Prickly Seaweed

Acanthophora spicifera
Description:
- Thin branches with many radially symmetrical spines
- Color varies from light yellow, green, brown, to purple
- Grows on hard substrate including rubble
Concern:
- High growth rate
- Spreads by fragmentation
- Able to reproduce sexually
- Introduction unknown; possibly from unintentional hull fouling or ballast water
- High survival rate when exposed to air; able to retain water
Impact:
- Causes shift in ecosystem; what was once coral dominated is now algae dominated with low diversity
- Habitat loss greatly affects recreational and commercial fisheries
- Most prolific and abundant in Hawaii
Distribution:
- Well established on all islands in the main chain