OREGON STATE UNIVERSITY

Harmful algal blooms on rise globally, but Oregon monitoring at risk

07/09/2010

CORVALLIS, Ore. – Scientists are moving closer to being able to predict when blooms of phytoplankton will turn toxic and prompt closures of shellfish harvesting along the coast to protect the public from domoic acid and other health threats.

But the funding that has supported a unique collaborative research and monitoring effort among several agencies will soon run out, leaving future monitoring of “harmful algal blooms” in Oregon in jeopardy.

“We’re moving closer toward having a predictive model, but we won’t get there until we have more people on the ground – counting phytoplankton, doing the toxin analysis, and monitoring the clams and mussels themselves,” said Angelicque “Angel” White, a biological oceanographer at Oregon State University and a principal investigator in a five-year study of harmful algal blooms.

“The goal is to be able to identify potential risks earlier – before they actually show up in the shellfish,” she added.

Razor clam harvesting was closed last week in Oregon from Bandon to Tillamook because of high levels of domoic acid – which White and her colleagues anticipated based on cell counts of harmful algal blooms.

At least parts of the Oregon coast are closed to shellfish harvesting almost every year, White said, and incidents of harmful algal blooms are on the rise globally. “In addition to being a health concern, it’s an economic factor as well,” White said. “These closures can cost coastal communities millions of dollars of lost income.”

A closure of razor clam harvests in 2003 of beaches in Clatsop County alone cost local communities an estimated $4.8 million in lost revenue.

Phytoplankton blooms are a normal ocean process, critical to maintaining the productive marine food web off the Pacific Northwest coast. Spring and summer winds bring up cold, deep water that is nutrient-rich to the ocean surface in a process called “upwelling.” When that water is exposed to sunlight, it creates blooms of phytoplankton. These tiny plants are a source of food for zooplankton and other marine creatures, which in turn are feasted upon by larger animals.

But certain species of phytoplankton have the ability to produce toxins that can be harmful to humans. One called Pseudo-nitzschia produces domoic acid, which bio-accumulates in the tissues of razor clams and mussels and can cause illness, and even death in humans. Another species, Alexandrium, produces saxitoxin, which can lead to paralytic shellfish poisoning if ingested.

The Oregon Department of Fish and Wildlife and the Oregon Department of Agriculture test clams, mussels and other shellfish for domoic acid accumulation. Scientists from OSU and the University of Oregon work with ODFW on monitoring the phytoplankton blooms and checking for toxicity. And the National Oceanic and Atmospheric Administration lab at OSU’s Hatfield Marine Science Center contributes offshore phytoplankton sampling. Their work is funded through NOAA’s national “Monitoring and Event Response for Harmful Algal Bloom,” or MERHAB program.

“We’ve made it work,” said Bill Peterson, a biologist with the NOAA lab in Newport. “The five years of NOAA (MERHAB) funding allowed us to ramp up the monitoring of shellfish and plankton to a workable level, but Oregon still lags behind California and Washington when it comes to monitoring harmful algal blooms. They’re a lot farther ahead on figuring these things out.”

The collaborators’ NOAA funding, a total of $2.3 million in grants, will run out in another 18 months and anticipated state funding for the successful pilot program remains uncertain.

In their remaining time, the scientists will try to learn more about what causes certain phytoplankton blooms to become toxic, how long it takes for that toxicity to build up in the shellfish and what role ocean conditions like temperature, salinity and acidification may play.

“Phytoplankton toxicity is highly variable,” said Matthew Hunter, the ODFW shellfish and estuary project leader. “It can accumulate in razor clams in as little as a week’s time, or it can take several weeks – and we don’t yet know why there’s a difference. At the same time, the toxic phytoplankton may comprise only about 5 percent of the overall plankton biomass at any one time.

“There’s a lot still to discover,” he added, “but hopefully we can learn enough to create some kind of forecasting model that will change our sampling time frame and provide more warning when domoic acid, for example, may be becoming a problem.”

Marc Suddleson, who manages NOAA’s MERHAB program, said the investment in this academic/state/federal collaboration is designed to act as seed funding until local support can continue the effort.

“Hopefully, Oregon will adopt this proven pilot monitoring program and benefit from the early warning of toxic algal events it provides, helping to reduce their threat to public health and to safeguard valuable state recreational shellfisheries,” Suddleson said. “This program can help Oregon and NOAA advance mutual interests in improving harmful algal bloom monitoring and prediction for the entire Pacific coast.”

White agrees that Oregon needs to create and fund a formal monitoring effort that looks at toxin levels in both phytoplankton and shellfish. A network of volunteers could be utilized to gather water samples, she pointed out, but “our collaboration has demonstrated that a trained technician to identify toxicity is vital.”

“Oregon is bringing up the rear along the West Coast when it comes to addressing harmful algal blooms,” White said. “Considering the human health and economic issues associated with domoic acid and paralytic shellfish poisoning, and the fact that these toxic blooms are on the rise, I’m not sure that’s a place we want to be.”