Hardhead

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.

For other uses, see Hardhead (disambiguation).

Hardhead
Female
Male

Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
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

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.

Calls

Usually silent, but males have a soft, wheezy whistle and 'whirr'. females have a loud rattling 'gaark' call.[2]

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

Standing
gollark: * any asymmetric crypto
gollark: OH RIGHT.
gollark: FIX THE SEWAGE OUTFLOW YOU POTATO
gollark: This has been today's daily reminder that self-control is an illusion and we are all shaped by vast cosmic forces we will never be able to comprehend
gollark: I mean, if you want 64GB later, might be best to buy 32GB as 16x2, actually...

References
  1. BirdLife International (2012). "Aythya australis". IUCN Red List of Threatened Species. 2012. Retrieved 26 November 2013.CS1 maint: ref=harv (link)
  2. BIRDS IN BACKYARDS Hardhead Scientific Name: Aythya australis Featured bird groups: Water birds Atlas Number: 215
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.