The great bustard is a flying heavyweight whose males dwarf the females
A male great bustard collected in Manchuria weighed about 21 kg, a verified record for any flying bird. Its mate might weigh a fraction of that: in Spain, males averaged nearly two and a half times the mass of females, the largest size gap between the sexes of any living bird.
The species name tarda is Latin for slow and deliberate, describing its stately walk, and the phrase for slow bird gave English the word bustard by way of Old French. Males stand up to about a metre tall with wings spanning more than two metres, brown and barred above, white below, with a grey head and chestnut breast. In spring they sprout long white whiskers of bristle-like feathers. Disturbed birds prefer to run rather than fly, and females have outpaced foxes, yet in migration they are strong fliers, some travelling over 2,000 km from Mongolia to China.
Courtship is theatrical. Males settle rank in winter by ramming and pecking one another, then gather on a lek in spring. A displaying male inflates his throat to football size, buries his head, flips his tail flat on his back and fans out white feathers until he resembles a heap of foam, sometimes holding the pose for minutes while waiting for hens. One male may mate with as many as five females. Each hen lays one to three glossy eggs in a shallow scrape, incubates them alone for three to four weeks, and keeps the chicks close for up to a year.
These birds need open, quiet grassland or lightly farmed land and avoid regular human activity during breeding. Declines have been steep. Britain lost its last bird to a gun in 1832, Iran's population had shrunk to 19 by early 2025, and the species was classed as endangered in 2023. Spain now holds more than half the world's population, around 30,000 birds.
Recovery efforts continue. Since 1998 a reintroduction project has been returning great bustards to Salisbury Plain in England, where an army training area keeps the public away and gives these shy ground-nesters the seclusion they need.
Source: Great bustard
