speciesaccounts_barnaclegooseGreenland Barnacle Goose

 Branta leucopsis

The Greenland Barnacle Goose breeds in northeastern Greenland and winters almost entirely along the west coasts of Scotland and Ireland. The main concentration is found on the isle of Islay, Scotland, which regularly supports over 50% of the population.

Ringing studies have shown that Greenland Barnacle Geese are very faithful to specific wintering sites, with 70% of birds returning to the same site during the following winter.

  • Conservation Status

    Global status (IUCN Red List of Threatened Species)

    African-Eurasian Waterbird Agreement (AEWA)

    European status (European Red List of Birds)

    The Birds Directive (European Commission)

    UK status (Birds of Conservation Concern)

    UK quarry species (Wildlife & Countryside Act 1981)

    Least Concern

    B1

    Least Concern (Europe and EU27)

    Annex I

    Amber

    not huntable, but licensed control occurs in Scotland

    Population Status

    Flyway population size (CSR 6; Wetlands International 2015)

    GB estimate (Musgrove et al. 2011)

    Irish estimate (Crowe & Holt. 2013)

    GB trend (SUKB 2017)

    Breeding success (GSMP survey)

    80,700 individuals

    58,000 individuals

    15,370 individuals

    Long-term trend (1989/90 – 2014/15): 175% increase
    Ten-year trend (2004/05 – 2014/15): 57% increase

    Highly variable, generally 3-13% during 1993-2011

    Summary statistics

    Estimates of population size of Greenland Barnacle Goose, 1959-2018; recorded during the International Census of Greenland Barnacle Geese.

    Census year Estimate of population size
    2018 72,162
    2013 80,670
    2008 70,501
    2003 56,386
    1999 54,123
    1994 38,012
    1988 34,542
    1983 25,252
    1978 33,815
    1973 24,082
    1966 19,797
    1962 13,990
    1961 13,904
    1959 8,321

    Annual estimates of the percenatage of young (%) and mean brood size (young per successful pair) of Greenland Barnacle Goose, 2004/05-2016/17; recorded on the isles of Islay, Scotland where data have been collected regularly.

    Season Percentage of young (%) Mean brood size
    2017/18 5.3 1.92
    2016/17 17.9 2.21
    2015/16 5.6 1.51
    2014/15 2.7 1.40
    2013/14 5.5 1.78
    2012/13 7.0 1.80
    2011/12 11.2 2.10
    2010/11 11.2 2.26
    2009/10 4.0 1.80
    2008/09 8.2 1.86
    2007/08 9.8 2.12
    2006/07 3.2 1.16
    2005/06 6.6 1.76
    2004/05 15.9 2.35

     

    References

    Crowe, O. & C. Holt. 2013. Estimates of waterbird numbers wintering in Ireland, 2006/07-2010/11. Irish Birds 9: 545-552

    Musgrove, A.J., G.E. Austin, R.D. Hearn, C.A. Holt, D.A. Stroud & S.R. Wotton. 2011. Overwinter population estimates of British waterbirds. British Birds 104: 364-397.

  • The Greenland population of Barnacle Goose breeds in northeastern Greenland. Migration begins in late August/early September, and birds use stop over sites in southeast Iceland. The geese begin to leave Iceland from late September and by November they have all reached the British and Irish wintering grounds. Ringing studies have shown that Greenland Barnacle Geese are very faithful to specific wintering sites, with 70% of birds returning to the same site during the following winter.

    flyway map barnacle_greenland

    Flyway of the Greenland Barnacle Goose

    The islands off the west and north coasts of Scotland and Ireland (as well as several mainland sites) support the entire population during the winter. The main concentration is on the island of Islay, with 78% of the Scottish total and 56% of the overall population occurring there in 2013 (Mitchell & Hall 2013). As numbers on Islay have steadily increased, some other key sites – notably Coll and Tiree (Inner Hebrides) and South Walls (Orkney) – have also become increasingly important, possibly as a result of an increase in intensively managed grasslands providing more favourable feeding habitat, as well as the establishment of Goose Management Schemes. Some smaller, uninhabited islands are now less used, possibly due to habitat changes possibly brought about by cessation of grazing. There have been some substantial changes in distribution since surveys began in 1957, when the population was equally divided between Islay, the rest of Scotland, and Ireland. Since then, numbers have increased on Islay which, in 2003, held 65% of the total population and 56% in 2013.

