Advocacy Groups Urge BLM to Expand PZP Use for Wild Horse Management

More than 30 wild horse advocacy groups are asking the Bureau of Land Management (BLM) to reduce the number of wild horse gathers and increase the use of the contraceptive vaccine porcine zona pellucida (PZP) to manage herd population growth. This call to action comes in response to the BLM's announcement of a significant revenue shortfall, largely due to the costs associated with caring for horses in long-term holding facilities.

The groups' petition follows theBLM's revelation that thecost of caring for thousands of horses residing in long-term holding facilitiesis a major factor in a $1 billion revenue shortfall.

On June 1, 34 wild horse advocacy groups—including the American Wild Horse Conservation (formerly American Wild Horse Preservation), the Corolla Wild Horse Fund, Habitat for Horses, and the Salt River Wild Horse Management Group—called on theBLMto increase its use ofPZPin wild herds. The groups maintain that expandingPZPuse will reduce the need for horse gathers and the maintenance of horses in holding facilities.

Tom Gorey,BLMsenior public affairs specialist, stated that the goal of theBLM’s Wild Horse and Burro Program is to ensure the health, safety, and welfare of animals on public rangelands, and that the agency is committed to applyingPZPto the maximum extent feasible. However, he noted that because most of the agency's 177 herd management areas (HMAs) are so expansive, darting animals in the wild withPZPwould be logistically difficult.

Bait trapping is a viable option in some areas where water is limited, he said, “but in most HMAs, the horses move from one watering hole to the next over an expansive area, avoiding the traps and, thus, necessitating helicopter-assisted gathers for large-scale treatments.”

There are also budgetary limitations on expandingPZPuse, he said.

Meanwhile, not all wild horse advocates agree thatPZPis the answer to wild horse overpopulation. For instance, Karen Sussman, president of the International Society for the Protection of Mustangs and Burros, said a 16-year study of four wild horse herds her group conducted showed that when wild horse social structures are not disturbed, herd growth is as low as 7% under the best feed conditions.

She also believes expandingPZPuse will have unintended consequences for wild herds: “The use ofPZPwill push these wild species toward lower genetic viability and eventual extinction since permanent sterility results in as little as four years of application.”

While the debate continues, Gorey said theBLMis “open to new public-private partnerships that would expand the use of this vaccine.”

Originally posted by The Horse