Please visit For more information about PLOS Subject Areas, click Then, in the summer of that year, scientists and others watched with horror as one of the largest marine die-offs in modern history played out before them. scientific or professional broadscale monitoring data, citizen science data, species-targeted collection data for varied purposes) to determine population level impacts. (e) Wasting lesion on central disk. (Photo by Ben Miner) Beginning in 2013, a mysterious disease crippled sea star populations up and down the U.S. west coast. Photo by Sue Daly/Minden Pictures
A general return to the pre-2013 sea star abundance seems unlikely, Harvell says.Despite the massive die-offs and the continued, though significantly reduced, presence of SSWD, some scientists such as Cornell University marine microbiologist Ian Hewson remain hopeful that sea stars may eventually recover by adapting to the new environmental conditions.Hewson, who was not affiliated with Harvell’s team, says that animals such as sea stars that reproduce quickly and in large numbers tend to adapt pretty rapidly to environmental change.Chris Iovenko is a writer and filmmaker in Los Angeles, California with many documentary and narrative film credits. “The sea stars don’t have a chance when it’s warm.”Although warming ocean temperatures appear to play a role in exacerbating the disease, as more research and data continues to come in, any tidy, unified answer as to what single factor or combination of factors caused SSWD has proved elusive.“When you look across some of these big outbreaks we’ve had in the past it takes a very long time to get to the end answer,” says Harvell.
Already there are a few hopeful glimmers. Sea star wasting disease (SSWD) describes a suite of disease signs believed to have led to catastrophic die-offs in many asteroid species, beginning in 2013.
In both field and laboratory settings, morphological signs associated with SSWD appeared similar to those observed in larger asteroids, including white lesions on the rays, twisting arms, and loss of rays [We encountered several challenges when observing physical signs of SSWD in We report a pattern of local absence in timed count surveys, in at least 5 populations of Laboratory experiments and observations conducted on Due to sea stars’ important predatory role in rocky intertidal ecosystems, it is critical to determine how populations may recover from mortality events, and we must explore treatment options when possible.
Although the virus appears to have spelled doom for sunflower stars, other sea star species are not affected by it.
Drastic changes in abundance in echinoderms have been associated with direct and indirect anthropogenic effects [Comparing disease-affected organisms with different life histories remains a crucial goal of ecological surveillance. Classically, higher host population density is thought to increase disease transmission (e.g., [Given that SSWD has been reported in up to twenty species of asteroids [Local abiotic effects may also affect disease impact. The use of shared datasets and data repositories, such as This study used data collected by the Multi-Agency Rocky Intertidal Network (MARINe), a long-term ecological consortium funded and supported by many groups.
Photographs were taken beginning at the time initial signs of wasting were observed and ending either at sea star death or the end of the treatment period. Share this: Share on Flipboard From Mexico to Alaska, sea stars withered and died, their bodies dissolving into mush, leaving nothing but goo and spines behind.Over the next two years, as geographically diverse populations continued to crash, scientists coined the term sea star wasting disease (SSWD) to refer to the unexplained forces that were causing the devastation.