A raven was seen resting at an overlook with a view of the Golden Gate Bridge, in the Marin Headlands just north of San Francisco. These birds are accustomed to living around humans. Ravens are sometimes mistaken for crows, but they are much larger. They are revered in some cultures, and in others are seen as omens of bad luck. Their numbers have been increasing, and there is disagreement as to the impact of their broadened habitat.