    Traditionally, saltmarshes, coastal pastures and islands were selected as favoured feeding areas, but more recently the requirement for short-cropped sward has been met by intensively managed grasslands. The geese feed on grasses, herbs, leaves, stolons and seeds, as well as barley and oat stubbles, spilt grain and undersown grass. Since the mid-twentieth centuray there has been an increase in the use of agricultural fields as feeding grounds. Most conflict occurs on Islay, as well as some of the other inhabited islands off the north and west coast of Scotland. To alleviate these conflicts, Goose Management Schemes are now in operation on Islay and South Walls, Orkney.

    References

    Mitchell, C., A. Walsh, C. Hall & O. Crowe. 2008. Greenland Barnacle Geese Branta leucopsis in Britain and Ireland: results of the international census, spring 2008. Wildfowl & Wetlands Trust, Slimbridge.

    Ogilvie, M.A., D. Boertmann, D. Cabot, O. Merne, S.M. Percival & A. Sigfusson. 1999. Barnacle Goose Branta leucopsis: Greenland. In: Madsen, J., G. Cracknell & A.D. Fox (eds.). 1999. Goose populations of the Western Palearctic. A review of status and distribution. Wetlands International Publication no. 48, Wetlands International, Wageningen, The Netherlands/National Environmental Research Institute, Ronde, Denmark.

  • Annual counts and age assessments at key sites

    Due to many Greenland Barnacle Goose wintering sites being remote inaccessible islands, a complete census of the population is not possible every year, as aerial surveys are required to cover such areas. Annual counts are, however, undertaken at several key sites in Scotland. Two comprehensive counts are organised by Scottish Natural Heritage (SNH) on Islay, and monthly counts are also carried out by SNH at South Walls, Orkney. The RSPB undertake at least two counts during the winter on the Inner Herbridean isles of Coll, Tiree, Colonsay and Oronsay.

    Age assessments are also carried out on Islay and Tiree, where counters record the number of young present in flocks as well as individual brood sizes (i.e. the size of family groups).

    Results from these surveys are summarised on the ‘Latest Results’ tab.

    Find out more about age assessments

    International Census of Greenland Barnacle Goose

    A census of the entire Greenland Barnacle Goose population is undertaken every five years. The census covers Ireland and north and west Scotland and involves both ground counts and aerial surveys, the latter covering the inaccessible areas.

    Results from these censuses are presented in various reports and papers. See our Reports and newsletter page.

    Find out more about the International Census of Greenland Barnacle Geese

  • Results from 2017/18 [added September 2018]

    Abundance

    International Census 2018

    In March 2018, the most recent flyway-wide census of Greenland Barnacle Geese took place, including those parts of the winter range that need to be checked using a light aircraft. The full results from the census are presented in Mitchell & Hall (2018).

    The population estimate was 72,162, a 10.5% decrease on the last complete census conducted in 2013 (80,670). In Ireland, 16,237 birds were counted, a decrease of 7.2%. In Scotland, 229 sites were surveyed, including 190 islands by aerial census and Barnacle Geese were found at 39 sites (Figure 1). A total of 55,424 birds were counted and an estimate of 501 birds were included from one site, giving a total of 55,925 birds, a decrease of 11.5% since 2013. Islay was the most important site with 34,750 birds counted (Table 1) – 22.6% lower than the number recorded there five years previously.

    Compared to 2013, there were increases in numbers in areas surrounding Islay; numbers on Tiree and Coll increased by 17.8% to 6,477 and, on North Uist (mainland), numbers increased by 68.9% to 5,950.

    Figure 1. The distribution of Greenland Barnacle Geese in Scotland recorded during the mid-March 2018 international census.

    Table 1. Counts of Greenland Barnacle Geese made during the March 2018 survey of over 1% of the Scottish total.

    Site Area Count in 2013 Count in 2018 % change
    Islay Argyll 44,914 34,750 -22.6
    Tiree Argyll 4,518 5,126 13.4
    Oronsay Argyll 2342 2,250 -3.9
    South Walls Orkney 1740 1460 -16.1
    Balemore/Paible North Uist 37 1442 3797
    Coll Argyll 980 1266 29.2
    Ahmore North Uist 0 921
    Berneray North Uist 975 745 -23.6
    Balranald/Goula North Uist 541 677 25.1
    Isle of Danna Argyll 704 650 -7.7
    Vallay North Uist 88 610 593
    Griminish North Uist 0 610

     

    Annual counts at key sites

    On Islay, the most important wintering site in the UK for Greenland Barnacle Geese, up to four co-ordinated counts were undertaken during winter 2017/18. These revealed 48,366 birds in November, 43,351 in December, 37,487 in January and 34,750 in March. The mean of these four counts was 40,989 birds which represents a 12.2% decrease compared to winter 2016/17 (mean 46,714 geese, Figure 2). The November 2017 count was 5,000 birds higher than the count a month later and 13,600 higher than the March 2018 count. The November count presumably included transient geese that did not stay to winter on Islay and, in addition, 3,321 birds were shot there during the winter.

