SAN DIEGO, CA - AUGUST 07: Beachgoers gather near dying kelp near Scripps Pier on August 7, 2018 in San Diego, California. A researcher said the area has seen above average amounts of dying patties of kelp recently which is attributed to warmer ocean temperatures. The sea surface temperature at Scripps Pier was measured at an all-time high of 78.8 degrees on August 3, the warmest since record keeping began at the pier 102 years ago. (Photo by Mario Tama/Getty Images)

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.


Aggressive seaweed threatens Hawaii's remote reefs, could spread

Researchers say a recently discovered species of seaweed is killing large patches of coral on once-pristine reefs and is rapidly spreading across one of the most remote and protected ocean environments on Earth.