozen because of this big machine that was brightly lit up in front of it,” Vecchione said in the interview. “So it was trying not to be seen, basically.”

Invasive species hitching a ride into Puget Sound

We hear about the “balance of nature,” but it’s not something that we can truly understand until the balance is thrown out of whack by something like climate change or invasive species.

Until I began a recent reporting project for Puget Sound Institute, I never realized that San Francisco Bay was such a hotbed of invasive species. Beginning with the California Gold Rush, ships began moving in and out of the bay in unbelievable numbers, arriving from ports all around the world. Now, more than 200 non-native species are making their permanent home in the bay — including some species that have thoroughly altered the local ecosystem.

So far, we have been lucky in Puget Sound. Experts say we have about 75 firmly established non-native species, yet none of them have created the widespread damage caused in San Francisco Bay by European green crabs and Asian clams or in the Great Lakes by zebra mussels. The video on this page does a good job of telling the Great Lakes story, which has been repeated all over the world.

Once people in Washington state realized how disruptive invasive species can be, the struggle was on to protect Puget Sound from alien invaders — particularly those found in San Francisco Bay, which is just a short hop away on the world scale. My series of stories talks about concerns for Puget Sound and the efforts to control a possible invasion.

Three weeks ago in Water Ways, I described legislation that would reduce state and federal controls over invasive species. See “Bill could increase risks of alien species invasions in Puget Sound waters.”

On the East Coast, where they are native, striped bass are one of the most popular sport fish. Here, Angela Anning of Connecticut shows off her impressive striper. On the West Coast, striped bass could be considered an invasive species. Photo: NOAA
On the East Coast, where they are native, striped bass are one of the most popular sport fish. Here, Angela Anning of Connecticut shows off her impressive striper. On the West Coast, striped bass could be considered an invasive species.
Photo: NOAA

Invasive species range in size from microscopic viruses to four-foot-long striped bass. In California, the striped bass became a prized sport fish after it was intentionally introduced in 1879. But over the past decade concerns have grown for their effects on the salmon population. The jury is still out on whether high numbers of stripers should be sustained for anglers or the population should be fished down rapidly to save salmon and other species. Check out these stories:

Meanwhile, striped bass have been moving up the West Coast, possibly because of warmer waters due to climate change. A few years ago, a 55-pounder was caught in the Columbia River, and I’ve heard rumors that they have been seen in the Strait of Juan de Fuca.

On the small side, I report on a tiny crustacean, an invasive copepod that has almost entirely displaced native copepods in Samish Bay in northern Puget Sound. Copepods are important prey for small fish, including herring, which feed the larger salmon. The invasive copepods are smaller and more difficult for fish to see, which could have a cascading effect on the entire food web.

Invasive copepod Oithona davisae under magnification Photo: Jeff Cordell, University of Washington
Invasive copepod Oithona davisae
Photo: Jeff Cordell, UW

A major concern for Puget Sound biologists is the European green crab, which could move into Puget Sound from San Francisco Bay in ballast water or with warm ocean currents during an El Niño year, like the one just past. As I describe in the new series, a major program involving citizen science volunteers is ongoing in a search to find the first green crabs before they gain a foothold.

Pacific oysters, another non-native species, were intentionally brought to the Northwest from Japan in the early 1900s to replace the native Olympia oyster, which had been decimated by poor water quality. Pacific oysters soon became a mainstay of the shellfish industry in the Puget Sound region and are now growing thick in numerous areas.

European green crab Photo: Washington Sea Grant
European green crab
Photo: Gregory C. Jensen, UW

Similar introductions of Pacific oysters occurred in California beginning more than 100 years ago, but for some reason the oyster populations never took hold, according to a report in the publication California Fish and Game (PDF 1.7 mb). Finally, in the early 2000s, the invasion began to take off.

“It remains unclear why there should be a successful invasion now, given the failure of previous attempts to deliberately introduce the species both locally and throughout California…,” the report says.

“If populations in Southern California waters do continue to expand and grow, as they have in other areas where they have invaded, it will undoubtedly bring changes to the way our estuarine intertidal habitats function as well as in the way we must manage them.

Pacific oyster Photo: Washington Sea Grant
Pacific oyster
Photo: Washington Sea Grant

“Because Pacific oysters rapidly reach large sizes, they could pose problems related to fouling of maritime equipment, infrastructure, and vessels,” the report continues. “Pacific oysters stand out as one of the most transformative invaders of marine ecosystems.”

