Bridled Titmouse, Baeolophus wollweberi

Bridled Titmouse, Baeolophus wollweberi phillipsi. Photograph taken within a residential community in Hereford, Arizona, February 2007. Photograph and identification courtesy of Bob Behrstock, Sierra Vista, Arizona (naturewideimages.com).

Background and Identification

The Bridled Titmouse, Baeolophus wollweberi phillipsi, is one of four subspecies of Bridled Titmouse, three of which are found in Mexico. They are a member of the Paridae Family of Tits, Chickadees, and Titmice, which has sixty-three members placed in thirteen genera and is one of five global species of the Baeolophus Genus. They are named for their striking facial pattern. Their diets include insects, both adults and larvae and acorns during the winter. They have life spans of less than four years but have been poorly studied. Very little about their biology and behaviors has been documented. They are also known in Mexico as Herrerillo Embridado.

The Bridled Titmouse is small in stature with a head crest. Average length is 10 cm (3.9 inches) with an average mass of 10 g (0.35 oz). The sexes are visually identical, known as sexual monomorphism. The back of their head is black, and the sides are white with black bridled markings. Their back and tail are gray, and the underparts are light gray to white. Their bill is black, the gape is pink, their iris is dark brown, and their legs are bluish gray.

Habitat and Geographical Range

The Bridled Titmouse favors oak and oak-pine woodlands. This species is smaller and more acrobatic than other titmice and acts more like a chickadee than a titmouse. During the non-breeding season, the Bridle Titmouse is found in large flocks of other insectivores, including chickadees, creeps, kinglets, nuthatches, tanagers, vireos, warblers, and vireos. They are believed to be a nuclear species, which means they control the assemblage and moves of the mixed flock.

The Bridled Titmouse is a year-round resident of Mexico with many fragmented populations. They are found throughout the Sierra Madre Occidental mountains from northeast Sonora and northwest Chihuahua south through eastern Sinaloa, western Durango, and eastern Nayarit to northern Michoacán above 2,000 m (6,560 feet). In the Sierra Madre Oriental, they are found from central Nuevo León and western Tamaulipas south through northern Puebla to west-central Veracruz above 2,000 m (6,560 feet). In the Sierra Volcánica Transversal of central Mexico, they are found from northern Michoacán east through Morelos and Puebla to west-central Veracruz, usually above 2,000 m (6,560 feet). In Sierra Madre del Sur they are found from western Guerrero to central Oaxaca, west of the Isthmus of Tehuantepec, at elevations above 1,900 m (6,230 feet). The phillipsi subspecies is found in southeastern Arizona, south of the Gila River, south to western Chihuahua, and southern Sonora. In northern Mexico, some birds move to lower elevations and riparian areas during the winter. This is called altitudinal migration.

Common Misidentifications

The Bridled Titmouse can be confused with other small songbirds, particularly those in the same family, Paridae. One common look-alike is the Black-crested Titmouse, Baeolophus atricristatus, which shares a similar size and shape but has a black crest and lacks the distinctive black-and-white facial markings of the Bridled Titmouse.

Conservation Status

From a conservation perspective the Bridled Titmouse is currently considered to be of Least Concern with stable, widely distributed populations. However, southern populations are being depleted by the transformation of oak woodlands into croplands, and populations in central Mexico have been adversely affected by the removal of oak woodlands.