Visitors to the Sand Wash Basin area north of Maybell may notice bait stations and other activity this summer and fall related to keeping the wild horse population in the area healthy, the Bureau of Land Management reported in a news release.
The BLM and the Humane Society of the United States have partnered for an ongoing research project looking at the feasibility of reducing the reproductive rate in the wild horse herd in the Sand Wash Basin through the use of a vaccine.
Two years ago, during a wild horse gather, 62 mares in Sand Wash were treated with a fertility control vaccine and released. This vaccine, called PZP, was projected to prevent pregnancy in the mares for two years.
This summer, as the vaccine begins to lose its effectiveness, the mares will be given a booster dose of the vaccine remotely using dart rifles.
“Wild horse populations in the West can double every four years because they have no effective predators,” said Dave Blackstun, the acting Little Snake Field manager, in the release. “We periodically conduct gathers to keep wild horse populations in check, and BLM is also researching the effectiveness of using fertility control vaccines like PZP.”
PZP is designed to delay fertility in mares to reduce the growth rate of the wild horse population, but not to sterilize them.
Reducing the growth rate should reduce the frequency that expensive wild horse gathers are needed.
To efficiently treat as many mares as possible, bait stations will be constructed around water sources in Sand Wash.
Jute netting will be hung from T-posts for approximately 150 feet to guide the horses into the water. Hay, oats and salt blocks will be placed near the water to entice the horses to linger in the area, giving the trained darters an opportunity to deliver the vaccine.
It is anticipated that the project to deliver the booster vaccine to the 62 mares will continue through September or October.
The BLM has supported fertility control research for wild horses since the 1970s, hoping in particular that a single-shot vaccine providing multi-year effectiveness would be developed.
“By continuing our partnership with the Humane Society of the United States, BLM hopes to build the scientific, technical, and regulatory foundation for the use of the PZP vaccine as a safe and effective tool for helping control the growth of wild horse populations on Western public lands,” Blackstun said.
The BLM manages the 160,000-acre Sand Wash Herd Management Area for up to 362 wild horses.
For more information about BLM’s wild horse and burro program, or to find out how you can adopt a wild horse or burro, log onto www.blm.gov.