Shellfish

Tag: Shellfish

Can biologists estimate the massive loss of shellfish caused by low tides, high temps?

The putrid smell of rotting shellfish on some beaches in Puget Sound and elsewhere along the West Coast were a clear sign that large numbers of clams, mussels, oysters and other intertidal creatures were killed from exposure to extreme low tides, record-breaking temperatures and a blazing hot sun.
The total losses of shellfish that perished late last month may be difficult to estimate, but experts are beginning to piece together evidence from shoreline residents, state and tribal biologists, and commercial shellfish growers. Their goal is to describe what took place during the record-breaking temperatures of June 25-29 during some of the lowest tides of the past century.

The recent heatwave killed large numbers of shellfish throughout Puget Sound, including these butter clams in Quartermaster Harbor, Vashon Island. // Photo: Ron Carr

Understanding what happened during that June event might help avoid future shellfish disasters as the climate continues to change with no end in sight, officials say.
“We’ve been getting reports from Puget Sound to Canada, including the outer coast,” said Teri King, a shellfish biologist with Washington Sea Grant. “The effects of the heatwave were not uniform. Some areas got hammered and some seemed to escape (the problems).”
Tori Dulemba, who lives on the North Shore of Hood Canal near Tahuya, owns a south-facing beach with a gradual slope. Those conditions led to a long period of exposure to the hot sun when afternoon tides were the lowest since 2008 and when temperatures soared well above 100 degrees.
“You could easily smell the rotting shellfish,” Tori told me. “We knew immediately what it was. The oysters were cooked. The mussels were still attached, but the shells were empty. It was heart-breaking.”
The odor, she said, was much like the smell of dead salmon in areas where large numbers of fish still return to spawn and die in the streams. After a few days, the smell of dead shellfish dissipated, and it was gone after a week or so, but empty shells remained.
Teri King, who coordinates the Bivalves for Clean Water citizen education and monitoring program, said the first reports she received included descriptions of stressed clams digging themselves out of the ground and opening up on the surface of various beaches.
Based on reports, it seems that sand dollars were the first to succumb, followed by cockles, varnish clams, mussels, littleneck clams and butter clams, she said. There were also reports of dead Olympia oysters and Pacific oysters. Even barnacles turned up dead, while some sea stars and anemones also were killed.
A large number of the big moon snails common to Puget Sound got so hot that they literally uncurled themselves and came out of their shells, lying like balls on the beach, Teri said.
During the recent heatwave, tide levels were among the lowest in the past century. At Union on Hood Canal, shown here, the level was estimated to be at -4.37 feet at noon on June 25. Click to visit NOAA’s website for more specific data. // NOAA Tide Predictions

It seems that some areas were more sheltered from the sun or less affected by low tides because of the slopes of the beaches or the direction they faced. In general, problems were worse in South Puget Sound than in the north, Teri said, probably because the tides are more pronounced the farther south you go, leaving shellfish exposed for longer periods of time.
Teri and other officials are still taking observations and photographs from shoreline observers who were able to note the effects on shellfish caused by the extreme and extended heat. The Washington Department of Fish and Wildlife has provided an online form for observers to fill out, or they can send their information by Email.
Camille Speck, intertidal shellfish manager for WDFW, confirms the hit-and-miss nature of the massive shellfish die-off. While some public beaches were affected, others seem to have gotten by with minimal effects.
“What we saw at Dosewallips was very heartening,” Camille told me. “One-year-old or two-year-old oysters seemed to be doing just fine.”
She was speaking of Dosewallips State Park, a popular beach open to the public for shellfish harvesting. The beach lies on the western shoreline of Hood Canal, which may be better sheltered from the heatwave than the eastern shore or the northern shore around the “bend”.
Camille has yet to survey a number of public beaches, so she can’t say whether recreational shellfish seasons might need to be shortened to ensure future production. In some cases, quotas may be adjusted next year to compensate for losses, depending on the number of recreational harvesters and the amount of shellfish taken the rest of this year.
Photo: Ron Carr, Quartermaster Harbor

It was like a “perfect storm,” having such extreme low tides occurring coincidentally during the record-breaking heat, Camille said. Only two tidal periods in the last 100 years — one in 2008 and the other in 1916 — were lower, she said, and the temperatures climbed to levels never seen before in many places.
In Seattle, for example, the city had experienced 100-degree temperatures only three times in the past 126 years before they reached that level three days in a row, breaking the all-time record with 104 degrees on June 27 and again the next day with 108 degrees.
Meanwhile, some commercial shellfish growers have been gathering information to record their losses and possibly receive disaster relief from the federal government. Recent revisions to a federal program called Emergency Assistance for Livestock, Honey Bees and Farm-raised Fish (ELAP) may provide compensation for growers who can document their losses to the U.S. Department of Agriculture, officials say. For information, contact your county office of the Farm Service Agency.
A major hurdle in coming up with an estimate of actual losses — for commercial or noncommercial shellfish beds — is knowing what shellfish were present before the heatwave killed a portion of the shellfish.
Margaret Pilaro, executive director of Pacific Coast Shellfish Growers Association, said it is her understanding that growers must notify the USDA of potential losses within 30 days of the event. She has been trying to notify all of Washington’s certified shellfish growers of the possibility for financial aid to make sure that they don’t miss the deadline.
Tribal biologists also are out surveying the shellfish die-off, especially in areas where tribes have plans to harvest shellfish, as allowed by treaty. For state and private lands not cultivated for shellfish, the tribes are entitled to half the harvestable amount.
Biologists hope that a rough estimate of the total damage caused by the heat and low tides can be achievable, although such an estimate will be complicated by the patchy nature of the losses as well as the uncertainty about what was present in some areas before the event. For now, the main focus is to gather information from as many beaches as possible throughout Puget Sound.

