Hunters
Humans are humans that know that the supernatural creatures exist and they hunt them. They see these creatures as monsters and a threat to the human race. Hunters are completely blind to the possibility that like humans, not all vampires, witches and shapeshifters are evil killers. They are usually fuelled by anger or revenge after the death of family, a friend or a loved one.
Hunters rarely work alone due to them only having normal human strength. Shapeshifters and vampires both have quick reflexes and super-human strength, and witches have magic. The Hunters match this with planning, weapons and working together to achieve their goals. So they are usually found in pairs or groups of a maximum of 6. Some Hunters have a large support network and are in contact with other Hunters across the country.
Not every human that has lost someone to a vampire, witch of shapeshifter will become a hunter. Some get themselves killed by attempting to kill them on their own. Those that do become hunters usually catch the attention of another Hunter who takes them under their wing and teaches them all they know. Hunters are trained in self-defense, or a martial art, usually taught in the same style their mentor uses. They carry with them a variety of weapons, and know how to use them. In larger groups of Hunters it is not uncommon for specific members to be the expert in different tasks.
Although Hunters are athletic, trained and skilled in tracking and identifying supernatural creatures, they cannot tell straight away who is not human. It takes weeks of watching and following, (some of which will be unsuccessful since vampires and shapeshiters will notice them easily) to identify someone as a non-human. Witches are the hardest to identify since they look and act human, and the popularity of new age practises and religions means it's not so easily to tell a witch and a human a part.