Squirrels of the World

Sciurus anomalus 41

faint buff or yellow, and frosted with white. Melanism has
been reported.

size: Female—HB 220–254 mm; T 217–247 mm; Mass 461 g
(345–510 g).
Male—HB 220–254 mm; T 217–247 mm; Mass 408 g (290–
491 g).

distribution: This species can be found in southeastern
Coahuila through central Nuevo León, and south through
western Tamaulipas to extreme northern San Luis Potosí
(México).

geographic variation: None.

conservation: IUCN status—least concern. Population
trend—decreasing.

habitat: Allen’s squirrel is found primarily in oak (Quercus)
and oak-pine (Quercus, Pinus) forests in montane environ-
ments. However, it does extend into similar habitats in
coastal plains.

natural history: This species is diurnal. Allen’s squirrels
are active on the ground and in the canopy. In mixed for-
ests, S. alleni selects oak (Quercus) and pine (Pinus) forests
during all seasons. Pregnancy and lactation have been re-
ported in all months; litter size varies from one to four
young. Nests are sited in natural cavities in trees or are built
of leaves and sticks placed on tree branches. Primarily her-

bivores, Allen’s squirrels feed upon the seeds and fruits of

nat ive t rees, a s wel l a s on pea nut s, corn (ma ize), oat s, apples,

peaches, mangos, plums, grapes, and tomatoes. They will

also consume insects (adults and larvae) and anurans. S. alleni

occasionally enters cornfi elds and can cause considerable

damage to the ripening crop. Logging, burning, and the con-

version of forests to agriculture are the primary threats to

its conservation.

general references: Best 1995a; Guevara 1998; Jimenez-

Guzman and Guerrero-Vazquez 1992; Leopold 1959; Morales

1985.

Sciurus anomalus (Gmelin, 1778)

Caucasian Squirrel

description: Caucasian squirrels have a dorsum that is

generally grizzled gray to black, often suff used with buff to

Sciurus alleni. Photo courtesy Gabriel Bojórquez.