Spinners. I have no idea how they got their name. Maybe it describes the mating dance when the pair flies up in unison and then hovers for a moment at the top of the climb before relaxing their wings to spin down on the air. Maybe it is because in olden times people thought the long trail of eggs was something akin to spinning yarn. Or maybe it is the dead insect circling on the current. Whatever the reason the female spinner, ready to lay her eggs, is brighter than in her maiden form. Clearly the consummation brings colour to her wings and body. The egg-laying is a bittersweet moment to watch. On the one hand it is the proof that a new generation is on the way, but on the other that the insect will be dead in a matter of minutes or a few hours at most.
Some days on the river I will see one type of insect to the exclusion of all others, but today was one of those days when the diverse population was out in force; good news for the ever-hungry trout. There is not a lot of nutrition in a tiny insect, even for a trout, so it’s all about the effort/reward equation. A huge fat mayfly – the size of a dandelion head – is worth that extra effort, but the tiny corpse of an olive a gentle slurp. Somewhere in between is the impregnated female, stuffed with energy-rich eggs. The latter is so attractive to fish that fly tiers will add a tiny wrap of yellow thread to the underside of a fly – no more than an eighth of an inch long – to represent the egg sac.
There are dozens of species of fly to be seen. They make their lives on the river, but ultimately the eggs will be laid in one of two ways: on the surface or beneath it. For the angler and casual observer it is the surface layers that are the most interesting, especially the sedges. Sedges, or caddis, are big flies in the general run of a chalkstream. Not as big as the mayfly, but four or five times the size of your average olive. They are very much summer creatures, present beneath the current all year but hatching only in June, July and August. If they look like anything else, it is the common household moth with its wings folded in to create a tent over the body. If that sounds clumsy you would be right. Sedges are clumsy; the worst fliers and worse still at landing. Their approach to the river surface will look fine, but come the final few inches, instead of swooping gently down to clip the water to allow the surface tension to draw the eggs from her body, the female caddis will crash onto the water. Alerted by the commotion, trout from many feet away, even facing in the opposite direction, will turn and make a grab for the egg-laden wreckage. The smaller olives are, by comparison, incredibly delicate, getting within a fraction of an inch of the water before depositing their eggs.
For the angler tying on a sedge imitation this is a moment sent from heaven. There’s no delicate cast required here. No, a splashy cast will do as well, if not better, and the eager trout will do all the work to grab the fly. The olives are a different matter. You will need your thinnest line, your tiniest fly, your most accurate and delicate presentation. And even when you get it perfect, the languid trout, with time to weigh up all the options, will as often as not reject your offering.
It is relatively easy for the sub-surface egg-layers to go about their business unobserved, but the big problem is getting through the surface tension of the water. An insect with wings is quite bulky; it has a large surface area that is gripped by the water. Just sitting on the top and hoping to paddle their way underwater will not work. They need purchase and they find this from the reeds, stones and tree roots emerging from the water. As I pushed upstream on that July morning it was the perfect time of year for the blue-winged olive. And sure enough there they were with their drab olive bodies and translucent blue wings, arrayed along the length of the upright dark green reeds that gently swayed in the margin. Unfortunately there is an unusual predator that lies in wait.
As I watched the olive closest to the water edge down towards the film, and as she forced her body into the water, I could see the six tiny legs straining on the reed, the little suction caps on the feet giving her the leverage required. But in this moment of supreme effort it is the misfortune of the olive that the European eel chooses this very time of year to begin its downward migration to the sea. After ten or fifteen years in a muddy pond Anguilla anguilla heads for the Sargasso Sea, but before the ocean the river provides a welcome source of food. In the shade of the reed it is hard to see the eel going about his business, but in the early morning or late evening you will surely hear them. It is a slurping sound, a bit like a child sucking up the last of a milkshake with a straw, as the eel quite literally sucks the insect into his mouth at the very moment it is caught by the surface tension.
Fortunately there are many more olives than eels to consume them, so very soon the sunken spinners are laying their eggs beneath the surface. These then drift slowly down on the current to lodge in the stones, silt and general debris of the riverbed where they will remain for week or months until they become nymphs and embark on the next stage of life. I am not sure if the spinners themselves are able to hold their breath or even breathe underwater, but it probably does not matter. The time is short between submersion and being spent, namely eggs laid and becoming a semi-lifeless body, tumbling downstream on the current. The spinners that lay on the surface fare no better, collapsing exhausted on the surface, the job done. At first they lie on their sides, with one wing up, but as the life seeps away the other wing collapses and the end finally comes with convulsions that cause the water to ripple outwards around the insect until it stills.
Trout are no respecters of death, and sure enough, just off the main current, in a back eddy I came across a confident trout cruising in the slack water. With his back out of the water and his body submerged to eye level he languidly circled around, his mouth open, the flow of water carrying the spent spinners down his throat. This is the ultimate effort/reward equation and he keeps at it until the surface is cleared. Above him the duns, newly hatched, buzz in the air but he pays them no attention and the insect mortuary empty, he fins down to the deep to await the next funeral cortege.
A chalkstream in summer – June and July – is when it is most alive. It seemed that every step I took that morning, in the river or on the meadows, brought a new discovery. Above the shallows, on a dead branch, a kingfisher waited impatiently for the fry to move into the shallow water as it was gradually warmed by the morning sun. I am not sure kingfishers are really impatient, but the way they cock their head back and forth makes it look that way. I am certain the head-cocking is just to change their angle of vision so that they can see through the surface glare to catch sight of the fish, but for whatever reason, once locked in on the fry a rapid blue streak flashes from branch to water and back again in an instant. Holding the fish crossways in his beak the kingfisher raises his head, straightens his neck, turns the fry head-first and swallows it whole.
With a shake of his feathers, the watch will resume. This is likely to be an all-day affair, because the more the sun shines, the warmer the shallows will become and the more fry will appear in darting shoals. And the kingfisher is on a mission to feed. Somewhere along the bank, in a spot I was yet to locate, was a nest burrowed into the soft soil. In that nest would be maybe up to half a dozen chicks, each of which needs a dozen or more fish a day. That is getting on for a hundred fish. I watched our impatient friend catch four more and then left him to it, making a wide circle around the shallows to leave his hunting ground undisturbed.
By now the geography of the river and the meadows was starting to make some sense, and as I waded upstream the structure of the place began to arrange itself before me. The main river was the spine. Coming in from the left was a bourne, a small stream that only flowed in any significant sense during the winter and early spring, so by now was near to dry. It would remain so until the autumn rains. Cutting off at a sharp angle to the right, heading due north for most of its run, was a carrier, a channel dug by hand many centuries ago whose sole purpose was to flood the meadows from February to May. Now abandoned and choked with overgrowth, the carrier was clearly once pivotal to the water-meadow system. As the channel that moved the water out of the main river across the meadows it had leats or ditches that ran off at regular intervals on both sides as conduits for carrying off the water to flood the fields. But in an arid July the leats were dry and hidden by the summer meadow grasses. Come the winter they would reveal themselves.