Bar-headed goose (Anser indicus)

Identification and characteristics

Adults display a light grey body, white facial markings and strong, broad wings suited to long flights. The distinctive paired dark bands across the nape are often described as "bars" and are a key field mark for identification: dark head bars. Like other waterfowl, they have webbed feet and a bill adapted for grazing.

Range, habitat and migration

Breeding populations are concentrated in high-elevation lakes and wetlands of Central Asia. In winter they disperse to lower-altitude wetlands, floodplains and agricultural fields. Typical habitats include wetlands and marshy basins: wetland areas, often in Central Asia. The species is famous for seasonal movements that can cross mountain ranges at very high elevations.

Physiological adaptations

Bar-headed geese possess several adaptations that support flight in low-oxygen, cold conditions. These include efficient breathing mechanics, a circulatory system that supports oxygen delivery, and muscle properties that maintain performance during strenuous, high-altitude flight. These traits have made the species a subject of physiological and ecological research.

Diet, breeding and conservation

The diet is primarily vegetarian: they graze on grasses and forage in croplands. Common food items include grass, wheat, barley and rice. Breeding occurs near water with nests placed on islands or shorelines; pairs defend territories during nesting. Populations face pressures from habitat change, disturbance and hunting in some regions, but their wide range and adaptability mean they are not uniformly threatened.

Notable facts

• Recognized for regular high-altitude flights over mountain ranges.
• Distinctive twin dark bands on the nape aid quick field identification.
• Often studied to understand adaptations to hypoxia and endurance flight.