Effects of mining on reindeer habitat use and reindeer herding in Sodankylä, northern Finland
This study reveals that the Kevitsa mine in northern Finland significantly alters reindeer habitat use by creating seasonal avoidance zones up to 1.9 km wide during summer, yet the broader herding district has maintained stable herd numbers through modern management practices like supplementary feeding that decouple herd size from natural pasture limitations.
Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer
In the far north of Finland, where the landscape is a vast tapestry of pine forests, peat bogs, and tundra, reindeer herding is not merely an industry but a centuries-old way of life. These animals are semi-domesticated, meaning they are owned by people but roam freely across thousands of square kilometers of public and private land for most of the year. Their survival and the success of the herders depend entirely on the availability of high-quality pasture. However, this open range is increasingly crowded by other human activities. When a new road, a wind farm, or a mine appears, it does more than just occupy a patch of land; it creates a zone of disturbance that can push the animals away, effectively shrinking the usable grazing area without a single fence being built. Understanding how these massive industrial changes alter the behavior of a free-roaming herd is critical, not just for the animals, but for the communities that rely on them.
This question lies at the heart of a study conducted in the Oraniemi herding district, a region in northern Finland that has been home to reindeer for generations. In 2012, the Kevitsa nickel and copper mine opened within this district, fencing off a large area of land to protect the operation and keep the reindeer out. The researchers wanted to know exactly how this industrial giant changed the daily lives of the reindeer. Did the animals simply avoid the mine fence, or did they steer clear of a much wider area? And did this behavior change depending on the time of year? To find out, the team tracked 113 female reindeer equipped with GPS collars between 2015 and 2020. By comparing where the animals actually walked against the types of terrain available to them—such as forests, bogs, and water—they could map out the invisible boundaries the mine created in the minds of the herd.
The results revealed a story of two very different seasons. During the summer, which includes the months of May through July when calves are born and raised, the reindeer showed a strong and clear desire to stay away from the mine. The data showed that the animals avoided the mining area up to a distance of nearly 1.9 kilometers from the fence. This is a significant buffer zone, effectively removing a large swath of potential grazing land from the herd's daily routine. The researchers noted that this behavior makes sense for female reindeer with young calves; they naturally seek out quiet, secluded areas to protect their offspring from disturbance. The mine, with its constant activity and human presence, represented the opposite of that safety.
In contrast, the autumn months told a different story. From September through December, as the reindeer prepared for winter by fattening up on available forage, their avoidance of the mine became much weaker. The zone where they reduced their grazing shrank significantly from the fence. In fact, the animals were willing to graze much closer to the mine during this time. The researchers suggest that the pull of high-quality autumn food, such as grasses and mushrooms found in the forests near the mine, outweighed the discomfort of the industrial noise and activity. While the calves were still with their mothers, they were older and less vulnerable, allowing the herd to prioritize feeding over seeking total seclusion.
The physical impact of the mine is substantial. The fenced-off area itself covers about 15 square kilometers, land that is completely unavailable to the reindeer. When you add the seasonal zones where the animals choose not to graze, the total area of lost or reduced pasture is even larger. This has forced local herders to abandon a traditional gathering corral that once stood just north of the mine, as it became impossible to drive the herd there for the annual roundups. The migration routes have shifted, and the herders have had to adapt their management strategies to navigate a landscape that has been permanently altered by the presence of the mine.
Despite these local disruptions, the overall health of the reindeer herd in the Oraniemi district has remained stable. The study found that the total number of reindeer and the number of animals slaughtered have not dropped since the mine opened. This resilience is largely due to modern herding practices. Herders now rely heavily on supplementary winter feeding, bringing in hay to support the animals when natural pastures are covered in snow or when the available grazing is too small to sustain the herd on its own. This shift has decoupled the size of the herd from the strict limitations of natural winter grazing, allowing the community to absorb the shock of the mine's presence.
The findings illustrate a complex reality for reindeer herding in the modern era. While the Kevitsa mine has undeniably changed the local environment, blocking migration paths and eliminating specific grazing grounds, the herders have adapted. The reindeer themselves show a remarkable ability to adjust their behavior based on the season, avoiding the disturbance when they need to protect their young but accepting it when the need for food becomes urgent. The study concludes that while the mine has caused significant local changes and increased the workload for herders, the combination of flexible animal behavior and human management practices has allowed the Oraniemi district to maintain its way of life in the shadow of the mine.
Drowning in papers in your field?
Get daily digests of the most novel papers matching your research keywords — with technical summaries, in your language.