T. S. ELIOT SAID April was the cruellest month; he clearly knew nothing of life on the river in March. For most of the river creatures there is no easy living. Food is short and body reserves at their lowest ebb. The valley looks desolate; hardly anyone or anything ventures out. Nearly every form of fishing is closed. The trout keep hidden, the grayling move into spawning mode and even the pike are out of season.
Occasionally a salmon angler will tough it out, but you can tell it is a token visit. A day to breathe damp air and get out of the house. The chances of catching an Evitt salmon are so remote as to be infinitesimal. The catch record book goes back over a century. Admittedly the entries are sporadic and in some years non-existent, but nowhere can I see a March salmon recorded. I would say that it is an exercise in hope over expectation, but even that overstates the expectations of these few, solitary anglers who know in their heart of hearts that the arrival of salar from the sea is still months away. But they do it because sometimes it is enough to stare at the ever-rolling stream, be a part of it by fishing and dream of better days to come.
But however foul the weather, bleak the outlook or miserable the work in prospect, I treasure March days. These are the last when I will have the place to myself. Once the fishing season starts in April people intrude on the landscape. Is that selfish? Probably. So every dawn morning that breaks bright and clear is mine. The valley stretches out for miles in every direction. Distant church spires usually hidden by trees poke up on the horizon. The gentle rise of the land from the river, across the meadows and on up to the denuded woodland, in most months obscured by the hedgerows, is for once apparent. The course of the river, in summer rough-edged by overflowing vegetation that tumbles from the bank, is now bare. The join between land and water is perfectly delineated, the river looking wide, clean and powerful as it drives through with winter pace.
The time has come for me to make the final push to prepare the river for the season ahead. The jobs I prevaricated over or simply put off for no good reason loom on the calendar. Banks to repair, fences to mend, fringes to cut, fallen trees to clear, potholes in tracks to be filled, machinery to service, sluices and hatches to tweak to get the perfect flow. No single job in itself critical, but as a whole the work that will make Gavelwood a better place for the creatures who watch me go about the daily tasks.
If you were that barn owl that I see taking a dusk or dawn hunting flight across the landscape of the chalkstream valley you would be very aware of how the landscape changes beneath you every few yards, the changes radiating out from the river. Ecologists call this cline. The dictionary definition is ‘a continuum with an infinite number of gradations from one extreme to the other’, which translated into the life of Gavelwood describes the change from the extreme wetness of river margins to the dry woodland well above the water table. As that owl you care little about how wet or dry the ground may be; after all you barely touch it when you swoop on your prey. Nor will you care very much about the vegetation that grows from the ground, be it tall green stuff in the wet or the stubblier, shorter growth in the dry. All you will know is that with each gradation there is a different type of small-scale habitat that holds a different meal from furry field mouse to slimy toad, with everything in between. It is this cline, created first by nature but now cosseted by man, that makes the chalkstream valley so extraordinarily diverse.
I start my March list of jobs on the riverbank cutting down what is generally referred to by river keepers as the ‘fringe’, which is the swathe of growth along the bank that separates the river from a mown path. In summer this is the most amazing collection of native plants, with names that are fantastical: reed sweetgrass, comfrey, fleabane, marsh woundwort, ragged robin, hemp agrimony (Latin name Eupatorium cannabinum, so no prizes for guessing its origins) or hemlock water dropwort to name just a few of the common ones. They are not dull plants to look at either. Each meadowsweet has a host of fluffy flowers that look like lamb tails. The water avens is reminiscent of the purple fritillaries that are lovingly nurtured in the ‘wild’ sections of formal gardens. Comfrey, with elongated bell-shaped flowers in white and purple, is a magnet for bumblebees.
The river fringe is, believe it or not, one of the hotly debated aspects of river management. Every keeper harbours an opinion. Some like it narrow, maybe a foot wide and trimmed short to knee height. Others like it wild and wide (up to 2 yards), with just the worst of the excesses trimmed off. Which is right? Well, at either extreme neither does the job properly. Cut back to nearly nothing it deprives insects and wildlife of a home along the river’s edge. Left to run wild, the dominant, invasive plants crowd out the others and fishermen cannot reach the water. The one thing everyone agrees on is that March is the time to cut back the dead growth from the previous year, but even then it is no scorched-earth regime. The riverbank, with all its chaotic growth that tumbles over into the water, is the vital connection between the river and the valley through which it flows. For the creatures it is many things; a home for a nest, a profitable hunting ground, a handy staging post when moving from the river into the meadows beyond.
