Barnacle Goose: The Bird Once Thought to Grow on Trees

Each major claim carries one of three labels. established means supported by primary records, official bodies or several independent reliable sources. shared means the core fact is sound but sources disagree on details, dates or interpretation. traditional means widely repeated but not traceable to a primary or independent source.

Population counts are carried out annually by the Wildfowl & Wetlands Trust and others and vary from year to year, so this card gives no current totals. The historical figures it does give are dated, and most come from Malcolm Ogilvie's account in the Scottish Ornithologists' Club's The Birds of Scotland (2007).

The goose

established The barnacle goose is a small, neat goose with a creamy white face, black crown, neck and breast, and silvery grey back barred with black and white. It breeds on Arctic cliffs and tundra, where goslings famously leap from cliff ledges soon after hatching. It winters in large flocks on coastal grasslands.

The barnacle legend

established Because no one in Britain had seen barnacle geese nest, medieval writers explained their appearance by claiming they grew from goose barnacles, shellfish whose feathery feeding limbs resemble plumage, attached to driftwood, or even from trees growing by the sea. Gerald of Wales described the belief in the twelfth century, and the Scottish historian Hector Boece repeated it in 1527. Some churchmen argued that as the geese were not born of flesh they could be eaten on fast days, though Pope Innocent III forbade this in 1215.

established Mark Cocker and Richard Mabey, in Birds Britannica (2005), trace the story's prominence to Gerald's Topographia Hibernica of 1186. Gerald claimed he had "frequently seen, with my own eyes" more than a thousand of the birds hanging from a single piece of timber. Later scholars were taken in too. William Turner, often called Britain's first ornithologist, accepted it, and the herbalist John Gerard went further, claiming to have watched the birds emerge from their shells himself. Not everyone was fooled: the Emperor Frederick II doubted the tale in the thirteenth century and sent envoys north to investigate. The book says the myth lasted about 500 years and only finally died in the early twentieth century. The name "barnacle", shared by the goose and the goose barnacle, is its main surviving trace.

established The Lenten loophole lingered in practice long after the belief faded. Birds Britannica reports that people in County Kerry were said to hold to the old tradition into the twentieth century, which conveniently let them eat goose in Lent, and that they also called the brent goose a "barnacle" so it could be eaten too.

Scotland's wintering flocks

established Barnacle geese breeding in Greenland winter mainly on Islay and other Hebridean islands, where large numbers feed on farmland. Those breeding in Svalbard winter almost entirely on the Solway Firth, where the Wildfowl & Wetlands Trust reserve at Caerlaverock provides protection.

established Three populations. The Scottish Ornithologists' Club's The Birds of Scotland (2007), in an account by Malcolm Ogilvie, describes three separate breeding populations, in north-east Greenland, Svalbard and arctic Russia. All the Greenland and Svalbard birds winter in Britain and Ireland; the Russian population, much the largest at about 350,000, winters along North Sea coasts from Belgium to Denmark. At the time of writing about 45,000 Greenland birds and 25,000 Svalbard birds wintered in Scotland, just under 20% of the world population. Scotland held about 80% of the Greenland population, the rest wintering in western Ireland, and at times all of the Svalbard population.

established The Greenland geese. Their winter range is almost entirely on islands, from South Walls in Orkney along the north coast and through the Outer and Inner Hebrides to Islay. Many are small, uninhabited islands grazed by sheep, such as the Monachs, the Shiants and the Treshnish Isles. Eleven aerial surveys between 1959 and 2003 found geese at 20–42 sites in any one year and about 100 in all. Where summer sheep grazing has stopped, some islands have become unsuitable. Islay holds about 75% of the Scottish total, with five main feeding ranges each linked to a night roost, chiefly at the heads of Loch Gruinart and Loch Indaal. The main arrival is in the first ten days of October and the birds leave in mid-April. Ogilvie links the population's growth to Islay's farming changes since the 1950s, from better grass mixtures to silage and heavier fertiliser use, which leave the geese in better condition for the flight north.

established The Svalbard geese. These geese cross the North Sea in late September, usually making landfall between Lothian and Northumberland, and then cross northern England to the Solway. On the Scottish side they winter from Mersehead to about Cummertrees, including Kirkconnell Merse on the Nith. From the 1960s to the 1980s Caerlaverock and its surrounds held up to the whole population; now the RSPB's Mersehead reserve and Caerlaverock can each hold up to 40%. Before the population grew, almost all the geese stayed on the Scottish side until shooting ended in late February.

