Fearing to go near suspected Bunyip haunts, the Aborigines shared their fearsome legends with early white settlers. After hearing such tales, they became fearful of strange, loud noises at night, and seriously considered the existence of the Bunyip Monster.

Descriptions of Bunyips include a wide spectrum of appearances from animal to spirit. Some describe the Bunyip as a gorilla-type animal (kinda like bigfoot, or the Australian Yowie), while others say it is half animal, half human or spirit. Bunyips come in all sizes, shapes, and colors. Some are described to have long tails or necks, wings, claws, horns, trunks (like an elephant), fur, scales, fins, feathers...any combination of these.

Although scientists have found no physical evidence of Bunyips, they suggest it could have been a diprotodon, which became extinct 20,000 years ago. It frightened natives even after it's extinction, spawning horror stories that have made it such a feared creature.

Another circulating theory is that the modern Bunyip encounters originated (unintentionally) from wanderers or those who went off into the Australian wilderness during the Great Depression, or to escape hardships or the law. To prevent discovery, they would hide from others by creating a make-shift snorkel out of bone and hiding underwater. If they popped out before the unwanted guests left, it would make for quite a scare on both sides. And the startled cry of the one in hiding could cause the frightened passers-by to think they encountered a Bunyip. As for their affinity for women, this could be explained by the wanderers long periods of time alone, without contact with women, and when one came along, it made for an irresistible opportunity.