In the Sussex countryside and our local parks one can easily imagine being in a semi-arid region of Portugal, or North Africa. Never in my lifetime, or indeed most of our lifetimes, has there been a summer like this. So far, 2022 has seen the driest first half of the year since 1976 and, in some areas, the lowest July rainfall on record.
There has been rain, and some relief, recently from the record-breaking heatwaves, but reservoir levels are well below average and up to 50% of some crops may be lost to dry-as-a-bone drought conditions.
But while rivers dry up and private water companies reluctantly issue hosepipe bans (having failed for decades to invest adequately in infrastructure), in a few small pockets of the countryside long-term resource management is being done properly, and water is abundant.
All thanks to the beaver.
There are now over a dozen licensed beaver reintroduction trials in enclosed sites across England and Wales, plus expanding wild populations in Scotland and the River Otter catchment in Devon.
Recent images and updates from these sites make for a stark contrast with the baked ground and tinder-dry fields elsewhere, instead flaunting extensive ponds and saturated soils. This includes the National Trust site on the edge of the South Downs, where a pair of beavers was reintroduced last year. And less than six months since a new beaver pair was released on the Knepp Estate, near Horsham, they have radically transformed the habitat of their enclosure.
Unlike water companies, beavers have no shareholder dividends to maximise. They just like the security of deep water, where they can escape from predators and store caches of woody vegetation to feed off during hard times. As a result, they’re highly efficient ‘ecological engineers’. By building dams of wood, stones and mud across narrow channels of flowing water to flood the area upstream, they create an intricate carr wetland made up of ponds, riffles and canals.
These may flood nearby clusters of trees, leading to an increased availability of standing dead wood, a rare and valuable habitat in manicured British landscapes. The ponds provide niches for an array of species, from aquatic plants and insects to fish, birds, bats and more. After a reintroduction of beavers to an enclosed area near Okehampton in Devon in 2011, amphibian numbers skyrocketed, with surveys counting 370 clumps of frogspawn in the spring of 2014 compared with just ten in 2010.
Water released more slowly
Crucially, beaver wetlands buffer against the extremes of flood and drought. They form large stores of water, which is released relatively slowly as it leaks through the dams. And so, during droughts, beavers make watercourses more resilient and less likely to run dry. While the National Farmers’ Union likes to complain about beavers, their presence could in fact provide a crop irrigation lifeline.
And our beneficial beavers help too in the aftermath of drought, when flood water from storms flashes off the surface of soils baked hard by heat. Their dams reduce the impact of this, again by intercepting the flow and releasing it slowly. Research from the Devon beaver project found substantial reductions in peak discharges of watercourses downstream from the site where they had been reintroduced. There were increased lag times between peak rainfall and peak discharge.
So the widespread presence of beavers in the landscape can help to break the cycles of drought and flash flooding that are increasingly likely as the climate crisis unfolds.
Improved water quality
And it is not just stable water volumes that beaver activity provides. It also improves quality. The same research from Devon found significantly reduced concentrations of suspended sediment, nitrates and phosphates downstream from beaver dams compared with upstream. They can therefore mitigate soil erosion, agricultural run-off and sewage dumping, which are responsible for most of the river pollution in the UK.
And beavers could further indirectly improve water quality by boosting aquatic biodiversity. For instance, tadpoles feed largely on suspended phytoplankton (algae). Increased tadpole biomass, such as in beaver wetlands, leads to greater control of primary productivity and reduced concentrations of phytoplankton, representing a potential to mitigate algal blooms caused by nutrient overload.
Of course, beavers aren’t a silver bullet or a reason to abandon demand for fundamental change. A publicly owned industry, for instance, would reinvest profits in fixing outdated and leaky infrastructure so it didn’t haemorrhage over 3bn litres a day, and we wouldn’t have to feel guilty about flushing the toilet. But as a relatively easy contribution, bringing back the beaver is a no-brainer.
The government has made one move in the right direction: in July it introduced full legal protection for beavers as a native species, effective from October. This will facilitate ‘proper’ reintroductions into the wild as opposed to enclosures. But the ministry responsible, the Department for Environment Food & Rural Affairs (Defra), must stop dragging its feet and set out a detailed strategy, including a more streamlined licensing process.
In our new world of climate instability, this is one small but important step to ensuring that we – and the beavers – keep England’s land green and far more pleasant.