Researchers Crack Code of Devastating Sea Star Wasting Disease

In a major breakthrough, researchers have cracked the code of a deadly disease that has decimated sea star populations along the Pacific coast of North America for over a decade. The team, led by scientists in British Columbia, has identified the Vibrio pectenicida bacteria as the clear cause of the sea star wasting disease.

The disease has been especially devastating for the sunflower sea star, a keystone species that plays a crucial role in maintaining the health of kelp forest ecosystems. The study found that the sunflower sea star is now considered "functionally extinct" across much of its former range, with losses exceeding 87% in the few remaining areas where it still persists.

The collapse of the sunflower sea star has had cascading impacts, leading to a "total ecosystem shift" as urchin populations explode without the sea stars to keep them in check. This has transformed diverse kelp forests into barren "urchin barrens," with significant ecological, cultural, and economic consequences.

The researchers spent years trying to unravel the mystery of the disease, which causes sea stars to develop lesions, lose their arms, and "disappear into mush" within a week or two of exposure. After numerous failed attempts, the breakthrough came when the team shifted their focus from examining diseased tissues to analyzing the sea stars' coelomic fluid, which they describe as the "blood" of the sea star.