Move over, killer whales. Scientists have discovered a new underwater species that's wreaking havoc on what's known as the most remote and protected ocean environments on Earth: killer seaweed.
Researchers in Hawaii say the "aggressive" form of seaweed is spreading near the Northwestern Hawaiian Islands faster than any other species of underwater plant they've seen -- and it's killing huge patches of coral on the state's formerly pristine reefs. "This is a highly destructive seaweed with the potential to overgrow entire reefs," says biologist Heather Spalding. "We need to figure out where it's currently found, and what we can do to manage it."
Researchers say the killer seaweed breaks apart easily and rolls across the ocean floor like tumbleweed. After settling in areas of thick vegetation, the broken segments spread and quickly beat out coral for space, sunlight and nutrients, they say. "It is a matter of concern whenever you see an ecosystem start to display symptoms like this," says University of Queensland Professor Peter Mumby.