Yellowstone National Park biologists are recommending that 450 bison, primarily females, be killed this winter to “reduce abundance and growth potential” in the northern herd. The statement was part of the operating procedures outlined at the November meeting of the agencies participating in the Interagency Bison Management Plan. The park’s bison herd was estimated in 2012 at 4,200 animals. That’s composed of two main groups, the central herd that gathers close to Old Faithful and the Firehole and Madison river drainages, and the northern herd that populates the Lamar Valley and Yellowstone River drainage. The Park Service would prefer to have a Yellowstone bison population of about 3,000 animals. At least one conservation group, The Buffalo Field Campaign,” is actively opposing the action.