Kingdoms / Animalia / Craniata / Aves / Anseriformes / Anatidae / Aythya / Species
< >  Aythya affinis - Lesser scaup (Click photographs/illustrations: full picture & further details)
Click Photo for full-page view Click Photo for full-page view Click Photo for full-page view

INFORMATION AVAILABLE

GENERAL & REFERENCES

EXTERNAL APPEARANCES

REPRODUCTION

BEHAVIOUR

NATURAL DIET

RANGE & HABITAT

CONSERVATION

Click image to return to Waterfowl Contents FlowchartCONTENTS
(Waterfowl)

Click image for list of Waterfowl Species

Click image for list of Waterfowl Agents
Click image for list of Waterfowl Diseases
Click image for list of Waterfowl Environmental Events / Factors

Return to top of page

General and References

Alternative Names (Synonyms)

Bluebill
Little bluebill
Broadbill
Kleine Bergente (German)
Veilchenente (German)
Petit milouinan (French)
Fuligule à tête noire (French)
Porrón bola (Spanish)
Costero chico (Spanish)

Names for newly-hatched

Duckling, downy.

Names for non-breeding males or other colour-phases

Eclipse.

Return to list of "INFORMATION AVAILABLE" for this species

References

Species Author

Debra Bourne

Major References

B1, B3, B6, B8, B19, B25, B26.

Aviculture references:
B29, B30, B31, B40, B94, B97, B128.w1
D1, D8

Other References

--
Click image for main Reference Section

Return to top of page

TAXA Group (where information has been collated for an entire group on a modular basis)

Parent Group

Specific Needs Group referenced in Management Techniques

Return to top of page

Aviculture Information

Notes

General information:
  • Pochards are diving ducks which spend most of their time on water, and are ungainly on land. They are generally hardy, sociable and easy to maintain in captivity. They should be kept with deep water available for diving, three to seven feet suggested (B29), or at least half the area 60cm and preferably one metre deep (D1), with shallow sloping banks for easy exit from the water, also islands, good marginal vegetation and loafing areas. Water providing a good supply of natural animal and vegetable food is preferred.
  • These ducks may be kept in mixed collections with dabbling ducks, including smaller species such as teal. They should be fed wheat in water, encouraging their natural diving behaviour. Pellets should also be fed. They may breed better if a group rather than single pair kept, as this allows their normal group displaying activity.
  • 12x12x14 inch (30x30x35cm) nest box with 5 inch (12.5cm) entrance hole suggested, placed under cover at the edge of the pond (B128.w1).

(B29, B40, B94, B128.w1, D1)

Species-specific information:

  • Lesser scaup are easy to manage; breeding is most likely on large lakes.
  • These ducks are fairly easy to breed. Nests are well concealed in vegetation on islets (preferred) or shores, eggs usually laid in June (rarely May) (B31); April to May (B29). Hand-rearing under heat lamp suggested.
  • Hybridise easily with other Aythya spp., particularly Aythya marila - Greater scaup with which fertile hybrids are produced.

(B29, B30, B31, B94, B97).

Aviornis UK Ringing Scheme suggested average closed ring size: J 9.0mm (D8).

Management Techniques

--
Click image for main Aviculture Section

Return to top of page

External Appearance (Morphology)

Measurement & Weight

Length 15-19 inches, 38-48cm (B3, B1)
Adult weight General About 800-850g (B1).
Male Average 850g, maximum 1087g (B3); mean 1.9 lbs. (B8).
Female Average 800g, maximum 951g (B3); mean 1.7 lbs. (B8).
Newly-hatched weight --
Growth rate --

Return to top of page

Head

Adult Bill Male Blue-grey with black nail (B3, B6, B25, B26).
Variations (If present) Female: Dark blue-grey with black nail (B3, B6, B25).
Eyes (Iris) Male Yellow/orange (B3, B6, B25).
Variations(If present) Female: yellow-brown (B3, B6, B25).
Juvenile Bill Dark blue-grey with black nail (B3, B6, B25).
Eyes (Iris) Yellow/brown (B3, B6, B25).

Return to top of page

Legs

Adult Male Greenish/bluish grey (B3, B6, B25).
Variations (If present) Female: darker grey (B3, B6, B25).
Juvenile Grey (B3, B6, B25).

