Whoops

Whoop vocalizations are arguably the quintessential Sasquatch vocal and sound just like the name implies. The best executed whoops start low and ascend rapidly in tone and volume to end abruptly, but variations do exist. During the examination of whoop vocals considered by this effort, two basic forms of the whoop have been identified.

Interestingly enough, howling and whooping is also related to territory protection and mate guarding in primates. These sounds are created owing to their enlarged basihyal or hyoid bone, which helps them make loud vocalizations. … The main vocal sounds comprise of a loud, deep guttural cry or howl. The noisy primates are widely believed to be the loudest land animals.