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Governor Signs Bill to Ban Invasive Caulerpa Algae That Threatens Coastal Ecosystems

For immediate release:
  • Orange County Coastkeeper and California Coastkeeper Alliance worked with Assemblymember Cottie Petrie-Norris to introduce Assembly Bill 655, which was signed into law by Governor Newsom on July 27.
  • AB 655 bans all sale and transportation of saltwater algae of the Caulerpa genus to reduce the chance of further invasions of our coastal environment.
  • Caulerpa prolifera was discovered in Newport Bay in 2021 and has yet to be fully eradicated. Caulerpa taxifolia invaded the Southern California coast in the early 2000s and cost millions to eradicate.

On Thursday, July 27, Governor Newsom signed Assembly Bill 655 into law, enacting a statewide ban on the invasive Caulerpa genus of algae. The bill was introduced by Assemblywoman Cottie Petrie-Norris (D-Irvine) and sponsored by Orange County Coastkeeper and California Coastkeeper Alliance.

Under AB 655, Californians are prohibited from selling, possessing, importing, transporting, transferring, releasing alive in the state, or giving away without consideration all saltwater algae of the genus Caulerpa, except that in possession for bona fide scientific research.

Caulerpa Threatens Our Coastal Environment
The Caulerpa genus is popular in the aquarium trade due to its hardy nature, fast growth rate, and attractive green color. It is native to the warm, tropical waters of Florida and the Caribbean. However, it can easily adapt to and thrive in California’s colder waters.

Caulerpa has been shown to rapidly outcompete California native plants in areas it has invaded, displacing wildlife and altering the ecosystem around it. A single blade can sprout a whole new plant, making it hard to remove without constant monitoring. It also contains toxins that repel most fish outside its native range.

Past and Current Caulerpa Invasions
An established patch of Caulerpa prolifera, a species within the Caulerpa genus, was identified in Newport Bay’s China Cove in early 2021. The Southern California Caulerpa Action Team (SCCAT), a group of various agencies and stakeholders, has since been surveying for and removing C. prolifera plants throughout the Bay. SCCAT’s methods have been effective; however, limited funding has made total eradication impossible thus far.

A close cousin of C. prolifera, Caulerpa taxifolia, was discovered in California in 2000 and took almost seven years and $7 million to eradicate. At that time, it did severe damage to native eelgrass habitat.

Protecting Our Coast for More Invasions
Illegal dumping of aquarium water is the most likely source of both the C. taxifolia invasion of the early 2000s and the current C. prolifera invasion in Newport Bay.

In 2001, California banned the transportation and sale of C. taxifolia and several other Caulerpa species. However, C. prolifera and the rest of the genus remained legal to sell and trade. The statewide ban will go into effect on January 1, 2024.

“As long as Caulerpa is sold and transported along the coast, there is always a chance of reintroduction and another long and costly eradication effort,” said Garry Brown, Founder and President of Orange County Coastkeeper. “The statewide ban on Caulerpa is a crucial step towards safeguarding our delicate coast from further invasions. This is a big win for our marine ecosystems, and it wouldn’t have been possible without the help of California Coastkeeper Alliance and Assemblywoman Cottie Petrie-Norris.”

“We want to thank Governor Newsom for signing AB 655 into law,” said Sean Bothwell, Executive Director of California Coastkeeper Alliance. “Invasive species are a pervasive problem in California, but banning Caulerpa is a simple fix to a very serious and expensive problem.”

“I am proud to partner with California Coastkeeper Alliance and Orange County Coastkeeper to advance this bill into law to ban all species of Caulerpa algae and prevent the irresponsible dumping of this highly invasive species into our coastal waterways,” said Assemblywoman Cottie Petrie-Norris (D-Irvine). “AB 655 allows the state to protect our coastal waters from invasive Caulerpa algae by creating safeguards for costly infestations that pose a serious risk to our coastal ecosystems and native marine life.”