Subspecies
Genus | Species | subspecies | Region | Range |
Anser | cygnoides | EU | e |
Genus
The waterfowl genus Anser includes all grey geese and sometimes the white geese. It belongs to the true geese and swan subfamily (Anserinae). The genus has a Holarctic distribution, with at least one species breeding in any open, wet habitats in the subarctic and cool temperate regions of the Northern Hemisphere in summer. Some also breed further south, reaching into warm temperate regions. They mostly migrate south in winter, typically to regions in the temperate zone. Numerous fossil species have been allocated to this genus. As the true geese are near-impossible to assign osteologically to genus, this must be viewed with caution. It can be assumed with limited certainty that European fossils from known inland sites belong into Anser. As species related to the Canada Goose have been described from the Late Miocene onwards in North America too, sometimes from the same localities as the presumed grey geese, it casts serious doubt on the correct generic assignment of the supposed North American fossil geese. The Early Pliocene Branta howardae is one of the cases where doubts have been expressed about its generic assignment.[citation needed] Similarly, Heterochen = Anser pratensis seems to differ profoundly from other species of Anser and might be placed into a different genus; alternatively, it might have been a unique example of a grey goose adapted for perching in trees.
Physical charateristics
Listen to the sound of Swan Goose
[audio:https://planetofbirds.com/MASTER/ANSERIFORMES/Anatidae/sounds/Swan Goose.mp3]
Copyright remark: Most sounds derived from xeno-canto
wingspan min.: | 0 | cm | wingspan max.: | 0 | cm |
size min.: | 81 | cm | size max.: | 94 | cm |
incubation min.: | 27 | days | incubation max.: | 30 | days |
fledging min.: | 75 | days | fledging max.: | 90 | days |
broods: | 1 | eggs min.: | 5 | ||
eggs max.: | 8 |
Range
Habitat
Reproduction
Feeding habits
Video Swan Goose
copyright: Josep del Hoyo
Conservation
In Russia, the main threats are uncontrolled hunting, and drainage and ploughing of breeding and moulting habitats, but disturbance by people and cattle also cause high levels of chick mortality. In China, agricultural development at breeding grounds has resulted in wetland destruction and increased disturbance. Egg collection on Sanjiang plain (China), coupled with habitat loss to agricultural development, has probably resulted in a decline in the numbers of breeding Anatidae there of 90% in the last 30 years. Recent droughts on the breeding grounds have resulted in a number of years of poor recruitment. Hunting of waterfowl remains a serious problem in many parts of China. Its wetland wintering grounds are under increasing pressure from development and pollution
