A foreign and invasive algae has threatened local marine life along the coast of Newport Beach for months before government officials removed it.

City, state, and federal officials began removing the algae just two weeks ago after a local diver first discovered the algae invading local waters in March.

In May, the City of Newport Beach declared a state of emergency over the algae’s potential harm for coastal habitat.

It only took a matter of days to remove the harmful species.

But it may take months, even years, to ensure the algae — known scientifically as Caulerpa Prolifera — and its threat to local ecosystems is completely gone, officials said last Tuesday, as the area is still under close watch. 

In turn, Newport Beach City Council members voted in last week’s meeting to continue the algae state of emergency.

Caulerpa of other types have threatened marine life along the California coast before. 

Thus, a collection of different local, state and federal agencies — coalesced under the Southern California Caulerpa Action Team — have taken the lead in trying to resolve the issue in Newport.

The team spent months deliberating, securing funding and surveying the area, before the algae clean-up process began July 7 at a small public beach called China Cove. There were several patches of Caulerpa in the harbor that totalled about 1,000 square feet, according to biologist Robert Mooney with Marine Taxonomic Services who worked on the project.

It took slightly longer than the 4-5 days expected to remove the algae, but the signs and equipment are vanishing as the project concludes, according to Chris Miller the harbor resources manager for Newport Beach.

However, the algae has not been completely eradicated. 

“There will certainly be follow-up work … We won’t be able to declare that eradicated for a very long time after we’ve surveyed and surveyed and surveyed,” Miller said. 

This invasive species they’re weeding out can spread from just tiny fragments and may take years to completely get rid of. Although the algae is considered removed, the harbor will have to be tested for years to make sure the algae doesn’t return, said Mooney.

Caulerpa prolifera is a native species to Florida and other tropical regions. This is the first time it has been cited in California.

A related species, however, was found in San Diego and Huntington Beach in 2000. Dubbed “killer algae” the threat prompted a serious and strategic eradication project. It took six years and $7 million. The Newport Beach infestation was smaller in scope, said Mooney. Once those  projects were complete, critically important coastal plants and habitats recovered. 

When risk modeling for Caulerpa invasions was conducted in 2006, China Cove placed in the highest risk category, according to the California Fish and Wildlife website

The Process

The divers from the California Department of Fish and Wildlife swam back and forth on the seafloor to assess the scope of the outbreak in April. Swimming buoys and signs were put up near the entrances to the beach to keep people away.

Plant material and sediment was deposited in large bins that on the beach. Credit: JILLIE HEROLD, Voice of OC

There was a slow start when the removal process began, but the biologists were able to remove the algae without any huge hiccups, Miller said. The machines they used sucked up the seawater into containers to filter algae before returning the clean water back to the ocean. 

The biologists and divers were hired by the California State Water Resources Control Board, which provided about $300,000 for removal and some surveying, Miller said. 

Coincidentally around the same time the Caulerpa was found, a $4 million dredging project by the U.S. Army Corps of Engineers was scheduled to begin at the entrance of the harbor where the algae was found. 

Marine biologists conducted surveys and confirmed there was no Caulerpa there, allowing the dredging project to proceed.

About Caulerpa

Caulerpa can be harmful because it grows quickly, at the expense of native seaweeds and seagrasses. It can take over and choke out critical eelgrass beds, which have a variety of important functions like providing food, oxygen and shelter for marine animals; filtering pollution; and reducing coastal erosion, according to an article by the National Oceanic and Atmospheric Administration’s office of Fisheries. 

Some types of Caulerpa secrete a toxin that mollusks, herbivorous fish and sea urchins avoid. 

In tropical waters, herbivores have immunity to these toxic compounds, but there are no known predators on the California coast.

Although potentially harmful to non-native marine ecosystems, there is no danger to humans. 

People visited China Cove during the removal process and were made aware of the hazard through signage and swimming buoys. Credit: JILLIE HEROLD, Voice of OC

Still, the public is advised to avoid contact with the algae since it can spread from tiny fragments, according to a profile of the species by the California Fish and Wildlife. 

It is believed that the Caulerpa invaded Newport Harbor through someone cleaning out their fish tank. 

“Coming from an aquarium is very plausible and seems to be the source, although it’s impossible to say that with 100% confidence,” Miller said.

Miller says he won’t request another extension to continue the state of emergency in Newport Beach after the 60 days are up. The current extension was approved out of an abundance of caution.

The Department of Fish and Wildlife asks people to report online if they have seen the invasive algae. 

In the coming months, the Southern California Caulerpa Action Team will continue surveying Newport Harbor and surrounding areas.

“A one centimeter fragment can grow and we know that the alga had already fragmented substantially from when we were out there looking at it. So we picked up numerous small fragments as well during this whole effort. It’s going to be very important to keep searching moving forward,” Mooney said.

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