Tag Archives: pronghorn

Octo-Ungulates

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Ungulates. The most boring animals on earth. All they do is stand around and chew their cud.

~Hal Brindley

It seems there are not a lot of quotes out there about ungulates (hoofed mammals) but I found this one in a clever blog post by someone that I know through social media. I agree with him, that ungulates often get overlooked by a lot of people when there are charismatic mega-fauna like wolves and bears around, but they shouldn’t be, as they are fascinating and beautiful in their own right. Yellowstone has eight species of ungulates (hence the title), seven native to the region (Elk, Bison, Mule Deer, White-tailed Deer, Rocky Mountain Bighorn Sheep, Pronghorn, Moose) and one introduced to the area (Rocky Mountain Goats). On this trip, we managed to see the seven native species. It isn’t easy to spot a white goat high on a mountain slope in winter! Not many years ago, the toughest two of the ungulates to find in the park were Moose and White-tailed Deer (Mule Deer are the dominant of what are usually considered deer in the park). But, the past few years we have been seeing more of our familiar white-tails, and this year, was a relative banner year for Moose (more on them in a future post).

Here are some tales (and tails) of some ungulates we observed…

Many of these grazers move to lower elevations in winter due to the usual heavy snow in much of the park.They tend to congregate in the Northern Range due its lower snow pack and in areas near or beyond the North entrance at the town of Gardiner, MT. Indeed, one of the hazards of staying where we did, several miles north of Gardiner, was that we had to run the gauntlet of roadside Elk every morning and evening in darkness (definitely not a critter you want to encounter with your vehicle). These large members of the deer family undoubtedly gain another advantage by relocating to these areas in winter as there are probably fewer wolves due to the human presence (although that means they do encounter hunters).

We saw huge herds of Elk near Gardiner and out in Paradise Valley, north of the park (click photos to enlarge)
A magnificent bull Elk along the Old Yellowstone Trail Road

The town of Gardiner lies in a rain shadow area and is below 6000 ft in elevation, so it tends to have milder winters than most of the park. It is amazing to me how the wildlife adapts to the town (and vice versa). One example is the use of the school’s athletic field as a hangout and grazing spot for Elk, Bison, Pronghorn, and a variety of other critters. I like to think that one unique form of detention at this school involves going out to the field and removing the scat piles before a game.

Attracting wildlife to your school yard is probably not a teacher workshop they need in Gardiner

One ungulate, in particular, tends to leave all but the lowest elevations of the park (near the North entrance) every winter – the Pronghorn. Though they are common in Lamar Valley in summer, they all migrate over 25 miles to spend the winter near Gardiner or even farther north. Deep snow makes it difficult for them to browse and greatly diminishes their primary defense against predators – their speed. They are the fastest land mammal in North America, reaching burst speeds of a little over 60 mph and capable of sustained speeds of 45-50 mph. This makes them the second fastest mammal on Earth, second only to the Cheetah (but Pronghorns can keep up a fast speed longer than a Cheetah). Their large eyes are located on the sides of their head to allow for all-around viewing. And they have a large (for their size) heart, windpipe, and lungs, allowing them to get plenty of oxygen and blood supply for their high-octane movements.

There were large herds of Pronghorn on the Old Yellowstone Trail Road out of Gardiner
Male (top) and female (head down) Pronghorns. Males have prongs on their horns and a black patch along the jawline and neck area. Females can have horns (most do) but they are shorter and lack the prongs..

Since vision is such an important trait for Pronghorns, and since they live in herds in open habitats, they have another communication signal used to alert other herd members of danger. If a Pronghorn sees a predator, it raises the white hairs on its rump, making a large white patch visible for considerable distances. They also release an alarm odor from glands on the rump (it supposedly smells like buttered popcorn – probably why you never see Pronghorns at the movies…they would be freaked out all the time).

A buck Pronghorn watching a photographer who has left his car and is walking toward the animals

Below is a Pronghorn rump in action…

A calm rump patch
A “hey dude, why are you getting out of your car for a photo” rump patch
The aforementioned photographer crept closer to the Pronghorn, eliciting this displeased response (see how raised the white rump hairs are)

I stayed in my car and spent about 45 minutes watching the Pronghorn feed. This is what I really like to do – watch wildlife going about their daily lives. Staying in your vehicle or sitting quietly helps wildlife feel more at ease and allows them to continue feeding, or doing whatever, undisturbed.