Cutting, even on a cold March day, soon works up a sweat; it is surprising how much force you have to exert to swing the brush cutter through the tough stems of the tall, spindly dead plants and matted grasses. As I took a break sitting on a stile I saw the layer of newly cut stems start to move and suddenly this little face popped up from beneath. The ears, disproportionately large for the head, swivelled in my direction, assessed me for what I was (no threat) and disappeared beneath the cuttings. Clearly on a mission, I could trace the stop–start zigzag progress of the field mouse as he made his way along the bank by the movement in the cuttings. My work had created an unexpected bounty for Apodemus sylvaticus – wood mouse, or long-tailed field mouse – at an important time of year, as the mice are just getting into the breeding season. The bounty is all the seeds dislodged by the cutting, and the mice were soon out in force, scurrying around to eat and gather as much as they could.
The field mice are funny little things, I’d hazard the commonest mammal at Gavelwood – they are nearly everywhere. Along the banks, all over the meadows, in the hedgerows – about the only place you won’t find them much is deep in the woods. Every day I will see them scampering or hear the rustle of the dried grass as they head for cover. The food they eat is an everyday staple of the valley – seeds, fungi, worms, tiny insects and even snails. I am no threat to them and today I am their saviour. Despite the noise, commotion and fuel fumes from the cutter they almost get under my feet in their eagerness for this unexpected feast. Once they have eaten their fill they start to carry off twigs to build the nest for the first litter of the season that will shortly be born. It’s a pity that not all of them will make it. Though I see plenty of field mice during the day, they are mostly nocturnal creatures. The huge black eyes are adapted to suck in as much light as possible, the ears attuned to every sound, and the pointed nose has a sharp sense of smell for locating food. So far so good, but the one device they lack is radar, and that is a shame, as their greatest enemy comes from the sky in the form of my dawn hunting companion the barn owl, whose night-sight trumps that of the field mouse.
Barn owls just drift across the valley. There is no hurry to their lives. Bats are frenetic, raptors tense and ready, but owls take it all very steady, wings stretched out on the air with head down scouring the ground below. If they make the stoop for a successful kill, they head off, the victim dangling from the beak, with no sort of triumph, to share the spoils back at the nest. If they miss out they’ll just perch on a nearby fence post or tree branch for a while, then resume the hunt. I have no idea why barn owls are so languid. Maybe it is because with so much food on offer most times of the year (water voles, baby rabbits and shrews are always on the menu) they have few worries about starving. Tonight they certainly won’t. I know for sure that at dusk the newly cut bank, now a magnet for the field mice, will become a corridor of plenty for the owls. That is the thing about managing a river; one action brings many reactions.
Sometimes I don’t spend enough time taking a really good look at the entire length of Gavelwood, but a few days’ bank cutting seems to be nature’s way of imposing some discipline on me to gain a better idea of how every yard has coped with the winter. Chalkstreams are not like big spate rivers where exceptional floods can move boulders the size of a house or cut a completely new path for the river. The changes are more subtle and gradual. A fallen tree may have redirected the current. A bank collapsed after years of unseen erosion. If we have had a dry winter the riverbed will have silted up in places for lack of a flush.
Yard by yard I take it all in. There is not much insect life on the surface to distract me; an occasional hatch of midges, but it is fleeting. Sometimes if the sun shines for a while around the middle of the day there will be a hatch of large dark olives. The fly-fisherman in me will instantly perk up at the sight of these up-winged flies, with their brown camo body and translucent veined wings that catch the sun’s rays and positively shine as they bob on the surface. These are the type of flies that trout like to eat, not the biggest a trout will see in a year, but ten times bigger than the midge option. If the trout start to rise I curse the fact that the opening day is still some weeks away, though in truth with the adult trout pretty well dormant the olives will usually go unmolested unless Scar Boy and his fellows in the shallows get a taste for them. The real March action is under the surface.
