Over 90 species of mammals call Grand Canyon National Park home, giving this park higher mammalian species diversity than Yellowstone. From the largest land animal in North America to some of the highest bat species diversity in the United States, Grand Canyon is home to a far larger mammalian population than many people think. Most visitors to the park see mule deer, elk, and squirrels, but many of Grand Canyon's mammals are secretive or nocturnal and move around unnoticed.
Grand Canyon National Park is home to one of the highest bat diversities anywhere in the United States, providing habitat to 22 species of bats. Many bats in the park eat insects, with the Little Brown Bat (Myotis lucifugus) capable of eating 1,200 mosquito-sized insects an hour. Others feed on fish and yet others eat the nectar of fruit producing plants-helping to pollinate the plants. Although it’s unlikely you’ll encounter all of Grand Canyon’s bat species during your visit, look into the evening and night skies to view the only mammals capable of true flight.
One of the largest and most charismatic of Grand Canyon National Park's wildlife is the desert bighorn sheep. This species is the largest native animal in the park with males weighing up to 300 lbs (135 kg), though two nonnative species living in the park, bison and elk are larger. Though bighorn are generally associated with mountainous terrain, the unique landscape found in the Grand Canyon provide excellent habitat unlike any other on earth. The canyons have provided remote refuges for these animals and this is the only non-reintroduced population of desert bighorn.
The Grand Canyon is home to one of the world’s largest species of skunk, the American hog-nosed skunk (Conepatus leuconotus). The park is north of the species’ known range, but two skunks were reported by river trips on the Colorado River in 2014. It is unknown whether the species has been overlooked in the Grand Canyon in the past, or if it has expanded its range northwest. These sightings suggest a breeding population on both sides of the river. Park biologists are beginning a study of the distribution and presence of hog-nosed skunks in the canyon.