Picture of monk seal with eel up its nose shared by Noaa was only latest episode to occur in the past two years, baffling researchers

The Hawaiian monk seal has become endangered due to a range of threats, from fishing net entanglements to disease. Now the beleaguered species is facing an unexpected new challenge – eels getting stuck up their noses.

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A picture of a monk seal with an eel up its nose was shared this week by a Hawaii-based division of the National Ocean and Atmospheric Administration (Noaa). The episode was just the latest eel-in-snout incident to occur in the past two years, baffling researchers.

“We’ve been intensively monitoring monk seals for four decades and in all of that time nothing like this has happened,” said Charles Littnan, the lead scientist at Noaa’s Hawaiian monk seal research program. “Now it’s happened three or four times and we have no idea why.”

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Researchers first spotted a seal with an eel nasal appendage in the summer of 2016, emailing colleagues who initially thought it was a joke. It has since happened enough times for the monk seal program to develop guidelines on how to remove the eels.

“They get stuck in there really snug, so you have to restrain the seal and give the eel a firm tug to get it out,” said Littnan. “One of them was really far in so it was like a magician’s handkerchief trick, we just had to keep pulling and pulling.”

The phenomena could cause potential problems for the seals in terms of infections or even by affecting their ability to dive and feed on marine creatures. Seals typically seal their nostrils shut when diving into the water, a process hampered by the presence of a nose-dwelling eel. “Having a rotten fish inside your nose is bound to cause some problems,” Littnan lamented.

Researchers have managed to successfully remove all of the protruding eels, all from juvenile seals, but are still trying to ascertain why this is happening.

One theory is that seals, which often regurgitate their meals, are simply throwing up eels through their noses. Another is that startled eels get stuck there while attempting to flee the seals as the predators forage for food beneath rocks. Either way, scientists are unsure why this nasal entrapment is only now being witnessed by humans.

“If I had to guess, I would say that it’s one of those strange oddities,” Littnan said. “If you observe nature long enough, you’ll see strange things.”

Monk seals are endemic to Hawaii and are listed in the US as an endangered species, with around 1,400 individuals remaining. Threats including fishing and disease, with climate change another looming challenge.