Along the same road, there was a large group of Rocky Mountain Bighorn Sheep grazing at the foot of the ridge-line. Many photographers stopped to get photos and one grpup, unfortunately, hiked over to the base of the ridge and obviously disturbed the herd as they moved up the slope. I saw this behavior way too often in the park this time.

On another drive down this road, I had to stop to let a small band of ewes and young cross the road in front of me. I managed one portrait as they sauntered across.

A bighorn ewe in the golden light of late afternoon

Among the most photographed animals I saw on this trip were a group of bighorn rams hanging out at the usual small cliff near the confluence of Soda Butte Creek and the Lamar River. This is consistently a good spot for sheep in the winter as I guess the small steep rock face provide just enough protection as an escape from potential predators like wolves. The cliff is a short walk from a pullout and you can get decent images from the roadside, which doesn’t seem to bother the rams at all. Here are a couple of examples…

The first ram I saw was lounging on a snow bank chewing its cud
This ram had everyone’s attention because of its perch on the top of the cliff. I walked down away from the small cluster of roadside photographers and found a spot where the ram was silhouetted against a patch of blue sky through the tree limbs
From another angle, the ram’s horn curl was on full display

More on the magnificent horns of these rams in a future post.

Finally, a few images of the iconic Bison, America’s National Mammal (designated as such with the passage of the Bison Legacy Act in 2016). It joins the Bald Eagle as a national symbol and represents an amazing comeback from the brink of extinction. Bison numbers went from an estimated 30-40 million roaming North America in the early 1800’s, to fewer than 1000 individuals less than 100 years ago. The causes of this precipitous decline included uncontrolled market hunting (Bison hides were highly valued) and a concerted effort by the U.S. military to remove Native American tribes from the land by taking away their main food source: Bison. Some Bison found protection on private ranches, In Yellowstone, the numbers dwindled to about 24 Bison that survived deep in the park’s interior. In one of the first efforts to try to restore a wild species, park officials in Yellowstone began to manage the remaining herd and enhanced it with wild Bison purchased from private owners. The herd was ranched in Mammoth and then in Lamar Valley at the Lamar Buffalo Ranch. Today, the park’s herd numbers about 5000. More information on Bison and the history of management in the park can be found here.

I have always had an affinity for Yellowstone Bison (I blame the movie Dances with Wolves), so I try to spend some time alone on each trip with these iconic creatures. I managed to spend over an hour one day with two large bulls, watching them feed in a picturesque valley below the towering Baronette Peak. Snow was falling, and then patches of blue sky would appear, and then more snow. None of it fazed the Bison as they plowed through the snow with their massive heads.

Two bull Bison in the lower Baronette area
This old bull was plowing snow with his head to reach grasses underneath
Here is the Bison carcass that had been picked clean by wolves and scavengers. You can see the thoracic vertebrae are long, giving the Bison the humped appearance. This provides attachment points for the massive neck and shoulder muscles Bison use to snow plow through deep snow to access dried grasses.
I watched this bull for about 15 minutes before it raised its head out of the snow for this pic
The other bull was covered in snow as it fed (these photos are cropped images from photos taken with a long lens from the roadside)

I’ll end with one of my favorite teacher quotes from my museum workshop days, penned by Donna, after spending time observing a herd in Lamar Valley…

What must it be like to be a Bison, to own nothing yet have everything?

Sagebrush Speedsters

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Pronghorn bucks on ridge

Pronghorn bucks on ridge

One of the changes I’ve noticed in the 25+ years I’ve been going to Yellowstone is an increasing number of Pronghorn in recent years. It used to be that you saw them mainly around the Gardiner area, but now they have greatly increased in numbers across the northern range, especially in Lamar Valley and Little America. Although the genus name, Antilocapra, means antelope and goat, Pronghorns are neither. They’re the only surviving member of a North American ungulate (hoofed mammal) family.

