They've survived in the wild for half a millennium, but now a development boom is threatening the very existence of the wild horses that roam the Outer Banks of North Carolina. And life isn't much better for the horses and burros that roam freely in the western United States, either.
On the East Coast, just 80 years ago, as many as 6,000 horses galloped unbridled along the northern Outer Banks of the Tar Heel State. But now the herd there numbers roughly 115 -- and a federal government-backed plan has been designed that will reduce it almost by half, to no more than 60, in an effort to stop the horses from competing with protected birds for hard-to-come-by natural resources.
In Corolla, N.C., a barrier island without roads and a permanent population of just several hundred people, a boom in vacation homes in the last quarter century has seen the descendants of colonial Spanish mustangs confined to a 7,500-acre sanctuary on the northern tip of the Outer Banks. The acreage is too small for the horse population, which has led to a campaign to reduce the size of the herd. It's an effort that U.S. Fish and Wildlife Service officials say will reduce harmful behavior by a species it considers a nuisance.
But advocates who rely on the animals to bring in tourist dollars or simply marvel at their beauty say the plan will lead to hereditary diseases and other complications, due to an artificially shallow gene pool.
Karen McCalpin, executive director of the Corolla Wild Horse Fund, says that further shrinking the herd, as federal officials plan to do, will have potentially disastrous effects, including widespread inbreeding and dwarfed animals. In fact, McCalpin said she's already seeing those signs now.
"We're there now," she told FoxNews.com. "The only way to turn that around is to introduce horses from Shackleford who would bring new genes into this dying gene pool."
"In layman's terms," she said, "these horses are all incredibly closely related to each other. When you don't have genetic diversity, you start to see horses with issues with eyesight, horses that are dwarves. We're also seeing a lot of horses with locked patellas (kneecaps)."
McCalpin has her hopes set on a bill introduced in Congress by Rep. Walter Jones, R-N.C., that would set a target population of between 120 and 130 horses and allow the introduction of mares from Shackleford Banks -- on the southern end of the Outer Banks -- to enhance genetic diversity.
"The American wild horse is dying in our country," she said on Monday. "They built our country on their backs and I think it's incredibly important to protect that part of our history."
McCalpin estimated that up to 60,000 people descend upon the Outer Banks during summer weekends, some to see the natural beauty of the wild horses. She's hopeful that interest will lead to greater protection for wild horses that were once found in large herds throughout the Southeast but are now limited to just a handful of isolated spots in Maryland, Virginia, North Carolina and Georgia.
"If I wasn't hopeful, I wouldn't be doing this job," she said. "We've reached a point where we've been able to create enough awareness for the need to protect these horses."
Wild horses are in a similar predicament in 10 Western states, where 33,700 horses and 4,700 burros currently roam, according to the latest federal data available from February. That figure exceeds by nearly 12,000 the appropriate level that the Bureau of Land Management (BLM) has determined can exist in harmony with other public rangeland resources.
Overpopulation of the wild animals leads to soil erosion, sedimentation of streams and damage to wildlife habitat and has forced officials to conduct ongoing adoption drives and roundups in 10 states.
"Wild horses and burros have virtually no natural predators and their herd sizes can double about every four years," a BLM website reads. "As a result, the agency must remove thousands of animals from the range each year to control herd sizes."
Off the range, more than 34,500 wild horses and burros are fed and cared for at short-term corrals and long-term pastures, according to BLM data. All wild horses and burros in holding, just like those roaming the public rangelands, are protected under the 1971 Wild Free-Roaming Horses and Burros Act.
Due to the overpopulation, Tom Gorey, a BLM spokesman, said the agency is conducting roundups in 10 states, including Nevada, Oregon, Utah and Idaho. They are also offering wild horses for adoption for just $125, but adoptions are down roughly 40 percent nationwide since 2005.
"We are looking at a declining market," Gorey told FoxNews.com. "What we seem to be facing is a tough economy, which makes taking on a horse undesirable because of expense. The market is very soft; we're trying to bolster adoptions."
Gorey said federal officials are trying to get the free-roaming population down to 26,000 nationwide, an effort that, when factoring in annual population growth, would require removing about 11,000 from the wild every year.
BLM officials will conduct an Internet adoption on Oct. 20. Until then, visitors can peruse an online gallery of wild horses and burros currently available. In-person adoption drives will take place beginning on Oct. 22 in Lorton, Va., with other events planned in Murfreesboro, Tenn., Archdale, N.C., Oneonta, Ala., and Lake Charles, La.
In fiscal 2009, BLM officials removed 6,413 wild horses and burros from public rangelands and placed 3,474 of those animals into private care through adoptions, down from 5,701 in fiscal years 2005. More than 225,000 horses and burros have been adopted via BLM officials since 1971.
According to fiscal 2010 populations, more than 17,000 wild horses were counted in Nevada, roughly four times the number in Wyoming, the next most-populous state. Given the declining market for adoptions and booming population levels, Gorey said it's not going to be easy to reach appropriate levels.
"We're trying to get it down to 26,000," he said on Monday. "It's a challenge to get down to that level."
The Associated Press contributed to this report.
For more information on how to adopt a horse from the Bureau of Land Management, click here.