Bustards: Otididae

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BUSTARDS: Otididae

GREAT BUSTARD (Otis tarda): SPECIES ACCOUNTS
BLUE BUSTARD (Eupodotis caerulescens): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Bustards vary in size from 15 to 47 inches (40 to 120 centimeters) in length. They are among the heaviest flying birds, weighing 1 to 42.2 pounds (0.45 to 19 kilograms). Male bustards are generally larger than females, although there is less difference between the sexes in smaller bustard species. Bustards have stout bodies with long legs and long necks. The bills tend to be short and straight. Bustards have large wings and small feet with no hind toe. Since Bustards do not perch on tree branches, preferring instead to remain on the ground, hind toes are not needed. The large wings are helpful when flying away from potential predators.

Bustards are generally colored to blend in with their environments. The back is brownish, with either white or dark bellies. Some bustard species have white or black patches on the wings, which are hidden when the wings are folded and only revealed during flight. In some species of bustards males and females are similarly patterned, while males are brighter in other species. In a number of bustards, males also have long feathers on the head, neck, or chest that are used to attract females.

GEOGRAPHIC RANGE

Bustards are found across much of the Old World, including Africa, Europe, and Asia, as well as in Australia.

HABITAT

Bustards are found primarily in grassland habitats with low vegetation where they are able to look out over long distances. Some bustards occupy taller grasslands or even slightly wooded areas. Bustards are also frequently found in cultivated fields.

DIET

Bustards are omnivores, consuming both plant and animal matter. They are opportunistic feeders who are often able to take advantage of any food. In most species, the diet consists mostly of plant matter, including leaves, shoots, flowers, roots and bulbs, fruit, and seeds. Individuals that occupy cultivated areas frequently eat crops as well. Bustards eat insects such as beetles and grasshoppers. Insects are a particularly important part of the diet during the breeding season, while chicks are being fed. Bustards sometimes eat larger animals as well, such as reptiles and rodents. In most cases, however, these animals are killed during fires or by traffic, rather than hunted by the bustards themselves.

Bustards are often seen foraging, or searching for food, near large herds of grazing mammals. This is probably because there is less danger from predators near other individuals. In addition, bustards may eat the insects which have been disturbed by the mammals.

BEHAVIOR AND REPRODUCTION

Bustards range from solitary, or, living alone, to highly social, forming groups of as many as thousands in the case of the little bustard. Bustards that occupy semi-desert habitats generally tend to be more solitary. Many species of bustards migrate, moving from a breeding habitat to a wintering habitat. Asian bustard species, in particular, frequently migrate to avoid harsh winter conditions.

SHOWY MALES

In many bustard species, males have special feathers that they use in courtship displays during the breeding season to attract females. These males put all their effort into mating with as many females as possible. They do not help with nest-building, with incubating the eggs, or with feeding or caring for the chicks once they hatch.

Bustards often breed during the rainy season in their habitat. Males perform elaborate courtship displays to attract females. These can involve booming calls, showing off long feathers that only the males possess, fanning out the tail, and performing leaps. Males generally do not participate in either nest building, incubating (warming) the eggs, or raising chicks. The female lays anywhere from one to six eggs at a time. These hatch after twenty to twenty-five days. Bustard young are precocial (pree-KOH-shul), meaning that they hatch at a fairly advanced stage of development. They are covered with down and are able to move, usually walking within a few hours of hatching.

BUSTARDS AND PEOPLE

Bustards play an important role in agriculture in some parts of their range by eating large numbers of insect pests. On the other hand, they are hunted in some parts of the world for food or sport. (In Asia, hunting has caused population declines in several species.) Some hunters use trained falcons to hunt bustards.

CONSERVATION STATUS

Of the twenty-six species of bustards in existence, four are considered Threatened with extinction and six are considered Near Threatened, in danger of becoming threatened. Most other species are also declining. Bustards are threatened primarily due to hunting (particularly in India and Indochina), habitat destruction, and pesticide use.

GREAT BUSTARD (Otis tarda): SPECIES ACCOUNTS

Physical characteristics: Male great bustards reach lengths of 41 inches (105 centimeters) and can weigh between 13 and 40 pounds (5.8 to 18 kilograms). Females are smaller, at 30 inches in length (75 centimeters) and 7 to 12 pounds (3.3 to 5.3 kilograms) in weight. Great bustards have black and gold barred backs and tails and white bellies. The head is pale blue-gray in color in females and nonbreeding males. Breeding males have white and rust colored feathers on the neck and long white barbs on the chin.

Geographic range: The great bustard has a scattered distribution and is found in portions of Morocco, Spain, Portugal, Germany, Hungary, Ukraine, Turkey, Iran, Russia, Syria, Uzbekistan, Tajikistan, Mongolia, and China.

Habitat: The great bustard occupies short-grass plains.

Diet: Great bustards eat plant material and insects. Sometimes they will eat larger animals such as reptiles, amphibians, and the chicks of other species.

Behavior and reproduction: Great bustards live in large groups, with the males found in separate groups from the females. Some great bustards are migratory, while others remain in the same place year-round. During the breeding season, males perform elaborate courtship displays, characteristic behaviors intended to attract female mates. Females lay two or three eggs at a time. These hatch after about twenty-five days. Chicks are able to fly after between thirty and thirty-five days.

Great bustards and people: In Europe, great bustards sometimes appeared on family insignias. The great bustard is also currently the symbol of a grassland conservation program.

Conservation status: The great bustard is considered vulnerable. Declines are primarily due to habitat destruction, pesticide use, and hunting. ∎

BLUE BUSTARD (Eupodotis caerulescens): SPECIES ACCOUNTS

Physical characteristics: The blue bustard has a brown back and blue-gray neck and belly. It is about 21.5 inches (55 centimeters) in length and 2.5 to 3.5 pounds (1.1 to 1.6 kilograms) in weight.

Geographic range: Blue bustards are found in eastern and central South Africa and in Lesotho.

Habitat: Blue bustards are found in grasslands as well as in cultivated fields. They are a high altitude species that is generally found above 4,900 feet (1,500 meters).

Diet: Blue bustards eat plant matter as well as insects and larger animals such as small reptiles.

Behavior and reproduction: Blue bustards are found in small groups of between two and six individuals. Blue bustard groups are territorial and defend their territories against other members of the same species. Blue bustards do not migrate but remain in the same place year-round. Breeding generally occurs in October and November. One to three eggs are laid by the female, and hatch after a period of twenty-four to twenty-eight days. Young remain with their parents for as long as two years.

Blue bustards and people: No significant interactions between blue bustards and people are known.

Conservation status: The blue bustard is currently considered Near Threatened. Population declines are generally due to habitat loss as grasslands are converted for use in agriculture. ∎