GWGS

The Greenland White-fronted Goose
Anser albifrons flavirostris
Latest field trip: Greenland 2010
Latest update: Archive video of the first 1979 expedition added, Spring 2010 report, small sites report

The Greenland White-fronted Goose, Anser albifrons flavirostris, breeds in west Greenland, and migrates via Iceland to winter in Ireland and Britain. It is the most distinctive race of the circumpolar White-fronted Goose that nests throughout most of northern Russia, Arctic Canada and Alaska.

Greenland whitefront

The Greenland White-fronted Goose has been on conservation concern for many years. Declines from the 1950s to the late 1970s resulted in debate about its effective protection and the creation of the Greenland White-fronted Goose Study in 1978 and the initiation of studies on the breeding grounds in Greenland. The process also forged an excellent collaboration between a wide range of enthusiasts, non-government organisations and government departments which continues to the present day. The law was changed to protect the population from hunting in Ireland and Scotland from 1983 onwards, and a network of observers was established in 1982 to undertake regular winter counts at all the known haunts to monitor the changes in abundance of the entire population. A programme of research was also initiated which included regular capture and marking of individuals at Wexford Slobs by the National Parks and Wildlife Service in Ireland.

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The Greenland White-fronted Goose Study census network

The first description of the numbers and distribution of wintering flocks of Greenland White-fronted Geese in Ireland and Britain was compiled by Major Robin Ruttledge and Malcolm Ogilvie and published in the 1979 volume of Irish Birds. For most Irish flocks, often wintering in remote bogland habitats, there were no regular counts to give a clear and accurate picture of the status of the population. Many of the flocks they described for the first time are incredibly difficult to access, let alone count simultaneously, making it difficult to compile counts at flock or national level. Their pioneering paper showed that, based on available evidence, wintering numbers had apparently declined in the two countries from 17,500-23,000 in the 1950s to 14,300-16,600 by the mid-1970s. Such was the concern raised, that the population was protected from hunting on the wintering grounds under legislation enacted in Ireland and the United Kingdom, effectively starting in the winter of 1982/83.

This confirmed the need for adequate monitoring, if nothing else, to see if legislative change would be effective in restoring the population to favourable conservation status. To this end, the Greenland White-fronted Goose Study (an independent study group based at the University College of Wales, Aberystywyth) attempted to establish complete count coverage of all known wintering sites in Great Britain. In Ireland, the then Forest and Wildlife Service (latterly Dúchas, with help from the RSPB in Northern Ireland) set up a count network, mostly comprising professional Ranger staff. Thanks to these efforts, annual survey of all known winter resorts has continued to the present day, and we enjoy a far better perspective over the fortunes of the population than was the case 25 years ago.

The counts show the Greenland White-fronted Goose represents a conservation success story. After removal of hunting mortality in Ireland and Britain (although the shooting moratorium was lifted at Wexford in 1985/86 and 1989/90 with strict bag limits in both years), numbers increased at a rate expected if the previous hunting mortality had been “additive”. That is to say, that the birds killed were not some “doomed surplus” that would have died anyway (perhaps through disease or starvation), but their deaths added to those from natural causes. Thanks also to run of good breeding years in the 1980s, numbers increased rapidly to peak of 35,500 in the late 1990s (Figure 1).

Last winter’s counts confirm a rather dramatic recent decline in numbers over the course of just three seasons. Numbers have fallen rapidly back to less than 27,000 last winter (2001/2002), disguised a little by the missing spring 2001 count (because of the Foot and Mouth epidemic, spring numbers were estimated on the basis of the autumn count). Interestingly, numbers at Wexford Slobs (the single most important Irish wintering site) actually stabilised and began to decline from the mid-1990s, long before the overall recent declines. The change in Wexford numbers can be explained by constant annual survival (based on resightings of collared individuals, thanks to the large Dúchas marking project on the site) and observed declines in breeding success.

