LONG BEACH — A microscopic organism that forced state health officials to close razor clam and Dungeness crab seasons last year is still around at varying levels in seawater along the West Coast, but isn’t producing much domoic acid toxin, federal scientists reported this month after wrapping up a research cruise.
A separate study found that a new system for forecasting ocean conditions is providing accurate results. This system, J-SCOPE — short for the Joint Institute for the Study of the Atmosphere and Ocean’s Seasonal Coastal Ocean Prediction of the Ecosystem — doesn’t specifically predict hazardous algal blooms, but highlights some ocean conditions that can lead to them.
This year, “J-SCOPE forecasts 2016 will be a warm year, though not as extreme as 2015,” lead author Samantha Siedlecki, a research scientist at the University of Washington-based joint institute, said in an email. Longer in the future, J-SCOPE looks for the Northeast Pacific to rapidly cool this fall. Cold water is favorable to the traditional start of clam season.
How likely is a second straight year of domoic acid closures?
The NOAA Ocean Acidification Program West Coast Cruise that ended June 7 found “Pseudo-nitzschia cells were abundant in Columbia River plume water over Heceta Bank” off the Oregon coast. This is the algae that sometimes produce harmful concentrations of domoic acid, which lead to shellfish season closures. However, the exact algal species found in Columbia water were different than those identified farther south off Monterey Bay, California. The Columbia algae contained a measurable amount of domoic acid, but less than in California waters.
Overall, the area offshore of the Columbia is a region of high productivity in surface waters, NOAA noted. The cruise found “significantly more” desirable cold-water zooplankton species in Columbia water compared to California.
The cruise found some Columbia River waters near the bottom have very low oxygen, creating what is often called a “dead zone.”
Off the Washington coast, late-spring surface water temperatures ranged from 12 to 14 degrees C, or about 53.6 to 57.2 degrees F.
“Temperatures were slightly higher than the average to the south and slightly lower than average in the near-coastal waters to the north,” NOAA said.
“Crab larvae were highly abundant in the near-shore surface net tows,” along the Washington coast, NOAA said.
On the marine toxin issue, NOAA said “Pseudo-nitzschia species were observed in the majority of samples from the Washington coast” and that the highest concentrations during the cruise were found in the Juan de Fuca eddy. Past research has suggested that algae from this eddy — basically a swirling undersea river that flows out of Puget Sound and the Salish Sea — might be the source of toxins that spread south along the coast.
“Domoic acid concentrations at the eddy site were low however, indicating the species present at the time were not producing high amounts of the neurotoxin,” NOAA said.
Wrapping up their results, NOAA researchers said, “From a scientific perspective, the cruise demonstrated how natural variability, climate change and ocean acidification combine to effect large-scale chemical and biological changes over the various sub-regions we studied. It also demonstrated the great extent to which the Columbia River, Juan de Fuca eddy, and Fraser River influence the local chemistry and biology of the sub-regions.”
University of Washington News and Information reports J-SCOPE has similarities with seasonal weather forecasts — whether to expect an El Niño ski season, or an unusually warm summer. Climate models can now being adapted to make seasonal forecasts for the region’s coastal waters.
This would help tell if it’s going to be a great year for sardines or a poor crab season. A paper evaluating the forecast’s performance was published in June in the interdisciplinary, open-access journal Nature: Scientific Reports.
“Ocean forecasting is a growing field, and the Pacific Northwest coast is a particularly good place to use this approach,” according to lead author Siedlecki.
Seasonal forecasts for water oxygen, temperature, chlorophyll and pH (acidity) along the coast of Washington, Oregon, Puget Sound and Canada’s Vancouver Island have been posted for the past three years on the UW-based Northwest Association of Networked Ocean Observing Systems website: tinyurl.com/J-SCOPE-forecast. This site now offers a comparison between the forecast values and the long-term average, and the probability for different scenarios.
“The forecasts have been evolving over the years,” Siedlecki said. “We’re trying now to put the forecast in context — is this better or worse than in recent years?”
The tool does especially well at the beginning of the spring upwelling season and matches observations most closely below the surface. This is good, Siedlecki said, because that’s where measurements are scarce.
“Our tool has more skill in the subsurface, for things like bottom temperature and bottom oxygen,” she said. “That’s exciting because it can inform us where and when the low-oxygen and corrosive conditions that can be stressful to marine life would likely develop.”
The fall season is more storm-driven, she said, and consequently difficult to predict.
The goal is to eventually combine the ocean forecasts with fisheries management, so that decisions surrounding quotas could take into account the conditions for the species’ habitat during the coming season.
A sardine forecast was recently added and was the focus of a separate NOAA-led paper published this winter in Fisheries Oceanography. That forecast shows moderate skill in predicting sardine populations five or more months out.
The group now has funding from NOAA’s Northwest Fisheries Science Center to work on forecasts for hake, also known as Pacific whiting, since the widely fished species lives below the surface and seems sensitive to oxygen concentrations. The researchers are interested in developing similar forecasts for salmon and other species. Hake are an important catch for Columbia River-based fishermen.
Forecast values include pH and aragonite, a calcium-containing mineral that marine animals use to harden their shells, so the tool can also help predict which months will have good conditions for growing shellfish.
“The oyster industry has already been treating the intake seawater coming into the hatcheries,” Siedlecki said. “If our forecasts can help the growers identify times of year that would be most suitable to set up juvenile oysters out in the open ocean, that would potentially help them get a leg up on changing conditions.”
For this summer, the outlook may be good news for ocean swimmers who like warm water and bottom-dwelling fish that sometimes struggle to breathe in the late summer or early fall.
“The current forecast is showing weak upwelling, warmer temperatures and higher oxygen than we’ve had in the past, so a bit of a relief in some ways for the ecosystem,” Siedlecki said.
“Chlorophyll is forecasted to be low in the north and higher than average chlorophyll in some parts of southern Oregon, and in regions associated with the Juan de Fuca eddy. Overall J-SCOPE forecasts higher oxygen concentrations (less hypoxia, occurring later) than in average years. Ocean conditions are forecast to be suitable for sardine, though depressed stock abundance may mean that fewer sardine migrate to Pacific Northwest and British Columbia waters in the summer,” Siedlecki said in an email.
Affecting all this will be the North Pacific’s likely transition to ENSO-neutral conditions by early summer, with an increasing chance of La Niña during the second half of the year, she said.
— Hannah Hickey of UW News and Information contributed to this report.