🐂 The Bison Rut: A Fascinating Natural Phenomenon 🐂 Timing of the Rut The bison rut typically occurs in late summer to early fall, usually from late July through September. Behavioral Changes During the rut, male bison (bulls) become more aggressive and vocal. You may hear deep grunts and bellows as they compete for dominance and the attention of females (cows). Physical Changes Bulls develop larger muscle mass and can gain up to 200 pounds in preparation for the rut. Their fur may also appear

American Bison Habitat: From Majestic Creatures to Habitat Heroes