Origin of Lesser White-fronted Geese causes debate
Lesser White-fronted Geese in Gloucestershire, Kent and Yorkshire have been drawing crowds this winter, but the odds are against them being considered wild birds by the records committees.
One arrived at Oare Marshes, Kent, on 15 December 2023. Aged as an adult by its white forehead, dark belly markings and square-tipped upperpart feathers, it went on to commute between the reserve and Shellness, on the Isle of Sheppey.
Another adult Lesser White-fronted Goose turned up at Adwick Washlands RSPB, South Yorkshire, on 19 January.
These reports follow sightings of an adult at the species' former British hot-spot at Slimbridge, Gloucestershire, since October 2023. This is considered likely to have been the same escaped bird noted with Canada Geese in Wiltshire almost a month beforehand.
Like the Yorkshire bird, the Lesser White-fronted Goose in Kent has been consistently in the company of Greylags (Alex Perry).
Although the most recent birds are unringed and fully winged, their association with naturalised Greylag Geese instantly dampens their chances when it comes to assessment by the British Birds Rarities Committee (BBRC). Being adults is not against them, as young geese usually accompany experienced parents on their first migration and vagrancy of adult geese has long been accepted, with lone older birds routinely getting caught up in migrating flocks of other species and solid proof of the phenomenon through ring-reading.
With multiple escaped Lesser White-fronts known to be present in Britain for a number of years, realistic candidates for acceptance as wild birds are likely to be those tied to flocks of expected carrier species. In the past, apparently wild individuals have arrived with flocks of Russian White-fronted Geese and Taiga Bean Geese. These birds will have migrated from areas where wild Lesser White-fronted Geese, or those from reintroduction projects in Fennoscandia, could have joined them and continued to Britain in their company.
A well-known adult already assessed by BBRC and placed on Category E (which houses records of apparent escapes) followed Pink-footed Geese between Yorkshire, Lancashire and Norfolk between 2019 and March 2023.
While Pink-feet bound for Iceland and Greenland are not the most inspiring carrier species for wild Lesser White-fronted Geese, BBRC has accepted individuals travelling with this species before. It was the fact that the individual oversummered with naturalised Greylags in Yorkshire that doomed it to Category E.
Poor winter for wild geese
Not helping the case of the most recent Lesser White-fronts, winter 2023-24 has been a generally disappointing one for wild geese, with no fierce cold snaps driving herds from the Continent. Numbers of Russian White-fronted Geese have been unremarkable across the board and Tundra Bean Goose has been stubbornly scarce, while Taiga Beans continue their steady decline on the two traditional wintering grounds. Only two Taigas made a brief appearance in east Norfolk in December, where the formerly significant Yare Valley population hosted a Lesser White-fronted Goose in the winters of 2010-11 and 2011-12.
Once a regular tag-along with Russian White-fronted Geese in Britain and the near-Continent, records of acceptable Lesser White-fronts have sharply declined. The species was a frequent fixture with the large flocks of Russian White-fronts at Slimbridge until the late 1990s. However, only five apparently wild birds are on the national record books for this century, the most recent being a first-winter at Burgh-by-Sands, Cumbria, with Pink-footed Geese on 8 January 2019.
In the company of naturalised geese in a largely mild winter, it is unlikely that any of the current birds, all still present in late January, will convince BBRC that they are of wild origin.