The word dude (or the now-archaic term greenhorn) indicates an individual unfamiliar with cowboy culture, especially one who is trying to pretend otherwise.
Several of the series shows have featured greenhorn fisherman who are usually the brunt of harsh criticism and sometimes bullying by veteran deckhands.
On frigid nights around bunkhouse stoves, the greenhorns were terrified by grizzled old veterans who swore they had fought off such monsters during previous winters.