Kingdoms / Animalia / Craniata / Aves / Anseriformes / Anatidae / Merganetta / Species
< >  Merganetta armata - Torrent duck (Click photographs/illustrations: full picture & further details)
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INFORMATION AVAILABLE

GENERAL & REFERENCES

EXTERNAL APPEARANCES

REPRODUCTION

BEHAVIOUR

NATURAL DIET

RANGE & HABITAT

CONSERVATION

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General and References

Alternative Names (Synonyms)

Sturzbachente (German)
Merganette des torrents (French)
Canard de torrents (French)
Pato torrentero (Spanish)
Pato corta-corrientes (Spanish)
Argentine torrent duck M. a. armata
Chilean torrent duck M. a. armata
Columbian torrent duck M. a. columbiana
Peruvian torrent duck M. a. leucogenis (M. a. turneri M. a. garleppi, M. a. berlepshu)

Names for newly-hatched

Duckling, downy.

Names for non-breeding males or other colour-phases

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References

Species Author

Debra Bourne

Major References

B1, B3, B5, B8, B19, B25, B44.9.w1

Aviculture references:

Other References

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

Parent Group

Specific Needs Group referenced in Management Techniques

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Aviculture Information

Notes

Torrent ducks have been maintained only rarely in captivity, therefore the following avicultural information is derived from the keeping of only a few birds in one collection.

Torrent ducks may be maintained full-winged in an aviary with clear running water and rock formations and fed on standard waterfowl pellets, which may be supplemented with mealworms. They do not need to be fed in water. They will use boxes for roosting in cold weather and also while moulting.

These ducks do not appear to be aggressive to other species, but can be very aggressive to one another. It is suggested that intended pairs should be kept together from the time the young birds are developing their first feathers. Even birds maintained together in this way may become aggressive at a later stage: either male or female may become aggressive to their mate and birds may be lost due to this aggression. Forming pairs between adult birds is very difficult and great caution is required. A new bird introduced to replace a mate is likely to be attacked. If new pair formation is necessary the birds should be introduced in a new enclosure (not home territory to either bird), and kept separated by wire initially, only being put together when their behaviour indicates good pair formation. However, aggression may occur even in apparently compatible pairs.

Nest boxes should be provided built into or on rock formations. 

Artificial rearing of ducklings is not difficult. Ducklings have very advanced development when hatched. They are very active and good jumpers and may jump vertically perhaps 18 inches (45cm): an extra deep brooder box is required and a wire cover should be used. They may be reared in groups and have been reared successfully off water, although is is possible that rearing on water might be preferable. Ducklings may be reared on standard starter or chick crumbs fed dry; they tend to take these from around the outside of the food bowl. Bacterial enteritis has been reported in juveniles when bad weather forced a delay in getting the ducklings outside.

(V.w9)

Management Techniques

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External Appearance (Morphology)

Measurement & Weight

Length 17-18 inches, 43-46cm (B3, B1)
Adult weight General 315-440g (B1)
Male About 440g (B3); mean 15.5 ounces (B8).
Female 315-400g (B3); mean 11.6 ounces (B8).
Newly-hatched weight --
Growth rate --

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Head

Adult Bill Male Bright cherry red with pale yellowish nail (B3, B250
Variations (If present) --
Eyes (Iris) Male Dark brown (B3, B25)
Variations(If present) --
Juvenile Bill Grey-red (B25)
Eyes (Iris) Dark brown (B25)

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Legs

Adult Male Orange-red with grey webs (B3, B25)
Variations (If present) --
Juvenile Grey-red (B25)

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Plumage

Adult Male N.B. Variable within each subspecies. Head and neck white, black crown and continuing down hindneck, black line through eye and continuing down neck with second line splitting off across nape to hindneck. Mantle and scapular feathers pointed, elongated, black with white or brown edges. Wings: upperwing coverts blue-grey, secondaries iridescent green, bordered white in front and behind, primaries brown. Tail: grey brown, feathers stiff and splayed out, uppertail coverts finely vermiculated grey and black, undertail coverts vary from grey to (armata, turneri) black.
(B3, B5, B8, B25)
Variations (If present) Female:- upperparts grey, crown of head and back of neck finely vermiculated with black, scapulars elongated, pointed, with black centres; underparts including face, throat and foreneck reddish, wings as male.

