Information about the geese

GEESE IN SVALBARD

The migratory geese arrive in Svalbard from mid-May onwards. For arctic-breeding geese, body reserves brought to the breeding grounds are important for successful reproduction. The availability of tundra vegetation in years with an early spring thaw is also an important contributor to the birds’ breeding success. Snow cover conditions and the timing of the onset of spring therefore are crucial for the outcome of the breeding season in goose populations. The Arctic Fox is a significant threat to both eggs and goslings, and adult geese are also occasionally taken. Humans can pose a threat to the birds, in vulnerable time periods or at vulnerable sites, by disturbing the geese without the disturber being aware of it. In the brood-rearing period, when adults change their wing feathers (moult), neither the adults nor the unfledged young can fly. Escape distances (i.e. distances at which birds are displaced by human activity) in this period (July) may be several kilometres. The geese migrate back to their winter quarters in September each year.


Photo © G. Christensen

 

PINK-FOOTED GOOSE
(Anser brachyrhynchus)

The Svalbard-breeding population of pink-footed geese has increased significantly in recent decades. Counts made in winter and spring indicate that the population reached about 80 000 individuals by 2011/2012.

Pairs breed across much of Svalbard, but mostly in the western fjord systems. Nests may be located both on the slopes of the river valleys and on the tundra. Unlike other goose species in Svalbard, the pink-footed geese can defend themselves and the eggs/brood against arctic foxes, although the fox does occasionally manage to catch adult birds as well as the young.

Most non-breeders move to eastern parts of Svalbard for a 3–4 week period to moult, when they change wing feathers. As they cannot fly in this period, they are especially vulnerable to disturbance. The pink-footed goose is a quarry species - it is hunted in Svalbard, on the Norwegian mainland and in Denmark, but the birds are protected at their winter sites in the Netherlands (Friesland) and Belgium (Flanders).

A ringing programme organized by the University of Aarhus enables observers to recognize individual geese in the field, which can be identified by reading the unique letter- and number- codes on either blue or white neck bands. Some individuals also have colour rings on their legs.

 

 

BARNACLE GEESE
(Branta leucopsis)

The barnacle goose population in Svalbard fluctuated at around 25 000 individuals at the turn of the millennium, then increased to 35 000 birds by 2011/12. 

Only a few hundred individuals were recorded after the Second World War, but various successful management initiatives resulted in the population increasing to its current level. The population is protected throughout its range. In winter, the whole of the population is concentrated within a very small area  on the Solway Firth, on the border between England and Scotland, making them vulnerable at this time of year.

 In Svalbard, the barnacle geese nest either on steep slopes or on small islands to avoid fox predation. Recruitment is very limited at several of the colonies, however, due to predation of eggs or goslings (by foxes or polar bears) and/or density dependent processes (through a reduction in food availability). A large proportion of birds in the barnacle goose population is marked with coloured leg rings engraved with individual letter codes. 

The ringing programme is organized by the Wildfowl and Wetlands Trust (UK) and the University of Groningen (NL).


 

LIGHT-BELLIED BRENT GEESE
(Branta bernicla hrota)

The brent geese breeding in Svalbard belong to the light-bellied race. Counts in the winter- and spring staging areas in Jutland, Denmark, and Lindisfarne, England, suggest a population size of somewhere between 6000 and 7300 individuals (2011/2012). 

Most of the population is assumed to breed in Svalbard, but its status is currently uncertain.  Although numbers have increased slowly in recent decades, the production of young is variable and decreasing. Information from satellite-tagged geese shows that some brent geese continue their migration to northeast Greenland after arriving Svalbard in May/June. 

Brent geese may nest in extremely unproductive habitats, and, being the smallest of the three goose species in Svalbard, probably lose in competition with barnacle geese at several locations. Moreover, the brent geese breed in areas with high densities of polar bears, and nest predation rates may in some years be comprehensive. Arctic fox and avian predators also pose a considerable threat to brent goose eggs. 

The light-bellied brent goose is included on Svalbard’s threatened species red list (Category: “Near Threatened”) and is also the goose of which we have least knowledge. 

Individuals caught in Denmark, by the University of Aarhus, have been fitted with coloured leg rings engraved with letter codes so that individual birds can be identified in the field.


Photo © M. Bjerrang
 
Photo © C. Hübner
 
Photo © C. Hübner