Geese have changed their migration paths on leaving Britain due to climate change, reveals a long-term study.
Researchers discovered that barnacle geese have shifted their migratory route within the last 25 years.
The team concluded that individual geese have decided to change to the new route, and that other geese now learn the new habit from each other.
The study, published in the journal Global Change Biology, is among the first to provide hard evidence that wild animals are inventing new traditions to cope with climate change.
The migratory birds, who traditionally stopped to refuel just South of the Arctic circle in Norway on their journey from the UK to their breeding grounds on Svalbard, now mainly stop off instead in northern Norway far above the Arctic Circle.
The conclusions are based on analysis of 45 years of observations by the Norwegian Institute for Nature Research, the University of St Andrews in Scotland, the University of Groningen in the Netherlands, BirdLife Norway and the British Waterfowl and Wetlands Trust.
Dr Thomas Oudman, of the School of Biology at the University of St Andrews, said: “It makes sense that the birds went even further North, because where snow used to be very common there at the time of their arrival in Norway, these days it is often freshly green there: the most nutritious stage.
“What surprised us is that it is mainly the young geese who have shifted. The youngsters are responding to a trend they could not have experienced during their short life.”
He said adult geese are also increasingly shifting north, although they often return to the traditional area in their old age.
Dr Oudman added: “These patterns point at a complex social system, which enables the geese to rapidly colonise newly available areas.”
Contrary to most other migratory birds, the research team said barnacle geese flourish even while their natural habitat is rapidly changing.
They said barnacle geese are able to adapt to climate change due to the availability of alternative places with sufficient food at the right time, and without the threat of disturbance from humans or other dangerous animals.
The availability of alternative habitats may also help other animals to adapt to climate change, according to the researchers.
But animal species that are not so explorative and which are less sociable may take much longer to discover such places.