A purple squirrel - yes purple - is turning out to be an animal mystery after a couple in Pennsylvania found the unusual critter in their backyard.

Percy and Connie Emert of Jersey Shore, Pa. found the never-before-seen purple squirrel in their backyard during a hunt for rodents that infested their garden and ate food set out for birds, according to news reports from AccuWeather.com.

Instead, the couple came upon a squirrel that is colored entirely of purple, fur, lips and even teeth sharing the royal hue.

The couple released pictures on Facebook and even set up a Twitter account (@PurplSqurl) for the unusual squirrel.

Squirrels normally are colored gray, black, brown, red and in rare cases white. But there are no known cases of purple squirrels other than in corporate recruiting where the expression means the ideal candidate and a mixed drink.

The couple released the squirrel back into the wild, so unless someone else catches the unnamed purple squirrel, no one will really know why the animal has that color.

The idea that the purple squirrel fell into a vat of dye or paint has been discounted since the creature likely would not have survived the toxic paint job.

Krish Pillai, professor at Lock Haven University of Pennsylvania, speculated that the color could come from bromide, a substance found in molluscs, which would give the squirrel a Tyrian purple hue.

The purple squirrel joins a list of creatures that have puzzled onlookers and scientists alike.

The Montuak Monster washed ashore in Montauk, N.Y. in the summer of 2008. The monster had no hair, pink and purple skin and a head with what looks like a stunted beak with canine teeth.

Many concluded that the creature was a raccoon, but forensic analysis was never done and the creature was thrown back into the ocean.

Since then, Nicky Papers, the Suffolk County, N.Y. resident who originally found the decomposed creature of established Montauk-Monster.com as a news source of other found creatures that resemble the original monster.

Little did I know that what I saw that day would be on the news, be the topic of dinner conversations, and become an internet sensation. Since I saw it up close and personal, I will try my best to uncover the truth about the Montauk-Monster. Please check back frequently as the discovery continues, he writes.

The most recent sighting of a Montauk-like monster came in November from Milford, Conn. People have reported other beasts on beaches in Long Island, Montreal and Galveston, Texas.