A mysterious health condition is actually causing starfish to tear themselves to pieces, literally.
Scientists with the United States Geological Survey's National Wildlife Health Center say the arms of infected starfish begin to twist and then crawl, pulling away from and eventually off of the bodies entirely.
To make things worse, the resulting holes, from which the starfish's innards are then spilling out, are not able to heal, due to the disease.
The afflicted stars die within a day, say USGS officials
Scientists say they first detected the mass deaths among one star species, the sunflower starfish, last June.Divers and scientists first reported the macabre illness along the Washington state coast, although infected starfish have since been sighted in the waters of Alaska, as well as Southern California.
Now the condition, dubbed "sea star wasting syndrome," has spread to 12 species, affecting stars in the wild and also in captivity, according to Jonathan Sleeman, director of the wildlife health center.
'The two species apparently most affected by the phenomenon are Pycnopodia helianthoides, also known as the sunflower sea star, and Pisaster ochraceus, otherwise known as the purple sea star or ochre starfish, Sleeman said in a statement issued late last year.
The sunflower star is considered among the largest of all starfish species and can measure more than three feet in diameter.
The most notable symptoms of the wasting syndrome are white lesions on a star's arms which spread rapidly, soon leading to aberrant behavior and loss after that.
Data from the USGS indicates entire star populations have already been wiped out along the California coast, in the Puget Sound and north of there, in an intricate network of waterways around northwestern Washington state and the Canadian Province of British Columbia.
Scientists put the mortality rate of the disease at a staggering 95 percent.
One diver was quoted in the media saying the underwater scene near the coastline of Seattle looked like a horror film, with "bodies everywhere."
Scientists say they still don't know what's causing the wasting syndrome, identify the cause, though ' Pete Raimondi, chair of the department of ecology and evolutionary biology at the University of California in the Bay Area told reporters the stars are likely being ravaged by some sort of pathogen, like a parasite, virus or bacteria, that is compromising starfish immune systems.
A a smaller outbreak killed East Coast sea stars last year, leading some scientists to speculate ocean acidification or even climate change could be at least partially responsible, though most researchers think a pathogen is, indeed, the main culprit.
An epidemic nearly wiped out the Pisaster ochraceus from tidal pools along the southern coast of California in 1983, while a smaller die-off in 199 was believed caused by warmer waters caused by El Nino-year currents, scientists said.
A decline in the starfish population would have a serious impact of the ocean ecosystems, as the multi-armed creature eat mussels, barnacles, snails, molluscs and other smaller sea life, keeping the populations of those other creatures under control. Then, they likewise are consumed by other starfish, shorebirds, gulls and even sea otters.
Citizen scientists are being asked help track the spread of the wasting syndrome by reporting via social media (and using the Twitter address #SickStarfish) the locations of any dead starfish they may see.