| Water pipit | |
|---|---|
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| Anthus spinoletta spinoletta | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Motacillidae |
| Genus: | Anthus |
| Species: | A. spinoletta |
| Binomial name | |
| Anthus spinoletta | |
 | |
| Range ofA. spinoletta Breeding Resident Passage Non-breeding | |
| Synonyms | |
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Thewater pipit (Anthus spinoletta) is a smallpasserine bird which breeds in the mountains ofSouthern Europe and thePalearctic eastwards toChina. It is a short-distancemigrant; many birds move to lower altitudes or wet open lowlands in winter.
The water pipit inbreeding plumage has greyish-brown upperparts, weakly streaked with darker brown, and pale pink-buff underparts fading to whitish on the lower belly. The head is grey with a broad whitesupercilium ("eyebrow"), and the outer tail feathers are white. In winter, the head is grey-brown, the supercilium is duller, the upperparts are more streaked, and the underparts are white, streaked lightly with brown on the breast and flanks. There are only minor differences among the threesubspecies, the sexes arealmost identical, and young birds resemble adults. The water pipit's song is delivered from a perch or in flight, and consists of four or five blocks, each consisting of about six repetitions of a different short note.
Water pipits construct a cup-like nest on the ground under vegetation or in cliff crevices and lay four to six speckled grey-ish white eggs, which hatch in about two weeks with a further 14–15 days tofledging. Although pipits occasionally catch insects in flight, they feed mainly on smallinvertebrates picked off the ground or vegetation, and also some plant material.
The water pipit may be hunted bybirds of prey, infested by parasites such asfleas, or act as aninvoluntary host to thecommon cuckoo, but overall its population is large and stable, and it is therefore evaluated as aspecies of least concern by theInternational Union for Conservation of Nature (IUCN).
The familyMotacillidae consists of thewagtails,pipits andlongclaws. The largest of the three groups is the pipits,genusAnthus, which are typically brown-plumaged terrestrialinsectivores. Their similar appearances have led totaxonomic problems; the water pipit and thebuff-bellied pipit were both formerly consideredsubspecies of theEuropean rock pipit.[2] Of these, the rock pipit is the more closely related to the water pipit, based on external and molecular characteristics.[3][4] Other near relatives are themeadow,red-throated androsy pipits.[4][5]
The water pipit was first described byCarl Linnaeus in the tenth edition of hisSystema Naturae in 1758 asAlauda spinoletta (characterised asA. rectricibus fuscis : extimis duabus oblique dimidiato-albis).[6] The current genusAnthus was created for the pipits by German naturalistJohann Matthäus Bechstein in 1805.[7]Anthus is theLatin name for a small bird of grasslands, and the specificspinoletta is a local dialect word for a pipit from theFlorence area of Italy.[8]
There are three recognised subspecies of the water pipit:
A possible fourth race from the northwestern Caucasus,Anthus spinoletta caucasicus, cannot be reliably separated fromA.s. coutellii. The latter form is itself a potential new species, based ongenetic data, appearance and a characteristicflight call.[5]
The water pipit is 15–17 centimetres (5.9–6.7 in) long and weighs 18.7–23 grams (0.66–0.81 oz). The adult of the nominate race in spring plumage has greyish-brown upperparts, weakly streaked with darker brown, and pale pink-buff underparts fading to whitish on the lower belly. There may be some faint streaking on the breast and flanks. The head is grey with a broad whitesupercilium. The outer tail feathers are white, and the legs, bill and iris are dark brown or blackish. In non-breeding plumage, the head is grey-brown and the supercilium is less distinct. The upperparts are more streaked, and the underparts are white, marked lightly with brown on the breast and flanks.[3][5]
The sexes are similar although the female has, on average, a greyer head. Young birds resembles the non-breeding adult, but are browner and more streaked above with prominent streaking on the underparts.A. s. coutellii is smaller than the nominate subspecies and the white of the outer tail feathers has a hint of grey. It is paler and more heavily streaked above, and in summer plumage the underparts' colour covers a larger area and has a rusty tint.A. s. blakistoni is large, pale and less strongly streaked.[5]
