Pryor Mountain Mustang
Encyclopedia
The Pryor Mountain Mustang is a substrain of Mustang
considered to be genetically unique and one of the few strains of horses verified by DNA
analysis to be descended from the original Colonial Spanish Horses brought to the Americas by the Spanish. They live on the Pryor Mountains Wild Horse Range
located in the Pryor Mountains
of Montana
and Wyoming
in the United States
. They are protected by the Wild and Free-Roaming Horses and Burros Act of 1971
and managed by the Bureau of Land Management
(BLM). Because of the unique genetic makeup of the Pryor Mountains Mustang herd, equine geneticist Dr. E. Gus Cothran concluded in 1992 that "the Pryor herd may be the most significant wild-horse herd remaining in the United States." Dr. D. Phillip Sponenberg, equine veterinarian
at Virginia-Maryland Regional College of Veterinary Medicine
, agreed, noting, "[These animals] don't exist anywhere else." This herd was the subject of the 1995 documentary film Cloud: Wild Stallion of the Rockies and its sequel, the 2003 documentary film Cloud's Legacy: The Wild Stallion Returns.
. The animal is generally high, with an average of 14 to 14.2 hands. The horses weigh 700 lbs on the range, and more if raised in captivity. The animals exhibit a wide range of solid colors, including bay, black
, chestnut
, dun
, grullo
, and blue or red roan
. Buckskin coloring is rare but does occur, and pinto
coloring can be minimally expressed. However, the majority of colors are dun or grullo. Nearly all the horses on the range exhibit primitive markings
such as dorsal stripes, transverse stripes across the withers
, and horizontal "zebra" stripes on the back of the forelegs. The Pryor Mountains horse's body is heavy, with strong bones. Manes and tails tend to be long, and the horse's winter coat is very heavy and often curly. The head is convex or straight (the "Roman nose" identified by horse breeders), with wide-set eyes, hooked ears, and a broad forehead that tapers to well to the muzzle. The front teeth meet evenly, the upper lip is usually longer than the lower, and the nostrils are small and crescent shaped. The neck is medium in length, and most of the animals have only five lumbar vertebrae (an anatomical feature common in primitive horses)—although some have a fifth and sixth vertebrae which are fused. The horse's shoulders are long and sloping, the withers
are prominent, and chests are medium to narrow in width. The croup
is generally sloped, and tail-set is low. The hooves are ample and very hard.
Pryor Mountains Mustangs exhibit a natural Ambling
gait. The horses are generally intelligent, strong, and sure-footed, and exhibit great stamina. Like all feral horses, they generally avoid human contact, are distrustful, and are easily spooked. However, once they are familiar with an individual, they can exhibit a strong social bond with that individual. Pryor Mountains horses can be broken and ridden, and trained to do any task a domesticated horse can perform. Trained Pryor Mountains horses have a calm temperament, and are alert on trails.
The horses form bands or "harems," in which a single stallion mates and controls a group of about six mares. Another eight to 10 "bachelor" stallions accompany the band at a distance, hoping to win control of it from the stallion or mate with mares.
maintains that the horses were brought to the area by about 1725. Non-Indian explorers found native people in possession of large numbers of horses as early as 1743. Thousands of feral horses lived in the area by the time American pioneers began settling near the Pryor Mountains in the late 1800s.
