Controlling the wild horse population has been a challenge for the Bureau of Land Management.  Jay Kirkpatrick with the Science and Conservation Center has been using a vaccination to control the reproduction of wild horses on federal rangelands. Last month, after over 2 decades of use EPA announced the registration ZonaStat-H, the first contraceptive vaccine approved for horses.

AUDIO: Jay Kirkpatrick, The Science and Conservation Center (3:00mp3)