If there’s one thing that keeps the internet a-buzzing, it’s a good, old-fashioned scientific mystery. And lately, Starfish Wasting Syndrome (SWS), a troubling illness that has been devastating populations of starfish (also known as sea stars), is taking centre stage.

Scientists are working hard to uncover the mechanism driving SWS, but of course, the web waits for no one. And as with most bizarre and baffling mysteries-gone-viral, this one has generated a flurry of misinformation. And so the Earth Touch myth-busting crusade continues. Let’s put a few sea star speculations to rest.

Myth #1: The 'zombie arms' of sick starfish crawl on to claim new victims

Starfish Wasting Syndrome causes a slew of gruesome symptoms, including white lesions and decaying tissue, and loss of body pressure. But nothing has grabbed media attention more than the autotomised arms, which contort into unnatural shapes before tearing from the body. The severed arms do spend some time tube-feet tiptoeing about, but this is not the starfish zombocalypse it seems to be. 

Though some starfish, especially in the genus Linckia, reproduce by autotomy, not one of the species that have been affected by SWS do so.

"I’ve been around the temperate Pisaster species for decades now,” said Dr. Allison Gong, who recently watched in horror as the stars in her seawater table fell victim to SWS. "I’ve never seen the cast-off arm do anything other than slowly die over a period of days. Nor have I seen any reports of autotomized Pisaster arms going on to regenerate entire stars," she said.

The most likely fate of the eerie arms, she goes on to explain, is to be gobbled up by scavengers. While scientists have not yet determined if eating infected tissue has an effect on healthy animals, there is no evidence to support the claim that the arms generate new infected stars.

SWS can cause the arms of the starfish to fall off, sometimes within just hours. Image: Ed Bierman, Flickr

Myth #2 This is a new, never-before-seen phenomenon

Though wasting syndrome resurfaced last year, this is not the first report of a decaying starfish epidemic.

"One of the earliest accounts of starfish wasting disease was recorded from southern California (Channel Islands) in 1997," Smithsonian National Museum of Natural History researcher and author of the Echinoblog Christopher Mah said. 'The starfish guy' himself noted similar arm contortions in the species Pycnopodia helianthoides in 2011. 

“[It’s] hard to know if it was the same thing or something 'important', or even relevant," he told Earth Touch. "The development of the disease may vary by location and/or environment. Type of species, location, water quality, temperature or some other environmental variable may be at play,” he said. 

And, speaking of location, let's move on to Myth #3.

Myth #3: This ain’t nothin’ but a West Coast thang

Contrary to some media reports, SWS is not confined to America’s Pacific coast. Similar echinoderm dieoffs have been recorded on the east coast.

University of Rhode Island researcher Caitlin DelSesto reported watching the sea stars of her research 'melt and die'.

"If you pick up a healthy sea star, they're pretty firm,” she said. "But [the] sick ones are slimy and mushy. You might see white lesions on them that are eating away the tissue. Sometimes they'll release all [of] their arms as a reaction to the stress they are under."

Sounds familiar, eh?

Myth #4: Other organisms at risk

This myth is half-busted.

It’s important to note that in nearly all videos highlighting wasting syndrome outbreaks, including this recent video from PBS, the surrounding flora and fauna seem healthy and vibrant.

"One cannot help but notice that other than the starfish, EVERYTHING else remains alive,” Mah said. “Fish. Seaweed, encrusting animals, etcetera.”

If these organisms appear immune to infection, why is this myth only half-busted? The answer: ecology.

Starfish are voracious carnivores and many hold important predatory roles in the ocean’s ecosystem. Like with any keystone species, a massive dieoff could have a cascading impact on organisms in other trophic levels (that is, on other steps in the marine food web).

Which brings us to the mother of the starfish myths.

Myth #5: Starfish wasting syndrome has something to do with Fukushima radiation

Radiation from the Fukushima nuclear power plant is not a likely cause of starfish wasting syndrome. Not today. Not tomorrow. Just. No.

Our friends at Deep Sea News have compiled some excellent resources on radiation, its physical properties, and its effect on marine life – but this myth can be busted just by thinking critically about what Mah has explained. 

  • Wasting syndrome has been observed on the east coast of the United States – where no evidence of Fukushima radiation exists.
  • Organisms living closely with sick starfish are not showing symptoms or behaviours of concern.
  • Starfish wasting syndrome pre-dates the Fukushima disaster – by at least 14 years! 

Have you witnessed SWS in your area? Join the conversation and help researchers track its progression by tweeting using the hashtag #sickstarfish. 

Top header image: Daniel Arndt, Flickr