It was widely believed that the Pryor Mountains horses were direct descendants of the Barb
horses brought to North America by Juan de Oñate
's expedition to explore America north of the Rio Grande
in the early 1600s. Their bloodlines may also include American Saddlebred
, Canadian
, Irish Hobby
, and Tennessee Walking horses. But this was in dispute for many years. Some people claimed that the horses were nothing more than local domestic horses which had escaped to the wild. In 1992, equine geneticist Dr. E. Gus Cothran ran genetic studies on the herd, and concluded that their primary bloodline descends from Spanish Barbs. Since no genetic variants were observed which were not also seen in domestic horse breeds, in 2010 Cothran concluded the horses were not a unique species which had survived from prehistoric times. Rather, they were linear descendants of the Spanish Barb, with some evidence of genetic similarity to light racing and riding breeds. The genetic tests also revealed that the Pryor Mountains horses carried a rare allele
variant known as "Qac" that only Spanish horses
brought to the Americas also carried. Dr. D. Phillip Sponenberg of the Virginia–Maryland Regional College of Veterinary Medicine, and an expert on horse breeds, observed that, physically, the horses conform to the Colonial Spanish Horse type. Genetic studies have also revealed that the herd exhibits a high degree of genetic diversity, and BLM has acknowledged the genetic uniqueness of the herd.
Management of the Pryor Mountains horse herd has focused on fulfilling the Free-Roaming Wild Horse and Burro Act's requirement that BLM maintain a "thriving natural ecological balance". In general, BLM initially focused on how many horses the range could support and in maintaining conformity to the Pryor Mountains standard. However, with the development of DNA
testing in the mid 1980s, the focus changed to maintaining the herd's genetic viability as well. In 1988, researchers at Washington State University
authored a paper which raised concern that the herd exhibited a lack of genetic diversity, and could be suffering from genetic drift
and/or a population bottleneck
. BLM contracted with veterinarian E. Gus Cothran (then at the College of Veterinary Medicine at the University of Kentucky, but now at the Texas A&M College of Veterinary Medicine & Biomedical Sciences
) to take random genetic samples of the herd in 1994, 1997, and 2001. Cothran's analysis found "no evidence of a bottleneck". Genetic diversity was actually above the mean for feral horse herds in the United States, and just below the mean for domesticated breeds. The BLM, however, interpreted these studies in 2009 to indicate that the genetic diversity of the Pryor Mountains herd is "well above" the mean for domestic breeds. Cothran considered the herd to be in genetic equilibrium, although he cautioned that a minimum of 120 breeding-age animals should be kept on the range to maintain the genetic health of the herd. Research by biologists and veterinarians at Colorado State University
, the University of Kentucky
, and other colleges found that there is little inbreeding
in bands, as the stallions tend to drive off colts
when they are about two years old.
For years, BLM had also allowed any horse to be adopted from the range. Since adopters favored "pretty" horses, the color genetics of the herd altered so that mostly bays and blacks were left on the range. Adoption procedures changed in 1994 so that now the original colors and patterns of the herd are returning. That same year, a private group calling itself the Pryor Mountains Mustang Breeders Association was formed to preserve the gene pool of the herd and establish a registry for Pryor Mountains horses in private hands. In order to be placed on the register, the horse must have a registered sire and dam, have a title issued either by BLM or the Tillett ranch, and have a certificate of blood typing from the Gluck Equine Research Center at the University of Kentucky. As of 2008, 209 horses in 16 U.S. states and one Canadian province were on the registry.
BLM undertook a roundup of the horse herd in 1997 to reduce its numbers, and The BLM officials expected to do another in late 2000 when the herd size reached 200. By August 1999, there were 180 adult horses and colts on the range. In May 2009, after several long-term studies of the rangeland, The BLM determined that the range's maximum carrying capacity was 179 feral horses. This assumed that all BLM land, as well as lands leased from other owners (public and private), would continue to be available to the animals, and that BLM would be able to manage the horses by using artificial watering sites to encourage the horses to utilize undergrazed portions of the range. The BLM also said it would implement other range management techniques The BLM also proposed purchasing 1467 acres (593.7 ha) of land from the state of Montana, and another 632 acres (255.8 ha) of private land, to add to the range.
