This post presents photos from the Special Feature” Stuck in motion? Reconnecting questions and tools in movement ecology ” from the current issue (85:1) of Journal of Animal Ecology

Wild mountain reindeer. Photo: wild reindeer.

Taken from GPS collars equipped with wide-angle cameras, these amazing shots represent an unprecedented window into the lives of reindeer, one of the most ancient deer species in the world. Few people are aware that within the heart of Europe there still exist mass migrations as spectacular but more secretive than those in the Serengeti. Yet, reindeer migrations represent one of the most endangered phenomena in the Northern hemisphere. Wild reindeer are extremely wary of humans, who have been harvesting them since pre-historic times using large-scale pitfall systems. Their anti-predator strategy consists of aggregating in large herds roaming across vast mountain plateau in southern Norway, and avoiding human activities. Following the industrial revolution, the development of anthropogenic infrastructures has therefore led to the fragmentation of the last remaining wild mountain reindeer population into 23 virtually isolated sub-populations, and has hampered/blocked migration routes used since pre-historic times. Due to the increase in tourism, hydropower and other human activities in mountain areas, fragmentation is rapidly ongoing.

Researchers at the Norwegian institute for Nature Research are remotely collecting data on the movements of ca 300 wild reindeer across the major populations in an attempt to better understand reindeer spatial requirements, the reasons underlying migration, quantify the impact of infrastructure, and aid the process of identifying mitigation measures and re-establishing connectivity among key sub-populations. The pictures taken from the cameras incorporated in some of these collars provide unprecedented and precious information on reproduction, feeding habits and other aspects of reindeer behavior, which would be challenging to obtain in other ways, for such secretive animals living in such a harsh environment.

Slideshow

Wild reindeer migrations represent one of the most spectacular and endangered phenomena in the Northern hemisphere. In this picture several thousand reindeer move together across Hardangervidda – the largest mountain plateau in Europe and Norway’s largest National Park. Hardangervidda hosts the largest remaining population of wild mountain reindeer, counting ca. 11000 individuals. Photo: «Bella», a wild reindeer equipped with a camera attached to its GPS collar.

Wild mountain reindeer live in vast open spaces above the treeline in Norway, and their main antipredator strategies are grouping into large herds, and fleeing. Reindeer are very sensitive to anthropogenic disturbance, and the sight of a snow mobiles, a snowkyter, or just a few individuals on skis can be enough to trigger flight. Therefore, human disturbance has to be strictly regulated in reindeer areas. Photo: wild reindeer.

Reindeer need to roam vast areas to find enough food in this harsh environment covered by a thick layer of snow for several months a year. During winter lichens are the only accessible food source, to be found mainly in wind-blown ridges. Although lichens are very low in protein, they are crucial to survival for reindeer herds. Photo: wild reindeer.

Climate change is increasing the rate of icing events (rain-on-snow), which prevent reindeer from accessing lichens, their main/only winter food source. When icing occurs, reindeer can only survive by moving to ice-free areas. It is therefore crucial to allow reindeer to move, and mitigate habitat fragmentation. Photo: wild reindeer.

Reindeer are well equipped for enduring temperatures of -30⁰C or more. Their fur coat is very thick and it is composed of hollow, tubular hair providing exceptional insulation. Photo: wild reindeer.

During the frequent snow storms reindeer gather in tight groups, lie down, and let the snow cover them to provide additional insulation. Photo: wild reindeer.

In the coldest winter days, a tight proximity within the herd increases thermal insulation. Photo: wild reindeer.

In Hardangervidda National Park, herd size can count up to several thousand reindeer. Here the herd is migrating towards the calving ground. Photo: wild reindeer.

Calves are born in mid-May, at the time when the snow starts melting and the vegetation starts greening. The does are now in need of high-energy food, after an energetically stressful pregnancy carried out throughout the harsh winter months. Photo: wild reindeer.

Hot summer days can be hell for reindeer. Parasitic insects such as warble flies and nose bot flies harass the herds, which gather in tight groups and search for relief in high-altitude snow-patches where the temperature is too low for the insects. Photo: wild reindeer.

Reindeer are one of the most ancient deer species, and provided an important food source for primitive humans moving northwards following the retreat of the ice during the last glaciation. Here a herd of reindeer roam across one of the largest glaciers in Norway – the Hardangerjøkulen. Photo: Olav Strand, NINA.

During spring and summer, the nutrients contained in green vegetation are crucial to compensate for the high energy requirements during lactation, and for accumulating enough fat reserves to survive the coming winter. Photo: wild reindeer.

Snowbed vegetation is a favourite summer forage for reindeer. It can be found in hollows and depressions where winter snow takes a longer time to melt, meaning that fresh and nutrient-rich shoots can be found in full summer. Photo: wild reindeer.

The herd from Forollhogna National Park, central Norway, is well-known for its large bucks with their magnificent antlers. Photo: Olav Strand, NINA.

Winter forage is essentially represented by lichens, which are the only accessible food item in wind-blown ridges. Photo: Olav Strand, NINA.

Manuela Panzacchi
The Norwegian Institute for Nature Research