Abert’s squirrels are found sporadically throughout the Rocky Mountains, from Arizona to Mexico. They are named in honor of Col. John James Abert, an American soldier, and naturalist.
|Also known as
|Size: They reach a total length of around 17.8-22.8 in (45-58 cm), the tail adds another 7.5-9.8 in (19-25 m)
Weight: Their average weight is usually 21.9 oz (620 g)
Color: Varies between subspecies; usually a grey fur with a white ventral side and a conspicuous rust colored stripe on their back; some subspecies are entirely black
|Distribution & Subspecies
|Sciurus aberti aberti: Northern Arizona
S. a. chuscensis: Arizona-New Mexico border
S. a. kaibabensis: Kaibab Platue in Arizona
S. a. mimus: New Mexico-Colorado border
S. a. ferreus: The Rocky Mountains in Central Colorado
S. a. navajo: Southeastern Utah
S. a. barberi: Northwestern Chihuahua
S. a. durangi: Durango
S. a. phaeurus: Southern Chihuahua and Durango
|Most abundant in ponderosa pine forests, but may also be seen in mixed forests, especially in New Mexico and Mexico
|Sounds & Communication
|They use a variety of sounds like squeals, screeches, clucks, barks; also communicate through visual means and touch
|Data regarding life-expectancy in the wild is deficient; a captive individual lived for seven years
|Feeds on ponderosa pine tree parts like seeds, cones, buds, fungi, and the inner bark; in areas where this tree is not available, they exhibit similar feeding habits but from different trees
|Since they spend most of their time on trees, they have a light and agile frame that helps them climb and leap from one branch to another; they shed their thick coat and tasseled ears during summer to keep up with the changing climate
|Coyotes, mountain lions, bobcats, and northern goshawks prey on these rodents
|IUCN Conservation Status
These squirrels are diurnal, becoming active a little before sunrise, and returning to their nest before sunset, foraging at intervals throughout the day. They build these shelters or nests on dwarf-mistletoe infected twigs in ponderosa pine trees. They are not territorial but remain solitary from late spring to autumn.
Mating & Reproduction
During mating season, which occurs between February and June, male Abert’s squirrels led by a dominant individual ‘chase’ after a female through the forest for hours. Females are promiscuous and copulate with multiple partners. The gestation period is around 43 days, ending with a litter of one to five newborns.
The babies are about 0.43 oz (12 g) at birth. They are weaned after around 70-76 days and weigh 12.5 oz (355 g) by this time. They reach sexual maturity when they are around 327 days old.
- The mule deer takes advantage of the Abert’s squirrel’s arboreal feeding habits; as soon as the latter drops something from high up in the tree, the mule deer waiting at the bottom eats it up.
- Ponderosa pines produce a pungent chemical called terpene to dissuade these rodents from feeding on its parts.