Bird of the Month: Oystercatcher

Oysters are not the preference of the oystercatcher ( Haematopus ostralegus). But its sturdy, orange bill makes short work of almost anything else edible on the foreshore.

Colin Tudge ( The Secret Life of Birds) likens this formidable implement to a Swiss army knife: ‘It’s a probe for prising molluscs out of the mud. It’s a crowbar, for levering the shells of bivalve molluscs apart – or for flicking limpets off their rocks. It’s a pair of kitchen scissors, for slicing through the adductor muscle that keeps the bivalve shells together. It’s a hammer, for peremptorily smashing the shells of molluscs that refuse to cooperate.’

An oystercatcher can eat a cockle every 72 seconds and a daily weight of nearly 1 lb of meat (500 shells plus).

Its old name is more accurate: the sea pie, as in magpie; the dramatic, black and white plumage, offset by the carrot bill and pink legs. Thomas Southwell, in a 1902 footnote to the 17th-century Sir Thomas Browne’s pioneering book, Notes and Letters on the Natural History of Norfolk, wrote, ‘It breeds occasionally about Wells, where it is universally known as the “Dickey-bird”.’

As with many of our resident birds, its winter population is doubled – to more than 300,000 – by continental migrants seeking milder weather. These roam in flocks but, for most of us, oystercatchers are a seaside-holiday pleasure.

On the nine-hole links at Girvan, in Ayrshire, my golfing partner hooked his drive out to sea, where the ball hit a submerged rock and rebounded on to the fairway. Two oystercatchers were unmoved by this startling event as they stood in twin tidal pools (‘They are stupidly trusting birds’ – ‘B B’, Tide’s Ending), a breath of wind blurring one reflection into bright abstraction, while the other remained glassy true to the bold original. Summer days.

In Britain, it breeds inland on river shores, the more unfrequented – and therefore usually northern – the better, its eggs blending with the shingle.

‘On the Dee’s shingle, one swooped at me like a skua; and the piping! – shrillness lancing the brain cells. Yet you’re handsome, too. Black and white as your nature. And that iris – pure ruby. Quickstepping along in your early pairs in the spring on the beaches, heads down, beaks splayed wide, kleeping like crazy! The eggs like big pebbles in a scrape on the shingle, or in fresh-seeded barley or turf. One I knew, in the hollowed top of a big fence post, beside the Candy Burn. Three eggs on wood chippings; the bird brooding on its fence-post high-rise… The leap of these three fluff-balls – so light it’s their only defence – into space’ – Gerry Cambridge, from Haematopus ostralegus, in his prose-poetry collection Aves.

In Aberdeen, the synthetic beaches offered by the gravel-covered roofs of the Royal Infirmary were soon colonised by the birds to the extent (including other similar roofs) of 250 pairs.

If buildings offer this amenity, they will be colonised, as is the case with other newly exploited habitats – Midland gravel pits, and even the rotten fence post cited by Cambridge.