Eurasian curlew

The Eurasian curlew or common curlew (Numenius arquata) is a very large wader in the family Scolopacidae. It is one of the most widespread of the curlews, breeding across temperate Europe and Asia. In Europe, this species is often referred to just as the "curlew", and in Scotland known as the "whaup" in Scots.

Taxonomy

The Eurasian curlew was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Scolopax arquata.<ref>Template:Cite book</ref> It is now placed with eight other curlews in the genus Numenius that was introduced by the French ornithologist Mathurin Jacques Brisson in 1760.<ref>Template:Cite book</ref><ref name=ioc>Template:Cite web</ref> The genus name Numenius is from Ancient Greek Template:Lang, Template:Lang, a bird mentioned by Hesychius. It is associated with the curlew because it appears to be derived from neos, "new" and mene "moon", referring to the crescent-shaped bill. The species name arquata is the Medieval Latin name for this bird, derived from Latin Template:Lang, "bow-shaped", and again referring to the shape of the bill.<ref name=job>Template:Cite book</ref>

The English name "curlew" is imitative of the Eurasian curlew's call, but may have been influenced by the Old French Template:Lang, "messenger", from Template:Lang, "to run". It was first recorded in 1377 in Langland's Piers Plowman "Template:Lang".<ref name=OED>Template:Cite OED</ref>

Three subspecies are recognised:<ref name=ioc/>

• N. a. arquata, (Linnaeus, 1758) – breeds in west, north and central Europe
• N. a. orientalis, Brehm – 1831 – breeds in west and central Siberia through to Northeast China
• N. a. suschkini, Neumann, 1929 – breeds from western Kazakhstan to southwestern Siberia

Description

The Eurasian curlew is the largest wader in its range, at Template:Convert in length, with an Template:Convert wingspan and a body weight of Template:Convert.<ref name=CRC/> It is mainly greyish brown, with a white back, greyish-blue legs and a very long curved bill. Males and females look identical, but the bill is longest in the adult female. It is generally not possible to recognize the sex of a single Eurasian curlew, or even several ones, as there is much variation; telling male and female of a mated pair apart is usually possible however. The familiar call is a loud curloo-oo.

The only similar species over most of the curlew's range is the Eurasian whimbrel (Numenius phaeopus). The whimbrel is smaller and has a shorter bill with a kink rather than a smooth curve. Flying curlews may also resemble bar-tailed godwits (Limosa lapponica) in their winter plumages; however, the latter have a smaller body, a slightly upturned beak, and legs that do not reach far beyond their tail tips. The Eurasian curlew's feet are longer, forming a conspicuous "point".

Distribution and habitat

The curlew exists as a migratory species over most of its range, wintering in Africa, southern Europe and south Asia. Occasionally a vagrant individual reaches places far from its normal range, such as Nova Scotia<ref name=NHMNS/> and the Marianas.<ref name=Wiles2000/><ref name=Wiles2004/> It is present all year in the milder climates of Ireland and the United Kingdom and its adjacent European coasts.

Reclamation and drainage of marshy fields and moorland, and afforestation of the latter, have led to local decreases, while conversion of forest to grassland in some parts of Scandinavia has led to increases there.<ref>Encyclopedia of the Animal World (1977): Vol.6: 518–519. Bay Books, Sydney.</ref>

Behaviour and ecology

The Eurasian curlew is generally wary. It is highly gregarious outside the breeding season.

Breeding

The nest is a bare scrape in meadow or similar habitats. The clutch size of the curlew consists of four eggs which are laid in April or May, and both adults incubate them for four weeks until they begin to hatch. It has been observed that curlews tend to nest close to common kestrels' nests, as they can offer protection from other predators, such as corvids, even though kestrels also prey on curlew nests.<ref>Norrdahl, K., Suhonen, J., Hemminki, O. et al. Oecologia (1995) 101: 105. https://doi.org/10.1007/BF00328906</ref>

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  Clutch of eggs
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  Eggs Museum Wiesbaden, Germany
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  In flight, Argyll, Scotland
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  Skull

Food and feeding

The Eurasian curlew feeds by probing soft mud for small invertebrates, but will also pick small crabs and earthworms from the surface if the opportunity arises.

Predation

Eurasian curlews eggs are preyed on by foxes and predatory birds.<ref>Template:Cite web</ref> In addition sheep have been recorded by the BBC nature series Springwatch preying on the eggs.<ref>Template:Cite web</ref><ref>Template:Cite web</ref>

Status

The Eurasian curlew was formerly listed as a species of Least Concern by the IUCN, owing to its expansive range and relatively large population. However, the population of the Eurasian curlew was noticed to be declining at a very rapid rate. Following the evaluation of its population trend, the classification was found to be outdated, and it was consequently promoted to Near Threatened status in 2008. Though it is a common bird, its numbers are noticeably declining,<ref name="iucn status 11 November 2021"/> particularly in the United Kingdom and Ireland, which have about a quarter of the global population. In the twenty years up to 2016, the population is estimated to have declined by more than 50% in England and Scotland, more than 80% in Wales, and more than 90% in Ireland. At the end of 2015 it was placed on the United Kingdom's red list of most endangered bird species.<ref>Template:Cite news</ref> The curlew is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.<ref>Template:Cite web</ref>

Research by scientists at the British Trust for Ornithology suggests that curlew populations in the UK have been negatively affected in areas with high levels of arable farming and afforestation which have reduced its natural habitats of open grasslands.<ref>Template:Cite journal</ref>

External links

• Conserving breeding curlews in Southern England
• (Eurasian) curlew species text in The Atlas of Southern African Birds
• Video of a Curlew Probing the Mud in the Thames Estuary
• Template:Avibase
• Template:EBirdSpecies
• Template:VIREO
• Template:IUCN Map
• Template:Xeno-canto species
• Template:Field guide birds of the world