The water pipit has a completemoult between July and September, although there is considerable individual variation in timing. There is a partial pre-breeding moult, mainly between January and March, but with much variability in timing. This moult typically involves replacing the head, body and some wing feathers, but the extent is again variable. Very occasionally, females may moult into what looks like non-breeding plumage, rather than the expected brighter garb. The chicks start to gain juvenile plumage as soon as a month after hatching, and most have completed the transition to near-adult appearance by September. The first pre-breeding moult is similar to that of the adult, but may be less complete or even absent.[10]
The water pipit is closely related to the Eurasian rock pipit and the meadow pipit,[4] and is rather similar to both in appearance. Compared to the meadow pipit, the water pipit is longer-winged and longer-tailed than its relative, and has much paler underparts. It has dark, rather than pinkish-red, legs. The water pipit in winter plumage is also confusable with the Eurasian rock pipit, but has a strong supercilium, greyer upperparts, and white, not grey, outer tail feathers; it is also typically much warier.[11] The habitats used by European rock and water pipits are completely separate in the breeding season, and there is little overlap even when birds are not nesting. There is also little mixing with breeding meadow pipits, although since 1960 some overlapping territories have been found where the species coexist.[5]
The European rock pipit's subspeciesAnthus petrosus littoralis in summer plumage is particularly close in outward appearance to the water pipit. The rock pipit normally has a bluer tint to the head, streaking on the breast and flanks, and buff outer tail feathers,[11] and the songs are also different.[5][12] The species mostly occupy differenthabitat types even when they occur in the same general area.[13]
The water pipit's song is delivered from a perch or in flight, and consists of four or five blocks, each consisting of about half a dozen repetitions of a different short note.[5] In comparison, the European rock pipit's song is a sequence of about twenty tinklingcheepa notes followed by a rising series of thingee calls, and finishing with a shorttrill.[12] The call of the water pipit is a single or double sharp "dzip" or similar, slightly harsher than softsip sip sip of the meadow pipit or the shrillpseep of the European rock pipit. The short, thinfist flight call is intermediate between thesip of the meadow pipit and the rock pipit'sfeest.[5][11] The differences between the calls of the pipit species are very subtle, and not diagnostic in the absence of other evidence.[11] The flight call of the subspeciesA. s. coutellii is shorter and more buzzing than that of the nominate race.[5]
The breeding range of the water pipit is the mountains of southern Europe and Asia from Spain to central China, along with theMediterranean islands of Sardinia and Corsica.[5][9]
The water pipit is predominantly a mountain species in the breeding season, found inalpine pasture and highmeadows with short grass and some bushes or rocks. It is typically found close to wetter areas and often on slopes. It breeds between 615–3,200 metres (2,020–10,500 ft) altitude, mostly 1,400–2,500 metres (4,600–8,200 ft). Itmigrates relatively short distances in autumn to lower ground, typically wintering on coastal wetlands,marshes, rice fields and similar habitats. Although most birds move to lowlands, some may remain at up to 2,000 metres (6,600 ft). NominateA. s. spinoletta winters mainly in western and southern Europe and in northwestern Africa; in western Europe some birds show fidelity to the same wintering site, returning each year.[5] Birds in Spain appear to move only lower down the mountains in which they breed.[10]A.s. coutellii winters at lower altitudes near its breeding areas and also in theArabian Peninsula and northeast Africa.A.s. blakistoni winters in Pakistan, northwest India and southern China.[5]
Water pipits leave their breeding sites from mid-September, although the eastern subspecies may start moving south before then. The spring migration starts in February and March, with arrival on the breeding grounds in April and May.[5] The water pipit has been recorded as a vagrant in Belarus,Gibraltar and Latvia, and on islands including theCanaries, Iceland, Malta andSvalbard.[1][10]
