[2] The American bushtit's distinguishing characteristics are its petite size, its plump and large head, and its long tail.

[citation needed] Their food source is small insects, primarily, spiders in mixed-species feeding flocks.

[4] Bushtits live in flocks of 10 to 40 birds and family members sleep together in their large, hanging nest during breeding season.

Bushtits display a unique behavior as adult males are typically the helpers that assists and raises the nestlings; hence it has intrigued many naturalists for its interesting breeding and mating patterns.

[5] The scientific name Parus minimus was given to the bushtit after it was originally described in 1837 by American naturalist and ornithologist John Kirk Townsend, where he reported that the species inhabited the forests of the Columbia River.

[10] With a length of 4.3 inches and a weight of 0.18-0.21 ounces, the American bushtit is one of the smallest passerines in North America.

It is mostly gray-brown in color, with a large head, short neck, long tail, and small, stubby beak.

Nest locations are typically found on tree trunks or branches, ranging in height from three to one hundred feet.

[12] Female bushtits lay plain white oval eggs in batches of 4-10, but both parents share the responsibility of incubation for 11–13 days.

[12][13] During the breeding season, male and female bushtits form pairs, actively participate in nest-building, and both engage in rearing the young.