Bacterium Identified in Massive Pacific Sea Star Die-Off

Scientists have identified Vibrio pectenicida, a bacterium related to those causing cholera in humans and shellfish, as the cause of the sea star wasting disease that has killed more than five billion sea stars and affected over 20 species along the Pacific coast of North America since 2013. The discovery followed a decade of investigation that initially focused incorrectly on a viral cause and was ultimately resolved through analysis of coelomic fluid from infected sea stars. The disease has wiped out about 90% of the sunflower sea star population, leading to unchecked sea urchin numbers and devastation of kelp forests, which are critical carbon sinks and marine habitats. Scientists hope this breakthrough will inform restoration and management efforts, including research into treatments and the influence of warmer ocean temperatures on the outbreak. The findings offer new hope for reversing the impacts of one of the ocean’s most severe recent epidemics. Outbreaks continue to occur seasonally, particularly during periods of elevated temperatures.