The water pipit is a much less approachable bird as compared to the European rock pipit. It is warier than its relative and if approached it flies some distance before landing again, whereas the rock pipit typically travels only a short distance, close to the ground, before it alights.[11]
The water pipit is mainlymonogamous, although both sexes may deviate from this occasionally. The male has a display flight in which he climbs to 10–30 metres (33–98 ft), flies in an arc and glides back down, singing throughout. The female constructs a cup nest from grass and leaves which is lined with finer plant material and animal hairs. The nest is hidden invegetation on the ground, sometimes in a hollow. The normal clutch is four to six eggs laid from the end of April to early July.[5] Eggs are greyish white with darker grey or brownish speckles mainly at the wider end,[9] and they measure 21 by 16 millimetres (0.83 in × 0.63 in) and weigh 2.7 grams (0.095 oz) of which 5% is shell.[14]
The eggs are incubated by the female for 14–15 days to hatching. Chicks are fed initially by the male, both parents sharing the duty after a few days when the female does not need to brood so often, and theyfledge in a further 14–15 days.[5] There may be two broods in a year.[14]
In a Swiss study of the nominate subspecies, 76% of eggs hatched, and 58% of chicks fledged. Birds of the raceA. s. blakistoni in theTian Shan hatched 90% of their eggs, and hatchlings survived to fledging in 47% of the nests. In the latter study, early nests were more likely to fail because less plant cover made them more likely to be found by predators.[10] Neither the average lifespan nor the maximum age of survival are known.[14][15]
The water pipit's feeding habitat is dampgrassland, rather than the rockycoasts favoured by the Eurasian rock pipit.[11] The water pipit feeds mainly on a wide range ofinvertebrates, includingcrickets and grasshoppers,beetles,snails,millipedes andspiders.Barkflies,true flies,caterpillars andhomopterans can form a large part of the diet of fledglings. Birds close tosnow fields take insects specialised for that habitat such as thespringtailsIsotoma saltans (theglacier flea) andI. nivalis, and thescorpion flyBoreus izyemalis.[10]
Birds normally forage alone or in pairs; in bad weather, foraging is more frequent and involves longer flights, and may be concentrated aroundmarmot burrow entrances. Prey items average 8.3 millimetres (0.33 in) in length and are mainly hunted on foot, although flying insects are occasionally caught in the air.[5] Some plant material is taken, and one study on the border of Czechoslovakia and Poland found that 75% of the diet by volume consisted ofalgae, specificallyUlothrix zonata, despite large numbers of insects being available.[10]
In areas with acidic soils, there is lesscalcium available, potentially leading to thinner egg shells. In such locations, pipits are more likely to select snails and similar prey with calcium-rich shells than is the case inlimestone terrain.[16]
The water pipit is hunted bybirds of prey including theEleonora's falcon,[17] and eggs and young may be taken by terrestrial predators includingstoats and snakes.[5] As with other members of its genus, the water pipit is a host of thecommon cuckoo, abrood parasite. Eggs of cuckoos that specialise in parasitising pipits are similar in appearance to those of their hosts.[18]
A new species offeather mite,Proctophyllodes schwerinensis, was discovered on the water pipit,[19] which is also a host to thefleasCeratophyllus borealis andDasypsyllus gallinulae.[20] Along with other Motacillidae species, the water pipit is a host of theprotozoan parasiteHaemoproteus anthi.[21]
Estimates of the European breeding population of the water pipit vary widely, but may be as high as two million pairs, which would suggest a global population of tens of millions of individuals spread over 3.7 millionsquare kilometres (1.4 millionsq mi).[1] The range is discontinuous due to the mountain habitat this species uses,[5] but the population is considered overall to be large and stable, and for this reason the water pipit is evaluated as aspecies of least concern by theIUCN.[1]
Breeding densities (in pairs per ten ha) have been recorded as 2.4 in theJura Mountains, 3.0–3.6 in theAlps and 4.5 in theTatra Mountains of Poland.[5][b]
