Some may find this story disturbing. Things are getting very strange very fast on a small island in the sub-Antarctic. That's because a number of fur seals are chasing down and forcing themselves onto king penguins for no discernible reason. Some of the assaulted penguins have even been eaten afterwards.

This was first noticed in 2006, when a team of researchers witnessed a male fur seal (Arctocephalus gazella) attempt to have sex with a king penguin (Aptenodytes patagonicus) it had captured on the small Marion Island.

The study, which detailed this unusual encounter, was published in the Journal of Ethology two years later. Authors of the study had speculated that this was a rare and isolated occurrence, in which a sexually frustrated and confused male was acting out.

This was either an uncharacteristically aggressive predatory act tainted with sexual drives, or a playful act with a penguin that turned sexual, they speculated.

However, three new occurrences of seal-on-penguin sexual coercion have been observed by researchers on the same island in recent years, suggesting that this is more than just a freak occurrence. It may even be the start of a new and disturbing behavioral trend among male fur seals.

That's at least according to a separate study recently published in the journal Polar Biology.

"Honestly I did not expect that follow up sightings of a similar nature to that 2006 one would ever be made again, and certainly not on multiple occasions," Nico de Bruyn, of the Mammal Research Institute at the University of Pretoria, South Africa, told BBC.

The researcher was involved in both published studies concerning these strange coercions, and still remains completely baffled by them. In one of the more recent occasions, an attacking fur seal even ate its captured penguin after trying to have sex with it.

"This really made us sit up and take notice," said de Bruyn. "It is very unlikely to be failed mate recognition - i.e. the misidentification of the penguin as a female seal."

He and his colleagues speculate that while the cause of this bizarre behavior remains unclear, it may be becoming more popular as fur seals have been known to learn new behaviors from one another.

That's disturbing news, especially if you're a sub-Arctic penguin.


[Credit: Original content from W.A. Haddad/Polar Biology]