Plump, black or pied, stricktly coastal shorebirds with short, sturdy red legs and robust, laterally flattened bills, adapted for prising open limpets and mussels.
They roost communally at high tide in safe, highly raised areas with good visibility.
Foraging times are dependent on when the tide exposes feeding areas, and they are therefore active da or night.
They are monogamous with protracted pair bonds. Pairs make a nest-scrape on the groun, preferring islands, where there are no terrestrial enemies. They lay 1 - 3 buffy eggs spotted and splotched with black and brown. Incubation and care of young is done by both adults. The checks may swim and dive to avoid danger.

Haematopus = blood foot, in reference to red feet and legs

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