So why this spectacular recent decline? Annual survival has been relatively constant, and based on the movements of collared birds, emigration from Wexford to other winter resorts is no higher now than in previous years. The international monitoring programme also samples the proportions of young in the population. First winter birds can be distinguished from older birds by lack of white on the face and black bars on the belly, so it is possible to assess the numbers of young in the population in winter. There has been a long-term decline in the percentage of young birds returning to Wexford, and a similar trend (although not statistically significant) on Islay, the single most important Scottish wintering site, since protection (see Figure 2). Production of young at Wexford has been below average in 8 out of the last 10 years, with the result that the number of new recruits to the population has failed to replace annual losses. It is this phenomenon that has caused the stabilisation and decline in numbers at Wexford, and the same pattern is undoubtedly responsible for the declines throughout the wintering range. The average age of first breeding amongst known-age collared birds captured at Wexford has gone from just over 3 years in the 1980s to nearly 6 years in the 1990s, showing it is becoming harder for young birds to breed. Currently less that 5% of marked goslings survive to breed at all compared to over 20% in the early 1980s. It’s pretty tough being a White-fronted gosling: it is getting very difficult for new birds to reproduce at all.

So what has caused these declines in breeding success? At present we cannot be sure. They follow a period of increase in the population, so it may be a “density dependent” effect. If some resource limits the numbers of geese able to breed successfully, the expansion in numbers may now have reached the capacity of available breeding habitat. Weather plays a part geese return with most young after an early spring thaw and a warm summer. Five out of the last 6 spring and summers have been cool in west Greenland, and this has doubtless contributed. This has a disproportional effect on geese breeding in the north of range, where the breeding season is shortest. Ringing recoveries and satellite tracking has shown birds breeding in the far north tend to winter at Wexford and in the south of the wintering range, so this fits with the pattern of earlier declines there. Scottish wintering birds (including those on Islay) originate from the southern breeding range, where longer seasons buffer effects of delayed springs, and where the declines in production have been less marked. Finally, the colonisation of west Greenland by large numbers of breeding Canada Geese Branta canadensis should be mentioned. These are birds of the interior race, probably originally from northern Quebec that have been arriving in increasing numbers to areas of west Greenland formerly only inhabited by Whitefronts. Although both species coexist in large parts of the Canadian arctic, recent studies have shown that Canada Geese are behaviourally dominant over White-fronted Geese in Greenland, and that in one study area they have continued to increase and completely displace the native species. We do not have a good idea about the scale of this effect, but the speed of this process gives cause for concern that inter-specific competition could contribute to falling breeding success amongst Greenland White-fronted Geese.

Whatever the solution to this complex problem, one thing is becoming clear. The kill in Iceland has been increasing in recent years, the official bag has risen from 2,947 in 1996 to 3,685 in 2001. Because of the decline in total population size, this means that the proportion shot has increased from 8% to 12%. Whilst it is clear that the autumn hunt in Iceland was sustainable during the period of population expansion of the 1980s and 1990s, the present level of kill cannot assist in returning the population to favourable conservation status. While the cessation of the autumn hunt there cannot halt the current decline in the overall population, it is one tangible conservation action that will contribute to the slowing of the rate of decrease in numbers.

It is important that the management plan, drafted and agreed for this population in Wexford, Ireland in 1992 but never formally signed by the range states (Ireland, United Kingdom, Iceland and Greenland), be reconvened and updated, to establish research and monitoring priorities for action. Actions must be targeted to secure the population for the future to ensure that the international investment in the protection of the population that occurred in the 1980s and 1990s was not in vain.

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Broubster Leans SSSI becomes RSPBs latest reserve acquisition

Broubster Leans SSSI has just become the lastet reserve to be acquired by the Royal Society for the Protection of Birds, adding another layer of site sfaeguard to this important wetland and the most regularly used roost site for the Westfield flock of Caithness wintering Greenland White-fronted Geese.

The press release reads:

Bright future for mainland Britain’s most northerly wetlands

One of the most important breeding sites in northern Britain for wading birds is to become the RSPB’s latest nature reserve thanks to generous membership donations.

Broubster Leans – a rich and beautiful wetland that has developed on the floodplain of the Forss Water 7 km south west of Thurso – is the latest addition to RSPB’s suite of nature reserves in Scotland that will be managed for the benefit of the wide variety of birds, plants and insects that have made this habitat their home.

The site is an ideal place for wildlife, due to its diverse mosaic of wet grasslands, pools, mires and drier pastures, and this is reflected in the multiple designations it already carries, including Site of Special Scientific Interest (SSSI), Special Protection Area (SPA) and Special Area of Conservation (SAC). Traditional farming, particularly extensive cattle grazing, has been essential in maintaining this mixture of habitats.

