Dubois, WY 2018
Group Photo
Our guide and Executive Director of the Big Horn Sheep Association, Sara Domek, with John Gilbert, and Bob Colvin on Whiskey Mountain.
Ram #6
A characteristic of the Rams is raising their heads, pulling back their lips in search of estrus. A ewe in heat (estrus) will generally seek out the ram. She will sniff and chase after him. The ram responds to urination by the estrus ewe by sniffing, extending the leg, and curling his lip. Curling the lip is called the "flehmen response." If the female is receptive, she will stand for mating. The ram may fail in several initial attempts to mount the ewe. He may repeatedly mate the same ewe.
Ram #7
It's not just the size of your horns, but having the experience to know how to use them. Scientists have studied the effects of trophy hunting on bighorn sheep with alarming results: human selection is leading to artificial evolution, resulting in smaller horn size.
"We have been wondering what influence selective hunting has on the evolution of a species," says David Coltman, professor of biological sciences at the University of Alberta. "What you have here is clearly artificial selection. You can imagine that harvested animals don't have any more offspring. Their genes are removed from the gene pool." Coltman recalls Darwin's observation that the system of killing only the finest stags on Scottish estates may cause red deer to degenerate. Ironically, hunting based on minimum size criteria—such as horn size—selects against the trait most desired by hunters: the size of the trophy.
"Conventional wisdom is that the bigger your horns are, the better you do because you're better armed than the competition," says Coltman. "This is partially true, but it's quite age-dependent. It's not just the size of your horns, but also how old you are. For a ram to become highly successful and socially dominant, he's not just large-horned. He's also experienced." Rams are often shot prior to reaching that age of experience. "It doesn't take a big stretch as an evolutionary biologist to recognize that this is strong selection pressure."
Dominant rams reach their peak reproductive years at age eight to 10, long after their horns reach the legal age for trophy hunting, which in Alberta is currently a four-fifths curl, when the tip of the horn is parallel with the eye.
Coltman and his colleagues on the study—Gabriel Pigeon, Marco Festa-Bianchet, and Fanie Pelletier from the University of Sherbrooke—concentrated on data collected from bighorn sheep on Ram Mountain near Nordegg, Alberta. Their analysis of 39 years' worth of data collected on the sheep that were subject to intense trophy hunting for 23 of those years supports the contention that selective hunting led to a reduction in horn length through evolutionary change.
"For 30 years in Alberta, the number of trophy rams has been declining, and the age of these legal rams is increasing. This signals that what we are seeing at Ram Mountain may be true across wider areas." Coltman says there are many more licences issued to trophy hunters than there are available legal rams.
"What we see is a decline in horn size over time," he says, noting the average size of a set of horns at Ram Mountain has declined more than 20 per cent over 43 years.
Another startling result from the study is that after artificial selection stops, recovery of horn length through natural selection is slow. "You can't imagine a stronger selection pressure than hunting based on a measurable morphometric trait," Coltman emphasizes. "What we have here is a very hard-edged selection. We simply need to reduce the selective edge by taking fewer rams or re-examining size requirements. If we stop hunting based on horn size, the horn size will increase, albeit slowly. We have to be more evolutionarily enlightened about how we manage and conserve animal populations."
Coltman's research focuses on the maintenance and adaptive significance of genetic variation in the wild. He also tests evolutionary theory in natural populations using longitudinal data and pedigrees and applies genetic methods to problems in conversation and wildlife management. He has been involved with the pedigree work and genetics of the Ram Mountain bighorn sheep population since 1999.
Read more at: https://phys.org/news/2016-01-intense-trophy-artificial-evolution-horn.html#jCp
Ram #8
A characteristic of the Rams is raising their heads, pulling back their lips in search of estrus. A ewe in heat (estrus) will generally seek out the ram. She will sniff and chase after him. The ram responds to urination by the estrus ewe by sniffing, extending the leg, and curling his lip. Curling the lip is called the "flehmen response." If the female is receptive, she will stand for mating. The ram may fail in several initial attempts to mount the ewe. He may repeatedly mate the same ewe.
Torrey Lake
Torrey Lake is a natural lake and part of what is termed the "3 lakes" area near Dubois. The other two lakes in this group are Ring and Trail lakes. These lakes are on Torrey Creek which is a tributary to the Wind River. The nearby Whiskey Basin was a favorite winter ground for the Sheepeater Clan of the Shoshone Tribe because of the relatively mild winters and the abundance of big game.
