Bird of the Month
How often a coastal winter train journey is made memorable by the flag-flying glimpse of a shelduck (Tadorna tadorna) along the tideline or far out on mudflats.
It is the pied plumage, exceptionally the same for male and female, which gives its name (from the Dutch sheld, ‘variegated’), although shellfish do form a large part of its diet. Shelduck are sturdy (2lbs), sedate, slow-winged birds and, although classified as a duck, are placed in bird guides among the geese.
They have none of the low-slung, streamlined and flying urgency of duck. Colloquial names, such as skeel goose, links goose and ringer goose, long ago made the association.
The predominance of white is what catches the eye. A closer view reveals the striking arrangement of broad, rust-orange, breast band, back and under-tail; bottle-green head and wing flashes (specula), black pinions, a sealing-wax scarlet bill and longish pink legs, which they stamp to expose lugworms. Perhaps it is the prominence of the Muscovy duck knob at the base of the drake’s bill which makes it seem a decorative farmyard bird out of its element.
The sheldrake lacks the poetry of a wild bird, although wild it is; and, for all its flamboyance, it has been disdained by poets and wildfowlers. Its unmusical call is a laughing ‘ag-ag-ag’ and its meat, according to the sporting naturalist Brian Vesey-fitzgerald, tastes of paint.
When a Norfolk warden was asked by a journalist the best way to cook a shelduck he thought the man was taking the mickey, so he facetiously answered in kind: place the duck in the oven alongside a brick, he told the journalist, when you can get a fork into the brick the bird will be done. His joke ‘recipe’ was duly reported as a genuine piece of country lore.
The reason why shelduck have no need for camouflage is that they nest in burrows. These burrows are usually on the shoreline, but they can be as far as six miles from water. Ducks that fail to find a burrow will sometimes lay their eggs in an existing nest. The unsuspecting hosts can find themselves parenting a double-brood of more than thirty ducklings.
Shelduck are notably communal birds. When the ducklings have left the nest, up to a hundred at a time can congregate in ‘crèches’ under the supervision of a single adult pair.
In July, most of the 180,000 British population responds to a similar instinct for safety in numbers by migrating to moult on the vast tidal flats of the Heligoland Bight, off the German North Sea coast, opposite Lincolnshire.
The strategy misfired in August 1954 when the RAF used the area for bombing practice, inadvertently killing thousands of the birds. The Air Ministry recognised its mistake and agreed not to use live ammunition during the birds’ moult period.
Shelduck begin to return in September, swelling the growing ranks of those which prefer to stay in Britain for the moult on the Wash, at Bridgwater Bay on the Severn and elsewhere.