They possess abilities that far exceed those of a regular mage. However, they do not have the same raw potential of a true magician like Beranabus. Druids are greatly respected but also feared, which mostly stems for their solitary nature and superstition from normal humans.
Druids draw their magic primarily from the stars as well as partially from the sun and moon. Unlike their female counter-part Priestesses who draw their strength from the Earth and it's flora and fauna. Due to the source of their magic being the stars, they are more powerful at night.
Druids are exclusively male mostly because of the source of their magic. Men draw power more easily from the stars and beyond while women draw their power more easily from the Earth. However, there doesn't seem to be any discernible difference in strength or potential between the two.
"Male magic comes from the forces generated by the gods, the dead and the Demonata"
(Bec - pg 102)
There are only four known Druids, all mentioned in book 4 Bec: