The great bustard, scientifically named Otis tarda, is the largest member of the bustard family of birds. Scientists regard the male great bustard as the world’s largest flying animal. A male great bustard is about 35-41 inches (90-105 cm) in length, has a wing span of about 83-94 inches (210-240 cm) and weighs 17-35 pounds (8-16 kg). Females are smaller, with an average length of about 30 inches (75 cm) and a weight of 7-12 pounds (3.0-5.3 kg). Great bustards have brown backs speckled with black bars and long grey heads and necks.
Geographically, the great bustard is found in scattered distributions from southern and central Europe through the Middle East, Russia and Central Asia to Mongolia. Great bustards have experienced declines in populations and have become regionally extinct in some European and north African nations such as Algeria and the United Kingdom. More than 50 percent of the estimated remaining 30,000-40,000 great bustards are found in either Spain or Portugal.
As a habitat, the great bustard is partial to extensive areas of open grass plains. These birds prefer river valleys and lowlands and will avoid rocky terrain as well as forests, wetlands and deserts. Agricultural areas are increasingly attractive places for habitation as long as the cultivated fields are not located too close to human settlements. Arable crops such as kale and oil seed rape will attract great bustards. Some populations of the great bustard are migratory and move in flocks to winter grounds.
The great bustard is an omnivorous eater. Its diet consists mainly of plant parts, seeds and insects. Occasionally, this bird will eat larger prey such as amphibians and reptiles. It also has been known to consume the chicks of other species.
Courtship rituals happen in the spring. Male great bustards might mate with as many as five females during breeding season. A male puts on an intricate display designed to attract females, and the display includes bending his head back to touch his uplifted tail. At the same time, he inflates his neck pouch and forms a fan of white feathers by pointing his wing feathers down and twisting them.
After the female has chosen her mate, she builds a nest in a shallow hole protected by low vegetation. Great bustards build their nests on dry plains and inclines. Females lay one, two or three eggs and receive no help from the male great bustard in incubating or caring for the chicks. The eggs hatch in about 21-28 days.