Water Rail Rallus aquaticus Scientific name definitions

25–28 cm; male 88–190 (128) g, female 74–138 (102) g; wingspan 38–45 cm. Female smaller, with shorter bill . In c. 60% of nominate birds , variable number of greater and median upperwing-coverts have white bars, black-bordered or on black feathers; white markings may also occur on alula, primary-coverts and even remiges, while some have white speckles on mantle, back or rump; undertail-coverts usually appear white but may have variable amounts of buff, and sometimes show black barring; pattern has been used for individual recognition; iris red; bill red, culmen and tip reddish black; legs flesh-brown, often tinged reddish or green. Differs from <em>R. indicus</em> mainly in having no (or only vestigial) dark eyestripe, less extensive white on throat, darker grey underparts lacking brown tinge, and few or no (indistinct) black bars on undertail-coverts. Differs from all American congeners, except R. wetmorei, in lacking contrasting rufous or chestnut on upperwing-coverts. R. caerulescens of sub-Saharan Africa is larger, with unstreaked, deep vinous-brown upperparts and brighter red legs and feet. Immature very like adult but duller, with whiter chin, small pale supraloral streak, olive-brown patch on ear-coverts, olive-brown tinge on breast, and duller legs and feet. Juvenile may have duller upperparts; grey of head and underparts replaced by buff or white with brown to black bars and feather tips; flanks buff with dark brown to black bars; undertail-coverts often appear entirely buff; bare parts dull. Races separated by plumage: hibernans  and <em>korejewi</em> paler than nominate on underparts, and korejewi also on upperparts.

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Closely related to R. caerulescens and R. madagascariensis. Until recently considered conspecific with R. indicus, which differs in its broad brown vs no or vestigial eyestripe (2); whiter preocular superciliary with markedly darker brown crown (ns[2]); more extensive white on throat (ns[2]); underparts paler grey with brown tinge, especially on breast (2); bold black bars on undertail-coverts (2); markedly different voice, song being a “cranking, rhythmic series of identical strident, metallic yet musical, upslurred SKRINK, SKRINK” vs “a single braying, squealing, pig-like SKREEEr that descends near end” (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia. The Ripley Guide. Volumes 1 and 2. Smithsonian Institution, Washington, DC, USA and Lynx Edicions, Barcelona, Spain. Close ) (3). Proposed races arjanicus (from S Iran) and deserticola and tsaidamensis (both from N Qinghai, in WC China) are all regarded as synonyms of korejewi. Three subspecies recognized.

Editor's Note: Additional distribution information for this taxon can be found in the 'Subspecies' article above. In the future we will develop a range-wide distribution article.

Occupies almost any type of dense riparian and aquatic vegetation at still or slow-moving water; usually requires muddy ground for foraging; suitable habitat may form small pockets or narrow strips in other habitat types. Breeding habitat includes reedbeds and other emergent vegetation of swamps, marshes and fens, and at fringes of open water ; also occurs on floating islands, rice paddies and lotus ponds. Occurs at both fresh and saline lakes and marshes. On migration and in winter exploits wider range of habitats, such as farm sewage outfalls, island bracken, flooded thickets of blackberry (Rubus), gravel pits and other very small wetland patches; even, when displaced by frost, drainpipes, rubbish dumps, open ditches and gardens. In Iceland in winter largely dependent on marshy areas with warm water from volcanic springs. Vulnerable to extreme conditions, e.g. ice or severe floods. Mainly lowland, but resident up to 2000 m.

Nominate race both sedentary and migratory, birds from N of range moving S & SW to winter in Mediterranean basin, N Africa (extending far into Sahara, in Algeria and Libya) and E to S Caspian area. In Europe and Russia autumn migration begins Aug, peaks Sept–Oct, ends Dec; spring migration begins Feb, peaks Mar to mid-Apr and ends by May. Passes through Morocco Sept, Algeria Sept–Oct, Egypt Sept–Nov; occurs coastal Libya Oct–Apr and at Saharan sites Dec–Apr. Passage recorded Azerbaijan Sept–Nov and Mar–May. Scarce passage migrant in Oman, occasionally overwintering; occurs Aug–May. Has bred in Cyprus and wanders to Spitsbergen, Madeira, Canary Is and Azores. Race hibernans probably migrates to Faeroes in winter, occurs on passage at Scottish islands and in winter in Ireland, and wanders to Greenland and Jan–Mayen. Race <em>korejewi</em> partly migratory and wanders to Sind and NW India, and to E Arabia. Migrates at night, on broad fronts, and even crosses mountain systems such as Alps.

Worms, leeches, molluscs, shrimps, crayfish, spiders, many terrestrial and aquatic insects and their larvae (including Dermaptera, Odonata, Trichoptera, Hemiptera, Coleoptera, Diptera, Lepidoptera, Orthoptera), and small vertebrates (killed or as carrion) including amphibians, fish, birds and mammals. Plant foods include shoots, roots, seeds , berries and fruits; eats more plant material in autumn and winter. Forages on dry ground or mud near water; also wades in shallow water , taking items on and below surface, and from emergent vegetation; sometimes feeds while swimming, rarely by diving. Leaps up to take insects from vegetation; climbs in vegetation to take berries; flies into apple trees to remove fruit.

Announcement call (known as “sharming”) comprises grunting notes rising in middle of call to high-pitched, trilling whistles, likened to piglets squealing; pair-members often call antiphonally in duet, male giving lower notes. Courtship-song rendered “tyick-tyick-tyick” , often ending with trill, “tyüirr”; also gives series of “tick” notes followed by wheezy scream, and various groans, grunts, purrs and whistles. Calls  usually given from cover; vocal by day throughout year; may call all night early in breeding season.

W & C Europe, late Mar to Aug; Morocco and Algeria, May–Jun; Tunisia, Jun; Egypt, Apr–Jun; former USSR, May; Kashmir, Jun–Aug; two broods normal. Monogamous; highly territorial when breeding. Nest a substantial cup of dead leaves and plant stems; usually in thick vegetation of reeds or rushes on ground near or in water, rarely on tree stump or in open; surrounding vegetation often pulled down into loose canopy. External diameter 13–16 cm; height c. 7 cm; may be built up if water level rises. Both sexes build. Usually 6–11 eggs (5–16), laid at daily intervals; replacements laid after egg loss; incubation 19–22 days, by both sexes; chicks  precocial; black downy chick has visible patch of red skin on hindcrown, white bill with black base and tip, grey to brown-black iris and grey-brown to blackish legs and feet; fed and cared for by both parents, apparently only until 20–30 days old; initially brooded and fed mainly in nest; begin to feed themselves at c. 5 days; fully independent and capable of flight at 7–8 weeks; post-juvenile moult starts soon after fledging (c. 10 weeks) and is usually finished by Jul–Oct. Age of first breeding 1 year.

Not globally threatened (Least Concern). No evidence of significant changes in status of nominate race, which is regarded as locally common over much of range, including N Africa and Azerbaijan, although wetland habitat loss must have affected its numbers. Has benefited locally in UK from increased habitat provided by gravel pits and disused canals. Race hibernans   was most numerous in S of Iceland; current status not clear, but reported as very scarce in some areas, and may possibly be extinct. Current status of race korejewi unclear in many areas, but formerly regarded as at least locally common.