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 at c. 5,000,000-6,200,000 individuals (Wetlands International 2015). The European population is estimated at 1,000-5,000 pairs, which equates to 2,000-10,000 mature individuals (BirdLife International 2015).
The overall population trend is increasing, although some populations may be stable and some are decreasing (Wetlands International 2015). This species has undergone a large and statistically significant increase over the last 40 years in North America (1500% increase over 40 years, equating to a 101% increase per decade; data for Branta canadensis and B. hutchinsii combined, from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven 2007). The European population is estimated to be increasing (BirdLife International 2015).
This species has a large range, breeding across tundra in much of Canada, Alaska, U.S.A., and parts of the northern U.S.A., and wintering in southern North America, including Mexico. Introduced populations are now resident in much of the U.S.A. south of the normal breeding range, as well as in a number of western European countries. The subspecies asiatica, which occurred in the Bering Sea region, has been extinct since around 1914 (Fuller 2000).
The following information refers to the species's European range only. This species occurs in a wide diversity of habitats, from tundra to semi-desert and in wooded or open country and is frequently found in agricultural or urban areas in Europe although almost always found near water. The species is generally monogamous and egg-laying begins in mid-March. It builds a shallow nest of vegetation, lined with down and feathers, on ground, frequently near waterbodies. Clutches are usually four to seven eggs (Carboneras et al. 2014). The diet is primarily plant materials, including stems, leaves, tubers, fruits and seeds (Snow and Perrins 1998). Natural populations found in Greenland are mainly migratory, wintering in the southern states of the U.S.A. and along coasts of North America (Carboneras et al. 2014). In Europe, it is sedentary in some areas and migratory in other, and a moult migration takes place (Snow and Perrins 1998).
Although hunting and other direct mortality takes a substantial toll, this species has increased its range and population since the 1940s (Mowbray et al. 2002). Temperate breeders in Europe are frequently in conflict with human activities, for example, they may cause fouling of parks, golf courses or other recreational areas but also cause considerable crop damage in spring-winter to wheat and hayfields, and in the autumn to unharvested grains. As a result in Europe, farmers are permitted to scare or exceptionally shoot geese. In Sweden numbers killed rose from 17,000 in 1990 to 20,000-25,000 in 1996, with smaller numbers shot in Denmark, Germany and Norway. In addition, local governments with nuisance problems can request permission to destroy nests and eggs (Carboneras et al. 2014).
Conservation Actions Underway
The following information refers to the species's range in Europe only. EU Birds Directive Annex II. CMS Appendix II. The species is not legal quarry in the Netherlands or Belgium (Kear 2005).
Conservation Actions Proposed
The following information refers to the species's range in Europe only. No conservation measures are currently needed for this species.
Text account compilers
Butchart, S., Ekstrom, J., Khwaja, N., Pilgrim, J., Ashpole, J
BirdLife International (2017) Species factsheet: Branta canadensis. Downloaded from http://www.birdlife.org on 23/11/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 23/11/2017.