Pronghorn, Part I
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Cooler weather is at last beginning to arrive (although we’re back into the mid-90s today) and with it, comes new wildlife to photograph and new photo opportunities. Yesterday, I took advantage of the changing seasons and made a road trip with a friend, Sam Angevine, into the grasslands of southeastern Arizona.
It’s a whole different world at there. The area is not far from Tucson but its appearance and ecology is very different from our local desert. It is at a significantly higher elevation — the terrain varies from over 4,000 to more than 5,000 feet above sea level — and there are vast grasslands and some piñon pine, juniper, and oak forests in places. In appearance the area looks a lot more like Colorado or Wyoming east of the Rockies than the Sonoran Desert.
The area is home to an animal that I have long sought to photograph, the Pronghorn. These creatures, sometimes inaccurately called “Pronghorn Antelope” are leftovers from a time when America’s fauna was quite different from today’s animals. They are survivors from an era when this country’s grasslands and savannahs were populated with large grazing animals and big predators, a time when parts of North American resembled the plains of Africa.
I’ve been to the area more than once and I’ve never seen Pronghorn. They are relatively common in other parts of the western United States, but in southern Arizona the entire population is only about 250 individuals. There is a lot of grassland, several hundred square miles of it, and just a few Pronghorn. But, yesterday, Sam and I got lucky. We were driving a rural road when suddenly, Sam pointed out a small group of animals standing right next to the highway. It was a herd of about five Pronghorn. We immediately stopped and approached them. The animals ran off at first, but not too far, and then, they resumed their grazing and slowly drifted back in our direction.
Pronghorn are not very large, standing about four feet at the shoulder. They are unrelated to any other species — they are neither antelope nor deer, nor are they sheep or goats — but comprise the surviving members of a family of animals that is unique to North America.
They are the fastest land animals on earth, aside from the African Cheetah. Pronghorn evolved at a time when the land was stalked by big predators and they needed to be able to run in order to survive. A Pronghorn can attain a top speed of nearly 60 miles per hour — twice the speed of a galloping horse. It can run for hours at at time at 35 miles per hour. It has vision that is simply incredible by our standards. Supposedly, a Pronghorn can detect a moving object at a distance of several miles.
These Pronghorn were part of a little herd dominated by a male. The male (wearing a radio collar) stood watch over his harem. Early autumn is breeding season for these animals and the dominant males collect their harems and stay with them throughout the fall.
Males and females of the species have horns, with the males’ being larger than the females. They shed their horns each year (no other horned animal does so) after they breed. In these images the females have shed their horns, but new ones have already begun to regrow. The male is in the process of shedding.
Pronghorn have nearly vanished from southeastern Arizona. In a day or two I’ll talk about the efforts — not entirely uncontroversial — to reintroduce the species.
Images made with a Canon 5Diii, 400 DO + 1.4x Extender, M setting, ISO 640, f5.6 @ 1/640.