The early depictions of the Jersey Devil as a human show a large range of races (go figure in New Jersey). The default human form was more of a myth anyway. Many people just picture someone they very much dislike, and that’s kinda what the default Jersey Devil looked like to them.
The monster form is a lot more fun. It also is very highly debated because the creature seems different in every portrayal. People would pick out things like the teeth and only remember the teeth. Apparently the Jersey Devil does a lot of smiling, which is cute on a dog, not a walking monster.
This depiction was drawn by an artist who met with an apparent Jersey Devil victim and heard her description.