MUSTANG MANAGEMENT CROSSROADS

Free-roaming wild horse herds have long been emblematic of the American West. Though legislation has placed the animals under federal protection, finding the best way to keep them and their ranges healthy has been challenging. Now, a diverse coalition of wild horse welfare advocates, ranching organizations, rangeland advocates and state governments have come together to create a plan they believe can promote the horses’ well-being for years to come. But not all wild horse advocates believe that the plan will benefit the animals in the long run.

The Roaming Wild Horse and Burro Act of 1971 protected wild horses and burros and placed them under the jurisdiction of the Bureau of Land Management (BLM). Today, more than 80,000 horses reside on Herd Management Areas (HMA) in 10 western states. Nearly 37,000 more roam 289,000 acres of grasslands in long-term pastures, and approximately 12,000 reside in short-term holding corrals.

solutions For growing numBers

With some herd sizes estimated to double every four years, some ranching and rangeland advocacy groups have argued that the growing sizes of on-the-range the Mustang herds compromise ranges by competing with domestic cattle, sheep and goats for resources on public grazing lands.

In response, the BLM and some welfare advocate organizations have investigated ways to control herd growth without allowing the BLM to sell gathered horses “without restriction”—that is, to buyers who would sell the animals for meat/slaughter. Population control measures have included the use of the contraceptive vaccine porcine zona pellucida (PZP) on mares. The BLM has also investigated surgical sterilization of mares.

According to Tom Lenz, DVM, MS, DACT, member of the BLM’s Wild Horse and Burro Advisory Committee, expanding the use of PZP on wild mares is difficult partly because some herds are just inaccessible to humans.

“Right now, [the BLM] is vaccinating 1,000 mares a year, and those are the ones they can get close to,” says Lenz. “The proposal is to vaccinate 90 percent of the mares, but some of those herds have never seen a person. How are you going to vaccinate them?”

Even if PZP use is increased, it will probably be years before the desired population control will be realized.

“The Assateague horses are a good example,” says Lenz. “In 1993, they decided that the herd was too large at 156 animals, and that was in a tourist area where the horses were used to moving among people. Thirteen years later, the herd was down to 143 horses, and it took 20 years to get to 120. I don’t [see how] the BLM could do it.”

meeting to Find common ground

In April, a diverse group that included the American Society for the Prevention of Cruelty to Animals (ASPCA), Return to Freedom wild horse sanctuary, the Humane Society of the United States (HSUS), the Humane Society Legislative Fund, the National Cattlemen’s Beef Association, the Public Lands Council, the American Farm Bureau Association, the Society for Range Management, and other diverse stakeholders