Adult Description
- Medium-sized to small waterbird.
- Thin, straight bill.
- Large white wing patches crossed by black bar.
- Bright red feet.
- Relatively long, thick neck.
- All black with white wing patches in summer.
- Mostly white with dusky back in winter.
Immature Description
Similar to nonbreeding adult, but with more mottling on head and neck, and black markings breaking the white wing patches.Relative Size

crow-sizedMeasurements
- Both Sexes
- Length: 11.8-13.8 in (30-35 cm)
- Weight: 15.9-19.4 oz (450-550 g)
- Wingspan: 21.6-23.2 in (55-59 cm)