To catch big trout, one must know when to cast and when to stay calm. As the mayfly season whips the fish into a frenzy, follow Charles Rangeley-Wilson's advice

The mayfly season is as fickle as the fish it frenzies, so follow Charles Rangeley-Wilson’s advice on how to catch big trout. Above all, forbearance is key – and don’t bother casting until after the lunchtime sandwich stop.

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If the mayfly hatch marks your only annual foray after trout and if your casting’s as rusty as my shooting and your fishing tackle positively vintage, it might be worth taking my mayfly MOT. I decoded the process last year [May 2018 issue] into a simple, affordable kit and foolproof casting practice.

I said that even the cheap rods are good nowadays – so there’s no excuse for using that knackered old garden cane – that a 25-guinea fly-line is all you’ll ever need, that you must use a tapered leader (ideally a roll-your-own) made of ordinary monofilament and attach it to the fly-line using a needle knot and nothing else, no matter who is telling you otherwise. Braided loops are the work of the devil.

Catch big trout

You want to hit the stream around four days after the mayfly hatch begins.

I said you should strap your bicep to your ribcage and the butt of the rod to your wrist and stand with your back to a hedge and thereby learn that if the elbow remains relatively still, and if the wrist doesn’t unhinge too wildly and if the rod stops at one o’clock on the backcast, then the line will go out straight and the fly will land, more or less, where you want it to.

Short of knowing where and when to go, you are ready to catch a whopper. The ‘when’, however, is not as simple as you’d imagine. Duffer’s fortnight is not a fortnight and, even if it were, it’s not the same fortnight everywhere. The mayfly hatches at different times on different rivers. It can even hatch at different times on the same river. The Avon round Amesbury is boiling over with cavorting trout by 15 May but the lower river doesn’t start cooking until the 25th. In Dorset, the River Allen is about two days ahead of the River Piddle: 12 May versus the 14th. But the Frome – just over the hill – is a fortnight behind both. Norfolk is a fortnight behind Hampshire. Yorkshire is behind Norfolk. Mid-May to mid-June throws a net over most of it but 14 June, say, could have you in the perfect place on one river or clearing up after the party on another.

More confusingly, if the hatch moves around the calendar from river to river in any given year, it also moves around the calendar from year to year. If it’s a warm spring, mayfly will be out a few days early. Just like daffodils and leaves on the trees. The hatch can come and go, too. In stormy, cool weather you reach mid-June and wonder if you blinked and missed it. Then there are years when I’ve gone down to the river in August and found mayfly all over the place. How on earth do you stick a pin in the diary and feel reassured that you won’t have missed the event by miles?

The best way, of course, is to move to a cottage by a chalkstream and wait until things look juicy. Bees are a good indicator, if you keep them. The moment they start mucking about swarming, leave them to it and head to the river instead: there’s a hatch on.

Catch big trout

Stick to open parts of the river if you cast in the afternoon.

If you have to book ahead, then, very roughly speaking, the mayfly advent calendar opens, door by door, in a south-west to north-east travelling fair. The starting gun goes off around 12 May in Dorset, a few days later in Wiltshire, a few days later still in Hampshire, and so on north and east until you get to Yorkshire at the end of the first week in June.

Don’t set off with that starting gun, however. Trout are wary at first of these drone-sized flies and will take a few days to tune in. When they do, that’s when you want to hit the stream – four days after the hatch begins, if the great fishing author JW Hills was correct, which I’m sure he was. If that coincides with warm, still and overcast weather, you’ll be in for a good day no matter what.

You’ll also be in with a chance at a true whopper. A monster mayfly muncher. Never mind the numbers, that’s what the mayfly season is really about, the few days in the year when the porkers come out to play. My angling pal, Ronnie, and I have honed this quest for a whopper into something of a religious obsession. As we get better at it the sizes of our conquests are slowly creeping upwards. Last season we both caught trout that were close enough to 5lb to call them that, in spite of the terrible weather.


Our secrets aren’t big ones but they aren’t that easy to follow, either, mostly because the main ingredient is forbearance and forbearance is not on the mind of the average mayfly angler fresh into Hampshire from the City on his only outing of the year. He wants to catch everything in the world and that usually amounts to arriving too early, walking up and down the bank too much and generally spooking anything bigger than a pound. But that same day when the fish go silly, when you could catch two dozen if you wanted to, will also be the day when the one resident lunker rises – perhaps the only time in the year – from whatever dark hole it normally eats minnows in, to sip delicately on the flotillas of mayfly duns.

