Time to run. Autumn rain has flooded the cold tarn brim-full and the wind is bothering the rushes. Our green backs are now gunmetal black, yellow bellies silver, ready for migration. Mere striplings no more, we stop feeding, our guts shrink and gonads swell, skins thicken, pupils expand for the coming darkness, snouts grow sharper. Under a thin moon we leave the raw chill of the tarn that has been our home, its clear waters and sallow mud, and wriggle up the bank and onto the sodden land, a mass exodus. The ground is so waterlogged we can hear the air bubbles rising. We slither snake-like through the tall wet grass, the rain bouncing heavy on our backs, our sleek, muscled bodies undulating. Onward, onward. The growing years are over and we have waxed fat and long on the tarn’s bounty of leeches, shrimps, crayfish, minnows, molluscs and rotting flesh. The smell of river in spate floods our nostrils, the river that will take us to the sea of our birth to spawn and die. Spawn and die. Laboriously we writhe and shimmy overland till we reach the headwaters where we hurl ourselves in and surrender to the flow.
The river is brown with rain, tumbling and churning. Close to the river bed and away from the banks where rats and anglers skulk we race against time to get to the warmer waters downstream. By day we glide away from shadows of webbed feet and stabbing heron beaks, hugging the bottom, our pale bellies stroking the brown mud, we burrow into the bones of the river or we jostle for crevices in willow roots away from rat-holes or under a stone, but come the night we must go on, on, on. The night is our friend. Brown trout are travelling upriver to our old haunt on the moor. We outswim the rats, but an otter snatches one of us. Three of our number charge straight into a funnel-shaped net; they twist and coil, but their fins catch. We scatter away from the net and go on posthaste. Mayfly nymphs and caddis fly larvae shy away but our withered stomachs have no appetite. We waste no time foraging, only hasten towards our birthplace. We have one aim: spawn and die, spawn and die. We are driven, driven. Over weirs and eel passes we cascade, down to the lowlands and into the big river. Through peaceful country and cities with their irksome noise we swim, and more and more of our fellows join us from right and left.
Dawn-light gleams ahead, tree shapes emerge piecemeal and we hide under stones, in reeds, in roots where we lie leaden, making barely a ripple, sluggish until the fading sky spurs us on. With the night-comfort we revive and we are off again downriver, faster and faster, and all the while our gonads are developing, swelling. Our lives have purpose and no obstacle will hinder us. In the dark sump of the valley we plunge over waterfalls and jagged rapids, past pipes spewing brown slurry and foul yellow froth, into the bowels of a deep-cut gorge in the still of the night.
The river surges on towards the roar of a giant screw, turning, turning. A quandary, the light is coming, we slow down and circle, but in the end we must carry on, enter the chamber and glide over the floor under the deafening blades. The hard metal edge catches one of us, she flinches and ricochets and on the other side we see the scuff mark behind her head as she whooshes out like the rest of us, into fearful moonlight, but she falters, drifts on the current, her brain addled. A cloud of red billows. Below the turbine we swim under one big mantle of white scum, so thick we cannot see the moon, cannot tell night from day.
The river is drowsy now, and murky. It lolls through the flatlands, unhurried, unstoppable. Capillaries come to join us on all sides, bringing more of our number. We are legion, and when the sun rises we flee the clutches of long, narrowing nets. Those of us who stray into them knot and coil, wild, desperate, trapped. We skirt the grim spectre of pipes that spout foaming dross, and rafts of plastic bottles that mass in the crooks and meanders of the river. A whiff of sea fills our nostrils.
This is it. The river yawns into the sea. Bodies float by and thundering ships traumatise us but we must go on. We have passed under many bridges, but now comes the biggest of them all. We slow down to seek resting places, thinking the sun is rising, but it’s only the lights on the bridge reflected. Traffic roars overhead and we are glad to escape. Onward. We taste salt. Our stomachs shrivel at last to nothing. A cormorant dives off a rock, grabs one of us and carries it back to its perch, writhing and squirming and thrashing. In the sea-womb we speed up and join our fellows: from the icy north and from the mellow east they come. The nets here are massive. With the first gleam of light we turn and go down, down, vertically, away from the light and its terrors: whales, sharks, crabs, gulls, propellers. But come the night we shiver into life, rise and aim once more for a warmer clime. A porbeagle shark take some of us, but we turn right into the narrow channel where the water rumbles and judders under the monsters that keep coming. On we go, on and on to the grey, heaving waters of the ocean where we hitchhike on the current that will take us back to our beginnings. On the night runs we scythe through the shallow warm waters, then down, down to the refuge of the depths at dawn. A squid lurks in the twilight zone with all-embracing tentacles but, whip-smart, we descend to the midnight zone, a black void with no vestige of sunlight where they seldom go. Back up we go when our bulging eyes sense the fading light above. We like dark. More join us from the north. There will be no more dams or weirs now, but predators abound: bigger fish, whales, sharks, turtle hatchlings, crabs, birds. Most of them linger near the surface, though even deep down our enemies wander. We spot them and scatter, but they dart and swallow us by the mouthful.
Storms blow up, but we shelter in the hush. A turtle thrashes and flails in a plastic bag. More shoals come from the east to swell our cohort. The water is warmer, a cosy tide on which we drift. In the belly of the sea we ride the deep-ocean currents and head out to the rocks where vents expel hot water and bustling communities bask. We are drawn by the warmth, fatally, because there too lurk those who would eat us, and do: dolphins, jellyfish, a giant whale shark gobbling everything in its path. Away from the hot vents we flee, too late. Brute nature will not deter us, but we are thin and tired, flesh dwindling. We hurry on. A giant tripletail approaches and we dart out of the way, but it is trying to crunch a yellow helmet. The thing is stuck in its mouth. The currents carry us away, and with every gleam of daylight we plumb the depths. Our ancient forebears had less far to go; we travel three thousand miles, and our northern and eastern fellows still further. Every year our birthplace drifts further away. Many moons have grown fat and thin since we left the tarn. Driven, driven.
At last we reach the doldrums, our grave and the cradle of our progeny. The clear blue water lulls us with its warmth. Spawn and die, that is our sole purpose, spawn and die. Through our nostrils we imbibe the salt upwelling from the ocean floor. The sea is calm like no other. Here in its sluggish swirl is rest, safety in the long, dense mats of floating orangey brown seaweed. Air sacs keep the snarled mass afloat, while foul-smelling dark brown shreds slump to the floor. We are not alone in favouring this tranquil sea as a nursery, and most of the countless young here match the sargassum in colour. Deadly sharks and tuna and marlin hang around the edges of the mats and pounce on creatures that emerge. And caught in the tangle is the plastic debris of humans: plastic bottles, blue and orange and turquoise and green nets and rope, triangular sandwich packs, a yellow mustard bottle, lighters, bottle caps, toothbrushes, broken crates, lids. A seahorse nibbles at a rubber Bambi. A triggerfish is trapped inside a plastic bucket, cannot turn round. Beneath the canopy of golden weed is a soupy layer of tiny plastic fragments which meander down like bits of rotting leaf. Slowly our males embrace us, poised, with a shudder we shed our eggs, millions of them, and they shed clouds of sperm. Our task is done. We sink deep, deeper into the dim distance amid the rain of plastic remnants.
