Scientists say that some bird species routinely take hair from unsuspecting animals to make nest linings. They recently published a study that details hair theft and cite numerous YouTube videos showing birds doing it. Although it is not clear why hair is so appealing to birds, it could be used to repel predators or act as an insulator.AdvertisementMany birds have been known to use hair and fur from mammal mammals in their nests, especially species belonging to the Paridae family, which includes chickadees and tits. It is generally believed that these birds steal hair from dead animals or carcasses. Jeffery Brown, a University of Illinois Urbana-Champaign professor of natural resources and environmental sciences, noticed that a titmouse was stealing hair from a sleeping raccoon. The raccoon did not seem to notice.Brown and his colleagues were intrigued by the robbery, so they began to investigate the phenomenon. They now call it kleptotrichy, which roughly translates to Greek as hair-stealing. Last month, Ecology published a paper on the common but often overlooked behavior of birds stealing mammal hair. They describe the initial incident, which is believed to have been the first known raccoon hair-theft in published bird science, as well as other incidents they discovered in their subsequent research.They found 11 instances of kleptotrichy in academic literature. Most of these were from the Paridae family. They discovered a wealth of videos online from birding enthusiasts and were able to search for them in academic literature. They found 99 instances of kleptotrichy by birds against humans, dogs and cats, raccoons, and even a porcupine. The majority of these sightings, which included the original raccoon theft incident, were of the tufted titmouse, Baeolophus bicolor. However, two other Paridae species could also be seen in the videos.Researchers wrote that the sheer number of sightings on tape suggests that kleptotrichy might be far more common than what is indicated in the scientific literature.It is still unknown why these birds would risk their lives to get hair. The insulation power of mammal hairs is well-known, so it's possible that the birds are taking advantage of this. It is possible that the smell from the hairs could be enough to repel predators or parasites. Some birds even add mammal poop as a deterrent to their nests.In a university statement, Henry Pollock, co-author and postdoctoral researcher at University of Illinois Urbana-Champaign said that unexpected interactions like these are a reminder of the diversity of animal behavior and the importance of natural history observations to illuminate the intricate details of ecological communities.AdvertisementWhatever the reason, they are likely to steal hair from living targets. This is yet another example of how little we know about the lives and habits of animals around us.
