Skip to Main Content
It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
San Diego Zoo Wildlife Alliance logo
San Diego Zoo Wildlife Alliance Library logo

American Bison (Bison bison) Fact Sheet: Diet & Feeding

American Bison (Bison bison)


  • Bison are grazers; feed mostly on grasses.
  • Winter/summer diets differ in free-ranging populations. (Grizmeck 1990)
    • Add lichens and mosses to diet in winter.
  • When feeding on natural vegetation select many different grass and a few other plant species, varying with local habitats (Peden et al 1974)
    • Blue gramma (Bouteloua gracilis), sand dropseed (Sporobolis cryptandrus) little bluestem (Andropogon), windmill grass (Chloris), wild oats (Avena), wheatgrass (Agropyron), and Bromus Hierchloe, Elymus, Koeleria, Stipa, Phragmites, Distichlis, Hordeum, and Carex.
    • In Arizona bison ate 71% saltbush (Atriplex sp.) (Peden et al 1974)


  • Ruminant digestive system; four chambered stomach
  • Compared to cattle, bison extract more nutrition from low protein, highly fibrous plants. (Hawley 1981).
  • European bison have more browse in their diet in the wild. (Peden et al 1974)
  • Because American bison males in the wild lived mostly apart from the large herds, they were able to select the better-quality food and grow to very large size. (Guthrie 1990)

Page Citations

Guthrie (1990)
Hawley et al. (1981)
Peden et al. (1974)

SDZWA Library Links