The pronghorn is a species of artiodactyl mammal indigenous to interior western and central North America. Though not an antelope, it is known colloquially in North America as the American antelope, prong buck, pronghorn antelope, prairie antelope, or antelope because it resembles the true antelopes of the Old World and fills a similar ecological niche due to parallel evolution, it is the only surviving member of the family Antilocapridae. During the Pleistocene epoch, about 12 antilocaprid species existed in North America. Three other genera existed when humans are now extinct; as a member of the superfamily Giraffoidea, the pronghorn's closest living relatives are the giraffes and okapi. The Giraffoidea are in turn members of the infraorder Pecora, making pronghorns more distant relatives of the Cervidae and Bovidae, among others; the scientific name of the pronghorn is Antilocapra americana. The pronghorn is the sole extant member of the family Antilocapridae; this species was first described by American ornithologist George Ord in 1815.
The pronghorn were first seen and described by Spanish explorers in the 16th century, but were not formally recorded or scrutinised till the 1804–1806 expedition by Captain Meriwether Lewis and Second Lieutenant William Clark. The expedition, which aimed to unravel water routes in the continent for commercial purposes, led to the discovery or formal recognition of a variety of flora and fauna of North America. Following the discovery of a few subspecies of the sharp-tailed grouse and Clark came across the pronghorn near the mouth of the Niobrara River, in present-day Nebraska. Clark was the first to kill a pronghorn, described his experience as follows: I walked on shore to find an old Vulcanoe... in my walk I killed a Buck Goat of this Countrey, about the height of the Grown Deer, its body Shorter the horns, not hard and forks 2⁄3 up one prong Short the other round & Sharp arched, is above its Eyes the Color is a light gray with black behind its ears down the neck, its face white round its neck, its Sides and its rump round its tail, Short & white.
Lewis and Clark made several other observations on the behavior of the pronghorn and how the local tribes hunted them. They described the animal, which they referred to as the "Antelope" or the "Goat", as follows: Of all the animals we have seen the Antelope seems to possess the most wonderful fleetness. Shy and timorous they repose only on the ridges, which command a view of all the approaches of an enemy... When they first see the hunters they run with great velocity... The Indians near the Rocky Mountains hunt these animals on horseback, shoot them with arrows; the Mandans' mode of hunting them is to form a large, strong pen or fold, from which a fence made of bushes widens on each side. The animals are surrounded by the hunters, driven towards this pen, in which they imperceptibly find themselves enclosed, are at the mercy of the hunters. Pronghorns have distinct white fur on their rumps, breasts and across their throats. Adult males are 1.3–1.5 m long from nose to tail, stand 81–104 cm high at the shoulder, weigh 40–65 kg.
The females weigh 34 -- 48 kg. The feet have two hooves, with no dewclaws, their body temperature is 38 °C. The orbits are prominent and set high with never an anteorbital pit, their teeth are hypsodont, their dental formula is 0.0.3.33.1.3.3. Each "horn" of the pronghorn is composed of a slender, laterally flattened blade of bone that grows from the frontal bones of the skull, forming a permanent core; as in the Giraffidae, skin covers the bony cores, but in the pronghorn, it develops into a keratinous sheath, shed and regrown annually. Unlike the horns of the family Bovidae, the horn sheaths of the pronghorn are branched, each sheath having a forward-pointing tine. Males have a horn sheath about 12.5–43 cm long with a prong. Females have smaller horns that range from 2.5–15.2 cm and sometimes visible. Males are further differentiated from females in having a small patch of black hair at the angle of the mandible. Pronghorns have a musky odor. Males mark territory with a preorbital scent gland, on the sides of the head.
They have large eyes with a 320° field of vision. Unlike deer, pronghorns possess a gallbladder; the pronghorn is the fastest land mammal in the Western Hemisphere, being built for maximum predator evasion through running. The top speed is hard to measure and varies between individuals, it is cited as the second-fastest land animal, second only to the cheetah. It can, sustain high speeds longer than cheetahs. University of Idaho zoologist John Byers has suggested the pronghorn evolved its running ability to escape from extinct predators such as the American cheetah, since its speed exceeds that of extant North American predators. Compared to its body size, the pronghorn has a large windpipe and lungs to allow it to take in large amounts of ai
Rocky Mountain elk
The Rocky Mountain elk is a subspecies of elk found in the Rocky Mountains and adjacent ranges of Western North America. The winter ranges are most common in open forests and floodplain marshes in the lower elevations. In the summer it migrates to alpine basins. Elk have a diverse habitat range that they can reside in but are most found in forest and forest edge habitat and in mountain regions they stay in higher elevations during warmer months and migrate down lower in the winter, they may come down the mountain and leave the forest into some grassland for part of the day but head back into the timber in the evening. The total wild population is about one million individuals; the Rocky Mountain elk was reintroduced in 1913 to Colorado from Wyoming after the near-extinction of the regional herds. While overhunting is a significant contributing factor, the elk’s near-extinction is attributed to human encroachment and destruction of their natural habitats and migratory corridors. A year twenty-one elk from Jackson Hole, Wyoming were reintroduced to South Dakota's Wind Cave National Park for population increase.