At the same time, BLM said it would reduce the herd from its existing 195 adults to 120. The stated goal was to temporarily remove horses from the refuge to allow the range to recover from the historic overgrazing caused by livestock, not because BLM believed there were too many horses on the range. Sixty percent of the remaining horses would be males, to reduce the rate of population growth. The agency said it would remove 30 horses a year from the herd and stable them at a yearly cost of $18,000 to $21,000 until the correct herd size and sex ratios had been reached. Horses to be removed from the herd included those which did not closely fit the conformity type; which were genetically well-represented; which were 11 to 15 years of age, had sired or foaled, and were not band stallions; and were between five and 10 years of age or 16 to 20 years of age. Genetic diversity would be measured by visual observation of the herd's conformity to type using a visual system developed by Dr. Sponenberg, and measures taken to improve genetic diversity if signs of inbreeding occurred. The Cloud Foundation and Front Range Equine Rescue, both feral horse advocacy groups, challenged the roundup in federal court. A federal district court judge delayed the roundup three days to consider their request, but on September 2, 2009, rejected the injunction and allowed the roundup to proceed. BLM began its roundup of feral horses on the Pryor Mountains range in early September 2009. After several days, 130 of 188 feral horses were rounded up. Forty-six horses were put up for adoption, while the freed mares were given a contraceptive vaccine to help keep the herd population down.
At this time, BLM also placed "guzzlers" on the range. A guzzler is a precipitation (usually rainwater) collection device which traps water in a storage tank ranging in size from a few to several thousand gallons. The storage tank can be above-ground, partially buried, or below-ground. A mechanical valve releases water into a drinking trough from the storage tanks, allowing animals access to the water. When the valve senses that the water level in the trough is low, it opens and allows more water into the drinking area. Five guzzlers were placed in undergrazed areas to encourage the horses to better utilize this forage.
In the fall of 2010, BLM issued a set of draft strategy documents for operating its wild horse programs, and solicited public comment on the plans. After receiving numerous comments, BLM said in February 2011 it would quicken the pace at which it made revisions to its roundup procedures, use of fertility control drugs, and wild horse and burro range land management. The agency also commissioned a study from the National Academies of Science (NAS) on wild-horse management. Due for release in 2013, independent NAS experts will study a wide variety of issues, including the carrying capacity of wild horse and burro ranges, wild horse and burro population growth, and best practices in fertility control.
In September 2011, BLM announced it would begin working with the Humane Society of the United States
to develop new practices in herd management and roundup, and increase its emphasis on adoptions and the use of drugs as fertility control to help better manage its wild horse herds.
, by traveling south on U.S. Route 310
and then taking the Forest Service gravel road to Dryhead Overlook. Some of the range may be accessed via the Crow Indian Reservation
. A trespass permit from the Crow Nation is required to cross tribal land or exit a vehicle while on tribal land. Hiking on the Pryor Mountains Wild Horse range is good, but there are no maintained or marked trails and (as of 2000) no guidebooks to the area.
Mustang (horse)
A Mustang is a free-roaming horse of the North American west that first descended from horses brought to the Americas by the Spanish. Mustangs are often referred to as wild horses, but there is intense debate over terminology...
considered to be genetically unique and one of the few strains of horses verified by DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
analysis to be descended from the original Colonial Spanish Horses brought to the Americas by the Spanish. They live on the Pryor Mountains Wild Horse Range
Pryor Mountains Wild Horse Range
The Pryor Mountains Wild Horse Range is a refuge for a historically signifcant herd of free-roaming Mustangs, feral horses colloquially called "wild horses", located in the Pryor Mountains of Montana and Wyoming in the United States. The range has an area of and was established in 1968 along the...
located in the Pryor Mountains
Pryor Mountains
The Pryor Mountains are a mountain range in Carbon County, Montana and Big Horn County, Montana. They are located on the Crow Indian Reservation and the Custer National Forest, and portions of them are on private land...
of Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
and Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. They are protected by the Wild and Free-Roaming Horses and Burros Act of 1971
Wild and Free-Roaming Horses and Burros Act of 1971
The Wild and Free-Roaming Horses and Burros Act of 1971 , is an Act of Congress , signed into law President Richard M. Nixon on December 18, 1971...
and managed by the Bureau of Land Management
Bureau of Land Management
The Bureau of Land Management is an agency within the United States Department of the Interior which administers America's public lands, totaling approximately , or one-eighth of the landmass of the country. The BLM also manages of subsurface mineral estate underlying federal, state and private...
