Family Ducks, Geese, Swans (Anatidae)


Blue Duck (Hymenolaimus malacorhynchos)


French: Canard bleu German: Saumschnabelente Spanish: Pato azul

Anas malacorhynchos

J. F. Gmelin

, 1789,

Dusky Sound, South Island, New Zealand


Race hymenolaimus has been regarded as of uncertain status, and generally not accepted; recent phylogeographical study, however, revealed strong genetic differences between North I and South I populations#R. Two subspecies recognized.

Subspecies and Distribution
  • H. m. malacorhynchos (J. F. Gmelin, 1789) – W South I, New Zealand.
  • H. m. hymenolaimus Mathews, 1937 – C & S North I, New Zealand.
  • Descriptive notes

    53–54 cm; male 820–1077 g, female 680–870 g. Generally slate-blue with greenish gloss on head, neck and back, chestnut spots on breast, outer secondaries... read more


    Male gives high-pitched piercing, wheezing whistles in territorial defence or advertisement, with... read more


    Mountain streams and small, narrow rivers of clear, fast-flowing waters in well-vegetated areas,... read more

    Food and feeding

    Aquatic invertebrates, mainly insect (chironoid and cased caddis fly) larvae, but extensive range recorded; also some algae and berries of... read more


    Starts mostly mid Aug with majority of first nests attempted by late Oct, with repeat laying (following early loss of first clutches)... read more


    Mainly sedentary, adult birds occurring within breeding territory (c. 0·7–1 km linear... read more

    Status and conservation

    ENDANGERED. Previously considered Near Threatened, as numbers very reduced and declining; formerly widespread, now rare or absent in majority of territory, dispersed in small... read more

    Recommended citation

    Carboneras, C. & Kirwan, G.M. (2019). Blue Duck (Hymenolaimus malacorhynchos). 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 6 December 2019).