We’re four in a boat – five if you include Coral, the German wire-haired at the prow, sniffing the breeze – sculling along the shoreline of Loch Affric, picking a mazy route over headlands, into bays and close in against fallen trees or ancient fence-lines. The day has cleared and stilled to open a parallel universe beneath us. The sky, a child’s version of itself – too blue, clouds just too white and fluffy – meets its tea-stained hyper-reality at the loch’s vanishing point and a heavy heat presses down, sandwiching us between. Iona trails a finger through the mirror surface. Vicky is all but asleep at Coral’s feet. As the poet Louis said, “We ain’t got no ambition.” In fact we’ve composed a gone fishin’ ditty of our own, a little mantra we’re using now and again to charm the fishes of Loch Affric.

It ain’t Gershwin. It doesn’t even scan that well. But it works. Pretty much every time we hit the final couplet one or other of the rods trailing flies out back jangles into life. Or that is how it seems. It’s hard to tell cause and effect apart when the loch is so full of hungry fish. They kiss the surface, and tell messages from that other dimension, all over the place. This is perfect fishing for kids. The cast is all but done for them, so long as I keep rowing. And for some reason I’ve never understood – I mean when does a hatching midge pupa skim along the surface like a toy boat? – it’s lethal.

But the ditty contains a hint of dishonesty and the fish that it’s lying to are the ones that seem reluctant to bite. If we did catch the biggest fish we’d put it back. And all the little dinks, of which we’ve had a half-dozen, we’re putting them back. But the pan fish, they’re staying aboard – or at least enough of them to make a sensible lunch.

That’s the thing about a healthy loch with decent spawning burns – you can guiltlessly rap a few trout on the head, cook them when they’re so fresh they curl up like the paper from a fortune cookie and remember the time before it all got complicated, when fishing was fun because you got to eat your catch. Last year I sowed what may prove to be the seeds of a passion for fishing in my children by cooking a sea-trout on a fire made from driftwood on rocks by the shore. They scoffed the smoke-wreathed flesh of the fish about 10 minutes after I caught it and voted it the best thing they’d ever tasted – except for chocolate. Now they want more. I row on.

Pinned to the wall above my desk is the Suirbhéireacht Ordanáis No 20 Dingle Bay map I bought as a teenager on one of my summer hols in Co Kerry. It’s there to remind me of the place where I learnt all of this myself: a necklace of loughs that curl back into the mountains above Lough Currane – the foothills, I suppose, of Mcgillycuddy’s Reeks.

There are several of these lough chains all within the same catchment. The first one I ever explored I would have fished with a worm and a spinner. Simon and I were dropped by his dad at the top of Cahernageeha mountain above Caherdaniel. We crossed a peat bog and a 1,500ft ridge before climbing down a 700ft drop to Coomrooanig Lough and the nameless puddle above it. We probably had a Mars Bar, a cheese sandwich and an apple. We drank from the lough. If the weather closed in we had instructions to go out the far end, downhill towards Lough Currane. Otherwise we’d come back over the top and walk back to the telephone box in Caherdaniel.

ABOVE TOOREENBOG LOUGH
In fact, we’d have been happy up there for a week. The lough was full of trout and we caught tons of them. Only the biggest were pan-sized, but we kept at least a half-dozen of those and took them home for supper. I think I did a sketch of them laid out on a plate. They were pale, sandy fish and they tasted just fab, especially with Irish soda bread and scrambled eggs.

The following summer we found the chain on the northern side of Currane above Lough Derriana, the one from this map. Derriana is a big lough and Currane’s sea-trout ran into it. But they couldn’t get up the near-vertical drop of the stream that drained Tooreenbog Lough. So the fishing there was free to anyone who asked the farmer nicely. We had the impression that we were the only ones. We saw no footprints other than our own and mountain goats’. We’d turn our back on Derriana and follow a little stream into the valley above. Flat ground at first, a peat bog crossed by fences giving way to a moraine of mossy, hollow land strewn with boulders, the stream coming and going, above ground, below it, the lough for ever over the next brow – until finally we reached it.

