I know they’re down there somewhere, tucked in among the stones, as the muscular flow flexes around them. Their world has darkened and distended since the last time I visited. In May, after prolonged dry weather, plentiful small brown trout held within the narrow confines of this Dartmoor leat were easy to spot on the gravel bottom as the current ran clear and low. You could make out the attractive red ellipses patterning their speckled flanks.
Recent rain has now replenished the River Tavy, which feeds this old channel that once served nearby copper mines. The peat-stained river hurtles down the steep wooded valley, cascading over boulders, frothing and fizzing like cola. But water that is cleaved from the torrent and finds its way into this slender leat rapidly slows as the gradient eases. Within a short distance the surface is smooth as polished marble.
For the brown trout sustained by this capillary, the rain-fed surge has swelled their realm in a heartbeat. Full to the brim, it is too dark and deep to make out the bottom, or any aquatic life for that matter. All I see is a fleeting dimple as something rises to suck down a floating insect.
The spate river has added precious morsels of food to this liquid conveyor belt. The brown trout here never grow large, though, unlike those in lowland watercourses with more plentiful invertebrates. Fish several years old on Dartmoor seldom exceed a handspan in length. How strange it must be, I wonder, as I peer into the passing flow, to depend on such constant motion for your survival, as if spending every waking hour head down into a gale.
A short stroll downstream and the leat emerges from beneath oak trees and traverses open pasture. In places where livestock come to drink, sections of the stone sides have slipped. It is here that I finally see a trout – a tiddler, resting in the shallows, away from the rush, as if it’s pulled off the motorway for a break.
With a flick of its tail, it disappears back into the shifting depths. A shame to have disturbed it. Even fish need time out now and again.
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