In the topsy turvy world of climate change, Western Canada to the north experienced a similar but even more punishing heatwave, according to Tom Di Liberto, a meteorologist with CollabraLink Technologies. He says Lytton, British Columbia, reached 116 degrees on June 27, breaking the all-time record for all of Canada. But the oppressive weather was not over, as the temperature rose to 118 degrees the next day and then to 121 degrees on June 29. That is hotter than the desert town of Las Vegas, Nev., has experienced since records were first kept, according to Tom.
Likewise, the shellfish in British Columbia were reported to be cooking on the beach, perhaps even worse than in Puget Sound, as reported by Canadian news outlets.
Chris Harley, a marine biologist at the University of British Columbia, threw out an estimate of a billion shoreline creatures perishing in the Salish Sea as a result of the heat. That number, reported by Alex Migdal of CBC News, was crudely calculated by expanding the findings from a small area. The number subsequently raised a lot of eyebrows among experts on both sides of the border — but who could dispute it?
Commenting on the estimate, Chris Neufeld of Bamfield Marine Sciences Centre on Vancouver Island, said he was not surprised, adding, “It was very disheartening to realize we’re actually in this moment that we’ve been predicting for a long time.”

Olympia oysters. Photo: VIUDeepBay (CC BY 2.0) https://www.flickr.com/photos/viucsr/5778358466

Grant funding to study climate change risks to shellfish

The Environmental Protection Agency’s National Estuary Program has issued a call for proposals for research into climate change risks to Puget Sound shellfish, marine water quality and public health.  A total of $150,000 is available to fund up to three projects. Applications are due by 11:59 PM on April 8th. The full call for proposals is available online from the Puget Sound Partnership.

Six-month-old Olympia oyster (Ostrea lurida) seed. Photo: Benjamin Drummond/benjandsara.com

Return of a native: Olympia oysters are making a comeback

Prior to European settlement, dense assemblages of Olympia oysters covered as many as 20,000 acres, or 26.7% of Puget Sound’s intertidal zone. Today they occupy about 5% of their original range, prompting a slew of state and federally-funded restoration efforts.
Sarah DeWeerdt reports on the comeback of Puget Sound’s only native oyster for our magazine Salish Sea Currents.
 
 

Removal of creosote-treated pilings in Puget Sound. Photo courtesy of the Washington State Department of Natural Resources.

Removal of creosote-treated pilings may assist herring recovery

Thousands of abandoned wood pilings — the ghosts of piers and docks past — are located throughout Puget Sound. Most of them are treated with creosote, a toxic chemical used to preserve wood that contains polycyclic aromatic hydrocarbons (PAHs), a class of chemicals that are also associated with oil spills and burning of fossil fuels.
While creosote-treated pilings are used less for construction of new piers, scientists at two state agencies are now studying the impacts of existing pilings on herring and shellfish populations along with the effectiveness of removal projects.
Read the story by Megan Feddern in Salish Sea Currents.

Removal of creosote-treated pilings in Puget Sound. Photo courtesy of the Washington State Department of Natural Resources.

Removal of creosote-treated pilings may assist herring recovery

Thousands of abandoned wood pilings — the ghosts of piers and docks past — are located throughout Puget Sound. Most of them are treated with creosote, a toxic chemical used to preserve wood that contains polycyclic aromatic hydrocarbons (PAHs), a class of chemicals that are also associated with oil spills and burning of fossil fuels.
While creosote-treated pilings are used less for construction of new piers, scientists at two state agencies are now studying the impacts of existing pilings on herring and shellfish populations along with the effectiveness of removal projects.
Read the story by Megan Feddern in Salish Sea Currents.

Bay Mussels (Mytilus trossulus) on Edmonds Ferry Dock. Photo [cropped]: brewbooks (CC BY-SA 2.0) https://www.flickr.com/photos/brewbooks/8840874065

