Armed with sample jars, microscopes, and new federal grants, marine scientists are embarking on the most ambitious effort in US history to turn the tide against harmful algae blooms along the nation's coasts.
Sudden explosions in the number of tiny plankton - sometimes visible as "red" or "brown" tides - kill or contaminate fish and shellfish by the millions, undermining ocean-based economies and posing public-health risks.
Around the world, researchers have been trying to curb the spread of harmful blooms using everything from powdered clay to algae-eating clams. Now the US is joining the effort with a $15-million research effort that will utilize such things as satellites and sophisticated computer models. Led by the National Oceanic and Atmospheric Administration (NOAA), the program represents the federal government's first major attempt to tackle a problem that many marine biologists say is getting worse.
The objective is to learn as much as possible about the factors that give rise to harmful algae blooms. Ultimately, researchers hope to develop quick means of identifying, forecasting, and dissipating blooms.
"There's pretty good evidence that blooms are spreading," says Percy Donaghay, a senior marine-research scientist at the University of Rhode Island's Graduate School of Oceanography.
THE scientific assault comes at a time of heightened congressional interest in the ocean's microscopic malefactors. This summer, blooms of a relatively new species of plankton - Pfisteria piscicida - triggered a substantial fish kill in Chesapeake Bay, one of Washington's favorite playgrounds. Tomorrow, the House Subcommittee on Wildlife and Oceans is scheduled to hold hearings on the outbreak.
Marine scientists note that the Chesapeake Bay outbreak has highlighted the significance of a recurring problem that stretches from the Gulf of Maine to the Gulf of Alaska and beyond. In some cases, blooms of harmful algae are increasing. In many others, researchers are discovering additional species that are toxic.
"We're starting to define the boundaries of the problem much better, and they're big boundaries," says Don Anderson, a senior scientist at the Woods Hole Oceanographic Institution in Woods Hole, Mass.
Initially, the new research effort is focusing on three targets: the Gulf of Maine, Florida's Gulf coast, and waters off Long Island, according to Leon Cammen, with NOAA's National Sea Grant Program Office. The multimillion-dollar budget will allow algae researchers to graduate from the skiff-and-waders school of sampling to the use of some of the nation's most sophisticated oceanographic research ships and remote-sensing tools.
The big-budget approach also stems from a growing appreciation of the complexity of the problem. Bilge water in ships carries species from one ocean to another. Currents and surface winds can bring nutrients algae need up from deeper waters, giving them nourishment even in the absence of sewage or agriculture runoff. Overfishing of clams, oysters, and other shellfish, which feed on algae, adds to the problem.
Of the 4,000 known species of algae, only about 6 percent are responsible for harmful blooms. Of these, 2 percent are toxic, says Katherine Richardson of the Danish Institute for Fisheries Research in Denmark.
Yet some of those can play biological hide-and-seek with scientists. Pfisteria, for example, may go through as many as 24 different stages in its lifetime, during which it takes on the appearance of other species.
Even as NOAA's basic research push begins, some marine scientists say more emphasis needs to be placed on finding practical ways to reduce the effects of harmful algae blooms.
"It's a controversial issue," Dr. Anderson acknowledges. "Some of my colleagues say we shouldn't mess with the ocean. Unfortunately, we already have. It's not a pristine environment."
Some attempts to curb the problem have been inadvertent. Someone introduced Chinese duck clams to San Francisco Bay some years ago. By the mid 1980s, water over the clams "was really clarified. The clams were very effective filters, clearing the entire water column every day."
Some of the most aggressive experiments are taking place in Asia, where aquaculture is a major industry and vulnerable to harmful blooms. The Chinese have had "a high degree of success" spreading powdered clay on blooms, according to PeterFranks, a marine biologist at the Scripps Institution of Oceanography in La Jolla, Calif.
Algae binds to the clay, which is non-toxic to fish and sinks to the bottom, carrying the algae with it. This past spring, scientists in South Korea field-tested an approach that uses specially bred organisms to feed on specific algae. The results are not yet in.