Conservation efforts brought the elk populations in New Mexico from near zero numbers in the late 1800s and early 1900s, to healthy populations in the 1930s in Northern New Mexico. Population numbers of elk in Nebraska continued to increase through the 1970s and 1980s, to a level in which complaints from landowners in the Pine Ridge region led to the implementation of liberal hunting seasons in the late 1980s. Elk numbers continued to increase through the 1990s to the present. All Rocky Mountain elk in Washington are the result of reintroductions conducted in the early 1900s from Yellowstone elk herds; these initial reintroductions have expanded their range and have been translocated within the State. Not all of these elk have all the habitat to be successful in large numbers. In 1990, feasibility studies were conducted to determine if wild, free-ranging elk still had a place in some of their former eastern haunts. Once this was complete, healthy source herds of Rocky Mountain elk from Arizona, New Mexico, North Dakota and Utah were used to introduce this elk subspecies to the former eastern elk range.
In recent years, elk from Utah have been used to reestablish a population in Kentucky. As of 2010, the Rocky Mountain elk herd has been diagnosed with a serious disorder called Chronic Wasting Disease. CWD affects the brain tissue of infected elk and is similar in symptoms to bovine spongiform encephalopathy known as mad-cow disease. There is no evidence to conclude that elk CWD is transmittable to humans, research concerning CWD and its effect on the eco-system continues. Environmental and CWD problems in Estes Park, Colorado and, on a greater scale, throughout the Western U. S. and North America have local and federal policy makers searching for solutions. The Rocky Mountain National Park and the Estes Park environments are physically disrupted by the migration of the elk, ranging in size from calves to full-grown 700-pound adults. Several indigenous butterfly and plant species are harmed the aspen groves that the elk herd of 3,000 animals decimates in its search for food; the elk population, while taxing the common food resources adversely affects native species that share the same food supply, such as the indigenous beavers.
Fish and Wildlife Habitat Management Leaflet. 1999. American Elk: Cervus elaphus. United States Department of Agriculture. Habitat Management Institute. Tule elk Manitoban elk Roosevelt elk Chronic Wasting Disease Alliance Rocky Mountain Elk Foundation
American black bear
The American black bear is a medium-sized bear native to North America. It is the continent's smallest and most distributed bear species. American black bears are omnivores, with their diets varying depending on season and location, they live in forested areas, but do leave forests in search of food. Sometimes they become attracted to human communities because of the immediate availability of food; the American black bear is the world's most common bear species. It is listed by the International Union for Conservation of Nature as a least-concern species, due to its widespread distribution and a large population estimated to be twice that of all other bear species combined. Along with the brown bear, it is one of only two of the eight modern bear species not considered by the IUCN to be globally threatened with extinction. American black bears mark trees using their teeth and claws as a form of communication with other bears, a behavior common to many species of bears. Despite living in North America, American black bears are not related to brown bears and polar bears.
American and Asian black bears are considered sister taxa and are more related to each other than to the other modern species of bears. According to recent studies, the sun bear is a recent split from this lineage. A small primitive bear called Ursus abstrusus is the oldest known North American fossil member of the genus Ursus, dated to 4.95 mya. This suggests that U. abstrusus may be the direct ancestor of the American black bear, which evolved in North America. Although Wolverton and Lyman still consider U. vitabilis an "apparent precursor to modern black bears", it has been placed within U. americanus. The ancestors of American black bears and Asian black bears diverged from sun bears 4.58 mya. The American black bear split from the Asian black bear 4.08 mya. The earliest American black bear fossils, which were located in Port Kennedy, Pennsylvania resemble the Asian species, though specimens grew to sizes comparable to grizzly bears. From the Holocene to the present, American black bears seem to have shrunk in size, but this has been disputed because of problems with dating these fossil specimens.
