From "mutant" eels to fish "tumours", viral stories linking the Fukushima nuclear disaster to seemingly strange marine events are probably crowding your news feed. And each time one pops up, radiation-related panic spirals ensue.

The latest addition revolves around a group of fin whales that stranded in Alaska recently. The post has been shared thousands of times across social media platforms, but like many before it, it's rife with inaccuracies.

Fukushima-fin whale-2016-2-28
Image: MV Kennicott crew, NOAA

You don't need to go much beyond the headline – "Whales Continue to Die Off in Pacific Ocean: Scientists Suspect Fukushima Radiation at Fault" – to know what you're in for. But here's the catch: the scientist quoted in the article, marine mammal specialist Kate Wynne, never linked these events to Fukushima at all.

We subsequently checked in with Wynne, who explains that while the whales' deaths were not linked to toxic algal blooms (or "red tide"), this does not mean that scientists suspect a sinister cause of death.

"Samples from marine mammals found dead in Alaska since the Fukushima disaster – including one whale I sampled last summer – have been tested for radiation (Cesium-137 and other) exposure," she says. "Levels of radionuclides in their tissues did not exceed background levels found in ocean waters, indicating Fukushima radiation exposure was not the cause of their death. We are testing for Fukushima radiation exposure whenever we can – and have not found it."

It's always distressing to read about animals washing up dead, deformed or injured, and our need for a satisfactory explanation is completely understandable. But it's also critical that we take a moment to sort fact from fiction before hitting that oh-so-tempting "share" button.

On that note, you've probably come across some of these "Fukushima-related" images before – and the facts behind these stories might surprise you.

The UK sperm whale stranding

Vandals in the UK wasted no time pinning the deaths of five sperm whales on Fukushima radiation (protip: spray-painting whale carcasses is illegal in many countries and carries hefty fines! Don't do it.)

Here's the problem. Physical oceanographer Dr Kim Martini explains that radiation potent enough to kill a whale would need to be so concentrated that it would certainly kill everything else around the giant animal first. Radiation poisoning this strong would come from eating affected fish, who were eating affected plankton – and so on. Just as with toxins, radioactive isotopes are concentrated as they move through the food web. But in the UK stranding case, no other species washed up. "There is no way these whales died this way," says Martini.

Dr Paul Jepson of the UK Cetacean Strandings Investigation Programmewho has done extensive work on contamination in the area, agrees. The most likely culprit, in fact, is the topology of the North Sea itself, which is notorious for causing strandings.

"We definitely don't think that radiation killed the sperm whales," says Jepson. "More likely is that they got into the relatively shallow North Sea which is shaped like a whale trap – and just could not find their way back to the Atlantic. Once they strand alive they get crushed under their own body weight."

He adds that the sperm whales that stranded in the UK may be part of a larger group that faced the same fate in the Netherlands (six whales) and Germany (six whales), none of which tested positive for high levels of radiation.

Shark tumours and fish 'cancer'

Images: Andrew Fox, Robbins et al. (left), Wikimedia Commons (right)

First things first: yes, fish (including sharks) can get cancer. But neither of these viral images are quite what they seem.

The salmon image – featured in articles like "We're Eating Fukushima Radiation: Bloody Cancerous Tumors in Fish & Seafood" – actually shows the effects of a well-known parasite, Henneguya salminicola. The spots you see in the photo (which was taken in 2009, two years before the Fukushima disaster!) are cysts, not cancerous tumours. The milky liquid in the cysts houses the parasites within the fish's muscle tissue.

The shark image, on the other hand, does show a tumour, but the scientific paper it was taken from had nothing to do with radiation. The aim of the study was to use observations of sharks near Australia's Neptune Island to dispel the myth that sharks cannot get cancer a fallacy that was thought to contribute to the demand for shark cartilage. After decades of work, scientists have documented tumours in at least 21 species of sharks, none of which have been linked to Fukushima.

