GRAND JUNCTION — The Bureau of Land Management has no new wild-horse roundups planned for the remainder of this year and, in that lull, will be researching a new population-control measure — the promising but controversial spaying of mares in the field.
The BLM is laying out steps to study what are called ovariectomies. Initially, the agency is seeking input from veterinarians about the best way to conduct field spayings. If those veterinarians give the idea a green light, the BLM would try out the procedure in holding facilities, followed by research in the field, before implementing any widespread program.
“We will be proceeding on this soon. It’s a very high priority for us,” said Dean
Bolstad, the BLM’s wild horse and burro senior adviser.The BLM has had to take a new look at population-control measures because contraceptive drugs haven’t worked well to reduce herd sizes. Birth-control drugs are effective for less than two years and necessitate expensive repeat gathers of the animals. BLM wild-horse managers hope for approval of a more long-acting drug, but that is not expected anytime soon.
The agency is looking at new measures such as spaying because there is a lack of space for more horses in holding facilities, which are already home to more than 37,000 wild horses and burros. Last year, the BLM spent $43 million to maintain those animals in captivity. Adoptions of wild horses have dropped from 7,600 in 2001 to about 2,500 last year.
The ovariectomy became a seriously considered option after the BLM’s Wild Horse and Burro Advisory Board recommended — in an eight-page “Population Growth Suppression Alternative” paper last fall — that it be studied.
The advisory board laid out reasons why removing the ovaries of some mares could be an important part of controlling the population of wild horses in herd-management areas and how it could be done in a more humane way than the roundups the BLM has long relied on to thin herds.
The board recommended using water and food as bait to corral horses long enough to treat them.
“Anytime you can get the BLM to consider something new, that’s good,” said Tim Harvey, the wild-horse advocate on the national advisory board.
Harvey pointed out that ovariectomies are already a government-approved measure and have been used safely on race horses.
“Personally, I do think it can be safe in the field,” said advisory board chairman Dr. Boyd Spratling, who is a veterinarian from Nevada.
Spratling said there are many factors to consider before spaying trials could begin. Those factors include deciding the best age to spay mares, determining whether the procedure could be done laparoscopically, and figuring out the best way to anesthetize the animals and treat them with antibiotics afterward.
Wild-horse activists have blasted the idea of ovariectomies, saying that spaying mares in the field would amount to “mutilation.”
In 2011, the BLM planned to spay mares that had been rounded up before returning them to a herd-management area in Wyoming, but it backed off, saying that more research needed to be done.
The BLM soon will have some of that research when the National Academy of Sciences weighs in on spaying as a wild-horse management tool. The academy is expected to release a study next month that will address a number of issues the BLM is dealing with in its attempts to manage wild horses and burros.
The BLM asked the academy to assess the current contraceptive drugs being used and to look into whether spaying, castration or vasectomies should be considered.
“We are going to proceed carefully and responsibly,” Bolstad said.
Nancy Lofholm: 970-256-1957, nlofholm@denverpost.com or twitter.com/nlofholm