The American black bear lived during the same period as the giant and lesser short-faced bears and the Florida spectacled bear. These tremarctine bears evolved from bears -- 8 ma; the giant and lesser short-faced bears are thought to have been carnivorous and the Florida spectacled bear more herbivorous, while the American black bears remained arboreal omnivores, like their Asian ancestors. The American black bear's generalist behavior allowed it to exploit a wider variety of foods and has been given as a reason why, of these three genera, it alone survived climate and vegetative changes through the last Ice Age while the other, more specialized North American predators became extinct. However, both Arctodus and Tremarctos had survived several previous ice ages. After these prehistoric ursids became extinct during the last glacial period 10,000 years ago, American black bears were the only bear present in much of North America until the migration of brown bears to the rest of the continent.
American black bears are reproductively compatible with several other bear species and have produced hybrid offspring. According to Jack Hanna's Monkeys on the Interstate, a bear captured in Sanford, was thought to have been the offspring of an escaped female Asian black bear and a male American black bear. In 1859, an American black bear and a Eurasian brown bear were bred together in the London Zoological Gardens, but the three cubs that were born died before they reached maturity. In The Variation of Animals and Plants under Domestication, Charles Darwin noted: In the nine-year Report it is stated that the bears had been seen in the zoological gardens to couple but to 1848 most had conceived. In the reports published since this date three species have produced young... An American black bear shot in autumn 1986 in Michigan was thought by some to be an American black bear/grizzly bear hybrid, due to its unusually large size and its proportionately larger braincase and skull. DNA testing was unable to determine whether it was a grizzly bear.
Listed alphabetically. American black bears occupied the majority of North America's forested regions. Today, they are limited to sparsely settled, forested areas. American black bears inhabit much of their original Canadian range, though they occur in the southern farmlands of Alberta and Manitoba; the total Canadian black bear population is between 396,000 and 476,000, based on surveys taken in the mid-1990s in seven Canadian provinces, though this estimate excludes American black bear populations in New Brunswick, the Northwest Territories, Nova Scotia and Saskatchewan. All provinces indicated stable populations of American black bears over the last decade; the current range of American black bears in the United States is constant throughout most of the northeast and within the Appalachian Mountains continuously from Maine to northern Georgia, the northern Midwest, the Rocky Mountain region, the West Coast and Alaska. However, it becomes fragmented or absent in other regions. Despite this, American black bears in those areas seem to have expanded their range during the last decade, such as with recent sightings in Ohio an
Sanders County, Montana
Sanders County is a county in the U. S. state of Montana. As of the 2010 United States Census, the population was 11,413, its county seat is Thompson Falls. The county was founded in 1905, it has an annual county fair with rodeo at Plains. According to the US Census Bureau, the county has a total area of 2,790 square miles, of which 2,761 square miles is land and 29 square miles is water. Sanders County lies on the state's western border, it is part of the Coeur d'Alene Mountains in the Bitterroot Range. The Clark Fork River flows southeast to northwest through the middle of the county,with the Bitterroot Mountains to the south and the Cabinet Mountains to the north, it is arid, with the west-facing mountain slopes capturing the most rain: ranging from nearly 40 inches a year in Heron on the Western end of the county to less than 12 inches per year in Dixon on the East end. During the last ice age, this was the area; when the ice dam broke, the resulting floods created the Scablands in eastern Washington.
A variety of birds and other wildlife are found in Sanders County. The Tufted duck has been observed along the Bull River. An amphibian, the Rough-skinned Newt, has a disjunctive population at Thompson Falls, un-contiguous with the remainder of the Western United States population of this species. Sanders County is a "destination hunting locale" with trophy specimens of White-tailed Deer, Mule Deer, Rocky Mountain Elk, Shiras Moose, Mountain Goat, Bighorn Sheep rounding out huntable ungulate species and Black Bear and Wolves comprising the huntable carnivores. Rocky Mountain Bighorns are hunted in the county. Grizzly bear, the Montana state animal, are found in the county, but as an endangered species, hunting them is prohibited. Montana had the last huntable population of Grizzlies in the lower 48, allowing 10 bears a year as late as the 1990s. Only Alaska allows hunting for Grizzlies at present. Western Meadowlark, the state bird are found sparsely in the meadow areas of Sanders County along with Redwing Blackbird and Rocky Mountain Bluebirds.
