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45 autumn portraits of Pronghorn from Blacktail Plateau and Blacktail Ponds, between Mammoth Hot Springs and the Lamar Valley in Yellowstone National Park.
Most of the Yellowstone Wildlife images were prepared without Title Bars.
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Blacktail Plateau and Blacktail Ponds Lower Mammoth to Floating Island Lake
North Entrance and Lamar Valley
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The Banner below leads to the Pronghorn Gallery where images can be selected.
There are 165 images in the Pronghorn Gallery.
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Pronghorn Blacktail Plateau 0338
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Pronghorn Blacktail Plateau 0341
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A male Pronghorn poses atop a ridge on the Blacktail Plateau in northern Yellowstone National Park.
Pronghorn Blacktail Plateau 0340
Also called the Pronghorn Antelope, the Pronghorn is the only surviving member of the Family Antilocapridae and is not a true antelope, but it closely resembles the Old World antelope and fills a similar ecological niche. The Pronghorn can run exceptionally fast and it is considered to be the fastest land animal in North America. They evolved their running ability to escape from extinct predators such as the American Cheetah, and they are much faster than any current North American predators, being the second fastest land animal behind the Cheetah. Pronghorns can maintain high speeds much longer than cheetahs, and can reach 55 mph and can sustain this speed for a half mile. They can maintain 42 mph for 1 mile and 35 mph for 4 miles.
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Pronghorn Blacktail Plateau 0351
A male Pronghorn posing atop a ridge on the Blacktail Plateau in northern Yellowstone National Park.
Pronghorns are 4.5 feet to 5 feet long from nose to tail, stand about 3.5 feet tall at the shoulder, and have a barrel-shaped body. The males and females are about the same size, but females typically weigh about 20-25% less than males.
Pronghorns have dense, coarse, air-filled fur which provides excellent insulation. The dorsal fur is rufous brown, and they have off-white underbellies, rumps and neck patches. Males have dark patches of fur under the ears and a dark stripe running laterally between the horns. Both males and females have a dark patch on the nose, extending higher on the male to just under the eyes.
Pronghorns have very large eyes, a 320 degree field of view, and can discern detail at great distance.
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Pronghorns have unusual horns, which grow from two slender, laterally-flattened blades of bone in the front part of their skull. The horns are covered by skin which develops into a sheath of keratin. Unlike other mammals, a new sheath grows under the old one, which splits annually after the rut and is shed. The horns of the Pronghorn are unique in another way: the male horns curve backwards and fork in a forward-pointing tine (the prongs which give the species its name). The horn sheath of the male is 5”-17“ long, averaging about 10”. Females have much smaller straight horns which are very rarely pronged.
Horns differ from Antlers in several ways:
– Horns are a layer of Keratin (like fingernails and hair) over a living bony core. Antlers are true bone structures. – Horns are slow-growing and permanent (not shed each year). Antlers are fast-growing and are shed each year. – Horns are usually grown by both sexes. Antlers are usually grown only by males (except for caribou). – Horns are usually single tines, often curved or spiral, and exhibit annual growth rings indicating the age. – Antlers are associated with testosterone and are often branched. The number of tines do not indicate the age.
The image at right is a resized detail crop from 9968, which is shown further down the page in the section on Pronghorns at Blacktail Ponds. There is no larger version of this detail crop, but there is a larger version of the full image further below.
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Pronghorn Females Blacktail Plateau 0363
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Pronghorn Females Blacktail Plateau 0436
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Pronghorn females at Blacktail Plateau in northern Yellowstone National Park. The image above left was taken at distance early in the approach at 600mm. The image above right was taken later, from a closer distance at 300mm.
Pronghorns Blacktail Plateau 0370
A male Pronghorn and two females atop a ridge on Blacktail Plateau, taken early in the approach at 600mm.
Male Pronghorns defend territories from March through the end of the rut in early October. Bucks look for a territory with a water source and terrain features which allow them to corner females (does), and males with those features within their territory do better than those without. Some males defend their fixed territory and allow females to enter, while others defend a small harem of females and move. Males change their mating strategy depending on environmental conditions or demographic conditions. In areas where rainfall is higher, males tend to be territorial and mark the territory with scent from glands on either side of the jaw. They vocalize and challenge other males entering their territory. In areas where rainfall is lower, they tend to defend their harem and move from place to place, looking for water.
Females also have different mating stragegies. “Sampling” females visit several males, remaining with each for a while before switching to the next male. The rate at which they move increases as estrus approaches. “Inciting” females act as “samplers” until estrus, then they incite conflicts among males and mate with the winners of these battles. “Quiet” females remain with a single male in an isolated area throughout estrus. It appears that the “sampling” strategy is often energetically expensive, and that the “quiet” strategy is used by females with lower energy reserves.
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Pronghorns Blacktail Plateau 0391 16x9
A male and several female Pronghorns atop a ridge on the Blacktail Plateau, taken later in the approach at 420mm.