Bay mussels in Puget Sound show traces of oxycodone

By Jeff Rice
The opioid epidemic has now hit the waters of Puget Sound. State agencies tracking pollution levels in Puget Sound have discovered traces of oxycodone in the tissues of native bay mussels (Mytilus trossulus) from Seattle and Bremerton area harbors.
The mussels were part of the state’s Puget Sound Mussel Monitoring Program. Every two years, scientists at the Washington Department of Fish and Wildlife (WDFW) transplant uncontaminated mussels from an aquaculture source on Whidbey Island to various locations in Puget Sound to study pollution levels. Mussels, which are filter feeders, concentrate contaminants from the local marine environment into their tissues. After two to three months at the transplant site, scientists analyze the contaminants in the collected mussel tissues.
The areas where the oxycodone-tainted mussels were sampled are considered highly urbanized and are not near any commercial shellfish beds. “You wouldn’t want to collect (and eat) mussels from these urban bays,” explained PSI’s Andy James, who assisted with the study. The oxycodone was found in amounts thousands of times lower than a therapeutic dose for humans and would not be expected to affect the mussels, which likely don’t metabolize the drug, James said. The findings may raise concerns for fish, however, which are known to respond to opioids. Lab studies show that zebrafish will learn to dose themselves with opioids, and scientists say salmon and other Puget Sound fish might have a similar response.
Scientists typically find many chemical compounds in Puget Sound waters, ranging from pharmaceuticals to illicit drugs such as cocaine, but this is the first time that opioids have been discovered in local shellfish. The contaminants in this case are thought to be passed into Puget Sound through discharge from wastewater treatment plants. Even filtered wastewater can potentially include traces of thousands of chemicals known as contaminants of emerging concern (CECs). Runoff from agriculture and stormwater are also common sources of CECs.
In addition to oxycodone, the mussels also showed high levels of the chemotherapy drug Melphalan, which is a potential carcinogen due to its interactions with DNA. The drug was found at  “levels where we might want to look at biological impacts,” said James. The mussels had ingested amounts of Melphalan relative by weight to a recommended dose for humans.
These Puget Sound mussel monitoring studies occur every two years and are currently funded by WDFW, the state’s Stormwater Action Monitoring program, and various other regional partners. The monitoring is led by Jennifer Lanksbury, of WDFW’s Toxics-focused Biological Observing System (TBiOS), along help from a host of citizen science volunteers from across Puget Sound. PSI’s Andy James worked with TBiOS on the chemical analysis and presented the findings at last month’s Salish Sea Ecosystem Conference.
James and his team at the University of Washington’s Center for Urban Waters in Tacoma are now using high resolution mass spectrometry to look for additional chemical exposures in the mussel tissues and to evaluate potential biological impacts on Puget Sound species.
Read more about mussel monitoring in the Encyclopedia of Puget Sound.
Related story: From Puget Sound to Everest: Water quality studies may aid climbers

Bringing the shellfish back: How Drayton Harbor overcame a legacy of pollution

Prime Drayton Harbor oyster. Photo: Steve Seymour
Prime Drayton Harbor oyster. Photo: Steve Seymour

New in Salish Sea Currents: After a long struggle with pollution, Drayton Harbor has reopened to year-round commercial oyster harvesting for the first time in 22 years. Here’s how the community cleaned up its act, potentially showing the way for shellfish recovery throughout Puget Sound.
Read the full article on the Encyclopedia of Puget Sound. 

Bringing the shellfish back: How Drayton Harbor overcame a legacy of pollution

Prime Drayton Harbor oyster. Photo: Steve Seymour
Prime Drayton Harbor oyster. Photo: Steve Seymour

New in Salish Sea Currents: After a long struggle with pollution, Drayton Harbor has reopened to year-round commercial oyster harvesting for the first time in 22 years. Here’s how the community cleaned up its act, potentially showing the way for shellfish recovery throughout Puget Sound.
Read the full article on the Encyclopedia of Puget Sound. 

Clam hunger: environmental impacts on food and well-being

2013 Swinomish Tribe clam bake. Photo: Copyright Northwest Treaty Tribes https://www.flickr.com/photos/nwifc/9517621153
2013 Swinomish Tribe clam bake. Photo: Copyright Northwest Treaty Tribes https://www.flickr.com/photos/nwifc/9517621153

A story this week in Salish Sea Currents delves into the connection between environmental change and culturally important foods. Writer Sarah DeWeerdt interviewed social scientists at the 2016 Salish Sea Ecosystem Conference about how this affects the spiritual and physical health of Salish Sea tribes and first nations. “The loss of subsistence and cultural identity cannot be estimated,” Joe Schumacker of the Quinault Department of Fisheries told her. In some cases, the yearning to eat culturally important foods can even override health when foods may be hazardous due to toxins from pollution. Read the story on the Encyclopedia of Puget Sound.  

Clam hunger: environmental impacts on food and well-being

2013 Swinomish Tribe clam bake. Photo: Copyright Northwest Treaty Tribes https://www.flickr.com/photos/nwifc/9517621153
2013 Swinomish Tribe clam bake. Photo: Copyright Northwest Treaty Tribes https://www.flickr.com/photos/nwifc/9517621153

A story this week in Salish Sea Currents delves into the connection between environmental change and culturally important foods. Writer Sarah DeWeerdt interviewed social scientists at the 2016 Salish Sea Ecosystem Conference about how this affects the spiritual and physical health of Salish Sea tribes and first nations. “The loss of subsistence and cultural identity cannot be estimated,” Joe Schumacker of the Quinault Department of Fisheries told her. In some cases, the yearning to eat culturally important foods can even override health when foods may be hazardous due to toxins from pollution. Read the story on the Encyclopedia of Puget Sound.