Coues Deer

Coues deer are a diminutive subspecies of white-tail deer. They are found in Arizona and New Mexico, but their range is more extensive in western and central Mexico.

Coues Deer Facts

• Coues deer are smaller than other white-tail deer, following Bergmann’s Rule that average size is greater for animals farther from the equator.
• The Coues deer was first identified in 1895-1896 by an army physician stationed in Ft. Whipple, Arizona, Dr. Elliott Coues, who pronounced his name “cows.”
• Despite the original pronunciation of the doctor’s name, it is now more commonly pronounced as “cooz.”

Scientific Name

Coues deer are subspecies of the white-tail deer of the Genus Odocoileus, meaning “hollow tooth.” White-tail deer carry the species name Odocoileus virginianus, the Virginia white-tail. Coues deer, named after the doctor who discovered them, are Odocoileus virginianus couesi.

Appearance 

Odocoileus virginianus couesi are smaller than the rest of the white-tail subspecies, measuring about 30 inches tall at the shoulder and seldom reaching 100 pounds. Female adults only average about 65 pounds. Because of their more diminutive stature, their ears and tails seem more prominent than most white-tail deer. Their large ears are crisscrossed with a network of blood vessels that carry blood through the ears to cool before returning to the circular system.

The tail of the Coues deer has the distinctive white underside belonging to all white-tail deer, flashing white as it is raised when alarmed to alert the rest of the herd. A white halo also surrounds each eye. Their coat is lighter in color and duskier than the coat of its Virginian cousin, allowing it to blend in better with its sandy scrub brush habitat. It changes its coat in winter to a darker gray which then becomes more reddish in the spring and summer. Its undercoat in both seasons is lighter in color.

Behavior

Coues are notoriously wary, nicknamed “the grey ghosts.” Although they habitually use the same routes when eating, getting water, or bedding down, they will abandon those paths for a while if disturbed. After a few days, they will return to their habitual trails. Some white-tail will graze with other animals, like cattle or sheep, but the Coues deer will avoid any areas inhabited by livestock.

Habitat

Coues deer inhabit high elevations of the American southwest and Mexico. During the rainy season, they frequent slightly lower elevations seeking out grasslands and scrub oak. They move to higher elevations when the dry season hits, seeking oak groves and pine forests. They are comfortable in vegetation with interspersed clearings. They seem to be most numerous in territories with pine, juniper, and various evergreen plants, but they can also be found in Sonoran Desert regions.

Diet

Coues deer feed on various grass, seeds, acorns, weeds, shrubs, and cacti fruit. They will feed mainly on flowering shrubs and trees, known as “forbs.” Forbs are found in semi-arid areas and grow along the edges of woodlands or patches of juniper, frequently along with long grasses. Though they have their preferences, they will focus on diverse plants rather than staying in an area with only one or two types of vegetation. The shrubs they will eat from include false mesquite, buckwheat, and mountain mahogany.

Predators and Threats

The types of predators Coues deer face are pretty typical. The dry patches of the southwest and Mexico are favorable to mountain lions, coyotes, and bobcats known to prey upon Coues. An occasional bear will also hunt Coues. Small fawns and older deer are particularly vulnerable to all of these predators, as well as dogs and golden eagles.

Reproduction, Babies, and Lifespan

Coues deer “rutting” occurs in the winter, with peak breeding season in December and January. Bucks will mate with many does, which means if bucks are in short supply, the population will still carry on.

About 200 days after conception, does will give birth. Most of these births will occur in August. These births happen after the summer rains, providing deer with the benefits of food and cover resulting from new growth. Does will leave their fawns bedded down while they go to feed. Coues stay with their fawns longer than mule deer will. The first birthing for a doe will be one fawn; afterward, they may birth twins.

Coues deer have a lifespan of 9-11 years in captivity, though in the wild, these numbers are impacted by disease, elements, and predation.

Population

Coues are a subspecies of white-tail deer, and the IUCN lists them as “Least Concern.” Some estimates of Coues in Arizona and New Mexico place the population at about 100,000. In contrast, the population in Mexico is believed to be larger than that, as their range is more extensive.

Coues Deer In the Zoo

If you want to see a Coues deer in person, two parks in Arizona have them in captivity. Bearizona Wildlife Park has a variety of animals, including Coues deer. Grand Canyon Deer Farm also has a collection of deer, including the Coues. Check their sites for costs and hours.