Hardhead

Hardhead

:"For the fictional characters in the Transformers series see Hardhead (Transformers).":"For the freshwater fishes, see "Mylopharodon". For the marine fishes, see Sciaenidae.Taxobox
name = Hardhead
status = LC | status_system = IUCN3.1


regnum = Animalia
phylum = Chordata
classis = Aves
ordo = Anseriformes
familia = Anatidae
genus = "Aythya"
species = "A. australis"
binomial = "Aythya australis"
binomial_authority = Eyton, 1838
The Hardhead, "Aytha australis" 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 (Hardheads sometimes used to be known as "White-eyed Ducks"), in the female, brown.

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

References

* Database entry includes justification for why this species is of least concern

External links

* [http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=479&m=0 BirdLife Species Factsheet]
* [http://www.redlist.org/search/details.php?species=47219 IUCN Red List]


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  • Hardhead — Hard head ( h[e^]d ), n. 1. Clash or collision of heads in contest. Dryden. [1913 Webster] 2. (Zo[ o]l.) (a) The menhaden. See {Menhaden}. [Local, U. S.] (b) Block s gurnard ({Trigla gurnardus}) of Europe. (c) A California salmon; the steelhead.… …   The Collaborative International Dictionary of English

  • hardhead — [härd′hed΄] n. 1. a shrewd person, not easily moved 2. any of various fishes; esp., a slender river minnow (Mylopharodon conocephalus) of central and N California …   English World dictionary

  • hardhead — ˈ ̷ ̷ˌ ̷ ̷ noun 1. a. : a shrewd practical hardheaded person a prospect that moves hardheads as well as visionaries b. : blockhead 2. a …   Useful english dictionary

  • hardhead — Gray Gray (gr[=a]), a. [Compar. {Grayer}; superl. {Grayest}.] [OE. gray, grey, AS. gr[=ae]g, gr[=e]g; akin to D. graauw, OHG. gr[=a]o, G. grau, Dan. graa, Sw. gr[*a], Icel. gr[=a]r.] [Written also {grey}.] 1. any color of neutral hue between… …   The Collaborative International Dictionary of English

  • hardhead — Gray whale Gray whale (Zo[ o]l.), a rather large and swift baleen whale of the northern Pacific ({Eschrichtius robustus}, formerly {Rhachianectes glaucus}), having short jaws and no dorsal fin; called also {grayback}, {devilfish}, and {hardhead} …   The Collaborative International Dictionary of English

  • hardhead — Steelhead Steel head ( h[e^]d ), n. 1. (Zo[ o]l.) A North Pacific salmon ({Salmo Gairdneri}) found from Northern California to Siberia; called also {hardhead}, and {preestl}. [1913 Webster] 2. (Zo[ o]l.) The ruddy duck. [1913 Webster] …   The Collaborative International Dictionary of English

  • hardhead — menhaden men*ha den, n. (Zo[ o]l.) An American marine fish ({Brevoortia tyrannus}) of the Herring family ({Clupeidae}), chiefly valuable for its oil and as a component of fertilizers; called also {mossbunker}, {bony fish}, {chebog}, {pogy},… …   The Collaborative International Dictionary of English

  • hardhead — Ruddy Rud dy, a. [Compar. {Ruddier}; superl. {Ruddiest}.] [AS. rudig. See {Rud}, n.] 1. Of a red color; red, or reddish; as, a ruddy sky; a ruddy flame. Milton. [1913 Webster] They were more ruddy in body than rubies. Lam. iv. 7. [1913 Webster] 2 …   The Collaborative International Dictionary of English

  • hardhead — noun Date: 15th century 1. a. a hardheaded person b. blockhead 2. plural hardheads also hardhead any of several fishes especially with a spiny or bony head; especially Atlantic croaker …   New Collegiate Dictionary

  • hardhead — hardhead1 /hahrd hed /, n. 1. a shrewd, practical person. 2. a blockhead. 3. a freshwater fish, Mylopharodon conocephalus, of California. 4. the Atlantic croaker. See under croaker (def. 2). 5. See hardhead sponge …   Universalium

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