Scientists expect Hawai‘i’s worst coral bleaching ever

In this Thursday 13 August 2015 photo provided by XL Catlin Seaview Survey, a bleached coral reef is shown in Kane‘ohe Bay, O‘ahu. Abnormally warm water caused by a powerful El Niño pattern is heating up the Pacific Ocean to the point that coral reefs in the waters off Hawai‘i have already begun to show signs of coral bleaching. The Seaview Survey team and a crew of scientists were in Kane‘ohe Bay Thursday 10 September to photograph coral as it begins to bleach, hoping to provide a baseline image of the reef before more serious bleaching occurs. The images they create will also be uploaded to Google’s Street View to offer the public a peek inside a normally unseen world. Image courtesy of the Associated Press.

Warmer-than-normal ocean temperatures around Hawai‘i this year will likely lead to the worst coral bleaching the islands have ever seen, scientists said recently. Many corals are only just recovering from last year’s bleaching, which occurs when warm waters prompt coral to expel the algae they rely on for food, said Ruth Gates, the director of the Hawaii Institute of Marine Biology (HIMB). The phenomenon is called bleaching because coral lose their color when they push out algae.

Bleaching makes coral more susceptible to disease and increases the risk they will die. This is a troubling for fish and other species that spawn and live in coral reefs. It’s also a concern for Hawaii’s tourism-dependent economy because many travelers come to the islands to enjoy marine life. Gates compared dead coral reef to a city laid to rubble. “You go from a vibrant, three-dimensional structure teeming with life, teeming with color, to a flat pavement that’s covered with brown or green algae,” she said. “That is a really doom-and-gloom outcome but that is the reality that we face with extremely severe bleaching events.“

HIMB researcher Courtney Couch spent a month in the Northwest Hawaiian Islands. She says the data she collected is alarming. “Just mass mortality! I’ve never seen something that fast happen at that level. It really is a wake-up call,” said Couch. Many of the reefs were 85 to 100 percent dead. Climate experts say it’s all thanks to warmer water temperatures brought on by El Niño.

Read more about it and watch the video reports at KITV4 (autoplays) and KHON2. Read more about it in the Honolulu Star-Advertiser and US News & World Report.