The westslope cutthroat trout is native to the drainages of Sanders County. The threatened native bull trout relies on westslopes as a major prey species in its piscivorous diet. Catch and release fishing is required to maintain fishable populations of the two natives, which now compete with introduced rainbow trout, warm-water species, such as largemouth bass, yellow perch, Northern Pike, walleyes that have been introduced and thrive in the modified habitat of the Clark Fork River's reservoirs. Sanders County is part of the mountainous western third of Montana, it lies on the western slopes of the Rocky Mountains with a mixed coniferous forest dominating the plant community. Douglas fir/Ponderosa pine climax plant community dominate much of the county, but there are numerous other conifers found there as well in pockets of micro-climates suited to their needs; these include Western red cedar, Western Hemlock, Mountain Hemlock, White Spruce, Subalpine Fir, Grand Fir, Western White Pine, Lodgepole Pine and one of the most spectacular, Western larch, one of a handful of deciduous conifers that turn gold in the autumn before dropping their needles.
Numerous broadleaf species proliferate in Sanders County: Rocky Mountain Maple, Red Alder, Paperbark Birch, Chokecherry and poplar. Arguably the most popular broad-leaf shrub in Sanders County is the Rocky Mountain huckleberry. Trout Creek, Montana 59874 is considered the "Huckleberry Capital of Montana" and holds an annual huckleberry celebration in August. Though related to the common blueberry few have managed to grow Rocky Mountain huckleberry in domestic cultivation, it is found in plant communities with beargrass, a perennial found in burned or logged-over areas of the county's mountains. The bitterroot, the state flower, is found in limited quantities in Sanders County; as of the 2000 United States Census there were 10,227 people, 4,273 households, 2,897 families in the county. The population density was four people per square mile. There were 5,271 housing units at an average density of two per square mile; the racial makeup of the county was 91.91% White, 0.13% Black or African American, 4.74% Native American, 0.30% Asian, 0.01% Pacific Islander, 0.26% from other races, 2.64% from two or more races.
1.55% of the population were Hispanic or Latino of any race. 20.1% were of German, 12.1% English, 11.0% Irish, 7.9% American and 6.5% Norwegian ancestry. 96.9% spoke English, 1.4% German and 1.2% Spanish as their first language. There were 4,273 households out of which 26.20% had children under the age of 18 living with them, 57.30% were married couples living together, 7.10% had a female householder with no husband present, 32.20% were non-families. 28.00% of all households were made up of individuals and 11.60% had someone living alone, 65 years of age or older. The average household size was 2.35 and the average family size was 2.86. The county population contained 23.80% under the age of 18, 5.50% from 18 to 24, 22.10% from 25 to 44, 31.80% from 45 to 64, 16.90% who were 65 years of age or older. The median age was 44 years. For every 100 females there were 102.10 males. For every 100 females age 18 and over, there were 100.50
American Bison Society
The American Bison Society was founded in 1905 by pioneering conservationists and sportsmen including William T. Hornaday and Theodore Roosevelt to help save the bison from extinction and raise public awareness about the species. Over 40 million American bison once roamed the plains and grasslands from Mexico to central Canada, shaping the landscape with their migrations, grazing patterns, behavior. By the 1870s, their populations had been decimated by westward over-hunting. An 1889 survey published by Hornaday, who would go on to become the first director of the Bronx Zoo, showed that 1,000 bison remained in North America; the American Bison Society was formed to prevent the extinction of the American bison. In 1907, the ABS shipped 15 bison from the Bronx Zoo to the Wichita Mountains Wildlife Refuge and Game Preserve in Oklahoma by cart and rail; this was the first animal reintroduction in North America. In 1908, following successful petitioning by ABS, the US Congress passed a bill to establish a permanent National Bison Range in Montana, provided that ABS raise the $10,000 needed to purchase the animals for the herd.
