Growing Number of Seals Raping, Eating King Penguins in Antarctica

South African seals are capturing, raping and eating their fellow penguin inhabitants on Marion Island.

Scientists made the disturbing discovery after examining video footage of wildlife on the sub-Antarctic Indian Ocean Island.

Researchers from the University of Pretoria have documented the bizarre cross-species sexual harassment in a new study titled "Multiple occurrences of king penguin (Aptenodytes patagonicus) sexual harassment by Antarctic fur seals (Arctocephalus gazella)."

In the study, scientists described four separate cases of fur seals brutally attacking and mounting adult king penguins, according to the Daily Mail.

All the sexual assaults followed a specific pattern in which the giant seals chased, captured and penetrated penguins, International Business Times reported.

In one particularly horrific incident, a seal killed and ate its victim after mating with the resisting bird. However, the seals let the penguins go in the other three sexual assault incidents.

Scientists first discovered the bizarre behavior in 2006 when a fur seal was seen attempting to mate with a king penguin on Marion Island. However, the latest study reveals that these seal-on-penguin attacks are becoming more common.

'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 the BBC.

Bruyn and his team said that all the documented cases involved male seals. However, they were unable to determine the gender of the penguins. The penetration time ranged from two-and-half minutes to six minutes with resting periods in between.

Scientists are still trying to figure out the reason behind this increasingly widespread behavior. Bruyn and his team speculate the unusual phenomenon might be the result of learned behavior as it was seen in four different seals.

"Determining the drivers of the unusual behavior is nearly impossible," said de Bruyn, according to The Metro. "However, we speculate as to what may have ultimately led to the sexual coercion of individuals from these very different species."

"We really can't think of what the reward may be for these young males, other than perhaps learning that these birds are an easier target to practice their copulatory skills," he said, according to International Business Times. "Perhaps it is a release of sexual frustration, given the hormonal surges during seal breeding season. It is very unlikely to be failed mate recognition."

The findings are published in the journal Polar Biology.