Kootenai Critters: Bighorn Sheep, Living Life on the Edge
Here’s what you need to know about northwest Montana’s Rocky Mountain icons
This is the last in our series of blogs that we’ve been publishing monthly throughout the summer to showcase the wonderful wildlife of northwest Montana’s Kootenai National Forest (KNF). If you missed them, take a moment to learn about Grizzly Bears, Bald Eagles, and Westslope Cutthroat Trout.
The KNF houses wild places like the Cabinet Mountains Wilderness, Scotchman Peaks, and Yaak Valley. This summer, we’re making it easy to show off your Kootenai pride, even if you don’t live in northwest Montana. This is the last week to take the quiz to discover your secret Kootenai critter identity, enter the giveaway to win great outdoor gear (this month’s prizes are a Kelty sleeping bag and Klymit sleeping pad), and sign the pledge to care for the future of the Kootenai National Forest.
We’ll send everyone who completes the quiz a free limited-edition hand-drawn sticker of their Kootenai critter identity! Monthly giveaway winners will also receive an enamel pin.
The arrival of the bighorn
About 750,000 years ago, the ancestors of the Rocky Mountain bighorn sheep crossed the Bering Land Bridge from Siberia into Alaska. From there, they spread throughout the West, finding homes in rocky terrain from Canada down to northern Mexico. Bighorn sheep populations peaked in the millions, and they were an important resource for Indigenous peoples all along the mountainous spine of the Rockies. The sheep provided meat, clothing, and tools, and held different mythologic and symbolic meanings for various tribes. Petroglyphs featuring bighorns are among the most common historic images across the western U.S.
A worthy name
A bighorn ram’s horns are massive and curled, up to 45 inches long. A pair might weigh up to 30 pounds, and the sheep that carries the set would tip the scales at 300 pounds. Think of this: those 30-pound horns weigh more than all the bones in his body combined. Ewes also have horns, but they’re thinner and more gently curved, rather than curled. Ewes seldom weigh more than 150 pounds.
Headbutts you can hear
Each fall, rams fight for dominance and mating rights. Facing each other, the two competitors rear up on their hind legs before hurling themselves at each other in short charges that can reach 20 miles an hour. The crash from this mighty headbutt can be heard echoing through the mountains from a mile away as the confrontation is repeated – sometimes for hours – until one ram submits and walks away. The animal's thick, bony skull usually prevents serious injury, but rams' horns frequently show damage from repeated clashes.
Look for the ledges
Bighorn sheep can be found in several areas of the Kootenai National Forest. If you’re interested in spotting them, look for land with nearby access to cliffs and rocky ledges. They can be found in valleys, foothills, and high on mountains, but having a safe rocky retreat close at hand gives them an advantage over predators (open areas also make it easier to spot predators, so you won’t often see bighorns in thick forest.) Bighorns can’t move well through deep snow and prefer drier slopes, often with a southerly aspect. This also means they’re generally found at lower elevations in the winter and higher elevations in the summer.
Although not quite as nimble as their distant mountain goat cousins, bighorn sheep have become well-adapted to their vertical habitat. Their wide-set eyes are large and positioned forward on the head to provide a wide arc of keen vision. They have split hooves with an outer rim of tough, specialized toenail that conceals a softer inner pad that conforms to the rock and helps the sheep grip small ledges. Thanks to their amazing balance, bighorn sheep can stand on ledges that are only 2 inches wide. They can also jump 20 feet, climb up a mountain at a brisk 15 mph, and run up to 30 mph on flatter ground.
Good eats and vertical retreats
During the summer months, bighorns eat grasses, sedges and clover. In the winter, they will eat willow and sage to survive. These don’t sound delicious or nutritious to humans, but bighorn sheep are ruminants, which means they have a complex four-part stomach that enables them to eat large portions rapidly before retreating to cliffs or ledges where they can thoroughly rechew and digest their food, safe from predators. Specialized bacteria in the bighorn’s gut then takes over, breaking down plant fibers for digestion. The sheep also absorb moisture during this digestive process, enabling them to go for long periods without water.
Each spring, lambs are born on high, secluded ledges protected from bighorn predators such as wolves, coyotes, and mountain lions. However, this survival strategy doesn’t work against the golden eagles who target the newly born lambs. The young sheep can walk soon after birth, and at one week old each lamb and its mother join others in a herd, where the group works together to protect themselves from predators by facing different directions, keeping watch against all threats.
Threats to the bighorn sheep
Two hundred years ago more than 200,000 bighorn sheep lived throughout the western United States, Canada, and northern Mexico. A dramatic drop in population occurred from 1870 to 1950, crashing bighorn numbers to just a few thousand. Unregulated hunting, habitat destruction, overgrazing of rangelands, and diseases contracted from domestic livestock all contributed to the decline.
There are now about 70,000 bighorn sheep living in North America. Much of their historical range no longer supports bighorn populations and Interstate Highways have cut off once-connected mountain ranges. Modern threats include habitat loss (primarily from housing development and OHV use), water loss caused by human diversion or livestock use; mining, vehicle collisions, herbicide/insecticides/fatal plants on golf courses, and climate change. Together, these factors continue to seriously threaten bighorn populations.
Bighorns are very sensitive to changes in the environment. They are often referred to as an “indicator species,” meaning that a healthy, thriving herd of bighorns is indicative of a healthy, thriving ecosystem. About 5,000 bighorn sheep currently live in Montana, in a population classified as stable.
Bighorn sheep are part of our western culture, loved by locals, prized by hunters, and oooh’d over by tourists. They’re a species so closely tied to some of our most treasured and threatened landscapes that to protect one is to preserve the other.
Learn what you can do today to help protect bighorn sheep habitat, and other key wild places, in our action center. “Ewe” know your actions can have mighty “ram”ifications!
Help us protect animal habitat in the Kootenai and throughout Montana
MWA works to protect Montana’s wildest places, including bighorn sheep habitat in the Kootenai National Forest.
Join us in protecting bighorn habitat, and Montana’s countless other wild public lands. By joining our monthly donor program, the Wild Bunch, you’ll cement your place as a wilderness superstar and help protect the wild places and wildlife that we love and depend on.
Northwest Montana Field Director
Allie finds common ground with communities and individuals in northwest Montana to protect this wild and wet corner of our state. In her free time, she bakes pies, carves spoons, and plans her dream garden. She also likes to ski and hike.