Scientists Solve Sea Star Apocalypse Mystery After Twelve Years

On Monday, a group of scientists led by marine ecologist Alyssa-Lois Gehman, identified the culprit behind a mass dying of 5 billion sea stars as the bacteria Vibro pentenicida. This “sea star apocalypse” had started in 2013 on the Pacific Coast of North America and left many sea stars in different stages of death. The sunflower sea star, one of the world’s largest sea stars, has declined nearly 90% in population over the last ten years.

This study involved a series of experiments done by Gehman and her team. They collected sea stars and isolated them. According to the New York Times, if any of the stars were to become sick, they would be placed close to healthy stars to test if the disease would spread to them. The researchers took samples of coelomic fluid, a rough sea star equivalent to blood, from newly infected sea stars and injected it into healthy ones. Using different stars, they also heated up the fluid and inserted it, taking note of the differences in the results of the two groups. While nearly all of the stars injected with non-heated fluid died not long after, none of the heated fluid stars died afterwards. This whittled down the possible culprits significantly.

After further research and experiments, they concluded that V. pentenicida had been the killer of billions of sea stars.

The study that discovered the bacteria that brought forth this destruction was published in Nature Ecology and Evolution, and drew attention from scientists and common man alike. This is mainly because knowing the root of a problem is the only way to even attempt to solve it. “Understanding what led to the loss of the sunflower sea star is a key step in recovering this species and all the benefits that kelp forest ecosystems provide,” says director of ocean science for The Nature Conservancy’s California chapter Jono Wilson. Others, mainly those that study or work with sea stars, are just relieved to know what is killing their beloved animals. “I have been waiting for this for a long time,” remarked Christopher Harley, a marine biologist at the University of British Columbia, in an interview by the New York Times.