Warm waters and infectious diseases have been identified as the causes of sunflower star death along the Pacific Ocean coast, says newly released study.
Sea Star Sunflowers are among the largest starfish in the world and come in different bright colors, including purple and orange. Some of them grow to more than one meter and are so fast that they "literally pass through the seaside landscape," said Joseph Gaydos, lead author of the study.
"But when this disease happens, it's like a zombie apocalypse," said Gaydos, at SeaDoc at Davis University in California.
"He may have 24 shoulders, and suddenly he passes by, and the weapons just fall, and then suddenly it seems that the whole body melts."
So what used to be a "big, beautiful sea star" and weighs about five pounds, recalls in a few days a pile of calcified parts.
"It is a really ugly and fast disease for these sunflower stars."
In 2013, scientists began to record a decline in species populations between 80 and 100 percent in deep and shallow waters from Alaska and B.C. directly to California. Information on the population was collected by divers and deep-sea trawls.
Sunflowers of the sea star are found in the waters from hundreds of meters to three meters.
Diego Montecino-Latorre, co-author of the study, as well as from the University of California, Davis, said the researchers found a link between increased water temperatures and fewer marine stars.
Gaydos said the rise in water temperature was not the same in all areas.
Oceans are not "like a bath" with consistent temperatures across the range, he said, adding that some areas in California recorded an increase of about 4 ° C, while locations in Washington reported an increase of 2.5 ° C.
One of the theories proposed by scientists is that the rise in temperature causes the sea stars to be more prone to the disease that has already been present, especially because the sea stars do not have a complex immune system, he said.
Gaydos said that dying-calling is awakening.
"It's hard to see what's happening in the ocean, but we have to pay attention because it happened in a very short time," he said. "If you want to almost disappear, it's not good."
Hina Alam, Canadian Press
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