The torrent duck (''Merganetta armata'') is a member of the

duck Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form t ...

goose A goose ( : geese) is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera ''Anser'' (the grey geese and white geese) and '' Branta'' (the black geese). Some other birds, mostly related to the ...

and

swan Swans are birds of the family (biology), family Anatidae within the genus ''Cygnus''. The swans' closest relatives include the goose, geese and ducks. Swans are grouped with the closely related geese in the subfamily Anserinae where they form t ...

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Anatidae The Anatidae are the biological family of water birds that includes ducks, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted for swimming, floating ...

. It is the only member of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

''Merganetta''. It is placed in the shelduck

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Tadorninae after the " perching duck" assemblage to which it was formerly assigned was dissolved because it turned out to be

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

. This long

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

is a resident breeder in the

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

, nesting in small waterside caves and other sheltered spots. Like the blue duck, it holds territories on fast flowing mountain rivers, usually above . It is a powerful swimmer and diver even in white water, but is reluctant to fly more than short distances. It is not particularly wary when located. Male torrent ducks have a striking black and white head and neck pattern and a red bill. In flight they show dark wings with a green speculum. Females of all subspecies are somewhat smaller than the drakes; they have orange underparts and throat, with the head and upperparts grey and a yellower bill. Juveniles are pale grey above and whitish below. The male's call is a shrill whistle, while the female's is a throatier whistle. This is a declining species due to competition for its

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

food from introduced

trout Trout are species of freshwater fish belonging to the genera '' Oncorhynchus'', ''Salmo'' and ''Salvelinus'', all of the subfamily Salmoninae of the family Salmonidae. The word ''trout'' is also used as part of the name of some non-salmoni ...

, pollution, forest destruction, and damming of mountain rivers for hydroelectric schemes. The

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

an population seems to be relatively stable, while the more northern ones are more seriously affected. However, the overall population is still large enough to warrant classification as a Species of Least Concern in the IUCN Redlist.

Subspecies

The

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

taxonomy can be confusing. Males of the southern

nominate subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

''M. a. armata'', the Chilean torrent duck, have grey back and blackish underparts, with a chestnut belly. Males of the slightly smaller northern subspecies, the Colombian torrent duck, ''M. a. colombiana'', are paler underneath, with streaked grey-brown underparts. Males of a third subspecies, the Peruvian torrent duck, ''M. a. leucogenis'', are intermediate but very variable in plumage; some have entirely black underparts (''turneri''

morph Morph may refer to: Biology * Morph (zoology), a visual or behavioral difference between organisms of distinct populations in a species * Muller's morphs, a classification scheme for genetic mutations * "-morph", a suffix commonly used in tax ...

). Only males of the Chilean torrent duck have a black 'teardrop' mark beneath the eye. The Peruvian torrent duck is sometimes split into 4 subspecies (''leucogenis'', ''turneri'', ''garleppi'' and ''berlepschi''), but these are more likely simply color variations, as they are not limited to distinct areas. File:Merganetta armata - Rio Urumamba, Peru -juvenile and female-8.jpg, Juvenile (left) and female Peruvian torrent duck on the Urubamba River, Peru File:Merganetta armata - Rio Urumamba, Peru -male-8.jpg, Male Peruvian torrent duck on the rocky banks of the Urubamba River, Peru File:MerganettaTurneriSmit.jpg, Male (top) and female Peruvian torrent duck, ''turneri'' morph File:TorrentDuckM.jpg, Male Chilean torrent duck near

Fitz Roy Monte Fitz Roy (also known as Cerro Chaltén, Cerro Fitz Roy, or simply Mount Fitz Roy) is a mountain in Patagonia, on the border between Argentina and Chile.torrent duck The torrent duck (''Merganetta armata'') is a member of the duck, goose and swan family (biology), family Anatidae. It is the only member of the genus ''Merganetta''. It is placed in the shelduck subfamily Tadorninae after the "perching duck" ass ...

torrent duck The torrent duck (''Merganetta armata'') is a member of the duck, goose and swan family (biology), family Anatidae. It is the only member of the genus ''Merganetta''. It is placed in the shelduck subfamily Tadorninae after the "perching duck" ass ...

Birds of the Andes