Birds
Curlew
Numenius · also called curlews
A curlew finds its dinner by feel, not by sight, probing a long, downward-curved bill deep into mud until sensitive nerve endings at the tip detect a worm it could never have seen. Its rising, bubbling call over open moorland is one of the most haunting sounds in the natural world — and, for at least two curlew species, one that has now very likely gone silent for good.
Overview
Curlews, genus Numenius, are large wading birds with the longest bill, relative to body size, of any shorebird. They breed on northern grassland, moorland, and tundra, migrating long distances to winter on coastal mudflats and estuaries farther south.
Feeling for food underground
The curved bill’s tip is packed with touch-sensitive Herbst corpuscles, letting the bird detect buried worms by feel alone. Its rising, bubbling call, delivered in a rolling display flight, is one of the most evocative sounds of open wetlands — though the family has already lost ground: the Eskimo curlew and slender-billed curlew are both now feared extinct.
Status
Near Threatened and decreasing — vulnerable ground nests, agricultural disturbance, and the loss of breeding and wintering wetlands have driven serious declines across much of the family.
Curlew: common questions
Why does a curlew have such a long, curved bill?
The long, downward-curving bill lets a curlew reach and extract prey, especially earthworms and marine worms, buried significantly deeper in mud or soil than birds with shorter, straighter bills can access, giving it access to a food resource largely unavailable to many other wading birds feeding in the same habitat. The curve itself is thought to help the bird manoeuvre the sensitive bill tip around obstacles and burrow shapes underground more effectively than a perfectly straight bill would allow.
How can a curlew find worms it cannot see underground?
The tip of a curlew's bill is packed with specialised touch-sensitive receptors called Herbst corpuscles, which can detect subtle vibrations, pressure changes, and movement in the surrounding mud or soil caused by nearby prey. This effectively allows the curlew to feel its way to buried worms and other invertebrates with remarkable precision, probing the substrate methodically and adjusting its search based on what it senses through the bill rather than relying on visual detection of hidden prey.
Are any curlew species already extinct?
The Eskimo curlew, once so abundant during migration that vast flocks were shot in huge numbers by hunters in the 19th and early 20th centuries, has not been reliably confirmed for decades and is now widely considered extinct or functionally extinct. The slender-billed curlew, a separate species that bred in parts of Russia and wintered around the Mediterranean, has similarly not had a confirmed sighting in years and is also feared to be extinct, making the curlew family one of the more severely affected wading bird groups in terms of documented losses.
Why is the curlew's call considered so distinctive?
The curlew's call is a rising, liquid, almost bubbling series of notes, often given during a distinctive rolling, gliding display flight over open breeding territory, and its haunting, far-carrying quality against the backdrop of quiet moorland or wetland has made it one of the most evocative bird sounds associated with wild, open landscapes. This distinctiveness has led to the call being referenced repeatedly in regional folklore, literature, and poetry, particularly in parts of the United Kingdom and Ireland where curlews have long been a familiar, if now increasingly threatened, sound of the countryside.