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Bison Identification Exam Photo

Few people have the opportunity to hunt bison in North America, much less in a setting as beautiful as northwest Wyoming. Hunting is a very personal experience and the WGFD wants you to enjoy it to the fullest. In order to do so we want you to be safe, ethical and legal. Without practice, it can be difficult to tell cows from bulls. If your license is valid for a specific sex of animal (i.e. Type 4 female/calf wild bison) it is important that you can differentiate between bulls and cows. A one to two year old bull and a mature cow are difficult to distinguish. If you have a cow license, pay particular attention to the animal’s head. Generally, bulls are considerably larger animal with more massive horns. Yearling bulls have horns that have a larger diameter base and grow outward more than female bison. Cows have similar shaped horns but are typically much thinner and slightly more curved. Along the underside of the animal, the penis sheath of a bull is usually evident on older bulls.

Below is a table comparing the common characteristics of bison followed by an educational quiz that will help you identify the sex and age of bison in the field. Take the quiz, enjoy the learning experience and good luck! The quiz consists of 14 multiple choice questions.

Identifying Characteristics
Cow Mature Bull Yearling Bull
Penile sheath missing
Horns thin at base
Horns curve inward

Head narrow
Body smaller less muscular
Neck noticeable
Penile sheath present
Horns heavy at base
Horns have less inward curve but there are exceptions to this.
Head broad, triangular darly and wooly
Body large,stocky and muscular
Shoulder and head seem to merge, no neck
Penile sheath may not be visible
Horn thickness intermediate
Horns jut out at an angle

Head intermediate
Body smaller less muscular
Neck noticeable
Click here to take the Bison Identification Exam
Remember there are exceptions to every characteristic so use several to make your determination.
For cows look specifically for:
1) The absence of a penile sheath
2) Horns that are thin at the base
3) Horns curving inward. However realize that some bulls have highly curved horns. Use the basal diameter of the horn to help judge.

Stay away from:
1) Heavy horns
2) Horns with no inward curve
3) Horns that jut out at an angle

Young bulls are sometimes mistaken for cows. Their horns are beginning to curve and the base circumference is similar to that of older cows. Remember take your time and don’t take chances.

Please do not approach an agitated bison. Typical signs of agitation include raising of the tail, snorting and scraping of the ground with the front hooves.