1. In the past few days, we’ve seen a lot of disappointing statements about the natural world. Anger leads to resentment & passivity – but positive visions fuel us all. So here is a magical story of Beavers & Butterflies to get you through a damp Wednesday afternoon.
2. Once upon a time, a humble rodent set about making its home in a different way to its peers. Hewing waterside trees from the safety of the river edge (so it could avoid being snacked on by hungry wolves or bears), beavers evolved to become nature’s best hydraulic engineers.
3. As once impatient river waters clashed in frustration against the twiggy fortresses of beaver dams, new outcomes were born. Water became a film on the land; sinking slowly into the soil. Wetland meadows formed beside our rivers. Shade dwelt beside flower-filled light.
4. Butterflies, modern conservation tells us, require diverse ‘micro-habitats’ to survive. Many ecologists, whose profession is less than 100 years old, tell us that human are best placed to create these outcomes. But beavers have gardened for butterflies for many millennia.
5. The conservation movement is barely a century old. Beavers are older. They have managed meadows in our woodlands, glades, ponds, herbaceous coppice & wetland pasture for millions of years. But it can sometimes be hard to accept that a rodent knows best.
6. Once we do, and once we restore beavers to many of our wetlands, rivers and reserves (with the right to relocate them, alive, if they seriously misbehave), we will begin to see something miraculous. Butterflies forgotten to us all will begin to come out of the woodwork.
7. The large copper was once the beacon of our wetlands; burning bright in lush grassland filled with water dock. If this habitat dries out, coppers vanish. If it floods, its caterpillars wash away. Conservationists have tried to replicate what beavers do for free – and failed.
8. In Estonia, where the large copper (and beaver) is increasing, a beaver meadow is the best refuge of all. Dams, even old ones, holding and slowly releasing water, create the perfect damp conditions for these marshland rubies, now sadly lost to Britain, to thrive.
9. Older beaver ponds, slowly overgrowing with herbs, provide coppers with courting grounds. Alluvial soils fuel the growth of daisies, on which coppers spend much of their time feeding. The sunlit depressions of old ponds afford warm lush glades. A butterfly garden is born.
10. The high brown fritillary whizzes over woodland clearings, feeding in sunlit glades but laying its eggs on dog violets, which need moist soils to thrive. At great expense, we can create this habitat. A drying beaver pond restores this habitat for free.
11. In Wisconsin, lepidopterists have found that the Gillette’s Checkerspot, which fills a similar niche to our marsh fritillary, is tied to ‘cyclical habitats’ best formed where beavers are in charge. Americans are a long way ahead of us in some ways. We must listen & learn.
12. Back home, our chequered skippers thrive between shade & light; flickering between sunlit wet grassland & shaded woodland, requiring water trapped in the soil to grow its moisture-loving grasses. Described as a species of ‘rides’, who created those rides in the first place?
13. Wood whites flit like little ghosts through tall, damp herb-lands at the woodland edge. Such butterflies have habitats so strange and complex that perhaps beavers & their actions may best explain this species' evolution in the first place.
14. In a 12-year study conducted on the now imperilled beavers of Tayside, in Scotland, it was found that plant species diversity grew 50% higher around beaver ponds than elsewhere. The fine-scale woodland & wet meadows beavers create are almost impossible to replicate.