Mexican Spotted Owl Strix occidentalis lucida
The Mexican spotted owl is one of three subspecies of S. occidentalis. The owl is about nineteen inches long, with a wingspan averaging 3.3 feet.1 It has brown upper-parts spotted with patches of white.1 The owl has large dark eyes, and lacks ear tufts. The legs and feet are fully feathered.2
The Mexican spotted owl occurs in a variety of habitats, consisting of mature montane forests, shady canyons, and steep canyons. The key components in montane forests appear to be characteristics common in old-growth forests: uneven-age stands with high canopy closure and tree density, fallen logs and snags.2
The Mexican spotted owl has the largest geographic distribution of any of the S. occidentalis subspecies.3 Historically, the owl ranged from the southern Rocky Mountains in Colorado; the Colorado Plateau in southern Utah; southward through Arizona, New Mexico, and far western Texas; in Mexico through the Sierra Madre Occidental and Oriental mountains and the southern end of the Mexican Plateau. Presently, the owl's range reflects the historic range, but owl numbers are much reduced and habitat is patchy.
The owl's diet consists of rodents, birds, lizards, insects, and occasionally bats.1 The spotted owl hunts by 'perching and diving.'2 The owl will spend minutes, even hours, perched on a branch waiting for prey to venture near. When prey is spotted, the owl swoops down and grabs the prey with its talons.2
Mating begins mid-February to March and egg-laying follows in April to May. The owls usually use nests built by other animals. The female lays one to three eggs which are incubated for twenty-eight to thirty-two days.1 The young owlets fledge in June, thirty-four to thirty-six days after hatching. By October, the young are fully independent.2
The Mexican spotted owl was listed threatened April 14, 1993. A recovery plan was approved for the owl in December 1995.
Mexican Spotted Owl in Pima County:
Pima County is included in the Basin and Range-West area of the Mexican spotted owl recovery plan.4 This area ranks third highest in the U.S. for known Mexican spotted owl populations. The owl has been found in the Santa Catalina, Rincon, Whetstone, and Santa Rita Mountains.2 The threats to the owl in this region include catastrophic wildfire, recreation, and grazing.4 Due to the suppression of fire and the build up of fuel loads, wildfire is viewed as the primary threat to the owl in Pima County. Vast numbers of people enjoy recreational activities which has led to the continuing creation of facilities used for recreational purposes. This construction can potentially alter owl habitat. Cattle grazing may impact the owl by destroying riparian habitats that the owl may use as dispersal corridors. This may inhibit gene flow among populations. New approaches to forest service management need to be implemented to ensure the long-term survival of the Mexican spotted owl.4
1. Arizona Game and Fish Department. 1998. Strix occidentalis lucida. Heritage Data Management System.
2. BISON-M Taxonomy. October 16, 1997. Mexican Spotted Owl (Strix occidentalis lucida).
3. Heck, Jennifer. June 30, 1993. Mexican Spotted Owls: Federal Protection. Congressional Research Service. Washington D.C.
4. U.S. Fish and Wildlife Service. 1995. Recovery plan for the Mexican spotted owl: Vol. I. Albuquerque, New Mexico. 172 pp.