Animal Vanity? Vultures Mysteriously Slather Their Faces With Mud as 'Makeup'

Who knew animals liked makeup too? One species of vultures certainly do, smearing red soil on their faces in mysterious behavior that leaves scientists baffled.

According to a report from New Scientist, the rare phenomenon is called cosmetic coloration. New footage shows Egyptian vultures on Fuerteventura island in the Canaries off the coast of Africa sticking their heads in a puddle of red soil, swiping side to side to make sure their head, neck and chest are thoroughly painted red.

Before they put on their "makeup", Egyptian vultures have bright yellow faces and white feathers on their head and neck. This particular population in Fuerteventura is well-documented by scientists with nearly all of the vultures marked with plastic rings. It's the first time researchers have ever documented this unique behavior in individually marked wild birds.

To observe the process, the team set up two bowls in the island's feeding station: one with just water and another with red soil dissolved in water. A total of 90 vultures stopped at the station in a single day and 18 took mud baths and dyed themselves red.

The birds didn't follow a specific pattern to the mud painting nor did were the baths limited to a particular age or sex.

"The most interesting part of our observation is that there is great variation among individuals in the extent to which they paint feathers, ranging from almost completely white to almost completely red," Thijs Van Overveld of Doñana Biological Station in Spain explained.

Scientists are now trying to determine the reason behind the Egyptian vultures painting themselves red. While bearded vulture used it to signal dominance, researchers doubt this is the case here since bearded vultures perform their mud baths in secret and their solitary nature make displays of dominance more important.

It could also be a way to combat bacteria and viruses, although if so, more vultures would be putting on their makeup.

Instead, scientists believe the mud baths are more for visual purposes, similar to the way flamingos gloss their feathers. Further studies may be needed to conclude the function of the Egyptian vultures' strange behavior.

The study is published in the journal Ecology.