The corncrake (Crex crex) is a medium-sized, migratory bird belonging to the rail family, which includes coots and moorhens. Unlike many relatives, the corncrake is a dry-land species, spending its life hidden within dense meadow vegetation across Europe and Asia. It is famous not for its visual presence, but for a loud, grating nocturnal call that announces its arrival in summer breeding grounds. Its secretive nature means it is heard far more often than seen.
Appearance and Physical Characteristics
The corncrake measures approximately 27 to 30 centimeters in length, similar in size to a partridge. Its plumage provides excellent camouflage, featuring brownish-black upperparts heavily streaked with buff and grey. This cryptic coloration allows the bird to blend into the tall, dry grasses of its preferred habitat.
A male corncrake’s face, neck, and breast display a blue-grey coloration, differentiating it from the female, which has warmer, less-defined tones. The wings are a rich chestnut-brown, noticeable when the bird is forced into flight. It possesses a strong, flesh-colored bill and pale grey legs, adapted for walking and running through dense cover.
Elusive Behavior and Distinctive Call
The corncrake’s scientific name, Crex crex, is an onomatopoeic derivation referencing its unique vocalization. The male’s call is a loud, repetitive, mechanical sound, often described as a harsh rasping noise, like two wooden sticks being rubbed together. This sound is used to establish territory and attract a mate during the breeding season.
The call is most frequently heard during the late evening and throughout the night, sometimes continuing for hours, and it can carry for up to one kilometer. This persistent vocal display is the primary method of detecting the species, as the bird is difficult to flush from cover. When disturbed, the corncrake chooses to walk or run quickly through the dense vegetation rather than take to the air, relying on agility and camouflage.
Habitat, Range, and Diet
The corncrake is a long-distance migrant, breeding across Europe and western Asia, extending eastward to western China. It seeks out tall, dense meadow vegetation, hayfields, and traditionally managed grasslands for nesting. These habitats provide the necessary cover for its ground-nesting habits and a source of food.
Following the breeding season, the population undertakes migration to its non-breeding grounds in Africa, primarily south of the Sahara Desert. This journey of thousands of kilometers is impressive for a bird with relatively short, rounded wings. The corncrake is an omnivorous species, with its diet shifting depending on the season and location.
Its nutrition is heavily weighted toward animal matter, consisting of approximately four-fifths animal food and one-fifth plant material. The bird forages for invertebrates such as insects, spiders, earthworms, slugs, and snails. Plant consumption increases in the autumn, when it feeds on seeds to build up fat reserves necessary for its long migratory flight.
Conservation Challenges
The corncrake has experienced significant population declines across its historical European range, largely due to changes in modern agricultural practices. The primary threat stems from the mechanization and earlier timing of hay and silage harvesting. Traditionally, meadows were cut later in the summer, allowing the corncrake chicks to hatch and fledge.
Modern farming often involves multiple, earlier cuts of grass, coinciding with the bird’s nesting period in June. This early mechanical mowing destroys ground nests and kills eggs and young chicks before they can escape. Although the species is globally listed as Least Concern, severe decline in many Western European countries means it is classified as a high conservation priority there.
Conservation efforts focus on working with farmers to implement corncrake-friendly land management techniques. These measures include delaying the mowing of hayfields until after the breeding season, often until August, to allow young birds time to mature. Establishing early and late cover refuges, such as patches of tall herbs or nettles, provides safe areas for the birds upon arrival and before departure.