They exceeded this fundraising goal, in 1909, these animals were released on the new national range. In 1913, the New York Zoological Society, working with ABS, donated 14 bison to Wind Cave National Park in South Dakota, ABS assisted in founding the herd at Fort Niobrara National Wildlife Refuge in Nebraska; because of the secure populations of bison in these public herds, the ABS considered their work done, the organization was disbanded in 1935. In 2005, the American Bison Society was re-launched by the Wildlife Conservation Society to secure the ecological future of bison in North America. On August 12, 2010 National Geographic published a progress report on the Wood Bison Recovery Program supported in part by WCS- North America. American Bison Society WCS Institute’s ABS Web pages Wildlife Conservation Society website American Bison Society collection finding aid, Wildlife Conservation Society Archives
American Indian Wars
The American Indian Wars is the collective name for the various armed conflicts fought by European governments and colonists, the United States and Canadian governments and American and Canadian settlers, against various American Indian and First Nation tribes. These conflicts occurred in North America from the time of the earliest colonial settlements in the 17th century until the 1920s; the various Indian Wars resulted from a wide variety of factors, including cultural clashes, land disputes, criminal acts committed on both sides. European powers and the colonies enlisted Indian tribes to help them conduct warfare against one another's colonial settlements. After the American Revolution, many conflicts were local to specific states or regions and involved disputes over land use; the British Royal Proclamation of 1763, included in the Constitution of Canada, prohibited white settlers from taking the lands of indigenous peoples in Canada without signing a treaty with them. It continues to be the law in Canada today, 11 Numbered Treaties, covering most of the First Nations lands, limited the number of such conflicts.
As white settlers spread westward across America after 1780, the size and intensity of armed conflicts increased between settlers and various cultures of Indians. The climax came in the War of 1812, which resulted in the defeat of major Indian coalitions in the Midwest and the South. Conflict with settlers became much less common and were resolved by treaty through sale or exchange of territory between the federal government and specific tribes; the Indian Removal Act of 1830 authorized the US government to enforce the Indian removal from east of the Mississippi River to the west, what the government considered the sparsely populated American frontier. The federal US policy of removal was refined in the West, as American settlers kept expanding their territories, to relocate Indian tribes to specially designated and federally protected reservations; the colonization of North America by the English, Spanish and Swedish was resisted by some Indian tribes and assisted by other tribes. Wars and other armed conflicts in the 17th and 18th centuries included: Beaver Wars between the Iroquois and the French, who allied with the Algonquians Anglo-Powhatan Wars, including the 1622 Jamestown Massacre, between English colonists and the Powhatan Confederacy in the Colony of Virginia Pequot War of 1636–38 between the Pequot tribe and colonists from the Massachusetts Bay Colony and Connecticut Colony Kieft's War in the Dutch territory of New Netherland between colonists and the Lenape people Peach Tree War, the large-scale attack by the Susquehannocks and allied tribes on several New Netherland settlements along the Hudson River Esopus Wars, conflicts between the Esopus tribe of Lenape Indians and colonial New Netherlanders in Ulster County, New York King Philip's War in New England between colonists and the Narragansett people Tuscarora War in the Province of North Carolina Yamasee War in the Province of South Carolina Dummer's War in northern New England and French Acadia Pontiac's War in the Great Lakes region Lord Dunmore's War in western Virginia In several instances, warfare in America was a reflection of European rivalries, with American Indian tribes splitting their alliances among the powers siding with their trading partners.
Various tribes fought on each side in King William's War, Queen Anne's War, Dummer's War, King George's War, the French and Indian War, allying with British or French colonists according to their own self interests. Indian tribes differed in their alliances during the American Revolution and the War of 1812; the Cherokees supported the British in the Revolutionary War and raided frontier American settlements in the hope of driving out the settlers, four Iroquois tribes fought against the Patriots. Other tribes fought for the American Patriots, such as the Oneida people and Tuscarora people of the Iroquois Confederacy in New York. British merchants and government agents began supplying weapons to Indians living in the United States following the Revolution in the hope that, if a war broke out, they would fight on the British side; the British further planned to set up an Indian nation in the Ohio-Wisconsin area to block further American expansion. The US protested and went to war in 1812. Most Indian tribes supported the British those allied with Tecumseh, but they were defeated by General William Henry Harrison.
The War of 1812 spread to Indian rivalries, as well. Many refugees from defeated tribes went over the border to Canada. During the early 19th century, the federal government was under pressure by settlers in many regions to expel Indians from their areas; the Indian Removal Act of 1830 offered Indians the choices of assimilating and giving up tribal membership, relocation to an Indian reservation with an exchange or payment for lands, or moving west. Some resisted most notably the Seminoles in a series of wars in Florida, they were never defeated. The United States gave up on the remainder, by living defensively deep in the swamps and Everglades. Others were moved to reservations west of the Mississippi River, most famously the Cherokee whose relocation was call
Columbian ground squirrel
The Columbian ground squirrel, is a species of rodent common in certain regions of Canada and the northwestern United States. It is the second largest member of the genus Urocitellus, part of the tribe Marmotini, along with marmots, prairie dogs, other holarctic ground squirrels, they are stout, with short dense fur, characteristically tawny across the bridge of the nose. Social encounters are initiated with kissing behavior and the most common activity above ground is standing at attention. Residing in mountainous terrain and high plains in northern latitudes, they hibernate most of the year in underground burrows, which may be used for many years, they are emaciated. These long periods of torpor earned the squirrels the moniker "Seven Sleepers", since the rests last around seven months; the Columbian ground squirrel came to the attention of the scientific community through writings produced by Lewis and Clark, while 21st century molecular genetics has more finely illuminated its ties with other close relatives.
