Mountain Pygmy Owl

The Mountain Pygmy Owl, Glaucidium gnoma, is a diminutive raptor from the Strigidae family. This species is a resident of southern Arizona, New Mexico, and extends into Mexico. It is a subject of taxonomic debate, with some considering it a separate species, while others view it as a subspecies of the Northern Pygmy Owl, Glaucidium californicum.

Identification Tips

Adult Mountain Pygmy Owls measure a mere 15–17 cm in length, with males weighing between 48 to 54 grams and females slightly larger at 60 to 73 grams. They exhibit reverse sexual dimorphism, with females being the larger sex. Their plumage is typical of pygmy owls, with a white chest and throat, a rufous facial disk, and a pale rufous base color with cream spots on the head, neck, wings, and tail. The tail features 5 to 6 alternating bands of white and rufous, and the underside displays white with vertical, broken streaks of red-brown. Their eyes, feet, and bill are a striking yellow.

Habitat

Mountain Pygmy Owls favor pine-forested mountains, particularly those with Ponderosa pines, as the open understory aids in their hunting. They inhabit elevations ranging from 1,500 to 3,500 meters in tropical and subtropical forests of oak, pine, and evergreens.

Distribution

This species is found from southern Arizona and New Mexico down to Oaxaca in southern Mexico.

Behaviour

Known for their aggressive and solitary nature, Mountain Pygmy Owls prefer to live alone except during the breeding season. They are diurnal hunters, actively pursuing prey during the day, and are known to be mobbed by songbirds, which forces them to seek new hunting grounds.

Song & Calls

The vocal repertoire of the Mountain Pygmy Owl includes territorial "hooting" or "tooting" calls, often heard around sunrise and sunset. Males and females engage in duetting, with the male initiating and the female responding in a lower tone. Their calls vary geographically, with different patterns of single and double hoots noted across their range.

Breeding

Breeding pairs are monogamous for the season and may return to the same nesting site for several years. Nests are typically in tree cavities or woodpecker holes. The female lays 2 to 4 white eggs, with incubation lasting around 28 days. Chicks hatch close together and fledge 23–30 days later, with parental care continuing for several weeks thereafter.

Similar Species

The Mountain Pygmy Owl can be distinguished from other members of the Northern Pygmy Owl complex by its size, tail length, and wing-tip shape. The Guatemalan Pygmy Owl, for instance, has more vibrant red-brown plumage and distinct tail bars.

Diet and Feeding

Their diet includes insects, small mammals, and a significant portion of songbirds. They have a high metabolism and require a constant food supply, consuming prey head first and regurgitating indigestible parts as pellets.

Conservation status

The IUCN lists the Mountain Pygmy Owl as a species of Least Concern. However, there is concern that deforestation could impact future populations, suggesting a potential decline in numbers.