Bean goose (Taiga bean goose & Tundra bean goose)

Anser fabalis

Rietgans / Saatgans / Oie des moissons

The bean goose is a goose that breeds in northern Europe and Asia. It has two distinct varieties, one inhabiting taiga habitats and one inhabiting tundra. These are recognised as separate species by the American Ornithologists' Union, but are considered a single species by other authorities, such as the British Ornithologists' Union. It is migratory and winters further south in Europe and Asia.

Anser fabalis (Sibley and Monroe 1990, 1993) has been split into A. fabalis (Taiga bean goose) and A. serrirostris (Tundra bean goose) by Sangster and Oreel (1996) and A. fabalis and A. middendorfi by Ruokonenet al. (2008). Given that these two treatments are contradictory and undermine one another's evidence we reject both treatments and retain one polyphyletic species A. fabalis.

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 (IUCN, 2012).

The species declined in the past due to hunting (resulting in mortality, injury and disturbance) (del Hoyo et al. 1992, Kear 2005a, Nikolaeva et al. 2006) and habitat loss (del Hoyo et al. 1992). Habitat degradation due to oil pollution (Grishanov 2006, Nikolaeva et al. 2006), drainage, peat-extraction, changing management practices (decreased grazing and mowing in meadows leading to scrub over-growth) and forest clearance is a threat to breeding areas in Russia (Grishanov 2006), Norway and Sweden (Madge and Burn 1988). The species also suffers from human persecution (Madge and Burn 1988) and is susceptible to poisoning by pesticides used on agricultural land (Kwonet al. 2004).

More information: http://www.iucnredlist.org/details/22679875/0

Above: adult Taiga bean goose, Anser fabalis fabalis

Above: adult Tundra bean goose, Anser fabalis rossicus

Above: adult Taiga bean goose, Anser fabalis fabalis

Above: adult Taiga bean goose, Anser fabalis fabalis

Above: adult Taiga bean goose, Anser fabalis fabalis

Above: adult Tundra bean geese, Anser fabalis rossicus