Return to top of page

Plumage

Adult Male Head (with slight crest), neck and breast glossy purple-black, tail, rump and tailcoverts black, flanks and abdomen white, with some grey vermiculations hind part of flanks, upperparts grey vermiculated with black (darker than Greater Scaup). Wing coverts grey vermiculated with black, secondaries white with black tips, primaries dusky (B3, B6, B25, B26).
Variations (If present) Female:- head and neck dark brown with white patch around bill; breast and upperparts brown, flanks mottled grey-brown, abdomen whitish. Wing as male but coverts brown (B3, B6, B25, B26).

Eclipse:- brown-black rather than glossy black, brown colouring over paler areas (B3, B6, B25).

Juvenile Similar to female but duller, more uniform brown; no/little white on face (B3, B6, B25).

Return to top of page

Newly-hatched Characteristics

General: Upperparts dark brown/blackish with indistinct pale patches wing and rump; underparts including face buff-yellow, dark streak through eye, second lower streak (B1, B6).
Bill: Grey (B6).
Feet: Grey (B6).

Return to top of page

Reproduction

Reproductive Season

Time of year Begins May to June (B1, B26).
No. of Clutches Re-nest, sometimes repeatedly, if clutch lost (B3).

Return to top of page

Nest placement and structure

On the ground in thick vegetation near water, sometimes on islands or floating sedge mats, a shallow depression with plant material and down (B1, B3, B6, B25, B26).

Return to top of page

Egg clutches

No. of Eggs Average --
Range 8-10 (B8); 9-15 (B6); 9-11, up to 25 with dump-nesting (B1).
Egg Description Stone or buff-grey to dark olive-buff (B3, B6, B8, B26); size: 56x40mm; weight: 44g (B3).

Return to top of page

Incubation

24-28 days (B8); 23-26 days (B6); 21-22 days (B1); 23-25 days (B3).

Return to top of page

Hatching

Synchronous.

Return to top of page

Fledging

45-50 days (B1, B3, B8).

Return to top of page

Sexual Maturity

Males One to two years old (B1).
Females One to two years old (B1).

Return to top of page

Behaviour

Feeding Behaviour

Adults Dive in shallow water, sieve through bottom mud (B1, B3).
Newly-hatched --

Return to top of page

Parental Behaviour

Nest-building Solitary or in loose colonies; nest built by female (B1, B8, B26).
Incubation By female, with male usually leaving early in incubation or by halfway through incubation (B3, B25, B26).
Newly-hatched Tended by female (B3).
Juveniles

Often deserted by female before fledging; broods frequently merge (B3, B8).

Return to top of page

Social Behaviour

Intra-specific Sociable, often in 'rafts' of many thousands of birds in autumn and winter; share home-ranges on breeding grounds (B3, B25).
Inter-specific Sometimes nest with tern or gull colonies (B3, B8, B25).

Return to top of page

Sexual Behaviour

Pair-forming begins in winter. Male leaves female early in incubation, certainly by half way through incubation (B3, B8, B25).

Return to top of page

Predation in Wild

--

Return to top of page

Activity Patterns

Found in rafts on open water, away from shoreline, resting during the day (B6, B26).
Circadian Feeding peaks in early morning on non-tidal waters; feed close to shore at high tide (B26).

Return to top of page

Natural Diet

Adults

Mixed diet: aquatic invertebrates (insects, molluscs), fish; seeds, root, green parts of aquatic plants (B1, B3, B6, B26).

Return to top of page

Newly-hatched

--

Return to top of page

Range and Habitat

Distribution and Movement (Migration etc.)

Normal

North America, from Alaska south to north-western USA and east to the Great Lakes area (B1, B19).

Migrates to coastal (Atlantic and Pacific) plains of USA, Mississippi valley, Central America and southward to northern Columbia, West Indies, Bermuda, Hawaii (B1, B19).

Occasional and Accidental

Vagrant: Ecuador, Surinam , Venezuela, Trinidad in south, Greenland in North (B1, B25).

Very occasionally may reach Britain (B1).

Introduced

--

Return to top of page

Habitat

Breeding: inland freshwater lakes (moderate depth), ponds, marshes, river deltas, in open/lightly wooded areas. Winter on larger lakes and brackish lagoons, also estuaries, coastal marshes (fresh and brackish rather than salt water) (B1, B3, B19, B25, B26).

Return to top of page

Conservation

Intraspecific variation

--

Return to top of page

Conservation Status

Wild Population -
(Importance)

Not globally threatened: common, abundant (number in millions)(B1, B8).

CITES listing --
Red-data book listing --
Threats --

Return to top of page

Captive Populations

Common and frequently bred in collections (B8).

Return to top of page

Trade

--

Return to top of page