Slender hope for the slender-bill

Richard Collins says slender-billed curlew may be Europe’s ‘Dodo’

END-OF-YEAR eco-stocktaking prompts a tale of two curlews. The past year has passed without the sighting of a bird that ornithologists hope still survives in Siberia.

A strange wader turned up at Minsmere, Suffolk, in October, 2004, which birdwatchers came from far and wide to see. Some thought it was ‘Europe’s dodo’, a slender-billed curlew, but others disagreed. The argument became so heated that it made the columns of the London Times. It’s just about possible that a slender-billed visited Minsmere but the visitor was probably a slightly odd-looking, but ordinary, Eurasian curlew.

The confusion at Minsmere is understandable. Slender-billed and Eurasian curlews are difficult to separate in the field. They have similar plumage, although the slender-billed is whiter on the tail and under the wings, and, as the name implies, its bill is thinner than that of the common species. The definitive ‘field marks’, however, are heart-shaped spots on the flanks, which can only be seen at close range. The slender-billed is smaller, about the size of a whimbrel, a member of the curlew family which passes through Britain and Ireland in spring and autumn.

The slender-billed visited northern Europe very occasionally, but, apart from the doubtful Minsmere claim, it has never been seen in Britain.

The bird’s breeding range is, or perhaps was, the taiga, extending from the Urals to the valley of the Ob. Few nests have ever been found and little is known of the slender-billed’s breeding habits. The remoteness of its summer haunts may be a factor in the slender-billed’s downfall. Creatures which don’t encounter humans when young seldom fear people. People are thin on the ground in Siberia, and, when this confiding bird travelled to the Mediterranean in autumn, it was an easy target for hunters. Being fairly large and plump, it was much in demand for the table. Up to a century ago, the slender-billed was still fairly common in southern European and North African wetlands. Then, hunting pressure drove it to the verge of extinction.

No slender-billed has ever been seen in Ireland. However, an American curlew with a similar history visited us once. In 1900, Richard Ussher and Robert Warren wrote about a carcass found in a Dublin poulterer’s shop in October, 1870. ‘It remained until the 28th of that month, exposed for sale. It was then purchased for sixpence, so that its rarity was not suspected by the seller’. The bird, which had been shot in Co Sligo, turned out to be an Eskimo curlew. The specimen is now in the Natural History Museum.

The Eskimo curlew bred in Canada and Alaska and migrated as far south as Argentina each autumn. Like its slender-billed cousin, it was good to eat and easily shot. The migration pattern was unusual. On its southward journey, it travelled along the coast and over the sea, avoiding hunters. In spring, however, it returned northwards overland and was slaughtered. About two million were killed each year in the late 19th century and no large flocks were recorded after 1870. Hunting was prohibited throughout its migration route from 1916. It was too little too late; by 1926, the Eskimo curlew was believed to be extinct. As with its slender-billed cousin, claims of sightings are made from time to time. Most have been dismissed but, in 1959, one definitely turned up on the coast of Texas. Another was photographed there in 1962 and a record from Massachusetts in August, 1972 was accepted by the American Ornithologists Union.

There were eight curlew species in the world at the beginning of the 20th century. Thanks to greed and stupidity, it seems that only six remain. Two of them are familiar Irish birds. The numbers of our much-loved Eurasian curlew, with its beautiful, bubbling song and evocative call, seem to be static. This conservative bird is a creature of habit; it moves each year between a summer breeding territory inland and a winter feeding territory on the coast.

In contrast, our other curlew, the whimbrel, is one of the world’s great migrants, with a lifestyle very similar to its slender-billed and Alaskan cousins. However, this adventurous bird, found on both sides of the Atlantic, seems to be holding its own; the distinctive piping call of the ‘May bird’ was heard, as usual, along the Irish coast in 2008.