Justification of Red List category
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). 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 extremely 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 to number 15,000,000 mature individuals (Partners in Flight 2020). The European population is estimated at 1,000-2,000 pairs, which equates to 2,000-4,000 mature individuals (BirdLife International 2015).
The overall population trend is increasing (Partners in Flight 2020; Wetlands International 2020). In North America the rate of increase is accelerating in recent years, amounting to 200% over the past three generations (Meehan et al. 2018). The Alaskan populations are estimated to be increasing (Amundson et al. 2019). In Europe the population size is also estimated to be increasing (BirdLife International 2015). Despite being hunted to regulate the population trend, the increase is continuing (Mowbray et al. 2020).
The following information refers to the species's range in Europe only. The species is found on low, grassy tundra, generally in close association with water (ponds, shallow lakes or river deltas) or on stony ground. Breeding begins in June usually as soon as areas become free of snow and generally within 7-10 days of arrival on nesting grounds. It is monogamous, often for life, although extra-pair copulations have been recorded. The nest is built by the female, who chooses the site as well and is a shallow depression filled with moss and lined with grass and down on the ground. Normally five or six eggs are laid. The diet is principally vegetarian, comprising of roots, tubers, leaves, grasses, stems and seed heads of various aquatic plants and sedges. The species is migratory (Carboneras et al. 2014).
Despite hunting pressure this species is increasing in numbers (Kear 2005; Mowbray et al. 2020). Climatic effects may impact the species in the future (Murphy-Klassen et al. 2005).
Conservation Actions Underway
CMS Appendix II.
Text account compilers
Ashpole, J, Butchart, S. & Ekstrom, J.
BirdLife International (2023) Species factsheet: Anser caerulescens. Downloaded from http://datazone.birdlife.org/species/factsheet/snow-goose-anser-caerulescens on 29/09/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 29/09/2023.