(BLM). Because of the unique genetic makeup of the Pryor Mountains Mustang herd, equine geneticist Dr. E. Gus Cothran concluded in 1992 that "the Pryor herd may be the most significant wild-horse herd remaining in the United States." Dr. D. Phillip Sponenberg, equine veterinarian
Veterinarian
A veterinary physician, colloquially called a vet, shortened from veterinarian or veterinary surgeon , is a professional who treats disease, disorder and injury in animals....
at Virginia-Maryland Regional College of Veterinary Medicine
Virginia-Maryland Regional College of Veterinary Medicine
The Virginia-Maryland Regional College of Veterinary Medicine is a state-supported college of two states, Virginia and Maryland, filling the need for veterinary medicine education in both states. Students from both states are considered "in-state" students for admissions purposes.VMRCVM is one of...
, agreed, noting, "[These animals] don't exist anywhere else." This herd was the subject of the 1995 documentary film Cloud: Wild Stallion of the Rockies and its sequel, the 2003 documentary film Cloud's Legacy: The Wild Stallion Returns.
Characteristics
The Pryor Mountain Mustang has a very specific conformation typeEquine conformation
Equine conformation evaluates the degree of correctness of a horse's bone structure, musculature, and its body proportions in relation to each other. Undesirable conformation can limit the ability to perform a specific task. Although there are several universal "faults," a horse's conformation is...
. The animal is generally high, with an average of 14 to 14.2 hands. The horses weigh 700 lbs on the range, and more if raised in captivity. The animals exhibit a wide range of solid colors, including bay, black
Black (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
, chestnut
Chestnut (coat)
Chestnut is a hair coat color of horses consisting of a reddish-to-brown coat with a mane and tail the same or lighter in color than the coat. Genetically and visually, chestnut is characterized by the absolute absence of true black hairs...
, dun
Dun gene
The dun gene is a dilution gene that affects both red and black pigments in the coat color of a horse. The dun gene has the ability to affect the appearance of all black, bay, or chestnut -based horses to some degree by lightening the base body coat and suppressing the underlying base color to the...
, grullo
Grullo
Grullo is a color of horses in the dun family, characterized by tan-gray or mouse-colored hairs on the body, often with shoulder and dorsal stripes and black barring on the lower legs. In this coloration each individual hair is mouse-colored, unlike a roan which is composed of a mixture of dark and...
, and blue or red roan
Roan (horse)
Roan is a horse coat color pattern characterized by an even mixture of colored and white hairs on the body, while the head and "points"—lower legs, mane and tail—are more solid-colored. The roan pattern is dominantly-inherited, and is found in many horse breeds...
. Buckskin coloring is rare but does occur, and pinto
Pinto horse
A pinto horse has a coat color that consists of large patches of white and any other color. The distinction between "pinto" and "solid" can be tenuous, as so-called "solid" horses frequently have areas of white hair. Various cultures throughout history appear to have selectively bred for pinto...
coloring can be minimally expressed. However, the majority of colors are dun or grullo. Nearly all the horses on the range exhibit primitive markings
Primitive markings
Primitive markings among domestic horses are a group of hair coat markings and qualities associated with primitive breeds, and the dun coat color family in particular. All dun horses possess at least the dorsal stripe but the presence of the other primitive markings varies...
such as dorsal stripes, transverse stripes across the withers
Withers
The withers is the ridge between the shoulder blades of a four-legged animal. In many species it is the tallest point of the body, and in horses and dogs it is the standard place to measure the animal's height .-Horses:The withers in horses are formed by the dorsal spinal processes of roughly the...
