Bird Families

River ducks


River ducks, or noble ducks (lat. Anas), is a genus of birds of the duck family. Includes birds such as mallards, wiggles, pintails, teals, broad-nosed birds and other birds, divided into separate categories - subgenera. Some birdwatchers have suggested raising the status of these subgenera to separate genera.

Small representatives of this group are called teals, otherwise they are medium-sized ducks. Drakes of most species show vivid details of the breeding outfit - in particular, in the form of a “mirror” on the secondary flight feathers. They inhabit muddy shoals, shallow areas of freshwater reservoirs; outside the breeding season, they sometimes settle in coastal marshes. They feed on phyto- and zooplankton, algae, small invertebrates, which are harvested in the upper layer of water and filtered using a superbly developed system consisting of a wide beak with current plates along the edges, and a fleshy rough tongue - the so-called filtering apparatus. Sometimes they dive for food, immersing the front part of the body in water, but not as willingly as diving ducks.


The phylogenetic position of species from this genus is considered one of the most controversial among all modern groups of birds. One of the obstacles preventing ornithologists from compiling a complete picture of the evolutionary development of river ducks is the fact that the divergence of the two main groups of the genus - mallards and teals - occurred relatively recently (approximately in the second half of the Pleistocene) and in a very short period of time. In addition, it is likely that frequent hybridization between these birds, especially within subgenera, played an important role in the evolution of river ducks. Molecular studies by analyzing mtDNA sequences create additional confusion, showing dubious results for relationships between species.

However, there are some major treasures that can be identified. For example, this is the classic subgenus uniting mallard duck Anas is a monophyletic (in a broad sense, not holophyletic) group, which does not raise questions among modern taxonomists. On the other hand, the phylogenetics of teals looks very confusing.

At the present time, it is more or less becoming obvious that the wiggles have a more distant relationship to other real ducks than the mallards, and should be brought into a separate genus. The same applies to the kloktun, to the teal-cracker, to the "black-capped" group Punanetta, and shirokoskam and other birds with blue wings. Witches in relation to other species have common morphological and behavioral characteristics, however, the difference in their mtDNA of two mitochondrial protein-coding genes - cytochromes b (cytb) and the 2nd subunit of nicotinamide dehydrogenase (ND2) also suggests that their status should be increased to a separate genus Mareca (also including the gray duck and killer whale).

The proposed list is suggested based on morphological, molecular and behavioral characteristics.

  • Possible genus Mareca
    • Sviyaz (Anas penelope)
    • † Amsterdam Flightless Witch (Anas marecula)
    • American Wig (Anas americana)
    • Sumptuous Wiggle (Anas sibilatrix)
  • Subgenus Chaulelasmus
    • Gray duck (Anas strepera)
      • Anas strepera couesi - became extinct in the second half of the 19th century
  • Subgenus Eunetta
    • Killer whale (Anas falcata)
  • Subgenus Dafila
    • Pintail (Anas acuta)
    • Kerguelen pintail (Anas eatoni)
      • Anas eatoni eatoni
      • Anas eatoni drygalskii
    • Yellow-billed pintail (Anas georgica)
      • Anas georgica georgica
      • Anas georgica niceforoi - became extinct in the 1950s
    • Barnacle pintail (Anas bahamensis) (formerly Poecilonetta)
    • Red-billed pintail (Anas erythrorhyncha) (formerly Poecilonetta)
    • Cape teal (Anas capensis) (formerly Nettion)
  • Subgenus Nettion
    • Indian Ocean hoard
      • Madagascar teal (Anas bernieri)
      • † Mauritian duck (Anas theodori)
      • Gray teal (Anas gibberifrons)
        • Anas gibberifrons remissa - extinct (circa 1959)
      • Anas gracilis (previously as part of Anas gibberifrons)
      • Chestnut Teal (Anas castanea)
    • Green-winged treasure
      • Teal Whistle (Anas crecca)
      • Green-winged teal (Anas carolinensis) (previously included in Anas crecca)
      • Yellow-billed Teal (Anas flavirostris)
        • Andean teal (Anas (flavirostris) andinum)
    • New Zealand treasure
      • Auckland teal (Anas aucklandica)
      • Brown teal (Anas chlorotis) (previously included in Anas aucklandica)
      • † Teal of the McCurry Islands (Anas cf. chlorotis) - fossil species
      • Campbell Teal (Anas nesiotis) (previously included in Anas aucklandica)
  • Subgenus Melananas
    • African Black Duck (Anas sparsa)
  • Subgenus Anas
    • African species ("Afranas»)
      • Madagascar Mallard (Anas melleri)
      • Yellow-nosed mallard (Anas undulata)
    • American hoard
      • Ocellated mallard (Anas fulvigula) (sometimes as part of Anas platyrhynchos)
        • Anas fulvigula fulvigula (sometimes as part of Anas platyrhynchos)
      • American Black Duck (Anas rubripes) (sometimes as part of Anas platyrhynchos)
      • Mexican mallard (Anas diazi) (sometimes as part of Anas platyrhynchos)
    • Pacific treasure
      • † Mariana Mallard (Anas (platyrhynchos) oustaleti) (sometimes seen as a subspecies Anas superciliosa)
      • Hawaiian mallard (Anas wyvilliana) (sometimes as part of Anas platyrhynchos)
      • Philippine mallard (Anas luzonica)
      • Laysan mallard (Anas laysanensis) (sometimes as part of Anas platyrhynchos)
        • † Lisyanskaya mallard (Anas cf. laysanensis) - hypothesis, has died out since 1845.
      • Gray mallard (Anas superciliosa)
    • Unclear status
      • Mallard (Anas platyrhynchos)
      • Spotted mallard (Anas poecilorhyncha)
      • Anas (poecilorhyncha) zonorhyncha - sometimes viewed as a subspecies Anas superciliosa

Species previously considered as part of the genus Anas

  • Bronze-winged duck (Speculanas specularis)
  • Kloktun (Sibirionetta formosa)
  • Striped duck (Salvadorina waigiuensis)
  • Crested duck (Lophonetta specularioides)
  • Genus Spatula
    • Australian broad-bearer (Spatula rhynchotis)
    • African shirokosnoska (Spatula smithii)
    • Blue-winged teal (Spatula discors)
    • Brown teal (Spatula cyanoptera)
    • Spotted teal (Spatula hottentota)
    • Multicolored teal (Spatula versicolor)
    • Teal pune (Spatula puna)
    • Teal cracker (Spatula querquedula)
    • Wide-nose (Spatula clypeata)
    • South American broadtail (Spatula platalea)