Yellowstone National Park officials announced today that on Wednesday evening, March 31, 2004, a two-year old female bison being held at the Stephens Creek facility delivered a stillborn calf. A necropsy at an animal disease diagnostic lab is pending to determine more about the circumstances that may have lead to the stillborn delivery.

On Wednesday afternoon, park staff noticed the female bison was beginning to display evidence of the birthing process. The animal was segregated from the other bison in an adjacent and separate holding pen, where the stillborn calf was subsequently delivered. The female bison continues to be segregated from the other bison until diagnostic results are known.

As with other wild, grazing animals, a certain number of bison are stillborn each year. Bison generally start giving birth around the third week of April. Although this particular birth was a little early, it is not unheard of.

Currently, there are 198 bison being held at the Stephens Creek facility for release back into the park when sufficient forage is available to keep them from exiting the park.

Information provided by the NPS