What is bellowing?

Bellowing is a loud, deep, and resonating sound produced by animals, especially male animals during mating season or when threatened. It is a form of communication used by several mammals such as moose, elk, deer, and bulls. Bellowing typically involves the activation of the larynx and the production of a loud and vibrating sound through the animal's vocal cords. The sound can travel long distances and can serve to attract mates, warn off predators or establish territory. Bellowing is often accompanied by a physical display such as head tossing, pawing, or antler rattling.