Rarely, feeds in nearby grass or cultivated grain fields. Flightless, molting adults prefer larger bodies of water over small ones, and escape by diving and swimming. Often nests on islands, usually surrounded by open water rather than emergent vegetation. Generally avoids waters surrounded by woods or dense brush, but will use clumps of brush as nesting cover. Drake usually waits for mate on bare shoreline, or on a rock or log.
Broods prefer larger bodies of water, with deep channels for escape.
No additional data found. Migrates night and day. Individuals that breed in northeastern California mostly winter elsewhere in California or Mexico. Individuals breeding elsewhere in California apparently nonmigratory, or at least the species is present year-round. Usually monogamous, but sometimes female changes mates during a single nesting cycle, and a tendency toward promiscuity in high density nesting.