Trappers in the interior have a habit of narrating. When they encounter something they cannot explain, they reach for pattern and story rather than silence. Nix has benefited enormously from this tendency.
The legends
The most common account holds that Nix appears before a significant crossing and leads the traveler to water. A competing account holds that he leads travelers away from water, as punishment for unnamed transgressions.
The third account, held mostly by a single trapper who prefers not to be named, is that he is just a raccoon who has learned that humans carry food.