This week ended with an announcement by the federal government that may turn out to be a historic step forward in our efforts to protect the nation’s remaining free-roaming wild horses and burros. Today, the Environmental Protection Agency (EPA) announced the official registration of the first contraceptive vaccine for horses in the United States, called ZonaStat-H (more commonly referred to as porcine zona pellucida or PZP). The Humane Society of the United States sponsored the registration of the vaccine. The EPA registration means that the vaccine, which has been used on Assateague wild horses for more than 20 years, can now be used by wild horse managers for all the Western herds.
The federal management program for wild horses has been something of a financial and animal welfare disaster for quite some time. In recent years, the BLM has rounded up tens of thousands of horses, causing distress and fear and some occasional deaths, without any reasonable expectation to adopt out these animals. That has resulted in a swelling captive population of wild horses―now more than 45,000. Almost half of the agency’s entire budget goes toward captive horse management.
If there is pressure or reason to reduce the population, then the primary management tool from this point forward should be fertility control, rather than costly and sometimes dangerous round-up and removal regimes. PZP is now ready to be used for this purpose. The contraceptive vaccine prevents female horses from becoming pregnant, and it is safe for the animals and the environment. Above all, it can be used to maintain sustainable populations, since the American public wants wild horses roaming the West. By using more fertility control to humanely reduce wild horse populations on the range, and having fewer horses in long-term federal holding pens on the government dole, U.S. taxpayers can save tens of millions over the next decade.
PZP was first used on wild horses in 1988 when a team led by Jay F. Kirkpatrick, the director of the Science and Conservation Center in Montana, began a pilot project on the famous wild ponies at Assateague Island National Seashore off the coast of Maryland. This project was very successful and has now led to the current PZP study we’re conducting in partnership with the Bureau of Land Management (BLM) with a grant from the Annenberg Foundation. The HSUS is working with the BLM t to develop longer-lasting and more easily administered versions of the vaccine.
The HSUS has forged partnerships with public agencies, communities, parks, zoos, and other groups to test PZP to safely manage wildlife numbers. The vaccine has also been used to help control elephant populations in South Africa, deer in suburban areas, and dozens of species of zoo animals.
The importance of technological advances to animal welfare cannot be overstated. It has been said that Henry Ford did even more for horse welfare than Henry Bergh (the outstanding 19th century humanitarian and ASPCA founder) as millions of overworked and suffering horses were gradually replaced in the early part of the 20th century by motorized transports in cities and on farms. In the same vein, we’re delighted to have helped bring this new technology to the forefront of wild horse and burro management in the United States. On August 28, we’ll be hosting a conference in Jackson Hole, Wyoming, focusing on the use of innovative management tools, such as ZonaStat-H, to manage wild horse populations. If used properly, this innovation has the potential to allow our nation to turn the corner on this problem and meet the needs of everybody who cares about preserving wild horse and burro populations in the West.