The Columbian ground squirrel is one of the largest members of the genus, the largest being the Arctic ground squirrel. They have a sturdy, robust build, they measure 325–410 mm in length overall, with a tail measuring 80–116 mm. The hind feet measure 47–57 mm and the ear 16–22.5 mm. The hair is dense and short; the facial fur is bronze across the bridge of the nose. The fur along the back and feet is a more cinnamon buff, with darker fur closer to the body. There is a pale beige to buff ring of fur around the eye; the neck fur is gray along the sides of the cheeks. The flanks may be light gray, they have a darker tail, with darker underfur and some lighter beige markings above and dark to grayish white below. Molting occurs diffusely, without a clear line of delineation. Two subspecies have been described. Compared with U. c. columbianus, the population U. c. ruficaudus has a tail more rufous and less gray above. The sides of the face and throat are more rust shaded; the legs and feet are darker as well.
The skull of U. c. ruficaudus is broader, with more robust zygomatic arches. Several albino variants have been found. An albino squirrel was captured alive by a student near Pullman, Washington in 1932, it had been in an alfalfa field. The animal had pink eyes. A zoologist reported intentions to keep the animal alive to study genetic inheritance patterns; the following year, he reported finding three more young albinos in the same area. Around 30 years prior, two albino skins had been collected near Pullman, it was proposed. The Columbia ground squirrel is found in western areas of North America, it occurs in the Rocky Mountains, from as far north as western Alberta and southeastern British Columbia. They are found in the western parts of Montana, through central Idaho and into northern and eastern reaches of Washington, they are found along plains of eastern Washington. In Oregon, they occur in mountainous area in the east-central part of the state, they reside between 700–8,000 feet in elevation. The known fossil record of the Columbia ground squirrel consists of specimens recovered from the Wasden fossil site in Bonneville County, Idaho.
Fossils from this site date to the late Pleistocene. The site is located at 1,584 metres elevation. Fossils of small mammals deposited at this site are attributed to owl predation; the distribution of the Columbia ground squirrel in Oregon was assessed based on consideration of animals obtained in 71 localities. Over 98% were obtained in the Blue Mountains ecoregion, which includes the Wallowa and Blue Mountain ranges; the remaining squirrels came from the Owyheee Uplands. Columbian ground squirrels in Alberta hibernate around 250 days a year, with only 69–94 days of activity observed; the amount of time active varies depending on local climate as well as variations in behavior of animals of different sexes and ages. During hibernation, the squirrels are positioned vertically in a tight ball; the temperature drops the heart rate slows and respirations are scarcely perceptible. The first group to emerge are the adult males, followed by adult females, yearlings juveniles. Animals at higher elevations and latitudes emerge later.
They emerge from start breeding earlier at low elevations. One brood per year will be raised. Young are born naked and toothless. After 5–6 days, their weight has doubled, they are covered with dark silky hair by day 12. Around day 17, the eyes are beginning to open, they may emerge into the sunlight outside the den around day 21-24. After 4 weeks, they are able to leave the nest altogether. Mammalogist Vernon Orlando Bailey examined a Columbia ground squirrel burrow at an elevation of 7,000 ft near the Piegan Pass in Glacier National Park. In late July, a stout adult female was found bringing up fresh soil to the burrow entrance daily; the animal was removed and the burrow excavated for examination The mound at the entrance consisted of an estimated 8 US gal of soil. The soil was of varying dates of accumulation, since the lower layers appeared packed from previous seasons; the burrow itself had this main opening as well as two alternates, which were concealed from external observation and served as avenues of escape if a predator were to enter the burrow.
The main shafts of the burrow were around 3.5 in in diameter. Chambers were established and varying intervals throughout the burrow to allow for storage of earth be