These are small bird sucking insects that usually thrive in the nests of birds and other wildlife. When these birds are nesting in some cavity of our homes, these blood sucking pests can enter inside our homes and start to bite us.
Bird mites can trace their way to a suitable host as they have very sensitive receptors that can direct them to moisture, heat and CO2. It is because of this uncanny ability that these insects are noticed by people when they crawl near their mouth, nose, eyes, ears, armpits and groin area. These parasites would be able to better target a human as it sleeps or rests. The heat sensing ability of bird mites is sensitive enough to differentiate a difference in temperature by as little as one Fahrenheit.
These parasites are present in wildlife spaces. Sometimes these get hitched to our pets and our persons and become our direct parasite pests.