Family Oystercatchers (Haematopodidae)

Least Concern

Blackish Oystercatcher (Haematopus ater)


French: Huîtrier noir German: Klippenausternfischer Spanish: Ostrero negro americano

Haematopus ater


, 1825,

Straits of Magellan


Some hybridization with H. palliatus recorded in zone of overlap; has hybridized also with H. leucopodus#R. Race bachmani has normally been considered a separate species, but the two are almost identical in plumage and voice, apparently differing only in greater depth of bill of nominate ater. Two subspecies recognized.

Subspecies and Distribution
  • H. a. bachmani Audubon, 1838 – W Aleutian Is (Kiska I) through S Alaska (including Round I), W Canada and W USA to NW Mexico (Los Coronados Is and Baja California). Outside breeding season, mostly concentrated between S British Columbia and Baja California.
  • H. a. ater Vieillot, 1825 – N Peru (Lambayeque) S through Chile to Tierra del Fuego and N up Atlantic coast to SC Argentina (Chubut); Falkland Is. Outside breeding season some move N to extreme N Peru, NE Argentina and probably Uruguay.
  • Descriptive notes

    43–45·5 cm; 585–850 g (nominate), male 555–648 g, female 618–750 g (race bachmani); wingspan c. 80 cm. Heavily built, all-dark... read more


    Most-frequently heard call a repeated over-slurred piping whistle, “peep” or “kleep”. During... read more


    Breeds on pebble and shell beaches. Outside breeding season occurs on shingle and rocky shores, as... read more

    Food and feeding

    Very few data for South American nominate, which is known only to feed mainly on mussels and limpets on rocky shores. Diet of race ... read more


    In nominate race, laying mostly starts in Nov, in Tierra del Fuego; late Oct to late Jan, on Falkland Is; May–Jun in N America (race... read more


    Mainly sedentary. Birds breeding in extreme S (Tierra del Fuego) move an unknown distance N after... read more

    Status and conservation

    Not globally threatened (Least Concern). Occurs at fairly low density throughout range and is considered a species of high conservation concern in both USA and Canada, but... read more

    Recommended citation

    Hockey, P., Kirwan, G.M. & Boesman, P. (2020). Blackish Oystercatcher (Haematopus ater). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 1 April 2020).