‘Killer Algae’ Invades O.C.

Marine experts are requesting $100,000 in emergency state funds to fight the highly invasive seaweed known as “killer algae” found in a saltwater pond alongside Huntington Harbour.

The discovery marks only the second time that the bright-green seaweed has been found on the west coasts of North and South America. Government officials in July announced the first occurrence of Caulerpa taxifolia in Carlsbad’s Agua Hedionda Lagoon, 35 miles north of San Diego.

Discovery of the algae in California is alarming marine biologists, who fear it will spread quickly, killing kelp and other native sea vegetation and threatening commercial fisheries. The accidental 1984 release of killer algae into the Mediterranean Sea has harmed tourism and destroyed recreational diving across a large area there.

Now the algae has been found in a three-acre pond fed by seawater at the north end of Huntington Harbour. The pond, one of two known as the Seagate Lagoons, contains hundreds of patches of the algae, said Rachel Woodfield, a marine biologist with Merkel & Associates, a San Diego-based biological consulting firm. Woodfield is overseeing efforts to kill the algae in both Carlsbad and Huntington Harbour.

“You really wouldn’t know it was a big deal if you just looked at it,” Woodfield said. “Now that I know what it can do, it scares the tar out of me.”

The Huntington Harbour algae was spotted by a local professor several months ago. He contacted authorities during the summer after seeing publicity about the Carlsbad discovery and recognizing similarities with the pond plant, officials said.

“He called it in. That’s what we’re really looking for,” said Greig B. Peters, senior environmental specialist at the San Diego Regional Water Quality Control Board.

Both algae outbreaks probably were caused by people emptying their aquariums, unaware of the consequences, Peters and others said. The seaweed is a popular plant for saltwater aquariums because of the brilliance of its virtually fluorescent green foliage.

Although the algae is not harmful to people, it kills eelgrass meadows and other plants that are crucial to the marine food web, endangering many fish and invertebrate species.

Scientists familiar with its disastrous effects in the Mediterranean petitioned the federal government in 1998 to forbid its importation, and it was named a prohibited species in 1999 under the Federal Noxious Weed Act.

Testing has found strong similarities between the Carlsbad and Huntington Harbour algae, Peters said.

“They are essentially identical, and they are almost identical to the Mediterranean strain,” he said.

At the Carlsbad lagoon, workers have covered the plants and injected chlorine to kill them. Today, the algae above the sand line is bleached white and dead, but experts worry the roots could prove harder to kill. Just one millimeter of root is believed capable of sprouting a whole new plant, Peters said.

The cost of the Carlsbad control work could reach $2 million, said a spokesman at the California Water Resources Control Board in Sacramento. Just this week, the Santa Ana regional water board submitted its request for $100,000 to start work on the Huntington Harbour ponds.

Experts want to eradicate the killer algae before it creeps into fragile habitat such as the Seal Beach National Wildlife Refuge just north of Huntington Harbour--or into the bustling ports of Long Beach and Los Angeles, where ships could carry it up and down the coast.

People who see killer algae while snorkeling or diving should contact the San Diego Regional Water Quality Control Board’s Caulerpa Action Team at (858) 467-2952.

More information on the algae is available on the Internet at https://swr.nmfs.noaa.gov/hcd/CAULERPA.htm or by contacting the action team by e-mail at caulerpa@rb9.swrcb.ca.gov.