Assuming that the water in the river remains at a fairly constant temperature all year round, which it does, it is a fair question to ask by what calendar the insects measure their year. What is to stop a caddis nymph, a fly that usually hatches as sedge in July, mistaking a hot April as the right time? Why is it that every fishing record book going back centuries notes the start of the mayfly hatch on the chalkstreams in the second or third week in May? Across those centuries the months leading up to May have been wickedly cold, exceptionally snowy, the driest since records began – you name it, those extremes have happened – but still the hatch comes bang on time. It is tempting to think that it might be a particular weather window that triggers the hatch, but Ephemera danica emerges just the same on a cold and squally day as on a hot and sunny one.
The explanation lies in the length of the day, the time from sunrise to sunset and the associated light intensity. This is the one constant for the past few million years, and the chalkstream insects have been there pretty well right from the beginning, or at least 318 million years according to fossilized mayfly remains. So whatever the weather, the sun has always risen at the same time and set at the same time, and this is the calendar to which the insects attune their bodies. March might seem a mostly miserable month for anyone on the riverbank; for the aquatic creatures they are already closer to the longest day than the shortest, where under the water they are evolving in a steady progression ready for their big day. That day can be anything from a few months to two years from the moment that the spinner, the egg-laying female, dips down to deposit her eggs on the surface of the river. For the ubiquitous midges that I see hatching every month of the year, the cycle from egg to nymph to midge is two months. For the mayfly the same cycle is two years, and when my March companion the large dark olive finally breaks surface it is the end of a six-month evolution.
Try as I might I have never seen olive eggs, or any other insect egg for that matter, in a river – they are so tiny as to only be observable through a microscope. It seems incredible that something so small can withstand the drift downriver until the sticky eggs randomly attach themselves to the gravel, weed or river plants. But they do survive this tumbling lottery, and in great numbers. There are a few concerned parents like the Baetis species who take the trouble to crawl down into the water using aquatic plants as a ladder so that they can lay the eggs directly on something in the river, but these are most definitely the exception rather than the rule. Our dark olive is one of these fortunate offspring, but as soon as he hatches from egg to nymph, like an ungrateful teenager he will abandon his birthplace and spend his days darting from stone to stone or flitting amongst the cover of weed beds. As he grows he constantly moults, bursting out of one old skin after another, getting larger every time. Food is easy to find. The stones and weed have a slimy covering of algae, a community of tiny plants that the nymph can graze at will. Not all his fellow nymphs are quite as peripatetic. Some, like the mayfly nymph, tunnel into the silt. Others fall into the categories of silt crawlers or moss creepers, which fairly well sums them up, or there is a select group who spend their entire nymphal life clinging to a stone until the day they launch themselves towards the surface.
Whatever the habits of a particular nymph it is around this time of year that their abundance in the river starts to soar almost exponentially as they moult and mature ahead of the prime hatching months of April to July. For the chalkstream angler there is definitely a sequence to tick off as the season progresses: the large olive in March, grannom in April, mayfly in May, pale watery spinner in June, blue-winged olive in July, and so on. But this list does no real justice to the huge diversity of insects in the river, probably running to thousands, which are not only an entomologist’s delight but a feast for the fish for which nymphs and the other underwater creatures make up nine-tenths of everything they eat. For the angler who prefers the dry fly, imitating the hatches of insects alighting on the surface, this is a salutary statistic.
Trout and all the other fish in the river like nymphs for two reasons: there are masses of them and they are easy to eat. For us standing on the bank looking into the river, the vast population is hard to see, but run a fine-mesh net through the water or turn over a stone and a whole new world is revealed. Nymphs are everywhere, and if they were larger, say even the size of a mouse, you would throw the net down and run screaming. Up close they could be prehistoric monsters, given that they have barely evolved in hundreds of millions of years. They have a segmented body and six articulated legs, overall a bit reminiscent of a scorpion, but without the curved tail. The head is bulbous, with large wide-set eyes like a housefly, with a powerful mandible. At the back, three tails give it a total length of anywhere from an eighth of an inch to over an inch. The crawlers, creepers, clingers and diggers have strong legs, but the swimmers don’t, propelling themselves through the water by wriggling up and down like a person executing the butterfly stroke.