Subspecies variations:- M. a. armata black ‘tear’ down from eye to join black throat and sometimes dorsally from eye to crown. M a. armata: breast and underside black, flanks brown with black streaks, elongated mantle and scapular feathers white with black centres; M. a. columbiana breast, flanks and underparts pale grey striped with black, elongated scapulars brown with black centres; M. a. leucogenis varying from brown-and-black scapulars, white-and black underparts (leucogenis) to pale brown-and-black scapulars and underparts (garleppi), white-and-black scapulars, brown-and-black underparts (berlepschi) to brown-and black scapulars, blackish underparts (turneri).
(B1, B3, B5, B8, B25)

Juvenile Similar to female but duller; upperparts grey-brown, underparts whitish, flanks and sides of breast barred with black. (B1, B3,B25)

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Newly-hatched Characteristics

General: Upperparts black with white strip along body; underparts including face white, with black strip back from eye. (B5, B8)
Bill: Black (B5, B8)
Feet: Orange (B5)

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Reproduction

Reproductive Season

Time of year Geographic variation. Begin February in Columbia.
No. of Clutches May re-nest if nest flooded (B8).

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Nest placement and structure

In hollows and cavities among rocks or roots, on rocky ledges or occasionally on the ground in thick vegetation, nest of dry grass lined with down and some feathers (B1, B8, B25)

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Egg clutches

No. of Eggs Average --
Range 3-4 (B1, B8), possibly 5 (B8)
Egg Description Creamy-tan or dull buff (B8); size: 61x41mm, weight: 65g (B3)

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Incubation

43-44 days (B1, B8)

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Hatching

Synchronous

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Fledging

Possibly 120 days (B8).

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Sexual Maturity

Males --
Females --

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Behaviour

Feeding Behaviour

Adults Dive, but also head-dip and upend, probing among rocks.
Newly-hatched --

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Parental Behaviour

Nest-building --
Incubation By female (B3, B8)
Newly-hatched tended by both parents (B3, B8)
Juveniles

Wander to find their own territory (B8).

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Social Behaviour

Intra-specific Territorial year-round. Usually seen as pairs or family groups. (B3, B8)
Inter-specific --

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Sexual Behaviour

Monogamous, strong permanent pair-bonds (B3, B8).

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Predation in Wild

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Activity Patterns

More considerable distances downstream in the water, returning upstream by swimming close to banks or by flying (B8). Roost in traditional roosting holes (V.w9).
Circadian --

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Natural Diet

Adults

Caddisfly (Caddis spp.) larvae, also stonefly (Rheophila) and mayfly larvae, molluscs and occasional small fish (B1, B3, B8).

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Newly-hatched

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Range and Habitat

Distribution and Movement (Migration etc.)

Normal M. a. columbiana Andes from Colombia and northwestern Venezuela to northern and central Ecuador
M. a leucogenis Andes from central Ecuador to central Peru
M. a. turneri Andes of southern Peru
M. a. garleppi Andes of Bolivia
M. a. berlepshi, Andes of northern Chile and north-western Australia
(M. a. leucogenis including garleppi, turneri and berlepshi: west-central South America, Andes of Peru, western and central Bolivia, north-western Argentina)
M. a. armata Andes of Chili and Argentina, south to Tierra del Fuego.
(B1, B19)

Sedentary once territory established (B1, B8).

Occasional and Accidental

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Introduced

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Habitat

Fast-flowing mountain streams and rivers with rapids and waterfalls but also calmer areas. (B1, B3, B8, B19, B25)

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Conservation

Intraspecific variation

Between three and six subspecies recognised, with leucogenis sometimes considered to include turneri, garleppi and berlepschi. Plumage of males varies between and within subspecies.
M. a. columbiana Andes from Venezuela to northern Ecuador
M. a leucogenis Andes from central Ecuador to central Peru
M. a. turneri Andes of southern Peru
M. a. garleppi Andes of Bolivia
M. a. berlepshi, Andes of northern Chile and north-western Australia
M. a. armata Andes of Chili and Argentina
(B1)

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Conservation Status

Wild Population -
(Importance)

Decreasing population (B1, B8, B25)

Merganetta armata leucogenus - Peruvian torrent duck, and Merganetta armata colombiana - Columbian torrent duck aare considered Vulnerable (B44.9.w1)

CITES listing --
Red-data book listing --
Threats Habitat loss from dams, pollution, competition for food with introduced trout (B1, B8, B25)

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Captive Populations

Extremely rarely found in collections (B8).

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Trade

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