An Invasive Species: Caulerpa prolifera

In September 2023, a species of algae was discovered in San Diego Bay that can cause damage to local marine life. Caulerpa prolifera, a species native to Florida and other subtropical locations, is fast growing and can take out native seaweeds and harms life through habitat loss. It has invaded seagrass and soft bottom habitats in different habitats, pointing to how dangerous it can be for San Diego Bay.

Not only does it rapidly grow and spread, it is also inedible to herbivorous marine life. Caulerpa prolifera, if left unchecked, can cause a wide range of issues, running from diminishing marine habitats to slowing economic industries such as fisheries and tourism. These algae are so dangerous that there is a Southern California Cailerpa Action Team (SCCAT). They have come up with solutions to combat the spread and permanently remove them from San Diego Bay. These include controlling the infestation site, sending divers to conduct surveys and locate potential outbreaks, and sealing the Caulerpa prolifera with barriers to exclude it from light, oxygen, and circulation.

What can you do?

The most important action is to make sure you don't dump aquarium water into the drains, as that is how it is originally thought to have come into the bay. These algae can be recognized from the tiniest fragments, making it easy to regrow even if they are all removed beforehand. Below is an attached flyer from the California Department of Fish and Wildlife that highlights how to properly disprove Caulerpa.

California Department of Fish and Wildlife Informational flyer (PDF)