Ocean-acidification ‘refugees’ move to Hawaii
CRAIG WELCH
The Seattle Times
| Tuesday, September 17, 2013, 10:05 a.m.
HILO — It appears at the end of a palm tree-lined drive, not far from piles of hardened black lava: the newest addition to the Northwest’s famed oyster industry.
Half an ocean from Seattle, on a green patch of island below a tropical volcano, a Washington state oyster family built a 20,000-square-foot shellfish hatchery.
Ocean acidification left the Nisbet family no choice.
Carbon dioxide from fossil-fuel emissions had turned seawater in Willapa Bay along Washington’s coast so lethal that slippery young Pacific oysters stopped growing. The same corrosive ocean water got sucked into an Oregon hatchery and routinely killed larvae the family bought as oyster seed.
So the Nisbets became the closest thing the world has seen to ocean-acidification refugees. They took out loans and spent $1 million and moved half their production 3,000 miles away.
“I was afraid for everything we’d built,” Goose Point Oyster Co. founder Dave Nisbet said of the hatchery, which opened last year. “We had to do something.”
Oysters started dying by the billions along the Northwest coast in 2005, and have been struggling ever since. When scientists cautiously linked the deaths to plummeting ocean pH in 2008 and 2009, few outside the West Coast’s $110 million industry believed it.
By the time scientists confirmed it early last year, the region’s several hundred oyster growers had become a global harbinger — the first tangible sign anywhere in the world that ocean acidification already was walloping marine life and hurting people.
Worried oystermen testified before Congress. A few hit the road to speak at science conferences. Washington Gov. Chris Gregoire established a task force of ocean acidification experts, who sought ways to fight this global problem locally.
The eight years of turmoil the Nisbet family endured trying to outrun their corroding tides offered them a unique perch from which to view debate over CO2 emissions.
“I don’t care if you think it’s the fault of humans or not,” Nisbet said. “If you want to keep your head in the sand, that’s up to you. But the rest of us need to get it together because we’re not out of the woods yet on this thing.”
The industry in Willapa Bay, a shallow estuary, and Puget Sound employs about 3,200 people and produces one-quarter of the nation’s oysters.
The Nisbets bought 10 acres of tidelands near Bay Center in 1975 and built their business over decades, one market at a time.
Sometimes Dave Nisbet’s daughter Kathleen, now 27, came along. She sipped a baby bottle and ate cookies while riding the dredge with her father. The Nisbets eventually pieced together 500 acres of tidelands and hired 70 people.
For a long time, business was good — until, overnight, it suddenly wasn’t.
It’s hard to imagine now how far CO2 was from anyone’s mind when the oysters crashed.
In 2005, when no young oysters survived in Willapa Bay at all, farmers blamed the vagaries of nature. After two more years with essentially no reproduction, panic set in. Then things got worse.
By 2008, oysters were dying at Oregon’s Whiskey Creek Hatchery, which draws water directly from the Pacific Ocean. The next year, it struck a Taylor Shellfish hatchery outside Quilcene, which gets its water from Hood Canal. Owners initially suspected a bacteria, But shellfish died even when it wasn’t present.
Each spring, the Nisbets put an order in with Whiskey Creek until the mid-2000s, when that option vanished.
“The hatchery had a long waiting list of customers and no seed, and we had a small window of time to get it into the bay,” Dave Nisbet recalled. “They had nothing.”
Whiskey Creek hatchery closed for weeks at a stretch. Production at Taylor Shellfish was off more than 60 percent. The entire industry was on the brink. Oyster growers from Olympia to Grays Harbor worried that in a few years’ time they would not be able to bring shellfish to market.
Dave Nisbet made frantic calls, but could not find another source.
In 2008, Kathleen Nisbet fretted about the prospect of laying off people her family had employed since she’d been in diapers.
And no one, anywhere, could tell them what was wrong.
Then the oyster growers met the oceanographers.
Dick Feely, with the National Oceanic and Atmospheric Administration, by the early 2000s was noting a dramatic change off the West Coast.
Low pH water naturally occurred hundreds of feet down, where the colder water held more CO2. But that corrosive water was rising swiftly, getting ever closer to the surface where most of the marine life humans care about lived.
In 2007, Feely organized a crew of scientists to measure and track that water from Canada to Mexico.
“What surprised us was we actually saw these very corrosive waters for the very first time get to the surface in Northern California,” he said.
That hadn’t been expected for 50 to 100 years. And that wasn’t the worst of it.
Because of the way the ocean circulates, the corrosive water that surfaces off Washington, California and Oregon is the result of CO2 that entered the sea decades earlier. Even if emissions get halted immediately, West Coast sea chemistry — unlike the oceans at large — would worsen for several decades before plateauing.
It would take 30 to 50 years before the worst of it reached the surface.
Feely published his findings in 2008.
He explained to the oyster farmers that when north winds blew, deep ocean water was drawn right to the beach, which meant this newly corrosive water probably got sucked into the hatchery. That same water also flowed into the Strait of Juan de Fuca and made its way to Hood Canal.
The oyster industry pleaded with Congress, which supplied money for new equipment. Over several years, the hatcheries tested their water using high-tech pH sensors. When the pH was low, baby oysters died within two days. By drawing water only when the pH was normal, shellfish production got back on track.
“They told us it was like turning on headlights on a car — it was so clear what was going on,” Feely said.
It wasn’t until 2012 that Feely and a team from Oregon State University finally showed with certainty that acidification had caused the problem. Early this summer OSU professor George Waldbusser demonstrated precisely how.
The oysters were not dissolving. They were dying because the corrosive water forced the young animals to use too much energy. Acidification had robbed the water of important minerals, so the oysters worked far harder to extract what they needed to build their shells.
Waldbusser still is not entirely sure why acidification has not yet hit other oyster species. It could be because other species, such as the native Olympic, have evolved to be more adaptable to high CO2, or because they rear larvae differently, or because they spawn at a time of year when corrosive water is less common. It could also be that acidification is just not quite bad enough yet to do them harm.
By then, the Nisbets had moved on. They now had their own hatchery, which drew water from a warm, underground, saltwater aquifer. When the tiny bivalves reared there are big enough to produce shells, they are mailed back to Washington and planted in Willapa Bay.
But that doesn’t mean there’s nothing more to fear.
For now, no one else has taken as dramatic a step as the Nisbets. The Northwest industry is getting around the problem. Hatcheries have changed the timing of when they draw in water. Scientists installed ocean monitors that give hatchery owners a few days notice that conditions will be poor for rearing larvae.
Growers are crushing up shells and adding chemicals to the water to make it less corrosive. Shellfish geneticists are working to breed new strains of oysters that are more resistant to low pH water.
But no one thinks any of that will work forever.
“I do not think people understand the seriousness of the problem,” David Stick, manager of the hatchery in Hilo, said. “Ocean acidification is going to be a game-changer. It has the potential to be a real catastrophe.”
At the moment, the problem only strikes oysters at the very early stages of their development, within the first week or so of life.
But how long will that be the case? How would they respond to changes in the food web?
“The algae is changing,” Stick said. “The food source that everything depends on is changing. Will things adapt? We don’t know. We’ve never had to face anything like this before.”