Ram #9
Unlike deer, elk and moose, which shed their antlers every winter and start growing new ones every spring, the horns on bighorns remain intact and continue to grow as they age. Full-curl rams are considered to be dominant members of bighorn sheep society and the butting of heads during the mating season is legendary. “Full curl” means that their horns complete a 360-degree circle when viewed from the side, reaching or surpassing their eyes. A ram can weigh over 300 pounds and stand 42 inches tall at the shoulders.
Ewe #2
The bighorn sheep (Ovis canadensis), are well-known for their impressive horns and their incredible agility on the steep crags of the Rockies. Neither of these attributes, unfortunately, could protect the sheep from the threat of the introduction of domestic sheep, which carried disease for which the native species lacked resistance, and an insatiable appetite for the bighorn's primary diet. Bighorn populations fluctuated between the 1800s and 1940s; by the late 1950s, the sheep had disappeared from lower elevations. Several factors contributed to the bighorn sheep's revival. Domestic sheep were removed from ranges outside the park, opening that land for use by bighorn sheep and reducing the danger of contracting disease. The National Park Service began controlling human access to critical bighorn areas and introduced the bighorn to low- elevation winter ranges. Certain trails are now closed during lambing season, and the natural mineral lick at Horseshoe Park, which the bighorn depend on, is kept clear of enthusiastic visitors who may distress the animals.
Ewe #4
Bands of Ewes graze together. They are sure footed and very agile. Bighorn sheep eat different foods depending on the season. During the summer, they subsist on grasses or sedges. During the winter they eat more woody plants, such as willow, sage and rabbit brush. Desert bighorn sheep eat brushy plants such as desert holly and desert cactus.
Ewe #5
Bighorn sheep were once widespread throughout western North America. By the 1920’s, bighorn sheep were eliminated from Washington, Oregon, Texas, North Dakota, South Dakota, Nebraska, and part of Mexico. Today, populations have been re-established through transplanting sheep from healthy populations into vacant places.
Mule Deer #1
Mule deer and black-tailed deer (collectively called mule deer, Odocoileus hemionus) are icons of the American West. They are distributed throughout western North America from the coastal islands of Alaska, down the West Coast to southern Baja Mexico and from the northern border of the Mexican state of Zacatecas, up through the Great Plains to the Canadian provinces of Saskatchewan, Alberta, British Columbia and the southern Yukon Territory.
Mule Deer #2
Mule deer are primarily browsers, with a majority of their diet comprised of forbs (weeds) and browse (leaves and twigs of woody shrubs).
Deer digestive tracts differ from cattle and elk in that they have a smaller rumen in relation to their body size, so they must be more selective in their feeding. Instead of eating large quantities of low-quality feed like grass, deer must select the most nutritious plants and parts of plants.
Because of this, deer have more specific forage requirements than larger ruminants.
Mountain Lion Track
Mountain Lions are in this area as witnessed by this lion track. Mountain lions have a distinctive "M" shaped pad with three lobes on the rear of the heel (dogs only have two lobes). Their claw marks do not show in the track. Our guides informed us of two wolf packs on Torrey Rim that merged into one pack. Mountain lions are solitary animals. They are very territorial and actively avoid other cats except during courtship. Their ranges can vary in size from 10 square miles to around 370 square miles; females tend to have smaller ranges than males. Mountain lions are active hunters and may travel long distances in search of food. They hunt alone and attack from behind, breaking the neck of their prey by biting it at the base of the skull. After killing their prey, they will bury it and leave it, coming back to feed on it when hungry. They have long been persecuted and hunted as a threat to livestock. Current threats also include habitat loss and poaching. Despite being listed for 38 years as a game mammal, and decades of publicly funded research, the State of Wyoming refuses to openly announce a population estimate on the number of lions existing within its borders. Some have opined that this policy stance is an effort to avoid having to justify an ever increasing hunting quota, and wildlife management decisions which enrich a few ranchers at the expense of the species. (Mountain Lion Foundation)
Since 2007, Wyoming Game and Fish has been successfully reducing the state's mountain lion population in an attempt to bolster mule deer numbers. The number of mountain lions killed by hunters increased from 180 in 2006 to 306 in 2013, and has leveled off or decreased slightly since 2013. During this same time period, the proportion of older trophy male mountain lions killed by hunters each year has decreased, while the proportion of females and younger males killed has increased.
