[Photo] A colony of Adélie penguins on the West Antarctic Peninsula. CREDIT: Sue & Wayne Trivelpiece

Hidden for nearly 100 years for being too "graphic," a report of "hooligan" behaviors, including sexual coercion, by Adelie penguins observed during Captain Scott's 1910 polar expedition have been uncovered and interpreted.

The naughty notes were rediscovered recently at the Natural History Museum in Tring, in England, and published in the recent issue of the journal Polar Record.

George Levick, a surgeon and the medical officer on Scott's famous 1910-1913 expedition to the South Pole, called the Terra Nova expedition, detailed his account of the penguins' seemingly odd behaviors in a four-page pamphlet "Sexual Habits of Adélie Penguins" in 1915. (The expedition, led by Navy Captain Robert Falcon Scott, would arrive at the South Pole to discover that Amundsen had beaten them there.)

During their journey, Levick observed and recorded details on the lives of the Adélie penguin (Pygoscelis adeliae) colony on Cape Adare. He even recorded the very first penguin to the colony — the world's largest of this species — on Oct. 13, 1911.

"Some of the things he noticed profoundly shocked him," said the museum's bird curator Douglas Russell, who discovered the pamphlet. For instance, Levick noted the penguins' autoerotic tendencies, and the seemingly aberrant behavior of young unpaired males and females, including necrophilia, sexual coercion, sexual and physical abuse of chicks, non-procreative sex and homosexual behaviors.

Considered too explicit for society at the time, the pamphlet wasn't published with the other Terra Nova expedition reports. As such, it remained hidden in the bird collections at the museum to be uncovered recently by Russell.

"Levick's notes were decades ahead of their time and possibly the first ever attempt to reveal the more challenging aspects of bird behavioral strategies to the academic world," Russell said in a statement.

At the time, Levick was so shocked by what he saw he recorded the events in Greek to disguise the information, at one point writing, "There seems to be no crime too low for these penguins.

Levick described penguins that waddled about the colony's outskirts terrorizing any straying chicks as "little knots of hooligans" in his pamphlet. "The crimes which they commit are such as to find no place in this book, but it is interesting indeed to note that, when nature intends them to find employment, these birds, like men, degenerate in idleness."

Homosexual behaviors in animals are no longer cause for hiding data, or even a blush. (Case in point: Dutch biologist Kees Moeliker won an Ig Nobel prize in 2010 for the first report of dead gay duck sex.)

Plenty of animals are out of the closet, so to speak, from dolphins and killer whales to bonobos and greylag geese. Some estimates put the number of animal species that practice same-sex coupling at 1,500.

And while Levick may have viewed the interactions between penguins through an anthropomorphic lens, today that's not the case, the researchers note.

Necrophilia, for instance, is not the same in penguins and humans; Rather than being sexually aroused by a hot gal, male penguins are chemically wired to respond in certain ways to a seemingly compliant female of breeding age.

"I'm very pleased that, 97 years after Levick submitted it for publication, the study has finally been published," Russell said. In fact, no other studies on this colony have been published, the researchers note.

Some 100 copies of Levick's pamphlet were originally printed, though only two are known to exist today.