By Angus M. Thuermer Jr., WyoFile.com
YELLOWSTONE NATIONAL PARK — A bison calf lunges into the mechanical livestock squeeze chute, bucking and kicking, its lashing hooves and horns clattering against the metal frame. It struggles for half a minute, huffing, sometimes bleating in its alien enclosure. At the right instant, a Yellowstone National Park worker thrusts a lever and the “Silencer” squeeze chute closes its jaws, encasing the animal in a corset of metal bars and collars. With the bison immobilized, a biologist notes the animal’s age and condition and collects a blood sample. The Silencer weighs the animal and after a few minutes releases it to bolt down a maze of alleys in Yellowstone’s Stephens Creek corral complex.