For the trout it is these swimming nymphs that they prefer to feed on, and once you know the pattern it is a fascinating little cameo performance. Nymphs are too small and not enough of a nutrient hit to be worth chasing after, but with so many to feed on trout would be foolish to ignore them. So look for a trout sitting horizontal in the water, facing directly upstream. Every so often he drifts to the left or the right, opens his mouth, swallows and returns to his holding spot. That is a trout feeding on nymphs. The key to the observation is the mouth, which shows out bright white from the inside when opened. This moment is what the famous river keeper Frank Sawyer, also the inventor of the most successful fly of all the time, the Pheasant Tail (a nymph imitation), described as the ‘chink of light’. If you are fishing, that moment of the ‘chink’ is the time to raise your rod tip and strike before the trout works out that your imitation on a hook is not the real thing and spits it out. The clingers, burrowers and crawlers may mostly escape the attention of the trout, but there are plenty of other open mouths ready to take these on.
The term ‘biomass’ is regularly bandied about by environmental scientists; it is an ugly phrase used to describe the total weight of all the fish in the river, from largest to smallest; at Gavelwood, among the regular inhabitants that would go from pike down to sticklebacks, plus everything in between. Counter-intuitively, it is one of the smallest of the fishes, the bullhead, that accounts for a quarter of the fish in the river by weight and an even higher proportion by numbers – only the sticklebacks are more populous. Faced with these sort of numbers arrayed against them, the clinging and crawling nymphs have a tough battle for survival.
For a fish so common, you’d think that the bullhead would be easy to spot: after all it is hardly what you would call microscopic, growing as it does to 5 inches, though more commonly 3. It is also pretty distinctive, unlike any other river dweller, with a blackened, flattened head, reminiscent of a bruised miller’s digit after it has been caught in the grinding mechanism (ouch!), giving rise to its other name, the miller’s thumb. The truth is that of all the fish in a chalkstream it is the one with the best camouflage and the most inconspicuous lifestyle, living as it does under stones, only coming out to feed at night. Perfectly adapted to life in a fast-flowing stream, its large pectoral fins create downforce to hold it steady on the bottom; the nymphs under and around the gravel bottom are easy pickings, but really everything from tiny fish to their own eggs is fair game for which they compete fiercely with their fellow bullheads. They have a terrible reputation with river keepers as devourers of trout eggs, but they are as much sinned against as sinners. At certain times of the year trout will eat nothing but bullheads, providing 80 per cent of their protein needs. Kingfishers devour them for a pastime, as do pike and herons, who are clearly all ignorant of the international conservation status of the bullhead that puts it on the same level as the Atlantic salmon.
All in all, life in the chalkstream food chain is not without risk, which might explain why the smallest of them all, the stickleback, is the most aggressive of them all.
The three-spined stickleback (Gasterosteus aculeatus) are the fish of our childhood, the ones we netted from ponds and ditches, displaying them proudly to our parents in jars as they darted hither and thither clearly angered at their sudden relocation and confinement. For a stickleback does anger, along with vanity and courtship, quite unlike any other freshwater fish. For a start it is armour-plated, far tougher than any river fish needs to be. Its skin, and for that matter its general appearance, is closer to a tuna than a trout. Along its back, instead of a dorsal fin, there are three wickedly sharp spines, from which it get its name. Just above the head there are three more spines, two facing forwards and one back, and to complete the top, front and bottom array of weaponry it has a final short, sharp spine under the belly. By early summer the warm back eddies of Gavelwood will be thick with schools of inch-long sticklebacks, flitting together in a swirling ball. But wind back to March and it is a very different story.
The mating ritual of both trout and salmon, however selective choosing the mate may be, looks a cursory affair, with little courtship or sense of occasion – some might say it is cold-blooded. However the stickleback is very much the Casanova matador, dressed up in finery that sets him apart from every other fish in the river. He is as bright and dapper as the kingfisher, and the more the mating ritual progresses the more his fishy plumage glows. The start is to carve out his territory; there is no great science to this. He picks his square foot of riverbed and then protects it jealously from all comers. When it comes to territorial protection this is not the subtle style of war. Our male believes in the full-frontal approach, swimming fast and direct at the invader. If they do not retreat he stabs at them with his spines or bites them. The more he wins the battles, the brighter grows the hue of his silver/green flanks. The pale pink blush under his throat goes a bright red. Badly injured invaders slink off, visibly turning grey in defeat.