This change in harvest proportions points towards one hard truth: a population in decline. Hunters prefer large, prime-aged male mountain lions. When there are fewer mature male mountain lions in the population, hunters shift to killing the demographic groups that remain, namely younger animals and females. The demographic shifts in hunter-caught individuals are likely reflective of changes in the population structure as a whole. Fewer mature resident males, heavier harvest pressure on other age groups, and higher female mortality all lead to declining mountain lion numbers. Further compounding the influence of overharvest, hunting females is particularly problematic to maintaining a viable population because they are the ones who raise the kittens.
Exactly how hunting influences the population trajectory is no mystery. Local research led by the Teton Cougar Project shed new light on the influence hunting has on the state's mountain lion population. They found that the study area's mountain lion population declined by nearly fifty percent over the last decade, and that reducing the hunting limit in the unit from five to three animals could halt that decline. (Mountain Lion Foundation)
Mule Deer #3
Mule deer are generally easy to identify due to their large mule-like ears (generally 3/4 the length of the head).
They usually have a distinctive black forehead, or mask, that contrasts sharply with a light grey face. The lighter facial coloration makes the eye rings and muzzle markings seem less obvious.
Mule deer are brownish-gray in color, have a white rump patch and a small white tail with a black tip.
Ram #11
The reason for their dexterity comes largely with the design of their hooves.
“They are a little bit different than say a deer or elk or other cloven-hooved animals,” Kanta said. “Sheep have hooves that are fatter and wider, and on the bottom of them, it’s more of a soft pad. I call it a suction cup, which really isn’t a good description, but I say that, because it helps them grab the rock and stick to the rock versus a hard hoof that would slip on the rock.” As the sheep step down, the pad grips the rock while the outside of the hoof remains ridged. (John Kanta, regional wildlife manager for the South Dakota, Game, Fish, and Parks).
Ram #12
Bighorn sheep were among the most admired animals of the Apsaalooka (Crow) people, and what is today called the Bighorn Mountain Range was central to the Apsaalooka tribal lands. In the Bighorn Canyon National Recreation Area book, storyteller Old Coyote describes a legend related to the bighorn sheep. A man possessed by evil spirits attempts to kill his heir by pushing the young man over a cliff, but the victim is saved by getting caught in trees. Rescued by bighorn sheep, the man takes the name of their leader, Big Metal. The other sheep grant him power, wisdom, sharp eyes, sure-footedness, keen ears, great strength, and a strong heart. Big Metal returns to his people with the message that the Apsaalooka people will survive only so long as the river winding out of the mountains is known as the Bighorn River. (Wikipedia)
Ram #13
Bighorn sheep were among the most admired animals of the Apsaalooka (Crow) people, and what is today called the Bighorn Mountain Range was central to the Apsaalooka tribal lands. In the Bighorn Canyon National Recreation Area book, storyteller Old Coyote describes a legend related to the bighorn sheep. A man possessed by evil spirits attempts to kill his heir by pushing the young man over a cliff, but the victim is saved by getting caught in trees. Rescued by bighorn sheep, the man takes the name of their leader, Big Metal. The other sheep grant him power, wisdom, sharp eyes, sure-footedness, keen ears, great strength, and a strong heart. Big Metal returns to his people with the message that the Apsaalooka people will survive only so long as the river winding out of the mountains is known as the Bighorn River. (Wikipedia)
Mule Deer #4
Mule deer range from 3 to 3-1/2 feet tall at the shoulder, 4-1/2 to 7 feet long and have a tail that is 5 to 8 inches long. They can weigh between 130-280 pounds. The female deer are smaller than the male. Because the eyes of mule deer are located on the sides of their heads, they can see a 310 degree view around themselves. They have better nighttime vision than humans, but less accurate daytime and color vision.
Mule deer can detect slight predator movement up to 600 meters away, but they are not very good at detecting motionless forms. Mature mule deer bucks have antlers with main beams that sweep outward and upward, forking once and then forking again. Brow tines are not always present. Mature bucks typically have eight to 10 total points (including brow tines that exceed one inch). These bucks are considered 4-point bucks (the number of points on one side of the rack excluding the brow tines).