Catch big trout

The main requirement for success is forbearance.

These fish don’t get big by announcing their presence, living out in the open for all to see, or jostling for scraps with the juniors. They live in the dark and secret corners, the places where food gathers in spiralling gyres, or where the meniscus is sticky and the flow is just a little bit on the lazy side.

There they lie, bellies grazing the algae, waiting. And waiting. And waiting. The hatch might have built to an apparent fever pitch in the air and on the surface above them but Cardinal Fatty doesn’t care. He’s waiting for the easy pickings, when it’s just right for a scoff. And it is hardly ever just right until… five o’clock in the afternoon.


That’s right. To get to the heart of what mayfly is really about, you’re going to have to book your expensive day and then wait until it’s nearly over. That might be a hard thing to do. I rarely manage it, so I’ll grant you a few hours sport in the afternoon, too, so long as you go easy and stick to the lively, brighter parts of the river. Leave the hatch-pool back-eddies and dark corners under alders for teatime. As for mornings, they are for reconnoitres only. Don’t even cast until after lunch.

If the dinner bell is five o’clock, it pays to be in position by half four. Our favourite spot is a canal-like reach on a little chalkstream in Dorset. From the foot of the run you can watch a long stretch of water upstream. Four or five enormous fish live in that ‘canal’, although for 348 days in the year you’d never know it. On about 12 May the mayfly start to hatch in dribs and drabs. The ‘canal’ remains as quiet as a grave. Two days later and the mayfly are really on it now, gunning their engines into life, rain-dropping the surface with delicate ripples. Still the ‘canal’ is silent.

But the next day, or the next, something will change and across the mirrored surface a rise-form will fan out and shudder into the reeds on either side of the stream. That’s when you know it is finally time to cast.

Catch big trout

The writer with a 3½lb Piddle trout.

Sometimes we have friends with us, sometimes not. Of course there are smaller fish to be caught upstream and down. You can fill your boots with pounders all afternoon long if you want to. Our guests – and I – often do. I’m not such a purist as Ronnie, who scoffs studiedly. But year after year, the 15 May rendezvous is the foot of the ‘canal’ at five o’clock, where Ronnie will say something like: “We’ve got a 12, a 14, a 17 and a 20.”

Our guest may not know what he is talking about.


And Ronnie will explain.

“That one there at the top has risen 12 times, the one under the alder here at the back has risen 14 times, the one by the reeds 17 and there’s one just over there, the smallest, that has risen 20 times. That last one is 2lb. So, we won’t bother with it. We want the 17-riser. That’s the big boy.”

Our guest – for these were the exact numbers on 15 May two years ago – didn’t fish a lot and by this sacred hour had caught as many fish in the one afternoon as he had the previous season. He was already happy. Even so, I was keen that he should end his day with a monster. Ronnie had watched 63 rises without wetting his line. Upstream a mayfly flitted up and down, trying to
get airborne.

“Two feet farther and Moby Dick will have him,” said Ronnie.

On cue a hole opened in the surface, a spotted shoulder whaled over the fly and the river rocked from side to side.

Catch big trout

Leave the hatch-pool back-eddies and dark corners under alder for teatime – which is why ‘Cardinal Fatty’ will break the surface.

“That’s 18,” said Ronnie. “Ready?”

Our guest, now more nervous than keen, pythoned into position. It took a few casts but none of them spooked our fish and when one hit the spot I knew it was a goner. The blimp shouldered the sky one more time, the fly vanished and our guest struck neither too late nor too soon. The giant was hooked. Ronnie was behind with the camera. I turned to give him the thumbs up but should not have cursed the moment with such hubris. The fish bolted wildly down river and ssssssssssnappp! The moment of failing elasticity stretched like elastic into a leviathan-less eternity.

“Bloody hell,” said our friend when he could finally speak. “That fish must have been 2½lb.”

“Double,” said I.

“Double?” asked he, piteously.

“Double,” agreed Ronnie. “But never mind chaps. There’s always next year.”


Now that’s what mayfly is all about.


Richard Slocock operates six beats on the Piddle and others on the Frome. All lovely and good value.
Tel 01305 848460;

Simon Cooper offers day-ticket fishing on a wide variety of beats, from Dorset to Yorkshire.
Tel 01264 781988;

William Daniel has access to fine beats in Hampshire and Wiltshire, most within 90 minutes of London.
Tel 01722 782858;

It’s not easy to find chalkstream day tickets north of London, but Mulberry-Whin is a beautiful fishery on the Test of the north, the Driffield Beck.
Tel 01377 254073;