There are many behaviors a buck will exhibit during the rut. During pre-rut, bucks will spar with each other. Sparring is low-intensity aggressive behavior, involving mostly pushing and shoving. Bucks of different sizes will do this to each other. After pre-rut is finished, a buck will rub his antlers on a tree (thus making a "rub"), and make scrapes on the ground with his hooves: both of these are ways a buck will mark its territory and proclaim his dominance for other bucks to see. These activities are usually done at night.