Throughout the year hen harriers, twite and short-eared owls are present; greenshank, golden plover, lapwing, snipe, redshank and common sandpiper breed on the reserve in the summer months, and in winter it serves as a refuge for two hundred Greenland white-fronted geese and up to 80 whooper swans. Even the rare spotted crake and the water vole can be found on the reserve.

However, in the past decade the number of waders in the area has halved from around 100 pairs to just 50. In coming years RSPB aims to reverse this decline and get the wader population back up to about 250 pairs.

The new reserve – 200 ha of which has been bought, with a further 100 ha under a management agreement – forms about one fifth of the total wetland area at Broubster. Management of the reserve will focus on working with local farmers to improve grazing and cutting of the wet centre of the Leans and to reinstate an arable rotation on the drier parts of the wetland. RSPB hopes that this will demonstrate how sympathetic farming can work in tandem with nature conservation to produce benefits for wildlife, farmers and the future of the countryside.

Dr Peter Mayhew, RSPB’s senior conservation manager for north Scotland, said: “For many years RSPB has worked hard to acquire a reserve in this magical part of Scotland where some of our best loved species can thrive, so this is a fantastic opportunity for us.

“Over the last twenty years we have seen an alarming decrease in some of our wader and farmland bird populations, coupled to the loss of wetland habitat and changes in land management practices. At Broubster the delicate balance of pasture, fen and wetland that have been established over centuries of human interaction with the land makes this an exceptional area despite it being one of the toughest farming environments in the UK. Working with local farmers and crofters, we hope to restore the habitats for breeding birds like lapwing, snipe and redshank whilst maintaining the wintering populations of geese and swans. We also hope to bring back the great yellow bumble bee to Broubster, one of the most threatened insects in Britain, a few colonies of which are found close by.

“Caithness has nationally important populations of waders on a number of different sites scattered throughout the County. Broubster will be a demonstration project to trial new management techniques to help restore these other wetlands, in partnership with local farmers. There will also be a new vacancy for a reserve warden at Broubster to take forward management on this site and throughout the Caithness wetlands. This will be a great opportunity for someone to work for wetlands in the north and create a bright future for wintering and breeding birds. With the development of modest visitor facilities at Broubster and elsewhere we would hope to attract many more birdwatchers to the area.”

ENDS.

For more information/interviews/images, please contact RSPB Scotland’s Head of Media James Reynolds on 0131 311 6500/07725065186.

Notes.
The Leans is a 1,500 ha floodplain located about 7 km southwest of Thurso. It is an area of fen/mire/grassland within a farmed landscape – typical of the Caithness wetlands. It is part designated as a SSSI, SPA, SAC, RAMSAR and is part of the Caithness Lochs Important Bird Area. The main notification features are blanket bog, transition mire/quaking bog, breeding birds and wintering wildfowl. The Caithness wetlands have been identified as one of the most important wetland areas in the UK for intensive conservation action by the RSPB.
Broubster Leans is threatened due to agricultural abandonment of the wetter areas, less sympathetic management of the drier sections and afforestation of abandoned areas. Essentially, on the wetter parts of the site the problem is lack of grazing and cutting of the fen vegetation. This leads to build up of plant material that discourages waders. We would address this by working with farmers to get cutting and grazing onto these sites. On drier parts of the reserve, the problem is too much sheep grazing. We will reduce stock numbers and introduce arable management that should help passerines as well as waders like lapwings. In the long-term, we would hope to encourage corncrakes and great yellow bumblebee to the site.
Important non-avian species present at the site include otter and the nationally scarce narrow small-reed Calamagrostis stricta. The wetland bird population of Broubster Leans has historically been notable in terms of the number of species it supports. Nine species of wader (oystercatcher, lapwing, snipe, curlew, redshank, greenshank, wood sandpiper, common sandpiper and dunlin) have bred at the site. In addition, the site has attracted calling spotted crake and summering common crane and marsh harrier. Hen harriers use the site throughout the year and short-eared owls are regular in good vole years but do not breed there. The site regularly supports a wintering population of 200 Greenland white-fronted geese, which is at the 1% threshold for national importance for this species. The trend for this flock is a slow increase, in contrast to the national population. Broubster Leans is also regionally important for other wintering wildfowl such as whooper swan, Icelandic greylag goose and a range of duck species. It is also suitable for great yellow bumblebee management, for which RSPB is a lead BAP partner.
Although designated site condition monitoring reports the Leans as being in favourable condition, this is not the case for breeding waders. In 2005, the IBA (620 ha) held 44 pairs of waders: some 40% of the mid-1990s level of 105 pairs. With appropriate management, wader populations could be increased to 250+ pairs based on densities in similar habitats elsewhere.

