| Kingdoms / Animalia / Craniata / Aves / Anseriformes / Anatidae / Aythya / Species |
| < > Aythya australis - Hardhead (Click photographs/illustrations: full picture & further details) |
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Alternative Names (Synonyms) |
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| Australian hardhead Australian pochard Australian white-eye Australasian white-eye White-eye White-eyed duck Brownhead Copperhead Tasmanmoorente (German) Australische Moorente (German) Fuligule austral (French) Milouin dAustralie (French) Porrón Australiano (Spanish) Pato ojos blancos de Australia (Spanish) Aythya australis australis - Australian white-eye Aythya australis extima - Banks Island white-eye |
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Names for newly-hatched |
Duckling, downy. |
Names for non-breeding males or other colour-phases |
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Species Author |
Debra Bourne |
Major References |
B1, B3, B6, B7, B8, B19, B25, B26. Aviculture references: |
Other References |
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TAXA Group (where information has been collated for an entire group on a modular basis) |
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Parent Group |
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Specific Needs Group referenced in Management Techniques |
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Aviculture Information |
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Notes |
General information:
Species-specific information:
Aviornis UK Ringing Scheme suggested average closed ring size: L 11.0mm (D8). |
Management Techniques |
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External Appearance (Morphology)
Measurement & Weight |
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| Length | 18 inches, 46cm (B3); 46-49cm (B1). | |
| Adult weight | General | 525-1100g (B1). |
| Male | 525-1100g average 902g (B3); A. a. australis mean 2.0 lbs. (B8). | |
| Female | 530-1060g average 838g (B3); A. a. australis mean 1.8 lbs. (B8). | |
| Newly-hatched weight | -- | |
| Growth rate | -- | |
| Adult | Bill | Male | Grey with wide, grey-blue subterminal band, black nail (B6, B26) |
| Variations (If present) | Grey with narrow whitish subterminal band (B26) | ||
| Eyes (Iris) | Male | -- | |
| Variations(If present) | -- | ||
| Juvenile | Bill | Grey with narrow whitish subterminal band (B26) | |
| Eyes (Iris) | Brown (B6). | ||
| Adult | Male | Grey (B6). |
| Variations (If present) | -- | |
| Juvenile | Grey (B6). | |
| Adult | Male | Head, neck, body generally dark chestnut brown, upperparts darker, flanks feathers faintly buff-edged, abdomen usually whitish, sometimes mottled brown, undertail coverts white. Wing coverts dark reddish-brown, primaries and secondaries mostly white with brown tips and brown outer primaries (B3, B6, B8, B25, B26). |
| Variations (If present) | Female:-
paler, browner, duller, throat pale/mottled (B1, B3, B6, B25, B26). Aythya australis extima:- head and throat may be more black-brown (B8). |
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| Juvenile | Similar to female; paler, browner, duller; abdomen mottled with brown (B1, B3, B6, B25, B26). | |
Newly-hatched Characteristics |
| General: Upperparts
brown with yellowish markings on wings, sides and back, underparts and face yellowish
(B1, B6, B7). Bill: Grey (B6, B7). Feet: Grey (B6, B7). |
Reproductive Season |
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| Time of year | Variable and irregular: when water levels highest (B1, B6, B8). October to November in south-western Australia, September to December, New South Wales, April and May Northern Australia (B3). |
| No. of Clutches | -- |
Nest placement and structure |
| In reeds near or over water, a platform woven from reeds, sedges, other vegetation, some downy lining (B1, B3, B6, B8, B26). |
Egg clutches |
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| No. of Eggs | Average | 9-12 (B3); 9-13 (B8). |
| Range | 6-18 (B8). | |
| Egg Description | Cream-white (B3, B8); size: 54x42mm; weight: 60g (B3). | |
| 25 days (B1, B3, B8). |
| Synchronous. |
| 50-65 days (B8). |
Sexual Maturity |
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| Males | -- |
| Females | -- |
Feeding Behaviour |
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| Adults | Dive, head-dip, up-end and dabble (B1, B3, B8, B25, B26). |
| Newly-hatched | -- |
Parental Behaviour |
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| Nest-building | -- |
| Incubation | By female (B3). |
| Newly-hatched | Tended by female (B3). |
| Juveniles | -- |
Social Behaviour |
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| Intra-specific | Sociable, found in small groups or larger flocks (thousands) (B8, B25). |
| Inter-specific | Sometimes feed with Anas superciliosa - Pacific black ducks, Cygnus atratus - black swans, Australian pelicans (B8). |
Sexual Behaviour |
| Pairs form rapidly when rising water triggers breeding (B8, B25) |
Predation in Wild |
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| Loaf on banks and may sometimes roost on banks, stumps, low branches (B8). | |
| Circadian | -- |
| Mainly vegetarian: seeds, flowers, green parts grasses, sedges, aquatic plants; also (up to 10% of diet) aquatic invertebrates (insects and their larvae, mussels, crustaceans) and small fish (B1, B3, B26). |
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Distribution and Movement (Migration etc.) |
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| Normal | South-western and eastern Australia locally in New Guinea, isolated population in New Hebrides (Banks Island), probably also Vanuatu and New Caledonia. Wanders in dry season, particularly in droughts: all over Australia, Tasmania, reaching New Zealand, Auckland Islands, Java, Sulawesi, New Guinea, New Caladonia (B1, B19). |
| Occasional and Accidental | -- |
| Introduced | -- |
| Swamps, marshes, deep permanent lakes and ponds with abundant emergent vegetation (B1, B8, B19). |
Intraspecific variation |
| Aythya australis australis -
Australian white-eye Aythya australis extima - Banks Island white-eye |
Conservation Status |
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| Wild Population - (Importance) |
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| CITES listing | -- |
| Red-data book listing | -- |
| Threats | Habitat loss (drainage of marshes and swamps) (B1, B8, B25, B26). |
Captive Populations |
| Maintained for generations in captivity (B8); relatively popular in Australian collections B139. |
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