The western water rail (Rallus aquaticus) belonging to the family Rallidae, is a water bird, inhabiting wetlands, mangroves and marshes. These rail species are distributed in Indian subcontinent, Europe, North Africa and West and Central Asia. Earlier Rallus aquaticus and R. indicus were clubbed together as R. aquaticus.
Taxonomy of Western water rail
- Scientific Name: Rallus aquaticus
- Common Name: Western water rail
- French: Râle d’eau; German: Wasserralle; Spanish: Rascón europeo;
- Other names: Water Rail;
- Family: Rallidae › Gruiformes › Aves › Chordata › Animalia
- Species author: Linnaeus, 1758
DescriptionThe western water rail are small birds measuring 25 to 30 cm in length. The male birds weigh 90 to 190 grams and the females between 70 to 140 grams. The wingspan is 40 to 45 cm. But for size, both male and female rails look alike. The body is laterally flattened and well adapted for movement among reeds. The upper parts are brown and the belly is blue-gray. There is black-brown barring on the flanks. The beak is long and reddish. The legs and toes are long. The tail is short and the underside is whitish. Their call is a series of grunts followed by a high-pitched piglet-like squeal and ending in grunting sounds.
|Indian birds - Western water rail - Rallus aquaticus|
|Birds of India - Western water rail - Rallus aquaticus|
|Indian birds - Water rail - Rallus aquaticus|
|4.Birds of India - Water rail - Rallus aquaticus - portrait|
HabitatThese rail species inhabits well-vegetated wetlands, marshes, reed-marsh, dense scrub jungles near water sources, clay pits, gravel pits, peat excavations, rice paddy-fields, canals and dense mangroves. They prefer shallow or slow flowing water with emergent or submerged aquatic vegetation.
Feeding habitsThe western water rails are omnivorous, feeding both on small animals and plant matter. They feed on seeds, grass, shoots of marsh plants, berries and buds. These rail species also feed on terrestrial and aquatic insects and their larvae. They feed on mollusks, shrimp and crabs.
BreedingThe western water rail breeds during March to August in west and central Europe. In north Africa, West Asia and Indian subcontinent the breeding season is mainly between May and June. These rail species are monogamous and highly territorial during the breeding season. The nest is built on raised ground and may contain 6 to 12 eggs. Though both the rail parents incubate the eggs, the female takes a major share in incubation. The food is brought to the nest for feeding the hatchlings.
DistributionThe western water rail subspecies R. a. korejewi is distributed in Aral Sea lying between Kazakhstan and Uzbekistan, Lake Balkhash in southeastern Kazakhstan, Iran, Kashmir in the Indian subcontinent and West-central China. The rail subspecies R. a. aquaticus is distributed in Europe, North Africa, Turkey, western Asia and western Kazakhstan. The rail subspecies R. a. hibernans was distributed in Iceland and became extinct around 1965, as a result of loss of habitat through the draining of wetlands and predation.
Movement and migration PatternsThe western water rail species breed across temperate Europe and Asia and migrate southwards for wintering in North Africa and west Asia. The western and southern rail populations are mainly sedentary. The southward migration occurs during August to December and the return to the breeding grounds occurs between late-February to mid-April.
Conservation status and concernsThe western water rail global population size is estimated to be between 100,000 to 1,000,000 adult birds. There appears to be a steady decrease in the rail population. Habitat loss, increased human activities in the wetlands are the main threats to the survival of these rail species. The subspecies R. a. hibernans had become extinct mainly due to predation by the introduced American mink, classified as an invasive species in Europe.
The IUCN (International Union for Conservation of Nature) has categorized and evaluated these western water rail species and has listed them as of "Least Concern".
1.Image source: https://en.wikipedia.org/wiki/File:Ralaqu.jpg
Image author: Pierre Dalous | License: CC BY-SA 3.0
2.Image source: https://commons.wikimedia.org/wiki/File:Wasserralle_Spiegelbild.JPG
Image author: Sgbeer | License: CC BY-SA 4.0
3.Image source: https://commons.wikimedia.org/wiki/File:Rallus_aquaticus_1_(Marek_Szczepanek).jpg
Image author: Marek Szczepanek | License: CC BY-SA 3.0
4.Image source: https://commons.wikimedia.org/wiki/File:Rallus_aquaticus_portrait.jpg
Image author: Yerpo | License: CC BY-SA 4.0
Current topic in Birds of India: Western water rail - Rallus aquaticus.