Justification of Red List Category
This species has a very 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). The population trend appears to be increasing, and hence the species does not 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.
The global population is estimated at c. 880,000 individuals (Wetlands International 2015). The European population is estimated at 196,000-247,000 pairs, which equates to 392,000-494,000 mature individuals (BirdLife International 2015).
The overall trend is suspected to be increasing (Wetlands International 2015). The European population is increasing (BirdLife International 2015).
Behaviour This species is fully migratory and travels on a narrow front (Kear 2005a) between extremely localised breeding and wintering areas (del Hoyo et al. 1992). It is present on its breeding grounds from May or June to August or September (Kear 2005a) where it breeds in small but often closely packed colonies (Madge and Burn 1988, del Hoyo et al. 1992) of 5-50 pairs, occasionally singly or in groups of up to 150 pairs (Snow and Perrins 1998). It uses the same nesting sites year after year (Johnsgard 1978) and sometimes nests among seabird colonies (Madge and Burn 1988). After the young hatch the adults undergo a flightless moult period near the breeding grounds between mid-July and mid-August that lasts for 3-4 weeks (Scott and Rose 1996). The species migrates to autumn staging areas in September (Kear 2005a) from which it travels via regular stop-over sites (Madge and Burn 1988) to the wintering grounds, arriving in late-September (Kear 2005a). The return migration begins in April or May, the species moving to spring staging areas where it may be present for 20-30 days before migrating northwards (Kear 2005a). The species is highly gregarious outside of the breeding season, often feeding in dense concentrations on coastal grasslands during the winter (Madge and Burn 1988). In winter habitats it roosts on water (Madge and Burn 1988) or on sandbanks near saltmarshes and pastureland (Peberdy 1991). Habitat Breeding The species breeds in Arctic semi-desert tundra (fjellmark) (Kear 2005a)on crags, rocky outcrops (del Hoyo et al. 1992), cliffs, rocky slopes (Johnsgard 1978) and coastal islands (Svalbard) (Kear 2005a) near wetlands such as lakes, rivers, marshes, the upper parts of fjords, coastlines (Johnsgard 1978), wet meadows and mudflats (Kear 2005a). In years when the snow is slow to melt the species first forages on grassy vegetation on south-facing mountain slopes fertilised by the droppings of cliff-nesting seabirds before moving down to breeding areas (Kear 2005a). It also returns to these slopes after the moulting period before autumn migration (Kear 2005a). After the young hatch families may disperse away from rocky ground to more vegetated areas surrounding tundra lakes and rivers (Kear 2005a). Non-breeding During the non-breeding season the species frequents tidal mudflats, saltmarshes (Johnsgard 1978, Kear 2005a) and adjacent coastal meadows (Johnsgard 1978, del Hoyo et al. 1992) (especially improvedrough pasturesand arable land (del Hoyo et al. 1992, Kear 2005a)), with agricultural fields becoming increasingly more important as winter feeding areas (Scott and Rose 1996). Diet The species is herbivorous (del Hoyo et al. 1992) its diet consisting of the leaves, stems and seed-heads of grasses, sedges, aquatic plants (del Hoyo et al. 1992, Kear 2005a), mosses (Kear 2005a), various herbs (especially white clover Trifolium repens in the winter) (Peberdy 1991, Vickery and Gill 1999) and shrubs (e.g. arctic willow Salix arctica) (Johnsgard 1978). It may also take agricultural grain and vegetables during the winter (del Hoyo et al. 1992). Breeding site The nest is a shallow depression in a low mound of vegetation (Snow and Perrins 1998) positioned on rocky ground (del Hoyo et al. 1992, Kear 2005a), rocky outcrops (Johnsgard 1978, Snow and Perrins 1998), among rocky crags, on steep cliffs (Johnsgard 1978, Madge and Burn 1988, Snow and Perrins 1998), on the tops of low hills (Johnsgard 1978), or on low vegetation hummocks and snow-free patches on islands in river channels (Snow and Perrins 1998). Nesting sites accumulate nesting materials as they are often used year after year (Johnsgard 1978), and the species may sometimes nest among seabird colonies (Madge and Burn 1988). Management information An investigation carried out in one of the species's wintering areas (UK) found that it was most likely to forage on improved grasslands with high abundances of the grass Lolium perenne and white clover Trifolium repens (Vickery and Gill 1999) (the growth of which is greatly influenced by the amount of summer grazing, which controls the grass height) (Peberdy 1991). Preferred fields were between 4 and 10 ha in area (the species avoided fields of less than 2-3 ha), and at an optimal distance of less than 5 km away from roosting sites (maximum 7 km away) (Vickery and Gill 1999). The species was also found to show a preference for grasslands with swards less than 10 cm in height (optimum 2 cm) in fields that had been cut for silage and then grazed (although there was no major difference in feeding intensity on pastures grazed with different livestock) (Vickery and Gill 1999). Overall winter use of grassland fertilised with large amounts of nitrogen was significantly greater than the use of unfertilised grassland by the species (Vickery and Gill 1999). The Barnacle Goose Management Scheme (BGMS) in Scotland, UK recommends fertilising farmland adjacent to reserves containing wintering groups of this species at times when geese are present (e.g. autumn or winter) and grazing stock (sheep or cattle) are absent (Cope et al. 2003). The BGMS also awards payments to farmers who manage pastures outside of established reserves for reducing the level of disturbance (e.g. scaring away feeding flocks) on their land (Cope et al. 2003).
Today the species is fully protected throughout its range, although adults, eggs and down were once exploited by humans (Kear 2005a), and the species may be disturbed by shooting even though it is not directly hunted (Peberdy 1991). The species faces possible threats from persecution (disturbance) by farmers as in winter it favours grasslands and pastures used for grazing livestock (Cope et al. 2003). The species also suffers from nest predation by arctic fox Vulpes lagopus in Svalbard (Madsen et al. 1992).
Conservation Actions Underway
Bern Convention Appendix II. EU Birds Directive Annex I. CMS Appendix II. Today the species is fully protected throughout its European range (Kear 2005). The Barnacle Goose Management Scheme (BGMS) awards payments to farmers who manage pastures outside of established reserves for reducing the level of disturbance (e.g. scaring away feeding flocks) on their land. Its efforts, integrating conservation and agricultural aims, have succeeded in increasing goose populations around the Solway Firth, U.K. (Cope et al. 2003). The species is also listed on the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA).
Conservation Actions Proposed
The expansion and quality of measures that integrate conservation and agricultural aims, should be expanded and the dedicated reserve network increased (Cope et al. 2003). Research should be undertaken to investigate the impacts of Arctic Fox predation on Svalbard.
Text account compilers
Butchart, S., Ekstrom, J., Malpas, L., Ashpole, J
BirdLife International (2020) Species factsheet: Branta leucopsis. Downloaded from http://www.birdlife.org on 28/11/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/11/2020.