The Royal Society for the Protection of Birds Scotland

Dunedin House

25 Ravelston Terrace

Edinburgh

EH4 3TP

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Background notes for press release

1. The Greenland White-fronted Goose Anser albifrons flavirostris is the most distinct sub-species of the circumpolar White fronted Goose Anser albifrons.  It breeds in west Greenland and migrates through Iceland to winter exclusively in Britain and Ireland, where it remains one of the rarest of wintering goose populations. 

2. The population declined from 17,500-23,000 in the 1950s to 14,300-16,600 in the late 1970s and as a result of conservation concerns at the time, the population was protected from hunting and many of the sites supporting internationally important concentrations were given statutory protection. 

3. Under these protection measures, and helped by a series of good breeding seasons, the population increased from 17,000 in 1982/3 to 35,500 in 1998/9.  However, in the subsequent years, numbers have fallen dramatically to less than 27,000 in 2001/2, a 25% decline in 3 years.

4. Because the population is closed, and the annual population census covers all known wintering resorts, the change cannot be the result of changes in immigration or emigration, and must result from changes in birth or death rates.

5. Evidence from survival estimates based on resightings of collared individuals suggest no major changes since protection in 1982/3, supported by the results of population modelling based on counts at the two major resorts, Islay (Inner Hebrides, Scotland) and Wexford (southeast Ireland).

6. The proportion of young returning to winter at Islay and Wexford shows declining trends since protection.  Evidence from detailed observations of collared birds at Wexford shows that known aged birds are showing a delay in the age of first breeding, and that an increasingly small proportion (<5%) of all goslings surviving their first winter survive to ever breed at all.

7. Simple mathematics shows that the decline in number is simply due to the failure of the reproductive potential of the population to replace annual losses, the latter of which have not changed substantially over a period of decades.  The decline is explained by the sustained decline in reproductive output, not due to any increase in mortality, although the causes for this long-term decline remain unknown.

8. At least three potential (not necessarily mutually exclusive) explanations have been offered for the decline in reproductive success of Greenland White-fronted Geese since 1982/3.  These are increases in overall population density, reductions in summer temperatures in the north of their breeding range (a factor known to depress breeding success) and competition with Canada Geese, which have newly colonised west Greenland from northern Canada.  Other (currently unknown) factors may also be involved.

9.  Studies of interactions between the two species on the summer areas show the behavioural dominance of Canada Geese, at least during the flightless moult, which results in local displacement of White-fronted Geese.  However, more extensive survey is required to determine whether this is the major factor involved in depressing breeding success in Greenland White-fronted Geese.

10. Greenland White-fronted Geese remain a quarry species in Greenland (where a few hundred are thought killed each year because of their inaccessibility) and in Iceland, where the bag has shown a significant increase during 1995-2001.  This increase, coincident with the decline in global population size, means that the Iceland hunting kill has risen from 8% to 12% at present, and now contributes a significant, and increasing, element of overall annual mortality.

11. Whilst it is clear that the autumn hunt in Iceland was sustainable during the period of population expansion of the 1980s and 1990s, the present level of kill cannot assist in returning the population to favourable conservation status.  While the cessation of the autumn hunt there cannot halt the current decline in the overall population, it is one tangible conservation action that will contribute to the slowing of the rate of decrease in numbers.

12. It is important that the management plan, drafted and agreed for this population in Wexford, Ireland in 1992 but never formally signed by the range states (Ireland, United Kingdom, Iceland and Greenland), be reconvened and updated, to establish research and monitoring priorities for action.  Actions must be targeted to secure the population for the future to ensure that the international investment in the protection of the population that occurred in the 1980s and 1990s was not in vain.

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