Caulerpa: A Living Pollutant

March 6th, 2023

Two hundred square meters of sea floor off the coast of Newport Bay have been infested with the green algae Caulerpa prolifera. Like other species of Caulerpa, California’s Department of Fish and Wildlife has determined that this algae is a serious invasive species. What makes Caulerpa such an exceptionally dangerous invasive is its ability to grow incredibly fast, out-compete native species, and reproduce from even the smallest fragment. As a result, anything less than total eradication is insufficient to deal with this invasive alga.

What’s worse, the outbreak in Newport Bay isn’t the first time California has had to deal with Caulerpa. In 2000, there were two outbreaks of Caulerpa taxifolia in Southern California lagoons. Even after the state took immediate actions to eradicate those outbreaks, it still took six years and seven million dollars to remove the Caulerpa and restore our important native eelgrass ecosystems. The only silver lining is that, in 2001, California tried to pass a bill to permanently ban all species of Caulerpa from the state. However, Caulerpa is used in saltwater aquariums, and pushback from the aquarium lobby shriveled the bill from a total ban into a partial ban. When the bill finally passed the legislature, it only banned nine species of Caulerpa. One of the species the aquarium lobby specifically wanted exempted was Caulerpa profilera, the invasive species currently expanding its foothold in Newport Bay. 

California Coastkeeper Alliance with Orange County Coastkeeper, have worked with Assemblymember Petrie-Norris to introduce Assembly Bill 655, to completely ban all species of Caulerpa from California. As history has demonstrated, a partial ban was only partially effective. Without a total ban, other infestations of Caulerpa are all but guaranteed to continue; all it takes is a single piece of algae dumped into the ocean from a saltwater aquarium. This bill will work to protect our coastal ecosystems and native eelgrasses from a serious invasive genus of algae.

Stay informed of our legislative work and our efforts to protect California’s waters by subscribing to California Coastkeeper Alliance’s monthly newsletter, becoming a lifetime member, or following us on social media: @CA_Waterkeepers

Categories: Happening Now, Legislation