Ram #14
Many bighorn sheep populations in the United States experience regular outbreaks of infectious pneumonia which likely result from the introduction of bacterial pathogens carried in domestic sheep. Once introduced, pathogens can transmit rapidly through a bighorn population, resulting in all-age die-offs that sometimes kill up to 90% of the population. In the years following pathogen introduction, bighorn populations frequently experience multiple years of lamb pneumonia outbreaks. These outbreaks can severely limit recruitment and likely play a powerful role in slowing population growth. Big Horn Sheep which come in contact with domestic sheep can be euthanized by conservation agents to prevent the spread of pneumonia.(Wikipedia and Big Horn Sheep Center)
Petroglyphs
Whiskey Basin Wildlife Habitat Management Area is four miles east of Dubois off U.S. Highway 26/287. The 12,782-acre area was established in 1954 to provide crucial winter range for bighorn sheep. In fact, Whiskey Basin is home for 1,200 bighorns, the largest herd in the world. A camp on the area serves as the site for the Wyoming Game & Fish Department-sponsored annual youth and teachers conservation camps.
Whiskey Basin was a favorite winter ground for the Sheepeater Clan of the Shoshone Tribe because of the relatively mild winters and the abundance of big game. Petroglyphs carved in the large glacial rocks by the Sheepeaters provide a vivid history of this area. These petroglyphs are irreplaceable treasures.
Big Horn Owl
The great horned owl, also known as the tiger owl (originally derived from early naturalists' description as the "winged tiger" or "tiger of the air") or the hoot owl, is a large owl native to the Americas. It is an extremely adaptable bird with a vast range and is the most widely distributed true owl in the Americas. Its primary diet is rabbits and hares, rats and mice, and voles, although it freely hunts any animal it can overtake, including rodents and other small mammals, larger mid-sized mammals, birds, reptiles, amphibians, and invertebrates.
Hunting activity tends to peak between 8:30 pm and 12:00 am at night and then can pick back up from 4:30 am to sunrise. Hunting activity tends to be most prolonged during winter by virtue of prey being scarcer. Almost all prey are killed by crushing with the owl's feet or by incidentally stabbing of the talons, though some may be bitten about the face as well. Prey is swallowed whole when possible. When prey is swallowed whole, owls regurgitate pellets of bone and other non-digestible bits about 6 to 10 hours later, usually in the same location where the prey was consumed. Great horned owl pellets are dark gray or brown in color and very large, 7.6 to 10.2 cm (3.0 to 4.0 in) long and 3.8 cm (1.5 in) thick, and have been known to contain skulls up to 3 cm (1.2 in) in width inside them. However, not all prey can be swallowed at once, and owls will also fly with prey to a perch and tear off pieces with their bill. Most dietary studies focus on pellets found under perches and around nests, since they provide a more complete picture of the diversity of prey consumed, but prey remains outside of pellets may provide clues to prey excluded from the pellets and a combination of both is recommended. Many large prey items are dismembered. Great horned owls may behead large prey before taking it to its nest or eating perch. (Wikipedia)
Ram #16
The Lander region Whiskey Mountain bighorn sheep population was once again alarmingly low at 8/100 in 2017 and lamb production continues to be a grave concern. The nearby Darby Mountains also saw population declines.
As bighorn sheep herds continue to falter across the West, states search for ways to prevent the massive die-offs. For Wyoming, that means focusing on the Whiskey Mountain herd—a bighorn sheep herd that has been struggling for decades. In May, the U.S. Department of the Interior announced that 1,431 acres of winter range would be set aside for this herd in hopes that providing critical habitat would help the herd rebound. Now, Wyoming Game and Fish Department (WGFD) officials are partnering with the Wyoming Wild Sheep Foundation, the National Bighorn Sheep Interpretive Center and the University of Wyoming’s Ruckleshaus Institute “to explore management concerns, issues and opportunities” for the Whiskey Mountain bighorn sheep herd, Buckrail reports.
This iconic herd experienced a massive die-off linked to pneumonia in 1990 and 1991, which decimated nearly half of the herd. Today’s herd is estimated at only about 850 animals, which is nearly 40% under the 1,350-sheep goal set by the state. Biologists believe that the cause is a combination of high fawn mortality coupled with poor nutrition, hence the Interior’s decision to renew the mineral withdrawal for critical winter range. (K. A Schmitt, Go Hunt News, June 2018)
Ram #17
The Lander region Whiskey Mountain bighorn sheep population was once again alarmingly low at 8/100 in 2017 and lamb production continues to be a grave concern. The nearby Darby Mountains also saw population declines.
