Sciurus aureogaster F.Cuvier, 1829

Nomenclature

The Mexican gray squirrel, with the scientific name Sciurus aureogaster F. Cuvier, 1829, is also called the red-bellied squirrel; in Mexico, it is known locally as ardilla gris mexicana or ardilla vientre rojo.

Subspecies

This species is split into two subspecies: S. a. aureogaster and S. a. nigrescens. Both subspecies are native to Mexico and southern Guatemala.

Introduced Range

The species was introduced to the Florida Keys in 1938, where it is classified as an invasive species.

Native Range Coloration

Across most of its native Mexican range, the Mexican gray squirrel has a light to dark gray back, while its underside ranges from white to orange to a deep chestnut shade. In northern native populations, individuals commonly have fully black or gray back fur, with faint red coloring on the belly and rump.

Introduced Population Coloration

On Elliott Key, the most common form has entirely black fur.

Native Biomes

This squirrel is native to multiple biomes across Mexico and Guatemala.

Habitat Types

It occupies a wide variety of habitats, including evergreen forests, dry pine-oak woodlands, thorn scrub, secondary forests, plantations, and also regularly occurs in urban areas.

Elevation Range

It has adapted to survive in high-elevation habitats up to 3,800 meters (12,500 ft).

Habitat Preference

It is most often found in dry woodlands or forests, and regardless of location, it prefers habitats with extensive canopy cover or dense forest.

Nest Construction

It builds nests in trees approximately 5–15 meters (16–49 ft) above ground, covering the nests with leaves.

Nest Function

This leaf covering hides the nest from predators and protects the squirrel from harsh weather.

Introduced Habitat Adaptation

After being introduced to Elliott Key, Florida in 1938, the species has adapted to the area's urban and dense subtropical environments.

Introduced Population Nest Similarity

Squirrels in Florida build nests that are very similar to those constructed by their conspecifics in Mexico and Guatemala.

Elliott Key Nest Tree Usage

On Elliott Key, Mexican gray squirrels have been recorded building leaf nests in 12 different tree species, with 60% of all nests located in S. mahagoni.