Britannica Sources used in this answer

Why do some birds in Australia make nomadic flights after unpredictable rains?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

A herd of wildebeest, including calves, moves across a dusty savanna in Africa with scattered trees visible in the background. — Migration A herd of common wildebeest (*Connochaetes taurinus*) migrating across a dusty savanna in Africa. The animal is a keystone species (i.e., a species with a disproportionately large effect on its biological community) in plains and acacia savanna ecosystems from southeastern Africa to central Kenya.

In the arid zones of Australia, certain birds—including ducks, parrakeets, and seedeaters—engage in nomadic flights as a direct response to irregular ecological conditions.1

Unlike regular migration, which is often tied to predictable seasonal changes, these nomadic movements are triggered by infrequent and unpredictable rainfall. When these rains occur, the birds arrive in a locality to breed, taking advantage of the temporary abundance of resources, before moving on to other areas. This behavior is an evolutionary adaptation to highly variable environments where food and water availability cannot be relied upon on a fixed annual schedule.1