As bighorn sheep herds continue to falter across the West, states search for ways to prevent the massive die-offs. For Wyoming, that means focusing on the Whiskey Mountain herd—a bighorn sheep herd that has been struggling for decades. In May, the U.S. Department of the Interior announced that 1,431 acres of winter range would be set aside for this herd in hopes that providing critical habitat would help the herd rebound. Now, Wyoming Game and Fish Department (WGFD) officials are partnering with the Wyoming Wild Sheep Foundation, the National Bighorn Sheep Interpretive Center and the University of Wyoming’s Ruckleshaus Institute “to explore management concerns, issues and opportunities” for the Whiskey Mountain bighorn sheep herd, Buckrail reports.
This iconic herd experienced a massive die-off linked to pneumonia in 1990 and 1991, which decimated nearly half of the herd. Today’s herd is estimated at only about 850 animals, which is nearly 40% under the 1,350-sheep goal set by the state. Biologists believe that the cause is a combination of high fawn mortality coupled with poor nutrition, hence the Interior’s decision to renew the mineral withdrawal for critical winter range. (K. A Schmitt, Go Hunt News, June 2018)
Ram #18
The Lander region Whiskey Mountain bighorn sheep population was once again alarmingly low at 8/100 in 2017 and lamb production continues to be a grave concern. The nearby Darby Mountains also saw population declines.
As bighorn sheep herds continue to falter across the West, states search for ways to prevent the massive die-offs. For Wyoming, that means focusing on the Whiskey Mountain herd—a bighorn sheep herd that has been struggling for decades. In May, the U.S. Department of the Interior announced that 1,431 acres of winter range would be set aside for this herd in hopes that providing critical habitat would help the herd rebound. Now, Wyoming Game and Fish Department (WGFD) officials are partnering with the Wyoming Wild Sheep Foundation, the National Bighorn Sheep Interpretive Center and the University of Wyoming’s Ruckleshaus Institute “to explore management concerns, issues and opportunities” for the Whiskey Mountain bighorn sheep herd, Buckrail reports.
This iconic herd experienced a massive die-off linked to pneumonia in 1990 and 1991, which decimated nearly half of the herd. Today’s herd is estimated at only about 850 animals, which is nearly 40% under the 1,350-sheep goal set by the state. Biologists believe that the cause is a combination of high fawn mortality coupled with poor nutrition, hence the Interior’s decision to renew the mineral withdrawal for critical winter range. (K. A Schmitt, Go Hunt News, June 2018)
Pronghorns
Fleet-footed pronghorns are among the speediest animals in North America. They can run at more than 53 miles an hour, leaving pursuing coyotes and bobcats in the dust. Pronghorns are also great distance runners that can travel for miles at half that speed.
Pronghorns are about three feet tall at the shoulders. They are reddish brown, but feature white stomachs and wide, white stripes on their throats. When startled they raise the hair on their rumps to display a white warning patch that can be seen for miles.
Both sexes sport impressive, backward-curving horns. The horns split to form forward-pointing prongs that give the species its name. Some animals have horns that are more than a foot long.
Like other even-toed hoofed animals, pronghorns chew cud—their own partially digested food. The meal of choice for this speedy herbivore is generally grass, sagebrush, and other vegetation.
Pronghorns mate each fall in the dry, open lands of western North America. Bucks gather harems of females and protect them jealously—sometimes battling rivals in spectacular and dangerous fights. In the spring, females give birth to one or two young, which can outrun a human after just a few days.
Pronghorns are hunted throughout much of their natural range, but some subspecies are endangered.
Mule Deer Doe
Mule deer usually live 9-11 years in the wild and can live to be much older when in captivity. Mule deer are primarily browsers, with a majority of their diet comprised of forbs (weeds) and browse (leaves and twigs of woody shrubs).
Deer digestive tracts differ from cattle and elk in that they have a smaller rumen in relation to their body size, so they must be more selective in their feeding. Instead of eating large quantities of low-quality feed like grass, deer must select the most nutritious plants and parts of plants.
Mule Deer Does
Because the eyes of mule deer are located on the sides of their heads, they can see a 310 degree view around themselves. They have better nighttime vision than humans, but less accurate daytime and color vision.
Mule deer can detect slight predator movement up to 600 meters away, but they are not very good at detecting motionless forms.
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