WETLAND REGENERATION: WHAT WE CAN LEARN FROM LARGE SCALE PROJECTS

If you build it, he will come.
Field of Dreams

As the increase in flooding in recent decades has shown, our rivers have become too straight and too fast, the banks are too steep and water runs off fields taking soil and nitrates to the sea, creating a cycle of destruction. Re-meandering our rivers to slow the flow and regenerating the banks and soils in fields to hold water for longer is vital to our collective health. Trees along banks cast shade for breeding fish and provide homes and perches for birds. Dropped leaves and branches add biomass to the water to help create healthy ecosystems. In time these become permeable dams, trapping sediment and pollutants.

If you want to re-meander, to remove a weir or construct a dam on a UK river you will need a licence, but it is possible, and many authorities are open to discussing improvements. (Details of where to get help can be found on page 230.) In the UK several projects in recent years have focused on slowing down rivers and restoring wetlands. It is one of our most valuable ecosystems, able to lock up the most carbon of any habitat, and accounting for 10 per cent of species despite covering only 1 per cent of land on Earth.

There are two main ways to do this. The first is being pioneered by the National Trust’s Holnicote Estate in Devon, where land drains have been broken, wide scrapes dug and the old narrow river channel filled in, to allow water to infiltrate the historic floodplain naturally. This will raise the water table and create multiple and diverse pockets of habitat as the water finds its natural course through the plain. To help create habitats, whole trees have been laid like horse jumps as obstructions, waiting to collect debris like beaver dams. The project is called ‘Stage 0’ as it returns the floodplain to its original stage before humans began to drain it for agriculture. Dr Richard Brazier and Dr Alan Puttock at the University of Exeter have modelled predicted flow and optimum ground levels, and baseline surveys are monitoring the species arriving, the level of water cleaning and flood prevention taking place.

Another project being guided by the University of Exeter with others is at the tiny headwater stream on the river Tamar, where a 900-metre (1,000-yard) fence created a trial beaver enclosure in 2011. It monitors the effect of these animals on the landscape and whether they prevent encroaching scrub from overwhelming the unmanaged grassland. As the image at the beginning of this section shows (page 68), the difference in landscape character and biodiversity is astounding. The beavers created highly complex, ever-changing mosaics of rich micro habitats and brought back rare water beetles, damselflies, dragonflies, frogs, newts and toads, plus kingfishers, water rail, roosting snipe, grey herons, willow tits, grasshopper warblers, black caps and willow warblers. As well as the excellent biodiversity and carbon capture, the ecosystem service impact really showed in times of recent drought, in stark contrast to the surrounding land, which was parched and suffering. This 3-hectare (7ó-acre) site now holds around 1 million litres (220,000 gallons) of water. As well as drought resilience it also slows flow during storm events, with results showing stormflow reductions of up to 30 per cent downstream.

At Spains Hall Estate in Essex, regenerative land steward Archie Ruggles-Brise has worked with local water companies and authorities to create wetland habitat and clean water with two beaver enclosures. By holding water in high-rainfall events, the new wetlands have reduced the historic flooding that their local village suffered, as well as increasing tourism in this rural area.

Beavers are herbivores; they don’t eat fish. They eat lots of willow (Salix), for which they were hunted to extinction in England, as the castoreum produced in their scent glands contains the medicinal silicic acid from willow (the main component in aspirin). They also eat herbaceous plants like the rampant watercourse colonisers Himalayan balsam (Impatiens glandulifera) and hemlock water dropwort (Oenanthe crocata). They can fell most types of trees with their iron-toughened teeth, to create habitat and to reach the succulent new growth on the upper branches. Once we understand how efficient and effective beavers are at creating useful and beautiful habitat, the questions become: why don’t we immediately introduce them everywhere? And why are farmers so wary of them?

It’s important to understand all concerns in this coexistence vision, and to know that most smaller farmers survive on tiny profit margins or are in debt to large agricultural input corporations, with rent or mortgages to pay on their land. Prey to uncontrollable weather and changing government ideology and paperwork, beavers can seem just another unpredictable factor in farmers’ volatile futures. The facts are that beavers will take down some unprotected trees, and they will eat unprotected carrot or potato crops near their homes if available. They may dam in inconvenient places or even burrow under roads. We can, however, learn to live with them and other future ecosystem restorers by looking to places that have coexisted with them during the centuries we lost to extinction. In Bavaria, Germany, each area has a volunteer beaver warden who liaises with farmers and landowners, educating, negotiating and, if needed, translocating or even euthanising their 25,000 beavers. Farmers are paid by the taxed community to leave a 9-metre (10-yard) riparian strip along water banks to prevent crop damage. Many find this a useful income compared to the tight margins on high-input crops. Key trees are protected with wire netting, and important infrastructure is constructed to be beaver-proof, with simple rebar construction on banks to prevent burrowing.

In the UK the Beaver Trust is helping to educate and increase dialogue with landowners and stakeholders, and Natural England, NatureScot and Natural Resources Wales are all working to advise ministers and influence nature-positive policy. All of us can help by being informed, by amplifying the messages and by supporting our wildlife trusts with money and time.

We are all an intrinsic part of nature and in our own gardens there are usually no beavers, nor bison, wolf, elk, wildcat or wild boar, so along with the bees we are the remaining prime ecosystem engineers. We reap the benefits of the ecosystem we create, through planting like a jay or squirrel or through disturbance, whether coppicing to harvest and maintain woodland or pruning roses like a browsing herbivore. Imagine you are rootling like a wild boar when weeding, rejuvenating and creating a little space for new growth, or building mini dams like a beaver to make water slow down and stay, bringing extra life to your garden. It is up to us to create a regenerative rather than destructive garden. Wouldn’t it be great if homeowners were incentivised to provide ecosystem services in our gardens. Council tax could be reduced for a Five Star Rated Garden that locks up carbon, reduces temperatures in summer, cleans water and improves soil health. Until then we can enjoy just being part of the solution.