One of the things I said in my chat with James Wallace of the beaver Trust that beavers can show off best in England is ecological impact with a baseline. As in our stream looked like this for years and years, then we added some beavers, and now it looks like THIS. But with statistics, so that scientists pay attention and people take it seriously. Apparently I’m not the only one who thinks so. This nice writing is from Joshua Harris of the Ecologist.
Bringing back beavers
We tend to overlook the effects that living organisms have on their physical world because most of the ecosystems around us have been “downgraded” as we have removed the important species – thus, in these cases it is mainly physical processes that determine how organisms survive.
But there is now an increasing weight of evidence that the interaction works both ways: the earth shapes life, and life shapes the earth.
Beavers’ engineering work benefits many kinds of wildlife: ponds are perfect for frogs and fish larvae, riffles and gravel banks for dippers, swampy areas for water rails and moorhens, dead trees for woodpeckers and owls, and lush coppiced vegetation for songbirds.
The fact that beaver habitat is ideal for so many species should not come as a surprise: beavers were present in our ecosystems for millions of years, so many wetland species may have actually evolved to live in beaver habitats.
Oh yes the beavers make the difference. And a stream without a beaver is like a car without a steering wheel. It will probably still go places. But probably not really the places you want.
Through studying the effects that beavers have on streams, it has become clear that deeply incised river channels disconnected from their floodplain, which we perceive as the norm, are in fact a consequence of the removal of beavers, and other human impacts.
Before we deforested and farmed the land and hunted beavers to extinction for their fur and scent glands, wetlands would have filled the bottoms of valleys, with snaking channels, ponds, wet meadows, and willow scrub.
By bringing back the beaver, and allowing our rivers to freestyle through the landscape, we could revive these incredible ecosystems. Beaver engineered wetlands could fan out into every valley in an interconnected network, like arteries pumping life back into the landscape.
So many other species could flourish in the habitats that beavers create: otters, water voles, marsh tits, spotted flycatchers, lesser spotted woodpeckers, water rails, egrets, lapwings, redshanks. Incredible species which we’ve almost forgotten could return – white tailed eagles, cranes, and even white storks, which last bred in the UK in 1416 but are just starting to make a comeback.
Be still my heart. The author of this fine blog entry is a young ecolologist at Cambridge. He volunteers with the beaver Trust and we are expecting great future contributions.
A revival of beaver ecosystems would have wider environmental and economic benefits beyond increasing biodiversity and bringing wildness back into our lives. Their leaky dams hold back water in floods, and release it gradually in drought.
By retaining water in the headwaters of catchments where the land is less valuable for farming, they could protect more productive arable land further downstream. As we experience more extreme weather events due to climate change, reintroducing beavers to our river systems could make a valuable contribution to reducing the damage to villages and towns.
The lush swamps that beavers create have been shown to filter out fertiliser and pesticide runoff, and reduce the washing away of soil to the oceans – something which is currently visible from space whenever heavy rain falls.
As vegetation builds up in the ponds it forms peat, and the carbon that was sequestered by the growing plants is locked away.
We’ve spent thousands of years trashing the complex connections in our living world, and we’ve created ecosystems which are a mere shadow of their former selves.
If there is one animal which we need in Britain right now, it has to be the beaver. The bang for your buck in terms of biodiversity and wider environmental gains is huge.
Gosh I like reading about people who are finding out how awesome beavers are by watching the difference they make for the first time. I believe it was Voltaire who wrote famously “If God didn’t exist man would invent him”. Very true, but I’m going to say if, by some chance, the UK hadn’t existed for 500 years without beavers we would have had to invent them, because they are SO DARN USEFUL at proving our point about why beavers matter.
Thanks Joshua.