The rood goose of the Solway

established In south-west Scotland the barnacle goose has an old local name: the rood goose. Birds Britannica links it to Dumfries's traditional Rood Fair, a holiday in the first week of October, which coincides with the geese's arrival from the Arctic. The book describes Caerlaverock, just down the road from Dumfries, as the most important barnacle goose site on the Solway, where as much as one-third of the entire Svalbard population can be seen in a couple of fields. In the early 2000s that population numbered about 27,000 birds, almost wholly dependent on this one estuary.

established Islay's geese have long been a source of friction. In the mid-1990s the island held about 30,000 wintering barnacle geese and 15,000 Greenland white-fronted geese, and farmers complained of damage to grazing. According to the book, management payments from Scottish Natural Heritage had largely calmed the dispute by the time of writing, though the argument has since resurfaced as numbers and policies have changed.

A conservation story

established Hunting and disturbance reduced the Svalbard population to a few hundred birds by the mid-twentieth century. Protection and reserves helped it recover to tens of thousands. In 2021–22, avian influenza killed a substantial proportion of the Solway population. On Islay, the geese damage grassland, and schemes to compensate farmers and to manage numbers have been controversial.

established An old wintering bird. Ogilvie notes that the present wintering areas have been occupied since the earliest written records, with Orkney especially mentioned. In the nineteenth century the geese were "very common in the West of Scotland, and especially abundant in the Outer Hebrides", and there were thousands on Islay, Jura, Colonsay and the Treshnish Isles, where they already caused severe crop damage. Up to 10,000 wintered on the Solway in the late nineteenth century. Wartime disturbance and uncontrolled shooting then brought the Svalbard population down to about 300 birds in the winter of 1948/49.

established Protection in stages. The Protection of Birds Act 1954 gave the barnacle goose full protection on the Scottish mainland for the first time, but kept a two-month shooting season on islands west of 5° W, which took in almost all the Hebrides. Islay landowners took a few hundred a year until numbers rose in the 1970s; by 1980 about 1,500 were being shot each year and wintering numbers fell sharply. The Wildlife and Countryside Act 1981 then gave full protection. For the Svalbard birds, protection in the UK (1954) and Svalbard (1955) was followed by Caerlaverock National Nature Reserve (1957), the Wildfowl Trust reserve (1970), breeding sanctuaries in Svalbard (1973) and Mersehead (1990s). Numbers passed 5,000 in 1973/74, 10,000 in 1984/85 and 15,000 in 1994/95, and held at a record 27,000 from 2002/03 to 2004/05. The book's conservation chapter, by Paul Walton and Stuart Housden, calls the 1954 legislation some of the most effective in Scotland's history.

established The goose debate. The same chapter records that the conflict with farmers grew increasingly bitter in the 1990s, leading to a National Goose Forum and local goose management schemes with dedicated feeding areas and co-ordinated scaring. In the 1980s the government began licensing the shooting of barnacle geese on Islay, including within Special Protection Areas. The RSPB challenged this and won on appeal in the Court of Session in July 2000, though licensed shooting was still allowed provided it did not threaten the long-term viability of the local populations.

established Feral birds. Small numbers of free-flying feral barnacle geese now live in Scotland and have bred in at least eight recording areas since 1990. On Colonsay, barnacle geese have nested in mixed pairs with Canada geese on cliff sites; Ogilvie suggests these may be wild birds injured by shot.

• People once believed barnacle geese grew from shellfish or trees.
• Hector Boece repeated the belief in 1527.
• Barnacle goose goslings leap from cliffs soon after hatching.
• Svalbard geese winter on the Solway.
• Greenland geese winter on Islay.
• In Dumfriesshire the bird was called the "rood goose", after the Rood Fair held in Dumfries in early October, when the geese arrive.
• Gerald of Wales claimed to have seen more than a thousand baby geese hanging from one piece of driftwood.
• Up to a third of the entire Svalbard population can gather in a couple of fields at Caerlaverock; The Birds of Scotland (2007) puts the maximum at about 40%.
• Only about 300 Svalbard barnacle geese were left in the winter of 1948/49.
• Scotland held just under a fifth of the world's barnacle geese in 2007.
• Islay alone held about three-quarters of the Greenland geese wintering in Scotland.

• Do not give precise population figures without a current source; the Islay (mid-1990s), Svalbard (early 2000s) and 2007 figures in this card are historical and dated.
• Do not say Caerlaverock alone holds the Svalbard population; since the 1990s Mersehead has held a similar share.
• Do not credit Hector Boece with originating the legend; it was already centuries old when he wrote, and Gerald of Wales gave it prominence in 1186.