FOULA HERITAGE
Foula - The Edge of the World
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FOULA HERITAGE
Foula - The Edge of the World
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Foula 1924-37 Telegraph Installation Foula 1936 The Edge of the World
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THE GREAT SKUA OR BONXIE
The Great Skua (Catharacta skua skua) is a member of the Skua family Stercorariidae, which is closely related to the Gull family Laridae. In Foula the Great Skua is known as the Bonxie. A name thought to have come from the Norse Bunksi, meaning an untidy old woman. Bonxies differ from Gulls in being a dark brown colour, often flecked with a lighter yellowish brown. Like the gulls they have webbed feet but their toes have strong hooked claws, rather like those of a bird of prey. Their bills are thicker, stronger and more hooked. The wings being broader and more rounded than those of a gull and having conspicuous white patches across the base of the primary feathers. Some individuals have a few white feathers, mostly on the head.
The Bonxie is thought to be a very new bird species in evolutionary terms. No evidence has yet been found that the Bonxie has existed as a species for more than the last 500 years. It is a bird of the Northern Hemisphere, its closest relatives are the Antarctic Skuas and it is thought to be a descendent of one of them, or perhaps to be a hybrid of two of them. Somehow, sometime, a pair of one of the Antarctic Skuas got lost in the North Atlantic and settled, probably in Iceland. From where, in time, their progeny spread to Faroe and then on to Shetland. The first record of Bonxies being in Shetland dates from 1774 when George Low found three pairs in Unst and six or seven pairs in Foula. He reported: “In Foula this is a privileged bird, no man will nor dare shoot it under the penalty of 16s. 8d. Ster., nor destroy its eggs; when they meet it at sea, whatever fish they have in the boat Skua always gets a share, and all this out of gratitude for beating off the Eagle, who dares not venture to prey on the island during the whole breeding season.” A later visitor, Richard Drosier, in 1828, describes Bonxies attacking an eagle: “As I was intently observing the majestic flight of the eagle, on a sudden he altered his direction, and descended hurriedly, as if in the act of pouncing; in a moment, five or six of the skua passed over my head with an astonishing rapidity; their wings partly closed and perfectly steady, without the slightest waver or irregularity. They appeared, when cleaving the air, like small fragments of broken rock, torn and tossed by a hurricane from the summit of a towering cliff, until, losing the power that supported them, they fell prone to the sea beneath. The skuas soon came up with him, as their descent was very rapid, and a desperate engagement ensued. The short bark of the eagle was clearly discernible above the scarcely distinguished cry of the skua, who never ventured to attack his enemy in front; but, taking a short circle around him, until his head and tail were in a direct line, the skua made a desperate sweep or stoop, and, striking the eagle on the back, he darted up again almost perpendicular; when, falling in to the rear, he resumed his cowardly attack. Three or four of these birds, thus passing in quick succession, invariably succeed in harassing the eagle most unmercifully. If, however, he turns his head previously to the bird’s striking, the skua quickly ascends, without touching him. This engagement continued some time, the eagle wheeling and turning as quickly as his ponderous wings would allow; until I lost the combatants in the rocks. As soon as this is the case, the skuas leave, and quickly return to the mountain.” Drosier and other 19th century ornithologists visited Foula for the purpose of shooting the Bonxie for their collections. Probably because of the island’s isolation the Bonxies were never shot out as they were in Unst. The population went up and down from a low point of three pairs to as many sixty. In the latter half of the 19th century the lairds of Foula, the Scotts, did their best to protect the birds. To mark this the Zoological Society of London presented them with the large silver medal of the Society, round which was inscribed, “For many years’ protection of the Great Skua in Foula, by Robert T. C. Scott, 1891.” In the first half of the 20th century as the Bonxie population began to expand the islanders took eggs from their first layings for food. If their first eggs are lost Bonxies will relay twice. Unlike most other seabirds Bonxies nest on the open moorland – a much easier place for the islanders to obtain eggs compared to climbing in Foula’s cliffs. The nests are mere scrapings in the vegetation. Beginning in 1956 the Brathay Exploration Group, from Ambleside in Cumbria, began a programme of ringing and observing Foula’s Bonxies. A member of one of their parties of young