Pronghorns form mixed-sex herds in the winter, which disperse in the spring. Young males form bachelor herds, females group together, and adult males live alone, wandering in search of territory. These territories are usually widely spaced and do not overlap. The range size is smaller in the spring through fall than it is in the winter, when pronghorns wander farther for food.
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Pronghorns Blacktail Plateau 0392 16x9
Pronghorns eat mostly stems, leaves, shrubs and grasses, preferring to eat small amounts of a wide variety. They have a particular fondness for flowers, including spring flowers, daisies, paper flowers and woolly senecio. Paper flowers are poisonous to sheep, and woolly senecio are poisonous to cattle, but pronghorns can eat them.
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Pronghorns Blacktail Plateau 0394
A male and two female Pronghorns posing atop a ridge on the Blacktail Plateau in Yellowstone.
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The Banner below leads to the Pronghorn Gallery where images can be selected.
There are 165 images in the Pronghorn Gallery.
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Pronghorn Blacktail Plateau 0398 M
A male Pronghorn posing atop a ridge on the Blacktail Plateau in Yellowstone National Park.
All of the landscape (horizontal) large version images linked from the thumbnails are 1500 pixels wide. Portrait (vertical) images are 1200 pixels tall (1290 pixels with title bar). Images designated with an “M” in the shot number are 5:4 aspect ratio, 1500 x 1290 with a title bar, or 1500 x 1200 without a title bar. Some of the portrait images are also designated as “M”, and are 1500 pixels tall (plus the title bar).
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Pronghorn Females Blacktail Plateau 0407
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Pronghorn Females Blacktail Plateau 0431
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Pronghorn females on a ridge on the Blacktail Plateau in northern Yellowstone National Park.
Pronghorns Blacktail Plateau 0410
A Pronghorn male and two females on a ridge on the Blacktail Plateau in Yellowstone National Park.
The Pronghorn breeding period in Yellowstone is from mid-September to October and roughly corresponds to the Elk breeding period, making this a good time to visit.
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Pronghorns Blacktail Plateau 0411 M
A 1500 x 1290 image of a male and two female Pronghorn on a ridge on the Blacktail Plateau.
Pronghorn fawns and weak individuals are preyed upon by coyotes, wolves, mountain lions and other predators. Pronghorns can use their horns to defend against predators, and they can also use their sharply pointed hooves in defense, but their primary defenses are a 320 degree angle of view, exceptionally sharp eyesight, and speed. Pronghorns are capable of sprints of over 55 mph and can maintain speeds of 35 to 40 mph for long distances. The fastest measured sprint of a pronghorn is over 60 mph (the fastest cheetahs can reach 75 mph for 1.3 mile).
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Pronghorn Female Blacktail Plateau 0415 M
A 1500 x 1290 image of a female Pronghorn on a ridge on the Blacktail Plateau.
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Pronghorn Blacktail Plateau 0417
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Pronghorn Blacktail Plateau 0423
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A male Pronghorn raises its hackles and mane in response to the careful approach of the photographer.
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Pronghorn Blacktail Plateau 0424
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Pronghorn Blacktail Plateau 0428
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When a male Pronghorn is alarmed or disturbed it raises its hackles, an erectile patch of fur in front of its rump to alert others. The white hairs below can be seen for long distances. They also raise the mane hairs into a stiff brush, which communicates their alarm to nearby individuals. If the male determines that there is a threat, it warns the others by emitting a scent from glands in its rump and the pronghorns take off running.
Note in many of these closeups that the male has raised its hackles. As I approached, I moved in slowly and quietly, taking shots during the approach to accustom the Pronghorns to my presence and the sound of the shutter. While the Pronghorns were very aware of my presence, they did not consider me to be a threat and remained in their positions.
The male was somewhat concerned, because my student (who was just learning stalking techniques) occasionally made too much noise or moved a bit more rapidly than he should have, but he still did an exceptionally good job. In 300mm closeups I took from a similar distance on the Pronghorn 3 page, the male did not raise his hackles.
Pronghorn Females Blacktail Plateau 0440
A female Pronghorn checks out the photographer with the long black lens as he approaches. This image and many of the following images were taken at the end of the approach at 300mm.
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The Banner below leads to the Pronghorn Gallery where images can be selected.
There are 165 images in the Pronghorn Gallery.
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Pronghorn Females Blacktail Plateau 0444
300mm telephoto closeup of two female Pronghorns and a juvenile at Blacktail Plateau in Yellowstone.
Pronghorns in Yellowstone take part in the longest ungulate migration in the contiguous United States, from Grand Teton National Park to the Upper Green River Basin in Wyoming (the Path of the Pronghorn).
