Hardhead

For other uses, see Hardhead (disambiguation).
Hardhead
Female
Male
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Subfamily: Aythyinae
Genus: Aythya
Species: A. australis
Binomial name
Aythya australis
(Eyton, 1838)
Subspecies
  • A. a. extima (Mayr, 1940) (disputed)
  • A. a. australis (Eyton, 1838)
Synonyms

Nyroca australis Eyton, 1838

The hardhead (Aythya australis) (also white-eyed duck) is the only true diving duck found in Australia. Hardheads are common in the south-east of Australia, particularly in the Murray-Darling Basin, but also in the wetter country near the coasts. They are moderately nomadic in normal years, but disperse widely in times of drought. Significant numbers reach as far afield as New Guinea, New Zealand, and the islands of the Pacific, where they can remain for some time, even breeding for a season or two.

Like the other members of the pochard group, hardheads feed by diving deeply, often staying submerged for as long as a minute at a time. They slip under the water with barely a ripple, simply lowering their heads and thrusting with their powerful webbed feet. They eat a broad range of small aquatic creatures, and supplement this with water weeds.

Hardheads prefer larger lakes, swamps and rivers with deep, still water, but are often seen in smaller streams, flooded grasslands, and shallow pools. As a general rule, they avoid coastal waters. They rarely come to land and never perch in trees.

Hardheads are small by duck standards, usually not much more than 45 cm long but reaching 60 cm sometimes, and noticeably more rounded in overall form than most ducks. Both male and female are a fairly uniform chocolate-brown above, with rufous flanks and white undersides (which are often not visible if the duck is in the water). The trailing edges and almost the entire underside of the wings are white. In the male, the eyes are a striking white, in the female, brown.

Widespread throughout its large range, the hardhead is evaluated as Least Concern on the IUCN Red List of Threatened Species.[1]

Standing

References

External links

Wikispecies has information related to: Aythya australis
This article is issued from Wikipedia - version of the Friday, May 23, 2014. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.