"THE WILD MUSTANG IS NOT NATIVE TO NORTH AMERICA"......... “Wild horses” are feral descendants of imported domesticated European horses that escaped from ranches and Indian villages from AD 1500 up through the 19th century"............ "These herds roam freely in dedicated ranges scattered throughout the West and outer banks of North Carolina".......... "Mustangs only real enemy today is lack of resources and disease as there are not nearly enough Wolves, Grizzlies and Pumas to impact their numbers".............. "The last prehistoric North American horses died out between 13,000 and 11,000 years ago along with Saber-tooth cats and Dire Wolves, at the end of the Pleistocene era".............."The U.S. National Park Service, US Fish and Wildlife Service, and the Bureau of Land Management have a legal mandate to protect native wildlife and prevent mustangs from destroying the ecology of the land"..............."The number of wild horses and burros that can live in balance with the ecology of U.S. public lands is 27,000"..........."Currently, there are an estimated 82,000 wild horses on the landscape"............. "Colorado State University’s GonaCon vaccine could offer lasting results for managing wild horse population".........."The vaccine prevents the mares from ovulating and from displaying sexual behavior, thus eventually limiting the number of foals born annually"

https://phys.org/news/2016-11-feral-horses-ongoing-states.html

https://phys.org/news/2019-10-wild-horse-problem-5b-years.html

NOVEMBER 29, 2016; by Elsevier

Management of feral horses an ongoing challenge in the United States

Feral horses are free-ranging descendants of once-domesticated horses. All free-ranging horses in North America are feral horses, and between 2014 and 2015 the feral horse population in the United States increased 18% according to the Bureau of Land Management (BLM). In 2015, the number of feral horses in the western ranges of the United States alone was estimated at 58,150. With few natural predators, populations will continue to rise, doubling every four years; thus, managing populations of feral horses represents a unique challenge in the United States

"The ever-expanding population of feral horses is a critical but not simple problem to solve," said Lori L. Ward, lead author of a recent review of the feral horse issue in The Professional Animal Scientist. "Any solution to this problem must have an understanding of current populations of horses in each ecosystem, the carrying capacity of the ecosystem, and consideration of how these numbers will naturally vary."

In the 1950s, to combat rising populations, many feral horses were slaughtered by various means, including poisoned watering holes. This solution was met with public outrage and led to congressional action in the form of the Wild Free Roaming Horse and Burro Act of 1971, which protected feral horses as a link to our national heritage. This act protected horses on federal land and kept them from slaughter, prompting new efforts at population control.

Since that time, BLM has herded animals into holding locations where they can be managed and adopted-out. Many horses do not get adopted, however, and are labeled unwanted; likewise, the process of rounding-up feral horses is expensive and costs to maintain captive feral horses are estimated to exceed $1 billion by 2030. Such rising costs may end the adoption practice in coming years, according to the BLM.

Another means to limit populations is contraceptive use. The practice is controversial, as animal welfare activists often do not agree with the use of contraceptives, but the United States Humane Society is in support of such measures. Contraceptives, such as porcine zona pellucida vaccine, castration, or vasectomy, have not been without side effects, however. These methods may only slow growth, or in the case of vasectomy have no effect on foal rates; likewise, they may disrupt seasonal patterns within the herds among other changes.

Perceptions of feral horses in the United States are numerous and multifaceted, which creates a unique challenge when it comes to managing their populations. In order to determine the most effective management practices, knowledge of horse population dynamics as well as public political views are necessary. Any solution to such an issue can only be gained by continued research.