That pesky Facebook collage

fukushima-facebook collage-2016-2-25

In addition to the examples above, this viral collage, which has been shared extensively over the past month, is filled with cherry-picked images that have been stolen from various websites. Most of them, including the riverfish in the upper right corner, pre-date Fukushima. And the entire lot is being used out of context. Perhaps the most disturbing misrepresentation is the inclusion of the lesion-covered shrimp.

The shrimp photo was lifted from an Al Jazeera article, which reported on the suspected link between contamination from the Deepwater Horizon oil spill and the spread of disease in local marine life. In this case, blaming Fukushima diverts attention away from a very real concern and the work of dedicated scientists.

The supersized sea monster

Image: Hiroshi Hirasaka/Twitter

As we've reported before, this is no mutant. It is a very old and very healthy wolffish caught by fisherman Hiroshi Hirasaka off the Japanese coast. And even though that puts the animal "at the scene" of the disaster, there is still no scientific evidence to support claims that Fukushima fallout has, or will, result in mutant fish. Even right after the catastrophe, a swim in nearby waters would have dosed you with just 0.03% of the daily radiation an average Japanese resident receives. And much of that fallout has disappeared because of natural decomposition and decay.

Besides, even in the extremely unlikely event that radiation was the culprit here, we would actually expect to see smaller, not larger, fish. "Very, very few mutations lead to extra-large size," explains University of South Carolina radiation specialist Dr Timothy Mousseau. "[Instead], they grow less efficiently, they're less capable of catching food and they tend to not live as long." 

The starfish with 'too many' arms 

Image: Jerry Kirkhart/Flickr

If you're not an expert, it's easy to misidentify this strange-looking sea star as a freak of nature, but in reality it's perfectly normal. This is a sunflower star (Pycnopodia helianthoides), a species known for its radial array of 20 (or more) arms. For more amazing examples of sunflower stars, check out this post from the EchinoBlog's Dr Christopher Mah. 

And while we're on the subject, Starfish Wasting Syndrome also pre-dates the Fukushima disaster – by at least 14 years!

The jumbo squid stranding

Last month, Chile's Isla de Santa Maria was suddenly littered with the crimson carcasses of over 10,000 dead Humboldt squid. But contrary to media reports, and a slew of scaremongering YouTube videos, this is a known phenomenon.

The large cephalopods (Dosidicus gigas), sometimes called “jumbo squid” or “red devils”, have been documented stranding like this since 2002, nearly a decade before the Fukushima disaster occurred.

The likely explanation is that the squid encountered an offshore warm-water blob that commonly forms in the area during the Southern Hemisphere’s summer months – and recent El Niño weather patterns mean it will be sticking around longer than usual.

the amazing technicolour lobster

Image: Chad Graham

To end on a colourful note, this lobster's stunning hues are – wait for it –  also not a radiation mutation. The condition is known as "crystal lobster", and the chances of spotting it are about one in 100 million

Like this all-white great white sharkthis spotted right whale and this all-black frogfish, the technicolour lobster's strange appearance is the result of a pigment irregularity. It can be caused by a genetic mutation similar to leucism, which results in partial loss of pigment, but interestingly, a shift in diet throughout a lobster's life can also result in the morph.

Lobsters feed on a wide variety of small organisms, but two of their favourite foods – shrimp and algae – contain a great deal of astaxanthin (the pigment that makes carrots orange and flamingos pink). In fact, it's because of all that astaxanthin that lobsters turn bright red when exposed to heat during cooking. But a diet devoid of the pigment can cause warped colouration.


That concludes our tour of Fukushima fables, folks. And this list isn't just about knowing the facts. The planet's oceans face plenty of very real and well documented threats, from plastic pollution to warming waters – so debunking fabricated stories that detract from legitimate problems is important if we want to protect marine life.

If you've spotted a Fukushima rumour that we didn't tackle here, chances are it's one of the 28 fallacies explained in this great article from Southern Fried Science or this "True Facts" article from Deep Sea News.


Top header image: George, Flickr