The Fence That Changed the Arctic Landscape: Reindeer, Lichens, and a Border Story

Hey There, Arctic Explorer!

Hey there! Ever wondered about those quiet, vast landscapes up north, like where Finland meets Norway? Me too. There’s this fascinating story unfolding right along the border fence, a story about reindeer, their favorite snack (lichens!), and how a simple fence built decades ago created a wild difference in the scenery. It’s a bit of a detective story, really, looking back in time to figure out why things look the way they do today.

The Mystery at the Border

So, here’s the puzzle: you cross from the Finnish side to the Norwegian side in certain areas, and suddenly, the ground looks different. On the Norwegian side, especially in their winter pastures, you find these thick, spongy carpets of lichen. Step over to Finland, and… poof. Much, much less lichen. It’s like night and day in places. This isn’t just a small difference; the study tells us the lichen biomass can be roughly three times greater on the Norwegian side today.

A Look Back in Time

Naturally, you gotta ask, ‘Why?’ Was it always like this? That’s where the clever folks behind this study come in. They went full detective mode, digging up old aerial photos from way back in the late 1950s, even older ones, and combining them with newer satellite images. It’s like creating a time machine with pictures! And guess what? Back then, right after the fence went up, the lichen cover near the border looked pretty similar on both sides. The big difference? It started happening after the fence was firmly in place and time marched on. Since the late 1950s, lichen cover has decreased on both sides, but the gap between Finland and Norway just kept getting wider.

More Than Just Munching

Now, your first thought might be, ‘Well, the reindeer just ate it all, right?’ Makes sense. Lichen is their go-to winter food, especially species like Cladonia rangiferina, Cladonia stellaris, and Cladonia arbuscula – the ones even named after reindeer in local languages! But here’s the kicker, and it’s a super important finding from this research: their fancy models showed that the amount of lichen reindeer *eat* doesn’t actually explain the massive decline they saw, not on either side. Turns out, it’s less about what goes *in* the reindeer and more about what happens under their hooves.

The Impact of Trampling and Loss

Yeah, we’re talking about trampling and other kinds of ‘loss’ that happen when reindeer are just doing their thing – walking around, digging for food, moving across the landscape. Imagine a delicate, dry lichen mat. A hoof comes down… crunch. Especially during the snow-free times, that trampling can be brutal. The study suggests this physical damage, this ‘wastage’ of lichen biomass, is a much bigger deal than just being eaten. In fact, their model indicated that the quantity of lichen lost due to these other factors was several times higher than the amount consumed!

The Fence Effect and Herding Practices

And this is where the fence really plays its part. Before the fence, reindeer migrated freely across this whole area. The fence, completed in the late 50s, stopped that cold. On the Finnish side, herding had to adapt to a smaller area, mixing up summer and winter pastures. Reindeer are there year-round. More time on the same ground, especially in summer when there’s no protective snow cover, means more trampling on those delicate lichens. The Finnish side basically became a year-round home, leading to constant pressure on the vegetation.

On the Norwegian side, they kept the traditional long migrations, using the area near the border only as a winter pasture. Snow cover is a great protector for lichens against trampling. So, even though the density of reindeer might be higher when they *are* there in winter, the lichens are somewhat shielded. The study even found a curious ‘negative fence effect’ right next to the fence on the Norwegian side early on – maybe reindeer bumping up against it, trying to get to old pastures, caused extra damage right there before they fully adapted.

Unpacking the Numbers (Simply!)

Okay, the science folks did some serious work here, using complex models and calibrating images from different eras – not a simple task! They had to figure out how to compare old black-and-white photos to modern satellite images to estimate lichen cover and biomass over time. They linked what they saw in the pictures to what they measured on the ground in small plots. Their model, which factored in reindeer numbers, lichen growth, eating, and other losses, really helped show that the ‘loss’ factor (like trampling) had to be much higher on the Finnish side to explain the observed decline.

They admit there are uncertainties in using such varied historical data, but the overall trend is loud and clear. The different ways reindeer are managed, largely dictated by that border fence and the resulting change from nomadic to more settled herding, led to vastly different outcomes for the lichen pastures.

What This Means

So, it’s a powerful reminder that even seemingly low-intensity land use, like traditional herding, can have big, long-lasting effects on fragile ecosystems like the Arctic tundra. It also shows that herding *can* continue even when lichen biomass is low, though that brings its own challenges for the herders and the animals. Understanding *how* reindeer impact the land – the trampling, the loss, not just the eating – is crucial for managing these landscapes going forward and perhaps finding ways to help these vital lichen pastures recover.

A Line Drawn in the Landscape

Walking that border today, you see more than just a fence. You see a line drawn through history, through ecology, and through the lives of the reindeer and the people who herd them. It’s a stark, charmingly simple illustration of how human decisions, even something as basic as building a fence, can reshape the natural world in profound ways. This study gives us a fantastic window into that process, showing just how important those delicate lichen carpets are and how easily they can be lost.

Source: Springer