The Blue-gray Gnatcatcher, scientifically known as Polioptila caerulea, is a diminutive songbird with a notable presence despite its size. Adult males boast a blue-gray hue on their upperparts, contrasting with their white underparts. They possess a slender, dark bill and a long, black tail with white edges. Females exhibit a more subdued blue coloration, while the juveniles are tinged with greenish-gray. Both sexes are characterized by a distinctive white eye ring.
When attempting to identify this species, look for the combination of its blue-gray upperparts, white underparts, and long black tail with white edging. The white eye ring is a key feature to distinguish it from similar species. The male's vibrant blue-gray coloring is more pronounced than the female's, which can aid in sex identification.
The Blue-gray Gnatcatcher is found in open deciduous woods and shrublands. It has a preference for humid areas with large leaves and woodlands, but can also be seen in more open, sandy areas with sparse trees.
This bird breeds in southern Ontario, the eastern and southwestern United States, and Mexico. It is the sole gnatcatcher species to breed in Eastern North America. During the non-breeding season, it migrates to the southern United States, Mexico, northern Central America, Cuba, the Bahamas, the Turks and Caicos Islands, and the Cayman Islands.
The Blue-gray Gnatcatcher is an active bird, often seen hovering over foliage to glean prey or flying out to catch insects in mid-flight, a behavior known as hawking. The tail is frequently held upright while the bird is defending its territory or foraging for food. Males are known to participate actively in nest building, incubation, and feeding of the young.
The vocalizations of the Blue-gray Gnatcatcher are more commonly heard on breeding grounds, away from the nest. Calls consist of a sharp "zkreee, zkreee, zkreee," while songs are a more complex "szpree zpree spreeeeey spree spre sprzrreeeee."
Both parents collaborate in constructing a cone-like nest on a horizontal tree branch, using spider silk and lichen to hold it together. They share the responsibility of feeding the young. The incubation period ranges from 10 to 15 days, and it is possible for them to raise two broods within a single season.
The diet of the Blue-gray Gnatcatcher primarily consists of insects, insect eggs, and spiders. They exhibit foraging behaviors such as gleaning and hawking to capture their prey.
The Blue-gray Gnatcatcher is currently listed as Least Concern on the IUCN Red List, indicating that it is not at immediate risk of population decline or habitat loss.