    Figure 2. Adopted counts (mean of the winter counts) of Greenland Barnacle Geese on Islay, 2008/09-2017/18.

    Breeding success

    Breeding success is measured annually on Islay and counts in autumn 2017 revealed a poor breeding season. Just over 9,000 birds were aged and 5.3% were young, with a mean brood size of 1.92 young per successful pair (Table 2).

    Table 2. The percentage of young and mean brood size of Greenland Barnacle Geese during winter 2017/18.

    Site Number aged Percentage of young (%) Mean brood size
    Islay 9,015 5.3 1.92
    Tiree 300 3.3 1.11
    Durness 200 6.0 1.33
    Kyle of Tongue 204 0.5 1.00
    Oronsay 226 10.2
    North Uist 412 5.6 1.40
    Overall 10,357 5.3 1.79

     

    Figure 3. Percentage young (blue columns) and mean brood size (red circles) of Greenland Barnacle Goose on Islay (where data have been collected regularly), 1961/62–2017/18.

    Discussion

    The census in March 2018 indicated that the flyway population has decreased by 10.5% to 72,162 birds compared to 2013. The long-term increase in numbers, from the 1950s up to 2013, seems to have been halted. Up to c.2,000 Greenland Barnacle Geese are shot in Iceland each year and licences to shoot up to #### on Islay have been issued by the Scottish Government in recent years. It may be that this level of mortality, combined with relatively low annual productivity in the last ten years is keeping population growth in check.

    Several key sites in Scotland hold the majority of Greenland Barnacle Geese with the majority wintering on the Inner Hebridean island on Islay (Table 1). The decrease in numbers on Islay of 22% compared to March 2013 involves birds recorded on the island at the end of winter. Ring-recovery information has shown that November counts on Islay include some transients (birds that stage on Islay during the autumn and move on to winter elsewhere within the range).

    Increases in the number of Greenland Barnacle Geese on Tiree and Coll, and notably on North Uist (although interestingly not in Ireland), may, in part be due to birds moving from Islay due to the disturbance caused by the culls being carried out there.

    Results from age assessments conducted during autumn 2017 on Islay (from where the largest sample is provided) show that the 2017 breeding season was poor; the figure of 5.3% young recorded on Islay being similar to the previous ten-year mean of 6.8% (± 1.0 SE). Mean brood size on Islay in 2017 was also slightly higher than average at 1.92 young per successful pair, compared to the previous ten-year mean of 1.88 young (± 0.1 SE).

    Acknowledgements

    Thanks are extended to Malcolm Ogilvie, Andy Knight and John Bowler for providing age counts, and the volunteer counter network, SNH and RSPB for providing additional counts.

    References

    Mitchell, C. & C. Hall. 2018. Greenland Barnacle Geese Branta leucopsis in Britain and Ireland: results of the international census, spring 2018. Wildfowl & Wetlands Trust Report, Slimbridge.

  • Previous annual results will be archived here. Published results from previous international censuses can be found on the Reports & newsletter page.

    2016/17 Results

    2015/16 Results

    2014/15 Results

    2013/14 Results

    2012/13 Results

    2011/12 Results

    2010/11 Results

    2009/10 Results

    2007/08 Results: including 2006/07 breeding success results

    2006/07 Results: including 2005/06 breeding success results

    2005/06 Results

  • Survey results

    International census reports: See the Reports & newsletter page

    Wetland Bird Survey Alerts

    Wetland Bird Survey annual report

    Relevant publications

    Mitchell, C., C. Hall & A. Douse. 2009. Greenland Barnacle Geese in Scotland in 2008. Scottish Birds 29: 99-100.

    Walsh, A.J. & O. Crowe. 2008. Barnacle Geese Branta leucopsis in Ireland, spring 2008. Irish Birds 8: 430-432.

    Other relevant material

    BirdLife International Species factsheet

    British Trust for Ornithology: BirdFacts

    Review of Goose Management Policy in Scotland 2010

    Hunting in Iceland: The numbers of Greenland Barnacle Geese hunted in Iceland are available here.

    SNH Islay Sustainable Goose Management Strategy

    SNH Islay Goose Management Scheme

     

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