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Bighorn Sheep:
A symbol of rugged independence, this mountain dweller has captured the imagination of outdoor enthusiasts across the Rocky Mountains. Though historically bighorns were never as populous as other ungulate species found across the West, such as bison and elk, they have long been an important fixture on the western landscape. Due in large part to the unique and inhospitable habitat that they occupy, bighorns inspire a quiet fascination in nature lovers.

As robust in stature as the bighorns may appear, they are highly susceptible to a number of diseases and parasites, which they don’t tend to inflict upon other ungulate species. After hitting a high mark of 487 sheep in 1982, an epidemic of Chlamydia (pink eye) decimated 60 percent of the park’s sheep population. And while currently stable, the population has never fully rebounded. Because bighorns act as an indicator of health for the unique alpine habitats that they occupy--which are hard to reach and even harder to study--close monitoring of their status in Yellowstone will remain an important objective.

There are few experiences in the natural world like observing the thunderous clash of two bighorn rams slamming 40 pounds of horned skull at one another. This raw event occurs each autumn in Yellowstone Country and is a sight every wildland fanatic should witness.

• Both male and female sheep have horns.
• Adult males (rams) can weigh up to 300 pounds, including horns that can weigh upwards of 40 pounds.
• The bottoms of the bighorn’s feet are concave, enabling it to run and walk over the smallest of rocks and other textured surfaces.
• By the time a male is six to seven years old, he will begin to develop the full curl horns that nearly form a circle.
• It is currently estimated that there are approximately 200-275 bighorns in Yellowstone.
• Pneumonia outbreaks during the winter of 2009-2010 killed hundreds of bighorns all across the west.

Rocky Mountain Elk:
The Rocky Mountain Elk (Cervus elaphus) or “wapiti,” as known by the Shawnee, is the most abundant ungulate species in the Yellowstone Ecosystem. Each fall, visitors from all over the globe descend upon this region to view, photograph, hunt, and simply observe one of the great symbols of the Rocky Mountain West. Though they seem to always be surrounded by controversy--with the debate ranging wildly, from too many elk, to too few, especially in Yellowstone’s northern range--they remain a species that carries with them a great reverence and following. The passion of those who pursue elk with a camera, bow, rifle, or pair of field glasses in hand is easily spread to those who witness for the first time the regal display of grace and raw masculinity of a bull elk in the height of the autumn rut.

Working as a ranger naturalist in Yellowstone National Park, I had the unique honor of witnessing firsthand the magnanimity of Yellowstone’s most noble bulls. On countless occasions I was forced to run for my life, eluding the pounding hooves of testosterone-charged males simply looking for confrontation--wherever they might find it. There is always a heightened anticipation in the air each fall in Yellowstone, as the severity of winter is just around the bend; but for those of us who hold great reverence for the 700-pound frame of the bull elk, the clashing of antlers and the romantic vocalizations filling the air stop us in our tracks and give us reason to celebrate the changing of seasons.

•  There are an estimated 20,000 elk in 7 different herds who summer in Yellowstone National Park.
•  The Firehole-Madison herd is the only one of seven herds that stays in the park year round.
•  Average lifespan is 13-18 years of age.
•  The yearly re-growth of a large bull elk’s antlers take approximately four months. Roughly 70% of the growth takes place in the last half of the period and during this time a mature bull elk will grow antlers at the rate of 2/3 inch each day!
•  Bull’s typically become 6-pointers by the time they are four years old.
•  Elk can run up to 35 mph and have been known to jump a 7-foot fence.

Grizzly Bear:
There is perhaps no more authentic representation of wildness in all of North America than Ursus arctos horribilis, the Grizzly Bear. An icon of the Yellowstone ecosystem, the grizzly bear was listed as a threatened species under the Endangered Species Act in 1975. Having been reduced to less than 2% of its historic range in the lower 48 states, the grizzly bear has long thrived in the Yellowstone ecosystem. The history of grizzly bears in Yellowstone dates back to the early years of the park where hand feeding bears—which was prohibited in 1902, but largely ignored until 1970—was the high point of many tourists’ visits to Yellowstone. By the 1930’s, watching bears feed on anthropogenic food sources at garbage dumps such as the Otter Creek bear viewing area, near Canyon Village, hit its peak. Beginning with the Craighead brothers in 1959 (John and Frank Craighead pioneered the study of grizzlies in Yellowstone) and continuing today, the Yellowstone grizzly study is the longest running study of any bear population in the world. Though their numbers dropped significantly, to less than 200 bears by the early 1980’s, the population has rebounded significantly over the course of the last two decades, so much so that the great bear was recently de-listed from the Endangered Species Act. But this does not mean that grizzlies in Yellowstone Country are out of the woods. In fact, quite the opposite is true. Grizzlies are a testament to a critter that will always need a high level of protection and monitoring afforded by acts of legislation such as the ESA, because their habitat continues to grow smaller and more tattered each and every decade. Though the population is on an upward trend, with the loss of key food sources such as the whitebark pine, and the unknown impacts of global climate change, the future of the grizzly in Yellowstone Country is unpredictable. There is no more important piece of grizzly habitat than the human heart, and it will take the hearts of the citizens of Yellowstone Country and beyond to recognize and honor their role as stewards of this incredible animal in order for future generations to have the opportunity to wander through Yellowstone Country with grizzlies on their minds…

All of the following facts and numbers are in relation to the Yellowstone grizzly population only:

•  Adult males weigh between 300-700 pounds with adult females weighing between 200-400 pounds.
•  Adult male home ranges can vary from 800-2,000 square miles.
•  Can run up to 35-40 miles per hour (and can climb any tree you are able to ladder up).
•  Survival rate: Cubs of year 64%, yearlings 85%, ages 2-5 52% and adults 95%.
•  In a meat-driven ecosystem like Yellowstone, the estimated percentage of meat energy in their diet is: 78% males and 45% females (compared to upwards of 90-98% vegetation energy in Glacier National Park grizzlies).

Bison:
Known to most Americans as the buffalo and to biologists as Bison bison, this rugged four-legged beast is a guardian of the plains. Though there are over 300,000 bison being raised in captivity all across the country, including the state of Hawaii, Yellowstone Country is home to the most unique herd of bison in the world. Perhaps the most treasured wildlife population in North America, the Yellowstone bison faces obstacles far greater than Yellowstone’s harsh winters, or its predators. Over the course of the last three winters, over 2,500 of Yellowstone’s wild and free-ranging bison have been shipped to slaughter for following their ancestral instinct to migrate to winter range—all because of Montana’s fear that wild bison will transmit brucellosis to cattle, costing the state its brucellosis-free status. The sacred Yellowstone bison herd will continue to face tremendous obstacles in the future, and it is with great hope that YCG believes progress can be made through collaboration, community based education and outreach, and the creation of a new dialogue throughout the region—a dialogue that replaces the issue-based discussion with a more compassionate and understanding asset-based language.

•  It is estimated that by 1902 there were only approximately 23 wild bison left—which were discovered living in Yellowstone’s remote Pelican Valley.
•  Male (bull) bison can weigh up to 2,000 pounds.
•  The unparalleled rutting season begins in July and ends in late August.
•  Bison can run up to 30 mph.
•  3: the average number of visitors injured by bison in Yellowstone National Park each year.