Barnacle Goose populations
WeBS treatment of Barnacle Goose populations:
- Reports to 2010/11 - Greenland Barnacle Goose; Svalbard Barnacle Goose &; Naturalised Barnacle Goose.
- Reports from 2011/12 - Greenland Barnacle Goose; Svalbard Barnacle Goose; Naturalised barnacle Goose &; 'generic' Barnacle Goose.
Two distinct populations of Barnacle Goose Branta leucopsis are known to winter in the UK. Barnacle Goose from the Svalbard population are known to winter at three principal sites in the UK: Solway Firth, Lindisfarne and Loch of Strathbeg. Those from the Greenland population winter chiefly in the Western Isles. In addition to these two migratory populations, the UK has an increasing population of naturalised Barnacle Goose.
Individuals of these three populations are indistinguishable in the field. Consequently, all but a few records received by WeBS refer simply to 'Barnacle Goose'. When reporting this species, WeBS assumes that records from any of the three sites associated with the Svalbard population belong to that population, records from elsewhere in Scotland belong to the Greenland population, and remaining records belong to the naturalised population. However, the Svalbard population continues to increase and birds from this population may begin to expand their winter range within the UK.
WeBS allocation of populations for reporting purposes:
- Greenland Barnacle Goose: All records of Barnacle Goose from Scotland other than the Solway Estuary and Loch of Strathbeg. Any record specifically reported as Greenland Barnacle Goose.
- Svalbard Barnacle Goose: All records of Barnacle Goose from coastal counties bordering the Solway Estuary, Loch of Strathbeg or Lindisfarne. Any record specificaly reported as Svalbard Barnacle Goose.
- Naturalised Barnacle Goose: All records of Barnacle Goose from England and Wales but excluding those from north Cumbria. Any records reported specifically as naturalised Barnacle Goose.
- Barnacle Goose (from winter 2011/12): All records of Barnacle Goose.
WeBS reporting of annual trends:
- Greenland Barnacle Goose: WeBS does not calculate annual trends for the Greenland population but rather reports trends derived from the annual WWT/JNCC/SNH winter census. Monthly trends are derived from WeBS data.
- Svalbard Barnacle Goose: WeBS does not calculate annual trends for the Svalbard population but rather reports trends derived from the annual WWT/JNCC/SNH winter census. Monthly trends are derived from WeBS data.
- naturalised Barnacle Goose: both annual and monthly trends are derived from WeBS data.