, and horizontal "zebra" stripes on the back of the forelegs. The Pryor Mountains horse's body is heavy, with strong bones. Manes and tails tend to be long, and the horse's winter coat is very heavy and often curly. The head is convex or straight (the "Roman nose" identified by horse breeders), with wide-set eyes, hooked ears, and a broad forehead that tapers to well to the muzzle. The front teeth meet evenly, the upper lip is usually longer than the lower, and the nostrils are small and crescent shaped. The neck is medium in length, and most of the animals have only five lumbar vertebrae (an anatomical feature common in primitive horses)—although some have a fifth and sixth vertebrae which are fused. The horse's shoulders are long and sloping, the withers
Withers
The withers is the ridge between the shoulder blades of a four-legged animal. In many species it is the tallest point of the body, and in horses and dogs it is the standard place to measure the animal's height .-Horses:The withers in horses are formed by the dorsal spinal processes of roughly the...
are prominent, and chests are medium to narrow in width. The croup
Rump (animal)
The rump or croup, in the external morphology of an animal, is the portion of the posterior dorsum that is posterior to the loins and anterior to the tail. Anatomically, the rump corresponds to the sacrum....
is generally sloped, and tail-set is low. The hooves are ample and very hard.
Pryor Mountains Mustangs exhibit a natural Ambling
Ambling
The term amble or ambling is used to describe a number of four-beat intermediate gaits of horses. All are faster than a walk but usually slower than a canter or gallop...
gait. The horses are generally intelligent, strong, and sure-footed, and exhibit great stamina. Like all feral horses, they generally avoid human contact, are distrustful, and are easily spooked. However, once they are familiar with an individual, they can exhibit a strong social bond with that individual. Pryor Mountains horses can be broken and ridden, and trained to do any task a domesticated horse can perform. Trained Pryor Mountains horses have a calm temperament, and are alert on trails.
The horses form bands or "harems," in which a single stallion mates and controls a group of about six mares. Another eight to 10 "bachelor" stallions accompany the band at a distance, hoping to win control of it from the stallion or mate with mares.
History
Historians and scientists speculate that feral horses have lived on and near Pryor Mountains since at least the late 1600s. Crow Indian traditionCrow Nation
The Crow, also called the Absaroka or Apsáalooke, are a Siouan people of Native Americans who historically lived in the Yellowstone River valley, which extends from present-day Wyoming, through Montana and into North Dakota. They now live on a reservation south of Billings, Montana and in several...
maintains that the horses were brought to the area by about 1725. Non-Indian explorers found native people in possession of large numbers of horses as early as 1743. Thousands of feral horses lived in the area by the time American pioneers began settling near the Pryor Mountains in the late 1800s.
It was widely believed that the Pryor Mountains horses were direct descendants of the Barb
Barb (horse)
Developed on the Barbary Coast of North Africa, the Barb horse is a desert breed with great hardiness and stamina. The Barb generally possesses a fiery temperament and an atypical sport-horse conformation, but nevertheless has influenced modern breeds....
horses brought to North America by Juan de Oñate
Juan de Oñate
Don Juan de Oñate y Salazar was a Spanish explorer, colonial governor of the New Spain province of New Mexico, and founder of various settlements in the present day Southwest of the United States.-Biography:...
's expedition to explore America north of the Rio Grande
Rio Grande
The Rio Grande is a river that flows from southwestern Colorado in the United States to the Gulf of Mexico. Along the way it forms part of the Mexico – United States border. Its length varies as its course changes...
in the early 1600s. Their bloodlines may also include American Saddlebred
American Saddlebred
The American Saddlebred, formerly known as the American Saddle Horse, is a breed of horse that was developed in Kentucky by plantation owners. Today, in the horse show world, they are most commonly seen under saddle in Saddle seat style riding, and in various types of driving, including pleasure...
, Canadian
Canadian Horse
The Canadian Horse is a breed of horse developed in Canada. Although previously relatively unknown due to its rarity, the Canadian Horse has influenced many other North American breeds, including the Morgan, American Saddlebred, and Standardbred...