people in 1971 was Bob Furness. This visit began Bob’s interest in Foula’s bird life and in particular his involvement with its Bonxies. From 1973 to 1977 he spent four months every year in Foula. Bob wandering through the island’s extensive Bonxie territories, notebook in hand, became a very familiar sight indeed. Bob, now a Professor, stayed on at Glasgow University and is still overseeing that university’s students’ bird studies in Foula. In 1987 Bob completed a book The Skuas, detailing the life and times of the world’s four Northern Hemisphere skuas and its five Southern Hemisphere ones. Rather inevitably given Bob’s, and his students’, long association with the Isle, Foula’s Great and Arctic Skuas feature prominently. The records show that the colony had an almost constant growth of 7% annually from 1900 to 1975, when population reached its peak with 3,000 pairs and about 4,000 non breeders. By this time their nesting territory had expanded to cover much of the island. At the beginning of the century there was only one Bonxie club, where non breeding birds gathered to loaf and socialise. This was a mound on the ridge between the summits of the Kame and the Sneug. By the early 1970s there were thirteen clubs, four of them associated with lochs where the Bonxies bathe. Both off duty breeding birds and non breeders love to bathe in fresh water. The 20th century saw a big expansion not just in Bonxie numbers but in the number of colonies. By 1985 there were about thirty new colonies in Scotland and ten further north, either in Norway or the Arctic islands. All of these have had some colour-ringed birds from Foula present in their founding years. Ringing returns have shown where the Bonxies move to in the years before they begin to return to their breeding places. First winter birds migrate to around the Iberian Peninsular, west to the Azores and south to the Cape Verde islands. Their following summer they move north to an area from the Bay of Biscay to Spitzbergen and west to the seas around Iceland, southern Greenland and Newfoundland. The next winter they are found from the western coast of Italy to the Bay of Biscay and south to off Liberia and across the Atlantic to the northern coast of Brazil and west into the eastern Caribbean Sea. In their third summer they will start returning to where they were born. By the time they first breed at five to eight years old their winters will be spent in southern British waters, the Bay of Biscay and around the Iberian peninsular.
The Bonxie is a very aggressive bird. George Low gives a good description of how it defends its nesting territory : “Never man had better reason to observe or to remember the natural history of Bonxie than I at this time. I no sooner approached his quarters but he attacked me and my company with so great fury that every one of us were forced to do him obeyance for every stroke. He beat my water Spaniel quite out of the pit, insomuch that he fled to our feet for shelter, and could not be forced out again, tho' a bold dog and well used to encounter Otters, or what else might be lamed by a gun. But tho’ Bonxie seemed to preserve some regard for us while we kept together, upon him he had no mercy, every whip he gave him made his wings crack, and the dog crouch into the hollows of the moor till we came up and relieved him.”
Some of the Bonxies’ feeding habits are no less aggressive. Fledgling Kittiwakes, Guillemots and Arctic Skuas are attacked and killed. Adult puffins are held underwater and drowned. Over four years one pair of Bonxies killed most of a colony of Black Guillemots by standing on the boulders above their nests and pouncing on them when they emerged. Mercifully for Foula’s seabirds the preferred diet of Foula’s Bonxies is Sandeels or discarded fish from fishing boats. Often the Sandeels are driven to the sea surface by predatory fish. Here they form into a dense ball, making it easy for the Bonxies to eat their fill. Worryingly for those who love and admire Foula’s seabirds all is not well in the oceanic food chain. The sea has warmed and the bed rock of the food chain, plankton, has moved further north. Sandeels are in short supply, fishing boats are discarding fewer fish. Recently there have been years in which few Bonxie chicks have hatched and none have fledged. Naturally other species are suffering too and should the Bonxies turn to the wholesale eating of other seabirds the outlook is grim. Low, George. 1879. A tour through the islands of Orkney and Shetland containing hints relative to their ancient, modern and natural history collected in 1774. Kirkwall: William Peace & Son. 2nd Edition: 1978. Melven Press, Inverness. Drosier, Richard. Account of an ornithological visit to the islands of Shetland and Orkney in the summer of 1828. Mag. Nat. Hist. 1830, 321-326; 1831, 193-199. Furness, R.W. 1987. The Skuas, T & A.D. Poyser, Calton. ISBN 0-85661-046-1
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