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America's Greatest Animals Facts

Kali, a young adult female mountain lion, checks out her environment with her keen, predatorial vision.

America's Greatest Animals (View larger version)

Photograph by Grizzly Creek Films/Avela Grenier



  • Bull elk are famous for bugling – a loud call that rises from low to high and then descends back down the scale.

  • The oldest cow leads elk herds. The cows determine the herd's actions, except during the rut (or mating period), when dominant bulls take control.

  • Wolves

  • A lone wolf will send up a shrill howl to attract the attention of his pack, and a pack of wolves may howl to convey messages about territory to another pack.

  • The gray wolf (Canis lupus) used to inhabit all of North America as far south as central Mexico. It has been exterminated in most US regions and is now rare throughout the country except in Alaska, with small populations persisting in Minnesota and the northern Rockies.

  • Gray wolves hunt prey within a large range of size, from as small as a mouse to as large as a moose.

  • Bison

  • Bison are the largest terrestrial mammals in North America. They stand 5-6.5 feet tall with horns up to 2 feet long and can weigh over a ton, yet they can run up to 40 miles per hour.

  • Bull bison establish dominance by "butting heads and pushing each other," with the champions winning the right to "tend" a small group of cows.

  • Moose

  • Moose can sprint up to 35 miles per hour and maintain 20 miles per hour at a trot.

  • Moose are the largest and heaviest of all the deer species - their antlers can spread over six feet from end to end and weigh over 30 kg (approximately 66 lbs).

  • Sheep

  • Male Rocky Mountain bighorn sheep drive towards each other at up to 20 miles per hour, clashing with their signature curled horns repeatedly and loudly, fighting for mating rights.

  • Before they mate, big horn sheep ewes are chased at high speeds on the faces of steep precipices, occasionally setting of small rockslides down the sheer slopes.

  • The big horn sheep horns are made of keratin (around a bony core), a material similar to that of animal hooves, bear claws, and your fingernails.

  • Mountain Lion

  • Mountain lions are responsible, on average, for one human fatality every other year over the last two decades in all of the United States and Canada.

  • Cougars

  • Cougars are ambush predators. They prefer to take down deer and elk but will eat anything from grasshopper to moose.

  • Bears

  • Contrary to their name, black bears can be a range of different colors, from blue-gray or blue-black, brown or cinnamon, to even white.

  • During the dormant period in winter, black bears do not eat, drink, urinate or defecate. They do, however, wake up if disturbed – making them not true hibernators.

  • Approximately 70% of human fatalities from grizzly bears are due to mother bears defending their cubs.

  • Although typically brown, a grizzly bear's fur can appear to be white-tipped, or "grizzled".

  • Unlike black bears, grizzly bears generally do not climb trees.

  • Polar bears weigh up to 600kg (1,323 lbs.) and measure nearly 2.6m (8.5 ft.) from the tip of the nose to the end of the tail.

  • Female polar bears give birth to two cubs, who stay with her until they are 2 years old, when they can then hunt and survive on their own.

  • Eagle

  • When bald eagles attack their prey, they drop down at up to 100 miles per hour (161 kilometers).

  • Even though the white head of a bald eagle may make them appear "bald," the name actually comes from its Greek name Haliaeetus leucocephalus which means 'white-headed sea bird.'

  • Because of its ability to tolerate cold climates, the caribou is not endangered.

  • Caribou

  • Caribou have one of the world's longest migrations of over 3,000 miles.

  • Caribou are the only deer in which the females have antlers, as well – although not all females have them.

  • Pronghorns

  • Pronghorns are the fastest land animal in North America, running at speeds close to 60 miles per hour.

  • Pronghorns rarely drink water, receiving most of their water from the plants they eat.