Wild reindeer are especially sensitive to climate change. Foto: © Olav Strand og Roy Andersen / NINA

The right climate for wild reindeer?

Living as they do in ever-decreasing areas of barren mountain moorland, wild reindeer are especially sensitive to climate change. Is there anything we can do to improve conditions for wild reindeer?

Chronicle by Ellen Hambro
Director General of the Norwegian Environment Agency

On august 26, 323 wild reindeer were killed by lightning strikes during a violent thunderstorm on the southern Hardangervidda moors I Norway. The news went around the world, in media such as the Washington Post, the New York Times and Al Jazeera. This incident was probably the rare coincidence of a number of unfortunate circumstances, although we do now expect more extreme weather as the climate changes.

Even so, this is a reminder of how an unforeseen natural phenomenon can affect the wild reindeer population, despite our best efforts to manage them. It took many years to build up the population in the western area of Snøhetta again, after 280 animals were killed by an avalanche some years ago.

Reindeer forest

Norway has a special international responsibility for protecting the remains of the original Western European wild reindeer population, which today live in 23 different areas in the mountains of southern Norway. One immediate thought might be that the effect of climate change would be to move the tree line higher and leave less bare mountain for the reindeer. This will take time however, and there are many examples of wild reindeer herds living mainly in forested areas. A great deal of tame reindeer herding takes place in forested areas.

The effects of climate change will probably be different in different wild reindeer areas, but the most important thing is whether the reindeer can access the plants they need for grazing at different times of year.

People create barriers

At the time when reindeer were able to migrate freely between the mountain areas, it was natural for them to move westwards for calving and summer pasture. On the steep, snow-rich slopes nearer to the coast, the reindeer can follow the melting snow upwards during the summer and gain constant access to new, protein-rich plants. It is also easy to find snow patches here, where they can escape from troublesome insects on warm days.

In winter, the reindeer used to trek back to the eastern mountain areas with their more continental climate, with less and looser snow and better access to the lichens that they graze on. Today, these great seasonal migrations are prevented by various man-made barriers.

The classic example is Dovrefjell. The Snøhetta population there is shut off in the former summer grazing area, while the Rondane and Knutshø populations on the other side of the European route E6 and the railway are restricted to the former winter grazing areas. The anticipated climate change will probably increase the problems that this causes for the reindeer, and we may be seeing the effects already.

The snow patches are disappearing

In recent years there have been a number of finds of very well preserved arrows and other hunting-related objects around mountain snow patches that are melting away. These are unique cultural treasures that also demonstrate how important these summer snow patches were for the reindeer hunters in former times.

I am concerned that snow patches that have existed for perhaps thousands of summers are now disappearing. Fewer snow patches mean less opportunity to cool off and escape the insect pests. The consequence is probably that the animals are in poorer condition, because of both the increased parasite problem and increased use of energy. We expect there to be more parasites, such as subcutaneous warble flies and nose bot flies, as a direct consequence of climate change.

Our national monitoring programme has established that the weight of wild reindeer has been reduced and reproduction has been poorer in several wild reindeer areas over the last decades. The researchers have not yet found any clear, unambiguous reason, but possible causes they indicate include a warmer climate and the fact that reindeer are being forced together into smaller areas because of human interference.

The critical winter

In terms of food, winter is the most critical period for wild reindeer. The mountain areas in which they live may appear endless, but when the snow becomes more compacted it is really only on wind-blown ridges that the reindeer can find the lichens they need both to maintain their own body weight and to carry a calf. That means a life of constant wandering.

Climate change also brings milder winters to the mountains, with more snow in the western mountain areas and more mild weather and rain generally. This can create a thick layer of ice in the snow that the reindeer cannot dig through and an armour of ice on the lichen ridges. This forces the reindeer to move eastwards, where there is a more continental climate with less and looser snow, such as the eastern rim of Hardangervidda. However, here they come up against man-made barriers in the form of roads, chalet developments and ski areas. This limits access to the grazing areas that the reindeer so sorely need.

The wild reindeer need “emergency exits”

It is therefore vitally important that we manage to preserve the last opportunities to migrate out into such “reserve” areas and to reduce the obstacles. This can be done by closing roads, or not snowploughing them, avoiding snow scooter traffic and diverting or closing ski trails when conditions for the reindeer are difficult.

There is no clear-cut answer as to how climate change will affect wild reindeer in the short and long term, but there are many indications that the sum of the effects will be negative. This means that we must continue to work hard to cut greenhouse gas emissions and to reduce some of the problems for the reindeer that we can do something about.

We in environmental management can help by improving the knowledge base through a continued focus on research and monitoring and by making the necessary changes in the management of the reindeer population. Local and county authorities must also do their part of the job by using the zoning of land use to ensure access to important grazing areas. 

Contact

senior advisor Vemund Jaren
Wildlife Section
Telephone +47 901 02 369

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