Scientists Say a Plague of Sea Stars is Devastating Pacific Coral ReefsNewsroom
Killer rising ocean temperatures, crazy bleaching events and oil slicks comprised of sunscreen from sunbathers that denude them are just some of the problems plaguing the world’s coral reefs today. Now they are under attack by hordes of thorny sea creatures.
According to a news report posted this week by The Washington Post, this is what some scientists are calling an explosion of voracious crown-of-thorns sea stars in Maldives that are eating coral reefs with mouths in their stomachs. For some reason — no one quite knows what — their numbers have grown out of control. Where once divers would see one or two eating coral across about a mile, they’re now seeing 100. And a single sea star can produce 50 million eggs per year, scientists said.
“Their population is exploding in numbers that haven’t really been seen in the Maldives before,” said Alexandra Dempsey, a coral ecologist for the Khaled bin Sultan Living Oceans Foundation. “They can be clumped in an area with 60 to 80 animals within 20 meters, or four or five animals on one patch of coral. We’ve swam distances of 1,500 meters to collect 100 animals.”
he result is a list of major headaches for humans and nature. For Maldives, which took in nearly a billion tourism dollars in 2010, it threatens the economy because coral lures about 800,000 vacationers per year. For coral, it’s the ultimate sacrifice, say scientists who’ve reported a killing field of bleached reefs that stretches for miles. For fish and other animals — sponges, eels, reef sharks, angelfish, it means the loss of their homes, breeding areas and nurseries.
“Once the fish lose their home and they have nowhere to live,” Dempsey said, “they’re going to start to die off, affecting the food chain and larger fish.”
An organized harvest launched by the foundation Oct. 14 to Nov. 3 netted more than 7,000 animals. “We are … saving hundreds of corals for each starfish that we take off the reef,” said Andrew Bruckner, the chief scientist for the foundation.
Sea stars that climb on coral and leave them dead aren’t the only worry. The gigantic El Niño stretching across the Pacific Ocean is warming waters to temperatures coral can’t stand. When it reaches a certain threshold, basically getting too hot, they lose their ability to photosynthesize, break down, die and turn bleach white.
For more of the report, go to The Washington Post.