Taiga Bean Goose (Anser fabalis fabalis)

Taiga Bean Goose

[order] ANSERIFORMES | [family] Anatidae | [latin] Anser fabalis fabalis | [authority] Latham, 1787 | [UK] Taiga Bean Goose | [FR] Oie des moissons | [DE] Saatgans | [ES] Ansar Campestre | [NL] Rietgans

Subspecies

Monotypic species

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

Averaging only slightly smaller than Greylag Goose but not so bulky, with less weight in the rear half of body. Large, tall, rather long-billed and long-necked, essentially brown goose, with very dark head and neck obvious in flight.
At long range and in poor light, difficult to separate from other grey geese but noticeable length of dark head and neck, upright stance, and uniform upperwing in flight, characteristic. High head carriage, bulk, uniform dark plumage tone, lack of forewing contrast, rather long, deep orange-marked bill, and orange legs all diagnostic at closer ranges. Confusion with large, dark individuals of Pink-footed Goose possible, but Bean Goose never shows grey upperparts and differences in bare-part colours afford certain distinction of typical birds.

Listen to the sound of Taiga Bean Goose

[audio:http://www.planetofbirds.com/MASTER/ANSERIFORMES/Anatidae/sounds/Taiga Bean Goose.mp3]

Copyright remark: Most sounds derived from xeno-canto


wingspan min.: 140 cm wingspan max.: 174 cm
size min.: 69 cm size max.: 88 cm
incubation min.: 27 days incubation max.: 29 days
fledging min.: 38 days fledging max.: 29 days
broods: 1   eggs min.: 4  
      eggs max.: 6  

Range

Eurasia : North

Habitat

Nesting habitat includes the taiga and tundra zone, in particular the scrub ecotone. In Scandinavia, the geese nest inland at relatively high altitudes, up to 700 m. In winter, the geese traditionally occurred in the steppe zone/semi-arid zone, foraging on short grassy, so-called sodic-pasture, vegetation . In Hungary, Lesser White-fronted Geese feed predominantly in this habitat, using other types only when there is no steppe available. It was observed that the species uses pioneer vegetation at the bottom of recently-drained fishponds in the Hortobagy. Because of lack of recent knowledge about winter occurrence, present habitat usage is poorly known.

Reproduction

Nests in low hummocks and banks free from snow and post-thaw flooding. often at base of tree or among bushes. Usually close to water but could be up to 1 km away. Normally well dispersed, though sometimes forming loose colonies. Previous year’s nests re-used with new lining. The nest consists of low mound of grasses, dead leaves, moss, and other vegetation, with shallow cup lined with down, particularly after laying. Building: mostly by female, though male may help, using material within reach of nest. The clutch size is 4-6, sometimes 3 or up to 8, in one brood per season. Eggs probably laid at 24-hour intervals. after hatching the eggshells left in nest.

Incubation continues for 27-29 days and is performed by females and starts after the lat egg is laid. She covers eggs with down when she is leaving the nest. The young are hatching synchronous. The young are immediately Self-feeding. Both parents care for young in defending them against predators. When still very young the chickens are brooded by female at night.

The young fledge in about 40 days. Young remain with parents during the first autumn and winter, migrating with them in spring but will be independent before they return back to breeding grounds. Age of first breeding normally 3 years.

Feeding habits

Grasses, cereal grains, and other agricultural crops; mainly by grazing on arable and pastureland in winter. On breeding grounds, feeds on green parts of plants, flowers and fruits, seeds, and rootstocks.

Video Taiga Bean Goose

httpv://www.youtube.com/watch?v=oZE6QoA9H0s

copyright: Neon Rosell


Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
This goose inhabits tundra or taiga in northern Eurasia. The birds visiting the European Union belong to two clearly distinct populationspossibly valid species. The birds of the race fabalis are breeding in the taiga, from Sweden to the Urals, and winter mainly in Denmark and the Netherlands. A few hundreds of individuals reach England. This population is currently estimated at 80000 individuals, and seems to be increasing but decreasing following Huyskens (pers. comm.). The second population comprises the birds of the race rossicus, breeding in the tundra of northern Europe, from the Kola Peninsula to the Urals, and wintering in central Europe, Germany and the Netherlands. During very cold winters it is reaching France, northern Italy and Spain. This population is estimated at 300000 individuals, but its trends are not well known
Taiga Bean Goose status Least Concern

Migration

Migratory, winters mostly on coastal plains in NW and Central Europe and E Asia. Sporadically in more southern latitudes during cold winters.

Distribution map

Taiga Bean Goose distribution range map

Literature

Title Serological survey of viral pathogens in bean and white-fronted geese from Germany
Author(s): A. Hlinak, T. Muller, M. Kramer, R. U. Muhle, H. Liebherr, and K. Ziedler
Abstract: Sera from wild geese were tested for antibodies to..[more]..
Source: Wildl. Dis., Jul 1998; 34: 479-486

download full text (pdf)

Leave a Reply

Your email address will not be published. Required fields are marked *