Hawaii's Worst Coral Bleaching Ever Could Happen This Fall
El Niño and other factors are creating conditions that could critically stress, and ultimately kill Hawaii’s treasured coral reefs.
A school of manini fish pass over a coral reef at Hanauma Bay in Honolulu on Jan. 15, 2005.
Donald Miralle / Getty Images
Corals — which famously form reefs in Hawaii and other coasts around the world — feed on algae. The algae gives coral its distinctive color.
Sometimes, however, corals expel that algae, turning them white in a process called coral bleaching. That’s what is going on right now in Hawaii, and experts fear this year’s bleaching event could be the state’s worst ever.
Ruth Gates, director of the Hawaii Institute of Marine Biology, told BuzzFeed News Saturday bleaching has already begun. On a recent trip out to see corals, about 10% were white, she said.
Bleaching doesn’t automatically kill corals, but it does leave them more stressed, more susceptible to disease, and ultimately more likely to die.
Worse still, many of the corals around Hawaii are still recovering from a major bleaching event that happened last year, Gates said, when as much as 70% went white. Much of it recovered, but of the most severely affected areas, between 85% and 100% have since died, according to the Department of Land and Natural Resources.
“The problem now is that we have the second bleaching event coming so quickly on the heels of last year,” Gates said.
As a result, Gates called this year’s conditions “unprecedented” and “very worrying.”
“I’m struggling to find an example where we’ve had two back to back bleaching events,” Gates added. “This double whammy is not really common.”
A partially bleached coral in Kaneohe, Hawaii, as seen on Thursday.
Dan Dennison / AP
Henry Lau, a National Weather Service forecaster in Maui, told BuzzFeed News the water temperature around Hawaii at this time of year is normally about 77 degrees. But this year, the temperature is about 82 degrees. And the warm water could stick around for months.
“We do not expect to see sea surface temperatures really go down until early next year,” Lau added.
That could spell disaster for Hawaii’s corals because high water temperatures are what prompt bleaching events.
Gates said the high temperatures have arrived earlier this year than normal.
“At this time it’s very early in the year and we are way ahead of the time in which bleaching should be happening,” Gates said.
So far this year, scientists already have reports of bleaching near Oahu, Maui, and the Big Island, the Associated Press reported. Moreover, a mile and a half of coral reef near a remote part of Hawaii’s northeastern corner is essentially dead, a researcher told the AP. The coral apparently died from last year’s bleaching event.