The Black-tailed Gnatcatcher is a small blue-gray bird of dry scrub in the southwestern United States and Mexico. Breeding males grow a black cap, and both parents take part in raising their young.
It is a small blue-gray bird with a slender bill and tail. Most of the tail is black with a little white at the outer tips, and breeding males have a black cap.
Both sexes build the nest, incubate, and feed the young. Parents often raise a second brood soon after the first.
An extinction-risk assessment has not been added yet.