The territory secured, it is time to build the love nest. Using his spines as forks, the victor rolls around in the riverbed to create an indentation that he now lines with short lengths of reed or twigs that he binds together by secreting a slimy mucus over them. The floor finished, he adds sides, one end and a roof. The nest complete, a tunnel an inch in diameter and about 3 inches long, it is time to find a mate. This involves lots of swimming around in front of prospective wives; presumably his super-bright appearance indicates that he is a valiant fighter and successful nest builder, so soon a female will peel off from the group and the male will usher her towards the nest. Once inside she will lay a few eggs, indicating her success by breaking through the end wall and swimming away. The male will follow into the nest, cover the eggs with milt and then stand guard until the following morning, maintaining his routine of feeding and attacking all comers. The next morning the whole courtship process resumes, culminating with more egg-laying and milting. Whether it is the same female every time who can tell, but after a few days, when the male decides he has sufficiently filled the nest he boards up either end.
You might think that this marks the end of the stickleback’s paternity interest – after all every other fish in the river abandons the eggs, and usually without this level of protection. But not the stickleback. He stands guard for anywhere between two to three weeks whilst the eggs hatch. Although it might be tempting to think that standing guard is superfluous, should he meet an untimely end other sticklebacks will shred the nest and devour the contents. But assuming all goes well, dad will keep the newly hatched sticklebacks confined to the nest, chewing up food for them to eat, and at around a week old he will dismantle the nest, the family living in the ruins for another week under his guardianship until they gradually start to disperse.
Over the years, the more I see the sticklebacks the more I have come to admire their sheer determination to perpetuate the species. I guess being so small you have to try that much harder, and stay small they most certainly do. Most fish keep growing if the food and habitat allow it: pike to thirty or forty pounds, trout to six to ten, grayling to three. But the little stickleback remains in that fraction-of-an-ounce territory however abundant the food or good life gets. It could just be that nature recognized that with his warring lifestyle and pumped-up body, if he got any larger he would wipe out every other fish in the river. Yes, the stickleback is best kept small.
By the end of March there is just a hint of spring about Gavelwood; a very slight hue of green to the trees and hedges. Some of the woody plants, like nettles and hogweed, are pushing up shoots along the riverbank where the relatively warm water keeps the frost at bay. But it is the water in the river itself that is my greatest concern. Such is the nature of a chalkstream that for good or ill, by this moment of year the die is cast for the next six months ahead. Great, bad or indifferent, with one look at the river I can predict the season to come, and it is all down to the unique geology that feeds water to the chalk rivers.
Chalkstreams are not confined to southern England as is often supposed. Yes, the most famous and the majority of them are crowded into Hampshire, Wiltshire and Dorset, but they flow in the continuation of chalk strata that starts north of Hull in East Yorkshire. The seam heads down the east coast, goes briefly into Norfolk and then turns southwest, skirting London across the Chilterns and then on towards Southampton and the Jurassic Coast, where it dives beneath the Channel to re-emerge in Normandy. Here the Risle, the Charentonne and the Andelle are the epicentre of French fly-fishing, the traditions, styles and hatches of England reproduced with a Gallic twist. Charles Ritz, he of hotel fame and mentor to Frank Sawyer, made them famous in the post-Second World War era, and it’s the only place I’ve heard of Hemingway fishing a chalkstream.
It seems an obvious thing to say, but chalkstreams are unique and special not because they flow through chalk land, but because the water in them has come from a natural chalk reservoir deep beneath the ground. Put at its very simplest, the water I watch flow by in the Evitt today fell as rain months ago, on downland many miles away. That rain filtered into the earth, eventually finding the chalk seam that is thousands of feet below ground. That seam then heads towards the sea, and as it does it gets closer to the surface until the water breaks out into millions and billions of springs that gather to create the stream. The geology of the process is, inevitably, more complicated than that. In some river catchments, the journey from raindrop to river water lasts just a few miles and a few weeks, but for most it is months or years. So think of the chalk as a giant sponge and you are some way to understanding how the process works. Take that dry sponge and gradually pour water into it. For a while the sponge will keep absorbing the water until at some point you have saturated it. From now onwards, for every new drop you pour in an equal amount will flow out. That’s how it works.
