Reindeer near the village of Vuollerim in Lapland.
Because they cannot find any food under the hard layers of ice, they move about.
Photo: JONATHAN NACKSTRAND / AFP
Many reindeer native to Lapland are increasingly moving long distances south in search of food because of the effects of climate change.
"Reindeer cannot penetrate ice because it is too hard and so they move away in search of areas where there is only snow," said researcher Jouko Kumpala from the Finnish Institute for Natural Resources to the BBC.
Snow could easily penetrate the animals and eat the plants underneath.
As a result of global warming, the report says that snow melts earlier or rain falls on the snowpack - which leads to hard ice sheets when temperatures drop.
Some reindeer travel distances of up to 100 kilometers to find food, as reported by breeders from the BBC.
Scientists assume that the Arctic will warm at least twice as fast as the rest of the world as a result of climate change.
Many Sami, as the indigenous people of Lapland are called, live from reindeer herding.
Lapland includes the northern part of Finland, but also regions in Sweden and Norway.
8000 animals on the move
According to the report, some of the breeders are busy around the clock tracking down the runaway reindeer.
“We drive for hours and hours to find our reindeer and drive them back home, but that's pretty difficult in these wintry conditions.
That's why we also use helicopters, which is quite unusual - and also expensive, "said the Swedish owner Tomas Seva.
Around 8,000 animals from his herd and a nearby village have left their usual fields in the past few days.
According to the Swedish Reindeer Keepers Association, reindeer excursions have become much more frequent.
In the past, you only experienced such winters every 30 years, said Anna-Karin Svensson from the association.
"It seems that these are becoming more common now because of climate change."
kik / dpa