Every other day or so of late I’ve skipped the bus queues and hopped on a ‘Ready Bike’ to get down the hill to Reading station. The heavy-framed, robust machines pick up speed easily on the downhill, so at least part of the ride is quite fun. Unfortunately, traversing the urban landscape and dicing with rush-hour traffic is not so pleasant. Neither is the Reading townscape a peaceful or inspiring place to cycle. Even the River Kennet comes as a disappointment, surrounded by concrete walls as it slinks shamefaced through town, as though cowed by its encounter with the Oracle shopping centre. But is it fair to judge a river by its surroundings? Under the water, the Kennet lives. It’s far from perfect, I’m sure, but the freshwater environment up and down Britain is cleaner than it has been for a good few decades. One proof of that is also the reason I must remember not to cycle through Reading town centre with my mouth open at this time of year: mayflies.
As individual animals they’re quite beautiful, especially in the manner of their flight. Early in the month the first to emerge twirl slowly up from the water’s surface, inviting any number of doubtless clichéd comparisons with helicopters or ballet dancers. For me the delicate backlit twirls of the mayfly’s wings are spirals in time, spinning a thread that connects us to the long-ago age in which they first arose, before even the first dinosaur walked the earth. When numbers start to peak, the focus shifts from prehistoric individuals to mass spectacle. The most obvious mayflies on the Kennet are large, three-tailed species of the genus Ephemera. Seeing hundreds of thousands of these dancing above the river and resting on buildings and bridges throughout town must have at least some impact on even the most entomophobic of passers-by. It’s not everyday you see big numbers of sizeable, striking insects; in fact, it’s perhaps only close to water that we do at all nowadays. In any other part of the landscape the loss of natural abundance is overwhelming, an increasingly recognised* tragedy that Michael McCarthy calls ‘The Great Thinning’.
This past weekend I took a slightly more rural cycle ride east along the Kennet, starting in Newbury town centre and then making my way along the canal as far as the Thatcham reed beds. Mayfly numbers were now at an impressive peak**, with hundreds-strong hordes looping frantically up and down over waterside trees – moving much faster than those first few Reading debutantes – whilst others rested on low vegetation beside the bank. The odd party of black-headed gulls cruised through at just above treetop level, undoubtedly picking off a few mayflies each for an afternoon snack. Above them two hobbies scythed into view on sharp-angled grey wings, working with their red-trousered feet to pluck morsels out of the air. Too high to say for sure what they were grabbing at, but few dragonflies are on the wing yet so it seems likely they too were partaking of the mayfly bounty.
It’s obvious that waterways are corridors of sanctuary for wildlife, from the relatively undisturbed habitats under the surface to the hard-to-reach and thus untamed strips of wild, rank vegetation that line their banks. That’s not just for obviously wetland-dependent species: last week I saw a house sparrow sat on a Newbury rooftop holding two large mayflies in its beak. I’m sure it’s these and other aquatic insects that help to sustain a vibrant sparrow colony whose patch straddles bushes either side of the canal at the end of our garden. Corridors of life, corridors of hope: in an age of gloom for conservationists, the statistics are often frightening. But unlike with extinct species, the good news about lost abundance is that it is something we can at least partially bring back.
*Not just recognised but beginning to be backed up by hard evidence. Recent research by a group of scientists working in Germany suggests an average 80% decline in insect biomass, and their data is from nature reserves!
**Although, thanks to ‘shifting baseline syndrome’, I don’t really have any idea how many there ‘should’ be.