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Fitness and Photography for Fun - A blog on staying fit by hiking and doing photography by David Mendosa


October 10th, 2014 · 4 Comments

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Because ​the P​ronghorn ​is​ the only mammal that ​can eat ​much ​sagebrush, ​it is to me the ultimate animal of the American West and the Great Plains.​ ​To me sagebrush is a prime symbol of the ​land that I ​call home and ​love. But to ​the ​Pronghorn it is even more. It’s their diet.
No other large animal can tolerate eating much sagebrush. That’s because ​the Pronghorn are the only one that evolved along with that plant. it is the sole surviving member of an ancient family dating back 20 million years.​ ​Other large herbivores are more recent arrivals from Asia. That makes ​the ​Pronghorn another truly Western icon.

“Although pronghorns are native to grasslands, they do not eat very much grass,” writes Candace Savage in​ Prairie: A Natural History. “In lieu of grass, pronghorns prefer a diet of shrubs and forbs, using their small, dainty muzzles to nip off the choicest morsels. This ability to forage selectively, one mouthful at a time, is important because many of the pronghorns’ favorite foods are laced with poison…sage and sagebrush contain turpentinelike compounds…Cattle avoid sages, and even mule deer can’t eat too much, but pronghorns have completely mastered the challenge. Sage and sagebrush are among their staple foods and feature in their diet throughout the year.”

The Pronghorn diet isn’t obvious, but their prongs are. ​The most noticeable ​Pronghorn​ characteristic​ is also the source of their common name. Both males and females have a pair of short horns on the top of the head. ​Females ​have small ​horns​, usually only ​the size of ​a bump. ​But ​the horns of ​males​ are a​bout 10​ to ​12 inches long. The​ir shape is unique because​ they point backwards.​

We saw a Pronghorn couple on the afternoon of the first of three days that Sharon and I were at Pawnee National Grassland. Even though the sky was overcast, I like this shot because it epitomizes the protection that a male Pronghorn offers to its female.

​​​​A Curious Pronghorn Pair

A Curious Pronghorn Pair

Click on the picture above to enlarge

That timing of this photograph could have been better, and timing is a key to nature photography. We learn timing with experience, which is why going back to the same place again and again is important. As Sharon and I drove the roads of the Pawnee Grassland we kept noticing a Pronghorn herd a few miles north of the Crow Valley Campground along Weld County Road 77. Since they were to the west of the road, that meant a morning shot to have the light at my back.

Just as the sun rose at 6:41 a.m. on the final day of our visit to the grassland we approached the herd. I knew that the Pronghorn would run away fast when we stopped, so I was ready when we saw this buck at 6:49 a.m.

​​Off He Goes!

Off He Goes!

Click on the picture above to enlarge

​While Pronghorn are curious animals, they must love running more. “Pronghorn run far better than any human and in fact run better than almost any animal ever to roam the earth, now or in the deep past,” writes John A. Byers in Built for Speed: A Year in the Life of Pronghorn. “Pronghorn are unquestionably the fastest mammal in North America. They accelerate explosively from a standing start to quickly reach a top speed close to 60 miles per hour. Pronghorn also can cruise at 45 miles per hour for several miles. Unlike cheetahs or human racers, pronghorn are built both for sprints and for distance running.”​

Four minutes after than this buck sped away from us, I was able to photograph 11 females also running. But I was especially lucky because in this case their course was parallel to us.

​​​The Herd is On the Move

The Herd is On the Move

Click on the picture above to enlarge

These are photographs of Pronghorn. Not of Antelope. The Pronghorn isn’t closely related to the ​A​ntelope​ of Africa​, ​although ​people often call it one, and it fills a similar ecological niche due to convergent evolution.​ Even its scientific name, Antilocapra americana, which means North American antelope-goat, doesn’t make sense. While it has some similarities to both antelope and goats, the ​P​ronghorn is neither.​​ ​The Pronghorn is the only animal in the world with branched horns and the only animal in the world to shed its horns as if they were antlers.

In his wonderful book University of Idaho Professor Byers​ perfectly captures the way I feel about this land of the Pronghorn. “When I walk where there are a few scattered trees,” ​he writes, ​”​I have the deeply relaxing sensation that I am home. And that is not because I grew up in grassland​ ​…​ ​Many biologist have noted that a deep emotional response to grassland makes sense from an evolutionary perspective, because grassland dotted with trees is the environment where our species came into being.”​ We are truly home on the range.​


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Posted in: Photography

4 responses so far ↓

  • 1 Gretchen // Oct 10, 2014 at 4:48 am

    “. . it epitomizes the protection that a male Pronghorn offers to its female.”

    Either that, or he just wanted to make sure he was the most prominent in the photo.

    Gorgeous photos.

  • 2 David Mendosa // Oct 10, 2014 at 10:07 am

    Are you sure that you aren’t just projecting?

  • 3 Gretchen // Oct 10, 2014 at 11:02 am

    Well, maybe. Every time I’ve had my photo taken with a pronghorn, I’ve tried to make sure I was most prominent. Of course, I’ve never had my photo taken with a pronghorn, so it didn’t work.

  • 4 David Mendosa // Oct 10, 2014 at 12:35 pm

    I applaud your consistency, Gretchen. Of course, Emerson wouldn’t agree. I’m sure you know that he said “A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines.” Are you consistent because you are divine?