, Irish Hobby
Irish Hobby
The Irish Hobby is an extinct breed of horse native to the British Isles that developed prior to the 13th Century. The breed provided foundation bloodlines for several modern horse breeds, including breeds as diverse as the Connemara pony and the Irish Draught....
, and Tennessee Walking horses. But this was in dispute for many years. Some people claimed that the horses were nothing more than local domestic horses which had escaped to the wild. In 1992, equine geneticist Dr. E. Gus Cothran ran genetic studies on the herd, and concluded that their primary bloodline descends from Spanish Barbs. Since no genetic variants were observed which were not also seen in domestic horse breeds, in 2010 Cothran concluded the horses were not a unique species which had survived from prehistoric times. Rather, they were linear descendants of the Spanish Barb, with some evidence of genetic similarity to light racing and riding breeds. The genetic tests also revealed that the Pryor Mountains horses carried a rare allele
Allele
An allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...
variant known as "Qac" that only Spanish horses
Iberian horse
The Iberian horse is a title given to a number of horse breeds native to the Iberian peninsula. At present, 17 horse breeds are recognized by FAO as characteristic of the Iberian Peninsula....
brought to the Americas also carried. Dr. D. Phillip Sponenberg of the Virginia–Maryland Regional College of Veterinary Medicine, and an expert on horse breeds, observed that, physically, the horses conform to the Colonial Spanish Horse type. Genetic studies have also revealed that the herd exhibits a high degree of genetic diversity, and BLM has acknowledged the genetic uniqueness of the herd.
Management
BLM counts the herd visually about every four years by flying over the range, reporting on each animal found, and using statistical methods to correct for historic undercounting and other problems. In 1984, BLM set the maximum carrying capacity of the Pryor Mountains Wild Horse Range at 121 adult animals, and revised this to 95 adult animals in 1992.Management of the Pryor Mountains horse herd has focused on fulfilling the Free-Roaming Wild Horse and Burro Act's requirement that BLM maintain a "thriving natural ecological balance". In general, BLM initially focused on how many horses the range could support and in maintaining conformity to the Pryor Mountains standard. However, with the development of DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
testing in the mid 1980s, the focus changed to maintaining the herd's genetic viability as well. In 1988, researchers at Washington State University
Washington State University
Washington State University is a public research university based in Pullman, Washington, in the Palouse region of the Pacific Northwest. Founded in 1890, WSU is the state's original and largest land-grant university...
authored a paper which raised concern that the herd exhibited a lack of genetic diversity, and could be suffering from genetic drift
Genetic drift
Genetic drift or allelic drift is the change in the frequency of a gene variant in a population due to random sampling.The alleles in the offspring are a sample of those in the parents, and chance has a role in determining whether a given individual survives and reproduces...
and/or a population bottleneck
Population bottleneck
A population bottleneck is an evolutionary event in which a significant percentage of a population or species is killed or otherwise prevented from reproducing....
. BLM contracted with veterinarian E. Gus Cothran (then at the College of Veterinary Medicine at the University of Kentucky, but now at the Texas A&M College of Veterinary Medicine & Biomedical Sciences
Texas A&M College of Veterinary Medicine & Biomedical Sciences
The Texas A&M College of Veterinary Medicine & Biomedical Sciences is a college of Texas A&M University in College Station, Texas.Founded in 1916, the Texas A&M College of Veterinary Medicine & Biomedical Sciences is one of only 31 colleges of veterinary medicine in the United States and Canada. It...
) to take random genetic samples of the herd in 1994, 1997, and 2001. Cothran's analysis found "no evidence of a bottleneck". Genetic diversity was actually above the mean for feral horse herds in the United States, and just below the mean for domesticated breeds. The BLM, however, interpreted these studies in 2009 to indicate that the genetic diversity of the Pryor Mountains herd is "well above" the mean for domestic breeds. Cothran considered the herd to be in genetic equilibrium, although he cautioned that a minimum of 120 breeding-age animals should be kept on the range to maintain the genetic health of the herd. Research by biologists and veterinarians at Colorado State University
Colorado State University
Colorado State University is a public research university located in Fort Collins, Colorado. The university is the state's land grant university, and the flagship university of the Colorado State University System.The enrollment is approximately 29,932 students, including resident and...
