(NOTE – Comments sought: The Billings Field Office of the Bureau of Land Management is seeking comment on a proposal to conduct fertility control on the Pryor Mountain Wild Horse Herd. Comments will be taken until May 7. To comment, write to Jim Sparks, field manager, at the BLM Billings Field Office, 5001 Southgate Dr., Billings, MT 59101. Or fax comments to 896-5281. To read a copy of the scoping letter, click here or see the attachment in this story at billingsgazette.com.}
The management of wild horse herds and flourishing urban deer populations is so politically charged that science often gets pushed aside, said Jay Kirkpatrick, of the Billings-based Science and Conservation Center.
Kirkpatrick, one of the founders of SCS, spoke to the Conservation Roundtable on Tuesday at the First Interstate Operations Center. His company, a nonprofit, creates a vaccine called PZP that acts as a contraceptive in wild animals.
Burgeoning wild horse populations on Western federal lands — including the Pryor Mountain and McCullough Peaks wild horse ranges — have led to controversial roundups and trapping of the horses to keep herds from growing unchecked.
Urban deer, finding safe havens in city parks and wooded areas, likewise have grown and required some cities to find ways to reduce their numbers. In Helena, deer are trapped and killed. In Glendive, Colstrip and Fort Benton, the deer can be hunted under special programs.
Kirkpatrick argued that these methods don’t address the underlying problem — reproduction. He said that removal of animals simply results in compensatory reproduction, which can lead to increased birth rates among the targeted animals.
PZP is a vaccine made from pig ovaries that, when injected into a female animal, causes her antibodies to attack. The antibodies also seek out the animal’s own eggs and prevent conception. Like any vaccine, the effects wear off and a booster is needed.
SCS proved the possibilities of the immunocontraceptive at Assateague Island National Seashore on the East Coast. In the Maryland portion of the park, PZP has kept the wild horse herd at a sustainable level without roundups or removals.
“We stopped growth overnight and it took several years to start to decline,” Kirkpatrick said.
The cost, he said, is roughly $106 to dart one horse. In the Pryor Mountains, he estimated the cost to remove one horse at $2,165.