Invasive Seaweeds and Hull Fouling Species

Caulerpa taxifolia - Visit ITIS for full scientific classification. 

Caulerpa taxifolia. © 2005 Regents, University of California.

• Fast-growing, bright green feather-like fronds, 3-5 inches tall, arising from horizontal stems (stolons).
• Used as a decorative saltwater aquarium plant.
• Occurs as both a native and an invasive strain.
• Easily confused with other species of Caulerpa.

• Found on rocky, sandy and muddy bottoms in shallow lagoons, or at deeper depths.

• Broadly distributed in tropical seas.
• Invasive aquarium strain spreads when released in the sea.
• Can grow from small fragments transported by boat anchors and fishing gear.
• Now found in the Mediterranean Sea and Australia.
• Introduced to two small lagoons in California in 2000 and removed with great effort and expense.
• Now illegal to possess, sell, or transport in California.

• Sexual reproduction observed in the native strain, but not in the invasive aquarium strain, which reproduces through fragmentation.

• Grows and spreads rapidly, forming dense mats.
• Outcompetes native species for space and light.
• Contains toxic substances that make it distasteful to animals that eat seaweeds.

For references by category and links to other useful AIS sites see our LEARN MORE page.