The sexual behaviour of the fur seals hasn't come as a complete shock to the scientists that recorded it.
In 2006, they saw, for the first time, a fur seal attempting to copulate with a king penguin, on Marion Island, a sub-Antarctic island that is home to both species.
They published details of that incident, and speculated that the sex act at the time may have been the behavior of a frustrated, sexually inexperienced seal. Or an aggressive, predatory act. Or a playful one that turned sexual.
But the new incidents, published in the study "Multiple occurrences of king penguin (Aptenodytes patagonicus) sexual harassment by Antarctic fur seals (Arctocephalus gazella)", still surprised the researchers.
"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," said Nico de Bruyn, of the Mammal Research Institute at the University of Pretoria, South Africa.
All four known sexual incidents followed a common pattern. Each time a seal chased, captured and mounted the penguin. The seal then attempted copulation several times, lasting about five minutes each, with periods of rest in between.
In three of the four recorded incidents the seal let the penguin go. But on one of the more recent occasions, the seal killed and ate the penguin after trying to mate with it.
