Researchers have recently unraveled a marine mystery: billions of sea stars are melting away along the West Coast, and the cause is likely a strain of bacteria, not a virus as previously thought.
This alarming phenomenon, called sea star wasting disease, has been harming sea stars since 2013. It’s pushing some species, like the sunflower sea star, toward extinction. For four years, scientists studied this issue, using DNA sequencing to analyze microbes in both sick and healthy sea stars. They discovered high levels of a bacteria called Vibrio pectenicida, which also causes cholera and has harmed coral and shellfish populations.
Dr. Alyssa Gehman, a senior study author from the Hakai Institute and the University of British Columbia (UBC), expressed excitement upon this finding, saying, “We all had chills. We thought, That’s it. We have it.” This breakthrough, published in Nature Ecology and Evolution, could change the way we address marine health issues.
Sunflower sea stars, which can grow over a meter wide, are severely affected. In many areas, they are functionally extinct, and their significant decline—often by more than 87%—has devastated marine ecosystems. According to a recent study, losing these stars means exploding sea urchin populations, which gobble up kelp. Kelp forests are vital, providing habitats, supporting the fishing economy, and even protecting coastlines.
Melanie Prentice, another lead researcher, noted, “Losing a sea star goes far beyond the loss of that single species.” When sea stars disappear, the entire ecological balance shifts.
Tracking down the cause of wasting disease has been challenging. The disease begins with visible lesions and, within two weeks, destroys the sea star’s tissue, turning it into goo. This made it tricky for scientists to identify what was wrong. However, their investigation led them to V. pectenicida, specifically strain FHCF-3.
To confirm their findings, researchers infected healthy sea stars with the bacteria and saw nearly all succumb to the ailment. This evidence points to bacteria as the main culprit.
Moving forward, researchers aim to understand what drives this disease and how to combat it. Jono Wilson from The Nature Conservancy emphasized the need to comprehend the causes of the sunflower sea star’s decline to aid recovery efforts. It’s clear that the health of one species can ripple through an entire ecosystem.
While the journey to fully understand sea star wasting disease continues, this finding is an essential step toward safeguarding both sea stars and the vital ecosystems they support.
For more enlightening marine research, you might explore reputable sources like The Nature Conservancy’s report on marine health and species recovery.