, the University of Kentucky
University of Kentucky
The University of Kentucky, also known as UK, is a public co-educational university and is one of the state's two land-grant universities, located in Lexington, Kentucky...
, and other colleges found that there is little inbreeding
Inbreeding
Inbreeding is the reproduction from the mating of two genetically related parents. Inbreeding results in increased homozygosity, which can increase the chances of offspring being affected by recessive or deleterious traits. This generally leads to a decreased fitness of a population, which is...
in bands, as the stallions tend to drive off colts
Colt (horse)
A colt is a young male horse, under the age of four. The term "colt" is often confused with foal, which refers to a horse of either sex under one year of age....
when they are about two years old.
For years, BLM had also allowed any horse to be adopted from the range. Since adopters favored "pretty" horses, the color genetics of the herd altered so that mostly bays and blacks were left on the range. Adoption procedures changed in 1994 so that now the original colors and patterns of the herd are returning. That same year, a private group calling itself the Pryor Mountains Mustang Breeders Association was formed to preserve the gene pool of the herd and establish a registry for Pryor Mountains horses in private hands. In order to be placed on the register, the horse must have a registered sire and dam, have a title issued either by BLM or the Tillett ranch, and have a certificate of blood typing from the Gluck Equine Research Center at the University of Kentucky. As of 2008, 209 horses in 16 U.S. states and one Canadian province were on the registry.
BLM undertook a roundup of the horse herd in 1997 to reduce its numbers, and The BLM officials expected to do another in late 2000 when the herd size reached 200. By August 1999, there were 180 adult horses and colts on the range. In May 2009, after several long-term studies of the rangeland, The BLM determined that the range's maximum carrying capacity was 179 feral horses. This assumed that all BLM land, as well as lands leased from other owners (public and private), would continue to be available to the animals, and that BLM would be able to manage the horses by using artificial watering sites to encourage the horses to utilize undergrazed portions of the range. The BLM also said it would implement other range management techniques The BLM also proposed purchasing 1467 acres (593.7 ha) of land from the state of Montana, and another 632 acres (255.8 ha) of private land, to add to the range.
At the same time, BLM said it would reduce the herd from its existing 195 adults to 120. The stated goal was to temporarily remove horses from the refuge to allow the range to recover from the historic overgrazing caused by livestock, not because BLM believed there were too many horses on the range. Sixty percent of the remaining horses would be males, to reduce the rate of population growth. The agency said it would remove 30 horses a year from the herd and stable them at a yearly cost of $18,000 to $21,000 until the correct herd size and sex ratios had been reached. Horses to be removed from the herd included those which did not closely fit the conformity type; which were genetically well-represented; which were 11 to 15 years of age, had sired or foaled, and were not band stallions; and were between five and 10 years of age or 16 to 20 years of age. Genetic diversity would be measured by visual observation of the herd's conformity to type using a visual system developed by Dr. Sponenberg, and measures taken to improve genetic diversity if signs of inbreeding occurred. The Cloud Foundation and Front Range Equine Rescue, both feral horse advocacy groups, challenged the roundup in federal court. A federal district court judge delayed the roundup three days to consider their request, but on September 2, 2009, rejected the injunction and allowed the roundup to proceed. BLM began its roundup of feral horses on the Pryor Mountains range in early September 2009. After several days, 130 of 188 feral horses were rounded up. Forty-six horses were put up for adoption, while the freed mares were given a contraceptive vaccine to help keep the herd population down.
At this time, BLM also placed "guzzlers" on the range. A guzzler is a precipitation (usually rainwater) collection device which traps water in a storage tank ranging in size from a few to several thousand gallons. The storage tank can be above-ground, partially buried, or below-ground. A mechanical valve releases water into a drinking trough from the storage tanks, allowing animals access to the water. When the valve senses that the water level in the trough is low, it opens and allows more water into the drinking area. Five guzzlers were placed in undergrazed areas to encourage the horses to better utilize this forage.