As Washington state takes steps to keep alien species from invading Puget Sound from California, California officials may adopt similar measures to block invaders from coming into that state.

Please take a look at this package of stories I wrote for Puget Sound Institute, with editing by Jeff Rice and design by Kris Symer:

Big sea stars, but no babies, observed
in Lofall this week

“Still no babies,” commented Peg Tillery, as we arrived at the Lofall dock in North Kitsap in search of sea stars clinging to pilings under the dock.

Barb Erickson examines sea stars at the base of a pier in Lofall. Photo: Christopher Dunagan
Barb Erickson examines sea stars at the base of a pier in Lofall on Hood Canal.
Photo: Christopher Dunagan

“They say there’s a comeback of the little ones,” noted Barb Erickson, “but I’m not seeing any of them.”

Peg and Barb are two of three retired volunteers who first brought me to this site two years ago to explain their ongoing investigation into the mysterious “sea star wasting disease.” Since our first trip, researchers have identified the virus that attacks sea stars, causes their arms to fall off and turns their bodies to a gooey mush.

I first witnessed the devastation in June of 2014, when starfish were dying by the millions up and down the West Coast (Water Ways, June 17, 2014). Lofall, a community on Hood Canal, was just one location where the stars seemed to be barely clinging to life. Now, just a fraction of the population still survives in many locations.

Bruce Menge of Oregon State University recently reported an upsurge in the number of baby starfish on the Oregon Coast, something not seen since the beginning of the epidemic.

“When we looked at the settlement of the larval sea stars on rocks in 2014 during the epidemic, it was the same or maybe even a bit lower than previous years,” said Menge in a news release from OSU. “But a few months later, the number of juveniles was off the charts — higher than we’d ever seen — as much as 300 times normal.”

As Peg and Barb pointed out, the recovery at Lofall has been hit or miss during more than two years of monitoring the site. I became hopeful on my return trip to the dock in January of 2015, when I noticed a mix of healthy adult and juvenile sea stars (Water Ways, Jan. 20,2015).

This week, the young ones were nowhere in sight. Clusters of healthy adult ochre stars were piled on top of each other at the bottom of the piers, waiting for the tide to come back in. I was not sure what to make of it.

Sea stars clusters on two adjacent piers at Lofall dock. Photo: Christopher Dunagan
Sea stars clusters on two adjacent piers at Lofall dock.
Photo: Christopher Dunagan

“it could be worse,” Barb said. “I think it is neutral news.” Peg agreed, saying, “It could be totally worse.”

Summer has been the period of reckoning in past years, and we should soon know if we are in for another round of disease, which could kill off more of the surviving sea stars, or if the disease is finally on the wane.

Linda Martin, who normally compiles the data, was not along on this week’s trip to Lofall, but other volunteers filled in for her.

“It is an interesting ride,” Barb told me, referring to her experience as a so-called citizen scientist. “It connects you to the larger picture, and you realize that everything is connected.”

It is nice for people in the community to know that this volunteer work is taking place, Barb said, and that someone is watching for changes in the environment.

“People will come up and ask me if there is anything new, people who couldn’t have cared less before,” she said.

For those interested in this kind of volunteer work, a good place to start is Kitsap Beach Naturalists. One can contact Renee Johnson, program coordinator, at rkjohnson@co.kitsap.wa.us.

Meanwhile, the cause of sea star wasting disease remains somewhat of a mystery even after its connection to the densovirus, which is associated with dead sea stars but also has been found in some that are free of disease.

A laboratory study led by Morgan Eisenlord of Cornell University found that the disease progressed faster when adult sea stars were exposed to higher temperatures and that adult mortality was 18 percent higher when water temperatures reached 66 degrees F. Temperature was documented as a likely factor in the spread of disease through the San Juan Islands.

But temperatures are not the sole controlling factor, because the spread of the disease has been out of sync with temperature change in numerous locations.

“The sea temperatures were warmer when the outbreak first began,” Menge said, “but Oregon wasn’t affected as early as other parts of the West Coast, and the outbreak reached its peak here when the sea temperature plummeted and was actually cooler than normal.”

Could there be another trigger that increases the virulence of the densovirus?

“Ocean acidification is one possibility, and we’re looking at that now,” Menge said. “Ultimately, the cause seems likely to be multi-faceted.”