The western coast of the US and Canada has turned into a graveyard for thousands of starfish, and now we know why.
A disease that leads to the sea creatures literally wasting away, before melting into mounds of goo, has finally been discovered. A densovirus is suspected to be behind the mass cull, with up to 20 species suffering the grim fate once infected.
“The disease leads to behavioural changes, lesions, loss of turgor, limb autonomy, and death characterised by rapid degradation,” reads the research, with ‘limb autonomy’ clearly a terrifying detail.
Lesions appear on the starfish about eight to 17 days after viral infection, with extreme lethargy setting in. “Sometimes the animal’s arms rip themselves off and walk away,” explains National Geographic. “Eventually, the sea star deflates into a pile of white slime.”
Starfish are integral to their habitat, keeping populations of mussels and barnacles at manageable levels and ensuring other algae and snails add variety to the environment.
Mass multi-species death very concerning
Their mass death has been reported for many months, with the cross species element of the now-discovered virus concerning many.
The sea-star associated densovirus (SSaDV) in question has even been found in museum specimens from the 1940s, with its spread explained by its detection in plankton, sediments and in nonasteroid echinoderms.
There’s very little anyone can do to halt the spread of this deadly virus.
“We can’t quarantine, we can’t effectively cull, and we can’t vaccinate,” said Drew Harvell, a marine ecologist at Cornell University in Ithaca, New York, in an interview earlier this year.
The best they can hope for, according to National Geographic, “is that populations can recover once the epidemic winds down”.
“Urchins and cucumbers seemed to have escaped the ill effects of the virus until now. But in recent weeks, reports have started to come in that they, too, are dying along beaches in the Pacific Northwest.”
Starfish image via Shutterstock