Pronghorn buck

Pronghorn buck

These graceful animals get their name from their unusual horns. Both male and female Pronghorns have horns, but only the males have the distinctive prong the juts forward halfway up from the base. Males can also be distinguished by their black cheek patches, absent in females. The horns consist of a bony interior attached to the skull covered by a black keratinous sheath.  The sheath is shed annually like antlers. Male Pronghorns use their horns in competitions during the rut and may deliver serious piercing stabs to their opponents.

Pronghorn buck 5

Pronghorn running

Pronghorns are well-known as the fastest mammal in North America, able to reach speeds of over 60 mph and sustained speeds of up to 40 mph.  They are also one of the fastest mammals on Earth – one reference said a Cheetah could outrun a Pronghorn in a short sprint but a Pronghorn would quickly pull ahead as the Cheetah tired. Pronghorns may have evolved this running ability to escape the now extinct American Cheetah, and adults can easily outrun any of the modern-day predators they encounter. They can run across a football field with as few as 10-12 bounds in as little as 3 seconds. Pronghorns have several adaptations that allow them this speed. Their heart, lungs and trachea  are several times larger than similar sized ungulates; their blood is rich in hemoglobin; and their long legs have light-weight, yet strong, leg bones.

Pronghorn rump with hairs raised

Pronghorn with rump hairs raised

They have several other adaptations that enhance their survival in open country. The hairs on their light-colored fur are hollow, and can be controlled to lie flat and provide a protective shield against wind and water, or selectively raised to allow heat to escape. The bright white hairs on the rump can be raised and serve as an alarm signal that can be seen from great distances, much like the warning flag tail on our White-tailed Deer.

Pronghorn eye

Pronghorns have large eyes and long eyelashes

A Pronghorn feature that is quite noticeable are their large dark eyes with what seem like very long eyelashes. It turns out the long eyelashes help protect their eyes from the intense sun in their open habitat. When a pronghorn looks at you you really notice their large bulging eyes on the sides of their head.

Pronghorn face

Pronghorn face showing placement and size of eye

They have the largest sized eye of any North American ungulate in relation to their size with each eyeball measuring about 1 1/2 inches in diameter (about the size of the eye of a horse). The size and placement of their eyes gives them over a 300-degree arc of vision without moving their head, a useful trait for detecting potential predators at great distances. One reference said a Pronghorns’ vision is equivalent to that of a Peregrine Falcon and they may be able to detect movement up to 4 miles away.

Pronghorn doe and fawn

Pronghorns may once have been almost as numerous as Bison on the Great Plains. Their numbers were greatly reduced by over-hunting and by fences placed throughout their range, blocking their migration routes. While numbers in the West have increased through conservation efforts, there is still concern over the relatively small population of a few hundred Pronghorns in Yellowstone. Hopefully, ways can be found to protect the  Pronghorn migration routes to their wintering grounds outside the park so that future visitors can enjoy these incredible icons of the northern range.

Pronghorn boys club

Pronghorn bucks looking over a ridge

Babies everywhere

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It is spring in Yellowstone and there are babies everywhere, especially bison calves. Cute and frisky are the best words to describe these orange-furred bundles of energy – not the usual naturalist terms, but appropriate for these guys. And it has been a very good year for bison births – every herd has dozens of calves either frolicking or sacked out in the grass. And the sounds of being close to a herd are amazing – grunts and snorts, bawls of the calves, and even the munching of grass when they are close to your car.

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And there’s the promise of yet more babies to come. I’ve seen several pregnant pronghorn and mule deer. And then there are the nests – a bald eagle nest, a golden eagle nest, an osprey nest, and I’m sure many more yet to be discovered.

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But the most amazing thing I’ve seen was a pronghorn fawn. I just walked out onto a small hill to take a look at a distant bison herd. I didn’t even have my camera with me because I was only 20 yards from the car. But I looked down and right at the edge of the sage was a young pronghorn fawn doing what its’ instinct tells it to do – lie perfectly still to avoid predators. I took one quick picture with my phone and moved away so as not to disturb it. I looked around when I got back to the car and I could see two pronghorn females about 100 yards away, one of them undoubtedly the mother. In a week or two that little pronghorn will be able to run and avoid many of the predators out here in Lamar. Until then it will need to rely on camouflage and it’s relative lack of scent to avoid detection. I wish it well.