The common crane forages by day, probing with its beak or picking up food from both land and water. The diet includes a wide range of plant and animal matter, including roots, shoots, tubers, leaves, grain and nuts, as well as various invertebrate and small vertebrate prey, and occasionally birds’ eggs (2) (4) (6) (9). Outside the breeding season, this crane gathers and migrates in large flocks, but during the breeding season, from April to June, each breeding pair occupies a large nesting territory (4) (6) (9). Breeding pairs are monogamous (4) (6), reinforcing the pair bond with ‘unison calling’, a complex series of coordinated calls given with the head thrown back and the beak pointed skywards (7). All ages and sexes also engage in ‘dancing’, a variety of bows, bobs, leaps, running, and tossing of vegetation, most commonly used in courtship, but also associated with aggression (6) (7).
The nest, which may be used from year to year, is a mound of wetland vegetation, generally placed on the ground in or near water (2) (6) (7) (9). Both the male and female help build the nest and incubate the two eggs, which hatch after 28 to 31 days (2) (4) (6) (7). During this time, the adults may use mud or decaying vegetation to ‘paint’ the upper body and wings reddish brown, an intriguing behaviour that may provide camouflage (6). The chicks have brown plumage, and fledge at around 65 to 70 days, but take between 4 and 6 years to reach maturity (2) (6). Every two years, before migration, the adult common crane undergoes a complete moult, remaining flightless for six weeks, until the new feathers grow (6) (9).