Distinctive large chunky shorebird of rocky coasts, adjacent sandy beaches and river mouths. The only all-dark oystercatcher in South America, readily identified by wholly dark plumage, long orange-red bill, thick pinkish legs. Found as singles and pairs, less often small flocks (mainly when roosting), and associates readily with Magellanic and especially American Oystercatchers. Loud piping whistles sound similar to American Oystercatcher.