Bird nests are safe and warm places for babies to be protected and loved.The tufted titmouse (Baeolophus Bicolor) and its close relatives use this material, which is often the fur mammalian carnivores. Scientists thought that the fur was either snatched from the shed animals or pillaged.However, new observations have shown that this is not true: The feathered filchers often purloin fur from living predators.Jeffrey Brawn, an ecologist at the University of Illinois at UrbanaChampaign, stated that "the titmouse" he saw was plucking hairs from a live animal.This was a live raccoon, with teeth and claws. The raccoon seemed to not mind, as it didn't even get up."Brawn noticed the behavior while doing a bird count in Illinois. He was so fascinated that he set out to find an explanation.He was joined by Henry Pollock and Mark Hauber from the University of Illinois Urbana-Champaign. They discovered that fur theft is only mentioned sparsely in scientific literature. However, YouTube videos uploaded to the site by bird enthusiasts proved to be an extremely rich resource.These videos show tufted titmice plucking fur from domestic cats and dogs, as well as a porcupine. Other videos also showed fur theft by other bird species, which was not scientifically documented.Although the literature is lacking in records, it seems that the fact that birds steal fur from living mammals from living animals is well-known to the public. In Australia, the yellow-faced honeyeaters and the Cornell Lab webpage for the species are both described as fur thieves occasionally.Researchers have given the behavior kleptotrichy (from Greek for "theft" or "hair") as their name.It was interesting to note that YouTube searches yielded many examples of birds removing shed animal fur from their environment. This suggests that they are not stealing the material.This raises the question: Why take the chance of stealing your hair?Although fur from animals can help to insulate nests and keep them warm, researchers think that fur from predators could have other benefits.Brawn explained that there is a local species of great crested flycatcher. It, like the titmouse and a cavity nester, actually places shed snakeskins in its nest to deter predators. African finches exhibit similar behaviors, using predator feces to deter predators (and wouldn’t it?).The fur may even repel parasites that can quickly kill small hatchlings. It is possible for birds to line their nests with plant materials, which can repel parasites. However, it is not clear if mammal fur might have similar properties.While further research is needed to determine the benefits birds get from their misdeeds and the extent of the harm they cause, preliminary geographical analysis by the team has shown that kleptotrichy occurs more frequently in higher latitudes. This suggests that fur is collected to keep nests warm.It is important to have actual scientific documentation about kleptotrichy in order to figure it out. This provides important information that other researchers can build on.Pollock stated, "Unexpected interactions like these remind us of animals' many interesting and often overlooked behavior and highlight the importance to carefully observe natural history in order to shed light on the intricate nature of ecological communities."Ecology published the research.