In the fall of 2010, BLM issued a set of draft strategy documents for operating its wild horse programs, and solicited public comment on the plans. After receiving numerous comments, BLM said in February 2011 it would quicken the pace at which it made revisions to its roundup procedures, use of fertility control drugs, and wild horse and burro range land management. The agency also commissioned a study from the National Academies of Science (NAS) on wild-horse management. Due for release in 2013, independent NAS experts will study a wide variety of issues, including the carrying capacity of wild horse and burro ranges, wild horse and burro population growth, and best practices in fertility control.
In September 2011, BLM announced it would begin working with the Humane Society of the United States
Humane Society of the United States
The Humane Society of the United States , based in Washington, D.C., is the largest animal advocacy organization in the world. In 2009, HSUS reported assets of over US$160 million....
to develop new practices in herd management and roundup, and increase its emphasis on adoptions and the use of drugs as fertility control to help better manage its wild horse herds.
Tourism
The Pryor Mountains feral horse herd is one of the most accessible feral horse herds in the United States. Tourism to the range increased steadily in the mid to late 2000s. The range can be easily accessed via a paved road which parallels Bighorn Canyon, and which provides excellent viewing of the horses. The range can also be accessed from Laurel, MontanaLaurel, Montana
Laurel is a city in Yellowstone County, Montana, United States. It is part of the Billings, Montana Metropolitan Statistical Area, and is located in the Yellowstone Valley, as an east-west terminal division point of the Burlington-Northern Railroad.. The population was 6,781 at the 2010 census.Both...
, by traveling south on U.S. Route 310
U.S. Route 310
U.S. Route 310 is a spur of U.S. Route 10. It runs for from Laurel, Montana to Greybull, Wyoming. It passes through the states of Montana and Wyoming. Near the town of Lovell, Wyoming, US 310 is concurrent with U.S. Route 14A for approximately three miles....
and then taking the Forest Service gravel road to Dryhead Overlook. Some of the range may be accessed via the Crow Indian Reservation
Crow Indian Reservation
The Crow Indian Reservation is the homeland of the Crow Tribe of Indians of the State of Montana in the United States. The reservation is located in parts of Big Horn, Yellowstone, and Treasure counties in southern Montana...
. A trespass permit from the Crow Nation is required to cross tribal land or exit a vehicle while on tribal land. Hiking on the Pryor Mountains Wild Horse range is good, but there are no maintained or marked trails and (as of 2000) no guidebooks to the area.
Sources
- Cruise, David and Griffiths, Alison. Wild Horse Annie and the Last of the Mustangs: The Life of Velma Johnston. New York: Scribner, 2010.
- Dutson, Judith. Storey's Illustrated Guide to 96 Horse Breeds of North America. North Adams, Mass.: Storey Publishing, 2005.
- Fischer, Carol and Fischer, Hank. "Montana Wildlife Viewing Guide. Helena, Mont.: Falcon, 1995.
- Hill, Cherry and Klimesh, Richard. Horse Hoof Care. North Adams, Mass.: Storey Publishing, 2009.
- Lynghaug, Fran. The Official Horse Breeds Standards Guide. Minneapolis: Voyageur Press, 2009.
- Massingham, Rhonda. Among Wild Horses: A Portrait of the Pryor Mountain Mustangs. North Adams, Mass.: Storey Publishing, 2006.
- Rowles, Genevieve. Adventure Guide to Montana. Edison, N.J.: Hunter Publishing, 2000.
- Singer, Francis J. and Schoenecker, Kathryn A. Manager's Summary—Ecological Studies of the Pryor Mountain Wild Horse Range, 1992-1997. Fort Collins, Colo.: U.S. Dept. of the Interior, U.S. Geological Survey, 1997.