I am no soothsayer; my confident prediction for the season ahead is based solely on the rain that has fallen over the winter. There is an old saying in river-keeper circles that the only good rain is the rain that falls before St Valentine’s Day. This crude but effective rule of thumb is underlining the truth that the rain that falls in, say, May will only reach the river in October, by which time the season is over. The future is governed by the past – one drop in, one drop out.
Of course one dry winter is not a disaster. If that was the case the chalkstreams would have vanished long ago. There is enough tolerance in the geology to cope with the regular variations of the English climate, and sometimes after such a winter you would be hard pushed to see any change in the river over one summer. The water will be as pellucid as ever, the insect hatches follow their regular timetable and the trout go about their daily business. The real change will be to the velocity of the water as it pushes downriver, which will gradually slow without the aquifers pumping away at their normal rate. Think of it as turning the tap on your garden sprinkler down half a turn; appreciable but not critical. That is the effect of a single dry winter. But turn it down another half-turn, then another, and keep up the half-turns until the point at which the sprinkler stops working, then you would have the effect of successive dry winters or abstraction by man – a river that gradually stops working.
But chalkstreams are amazing things; freaks of nature that have survived thousands of years with water so pure and so clear that put in a glass it is as good (or better?!) as anything you can buy in a bottle. Every day millions of gallons flow up from the aquifers, down the rivers and into the ocean, and in that fleeting journey create a home for a unique collection of creatures that simply would not exist as they do without that water. However, all rivers are fed by rain or something similar like snow melt, so what makes a chalkstream so different? In the end it is that slow release mechanism of the chalk sponge that makes the difference, filtering, changing and chilling the water. That filtering effect through the tiny fissures in the chalk is critical for creating the gin-clear water, free from any soil or particles in suspension. As the water touches the chalk its pH changes from the slightly acidic quality of rain to the alkaline of the finished chalkstream water, and after its time deep underground the water emerges at a cool temperature just perfect for trout and the invertebrates. Over the years, the more I have come to understand how chalkstreams exist the more amazing and special they become, but they can only exist today because a long, long time ago two events occurred, entirely unconnected and 50 million years apart.
The first event was a slow burn, lasting 20 million years during the wonderfully named Cretaceous period. England was beneath the sea for all this time, and as layer after layer of dead seashells and tiny marine plants were compressed and crushed, the chalk seam was created. As the water retreated the land emerged, but what it left behind was nothing special. It took the second event, the shock waves from movement of the tectonic plates that forced the Alps into being 15 million years ago, to remodel England with those rolling hills, the downs, that now capture the raindrops. Even after all this geological upheaval there were no rivers, chalkstream or otherwise. It took the ice age that ended around 9000 BC to put the finishing touches to the landscape, but we are still some way from the creation of the River Evitt and its like.
After the ice age everything became incredibly wet and covered in woodland, a sort of English rainforest if you like. But still there were no rivers; it was just a swampy landscape into which came a creature, extinct in Britain today, whose dominance would result in creating the rivers. That creature was the beaver, a mammal whose obsessive dam-building gradually turned rivulets into rivers. As the swamp retreated the Iron Age people began to clear the woodland to cultivate the fertile valley soil, and around the time of Christ the first water-powered grinding mechanism came into being. To call it a watermill would overstate its influence on the river landscape. That change was left to the Romans who imported their considerable expertise to harness the power of water, and it is probably due to their legacy that a dozen or more mills are recorded in the Domesday Book for the River Evitt alone – there would have been thousands on the chalkstreams all told, and from this point onwards the valleys began to look something like they look today.
And as for today, the last of March and the day before the fishing season starts, I have every reason to be hopeful for the spring and summer ahead. The winter was wet, the work is done, and as the landscape sheds its winter veil I take a last turn around Gavelwood to check that all is well. Tomorrow I return as a fisherman.