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Pronghorns Blacktail Plateau 0455
Getting very close to Pronghorns requires patience. They are curious animals, but they can be skittish. When you get inside 75 yards, you need to move very slowly and not make any sudden noises, thus it is a good idea to take shots as you approach to accustom them to the sound of the camera shutter. By the time you get to about 25 yards, they will be used to your presence, but if you go much closer they will flee, so getting good closeups requires a long telephoto lens and good stalking technique.
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Pronghorns Blacktail Plateau 0456
A 300mm telephoto closeup of male, female and juvenile Pronghorns at Blacktail Plateau in Yellowstone.
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Pronghorn Female Blacktail Plateau 0461
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Pronghorn Females Blacktail Plateau 0463
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300mm extreme telephoto closeups of a female Pronghorn at the close end of the approach on the Blacktail Plateau in Yellowstone.
Pronghorn Blacktail Plateau 0467 M
A 1000 x 1600 version of a 300mm extreme closeup of a male Pronghorn on the Blacktail Plateau in Yellowstone National Park.
Pronghorn limbs have evolved in specialized ways to increase their running ability, giving them exceptional speed and endurance. The formation of their foot allows them to stand on the tips of their hooves. The length of the radius bone is as long as (or longer than) the femur. The ulna and radius have been reduced to eliminate the twisting and rotating of the elbow, and the ulna is reduced and partially fused to the radius. The reduction of bone and associated muscles in the limbs decreases the limb weight, giving them more speed. Pronghorns have modified their joints to act as hinges, allowing only motion in the line of travel. This has been done by introducing interlocking spines and grooves in their joints. These adaptations have made pronghorns into exceptional runners, but they can no longer jump because they have lost their suspension mechanism.
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Pronghorn Blacktail Plateau 0466c
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Pronghorn Blacktail Plateau 0470
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Extreme closeups of a male Pronghorn on the Blacktail Plateau in Yellowstone National Park.
The Banner below leads to the Pronghorn Gallery where images can be selected.
There are 165 images in the Pronghorn Gallery.
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Pronghorn Female Blacktail Plateau 0472
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Pronghorn Female Blacktail Plateau 0473
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Pronghorn Female and Juvenile Blacktail Plateau 0475
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Pronghorn Female and Juvenile Blacktail Plateau 0477
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300mm closeups of a Pronghorn female and juvenile on Blacktail Plateau in Yellowstone National Park.
Pronghorn Female and Juvenile Blacktail Plateau 0483
300mm closeup of a Pronghorn female and a juvenile playing peek-a-boo on Blacktail Plateau in Yellowstone.
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Pronghorn Female Blacktail Plateau 0487
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Pronghorn Female Blacktail Plateau 0492
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Pronghorn Female Blacktail Plateau 0491
A 300mm closeup of a smiling female Pronghorn on Blacktail Plateau in Yellowstone National Park.
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Pronghorn Blacktail Plateau 0495
One final 300mm close portrait of a male Pronghorn on the Blacktail Plateau in Yellowstone.
This was an exceptionally close approach, and what was more remarkable is that I took a student in on this approach. I was most impressed in the student’s ability to stalk quietly and maintain his calm.
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The Banner below leads to the Pronghorn Gallery where images can be selected.
There are 165 images in the Pronghorn Gallery.
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Pronghorn at Sunrise Blacktail Ponds 8836
A male Pronghorn near Blacktail Ponds at sunrise, taken from very close range at 200mm.
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Pronghorn at Sunrise Blacktail Ponds 8840
This fellow wandered up close to see what we were doing. I have to tell you that having a Pronghorn approach you to about 20 yards is somewhat unusual. I was working with a different student this day, and he was so shocked by the appearance of the Pronghorn that he stood flabbergasted and did not take any shots. I rapidly switched from one camera body (on the 500mm) to the other (200mm) to take these because the image from the 500mm would have been an extreme close portrait from the neck up.
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Pronghorn Blacktail Ponds 9960
A 420mm scenic shot of a male Pronghorn looking over Blacktail Ponds in northern Yellowstone.
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Pronghorn Blacktail Ponds 9962
A closer shot of the male Pronghorn at Blacktail Ponds, taken at 600mm.
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Pronghorn Blacktail Ponds 9966
This fellow also came close to see what we were doing. Did I mention that Pronghorns were curious? This image of a male Pronghorn at Blacktail Ponds was taken from about 30 yards with a 300mm lens.
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Pronghorn Blacktail Ponds 9971
The male Pronghorn passes even closer (about 25 yards) without stopping and watches the humans.
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Pronghorn Blacktail Ponds 9973
At the edge of the clearing, the Pronghorn pauses for a portrait before running into the valley at high speed.
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The Banner below leads to the Pronghorn Gallery where images can be selected.
There are 165 images in the Pronghorn Gallery.
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Click the Display Composite above to visit the Pronghorns: Lower Mammoth to Floating Island Lake page.
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Click the Display Composite above to visit the Pronghorns: North Entrance and Lamar Valley page.
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