Buffalo are fast, strong, and often unpredictable animals, but Indians understood bison behavior and used this knowledge effectively. For example, the Indians knew that manipulating herds of buffalo was easier than controlling individual animals. In late autumn, when most hunts occurred, bison were usually dispersed in small groups of cows and calves. After much planning and ceremony, scouts were sent out to gather the small groups into a critical mass of 200 to 500 buffalo and to position them within a few miles of the sinkhole.
When they sensed a threat, the bison naturally tended to seek the apparent safety of a large group. Scouts used various techniques to gently harass the small groups into one large herd without causing them to scatter, turn on their antagonists, stamped prematurely, or leave the area. Tribes are known to have used various kinds of decoys such as a man covered with a buffalo hide who positioned himself near the herd and pretended to be a calf in distress. Dominant cows would investigate and other buffalo would follow. The decoy would move closer to the trap. Buffalo would follow.