THREE FLIES, THREE FISH TO THE CAST
Tooreenbog was, in most lights, an almost melancholic body of water but at its head was a waterfall that seemed to invite an exploration of what lay beyond. The valley curled away, its end beyond sight, but with some sort of siren call about the place. We heard it and followed and found over each ridge a new lough, each smaller than the last, each pocked with rising trout and dripping with silence, until we reached the end, a sheer wall of rock 500ft high, split by a waterfall dropping off the plateau above to vaporise against fern-covered rocks below. The final lough was pressed up hard against this slope and its windless surface reflected the place like glass.

The valley was magical. Even boys hell bent on eating every trout that swam could appreciate that. We always came back with a dozen pan fish. In a year of trying I doubt we’d have dented the stocks. It is a cliché of rose-tinted memory, but it was true: with a team of three flies you could bet on three fish to the cast below the waterfall in Tooreenbog.

Things aren’t quite as busy on Affric. The day has ground to a halt against buffers of still air. Only the occasional pulse of breeze lifts the noise of a waterfall from up on the hill to lay it down again across the surface of the loch and vanish. That and the rhythmic glopping of the oars are the only sounds. Even the little fish have gone. Our promised scorched-trout picnic might consist of sandwiches and crisps. I crank up the outboard for a 20-minute blast to the western end where a bigger stream comes in off the southern shore, filtering whatever nutrients are up there on the hill into a reedy bay. I slide the boat in against the shoreline, tether its rope under a boulder and – grabbing the nearest fly rod – head straight to the mouth of the burn. Here the dark water stirs into lines of foam and bubbles, pushing a current 10yd out into the bay, that falters and curls back slowly. A good trout hits the top dropper right up against the rocks by the burn, another where the current gives out. Now we have two fish for lunch, neither caught by the kids. It’s time for the big guns.

In the tackle shop on the way up I gave them the choice of a few flies and a spinner each. Patrick took my advice and went for the black Mepps with red spots. Iona didn’t and got a bright silver thing with red calf’s tail trailing out the back. We moved on to the beach, teaming up with Rod, Alison, a littler Patrick and Oliver – who had been fishing the northern shore with no more luck than us on the pan fish front.

It could have been the weather – a moodier drift of clouds and wind stirred over us and lifted the oppressive blanket – but that alone would have accounted for a more even distribution of the catch. Only Iona’s rod, with its Liberace spinner, bent over again and again, each time to the best part of a pound of trout, until four lay on the sand behind her, like some small fraction of a Galilean miracle dropped down beside a loch in Scotland. We had our lunch and the sacred spinner of Affric became legend.

Gone Fishin’, the Rangeley-Wilson version

O biggest trout in Loch Affric,
To not catch you would make us sick.
To dance a while would be just fine,
So come and jangle on the line.

Now is not the time to fast.
Take a look at our next cast.
Grab the fly and hold it tight,
And we will have a nice play-fight.

We promise that we will not eat you,
We’ll be happy just to meet you,
And let you go then after all,
And hang your picture on the wall.

LOUGH TROUT: HOW AND WHERE TO CATCH (AND COOK)

TO CATCH A LOUGH TROUT
You need a 9ft six-weight rod, a floating line and leader with three flies. You cannot go wrong with a Bloody Butcher on the point, a March Brown or Invicta on the middle dropper and a Bibio on the top dropper.
Spinning for kids: a 7ft or 8ft rod that casts 1⁄4oz to 1⁄2oz; Abu Droppen or Mepps spinners of the same weight; 6lb mono.
Best places: where streams come in, shallow reefs or bays. Look for wind lanes (trout feed upwind of them) or work the shore the waves are hitting
or the lea shore where the ripples start.

TO KEEP A LOUGH TROUT
Clip the barbs and return the small fish and the large fish. Set yourself a “slot limit” of 8in to 14in (depending on the loch) and don’t kill more than you can eat for a fresh shore-lunch or supper. Freezing them is a crime.

TO COOK A LOUGH TROUT
A driftwood fire, set in a ring of stones, burnt hard, so the embers are glowing hot. Suspend the trout over the heat on the wire frame nicked from a grill pan. A bit of heather on the fire does wonders for flavour. Don’t overcook it.

WHERE TO GO
The best guides are The Trout Lochs of Scotland – A Fisherman’s Guide by Bruce Sandison and The Trout and Salmon Loughs of Ireland by Peter O’Reilly. Both are published by Unwin Hyman.

SIX LODGES WITH LOCHS
Morsgail Lodge
Rhidorroch
Dell House
Inverinain Lodge
Heights of Kinlochewe
Lairg Lodge