Finland Times

In addition, there are large differences among the populations of different species regarding displacement.

Over the last 30 years, bird populations have moved to north-northeast an average of 37 kilometres.

Over the same period, climate conditions suitable for the birds have moved north an average of 186 kilometres.

For forest animals, suitable habitats are found throughout the country. By contrast, mountain ptarmigans are in a different, more difficult situation.

These game birds can only move higher and higher toward the apex of the mountains, or to the taller mountains of Norway and Sweden.

The study looked at the migrations of 128 species of birds, their breeding densities and distribution areas by temperature conditions in Finland.

It was published in a science series by the Global Change Biology.