How to Catch Trout During Hot Weather in Scottish Reservoirs

Proof That Fish Don’t Own Thermometers

Scotland has been enjoying one of those rare spells of warm weather that gets everyone talking. You know the kind. Temperatures climb into double figures for more than three consecutive days and suddenly the country behaves as if we’ve been transported to the Mediterranean.

The supermarkets sell out of barbecue food, every patch of grass becomes a sunbathing area, and social media fills up with comments ranging from“This is amazing!” to“It’s too hot, bring back the rain.”

As anglers, however, we’ve been looking at this weather slightly differently.

The recent heat has created challenges for many fisheries, with some smaller waters being forced to close due to high water temperatures and concerns for fish welfare. Thankfully, my local reservoir has continued to fish exceptionally well despite the conditions. The fish have remained active and have been feeding hard, even during bright sunshine.

If I’m being honest, I wasn’t overly optimistic when I first arrived.

Why Anglers Are Their Own Worst Enemy

Years of fishing have taught me many things, but one of the biggest lessons is that anglers are experts at convincing themselves they’re about to have a terrible day. Before the first cast is even made, we’ve already got a list of excuses prepared.

“It’s too sunny.”

“The water’s too warm.”

“The pressure’s wrong.”

“The wind’s in the wrong direction.”

“The trout are probably watching Wimbledon.”

We can find reasons for failure that would impress a defence lawyer.

Every angler knows this painful truth.

A fish showing itself is a bit like someone opening the front door, waving at you, and then immediately locking every window in the house.

You know they’re there.

Getting them to cooperate is another matter entirely.

Adapting, Experimenting, and Enjoying It Anyway

The key during these warm conditions has been adapting tactics to suit what’s happening in front of you. Summer fishing often requires a little more thought and experimentation. The days of turning up, chucking out your favourite setup and expecting instant success can sometimes be behind you.

Not that this stops us trying.

I think every angler has a favourite fly that they believe possesses magical powers. Mine certainly do. They’re usually chewed to bits, held together by hope, and have caught approximately three fish since 2022, yet somehow continue to earn a place in the fly box.

The trout, unfortunately, often have other ideas.

That’s part of the challenge and part of the fun.

Fishing has always been one giant puzzle. Every trip starts with a new set of clues and it’s our job to work out exactly what the fish are doing.

Sometimes you solve the puzzle quickly and look like a genius.

Other times you spend six hours changing flies, changing lines, moving locations, and questioning every life choice you’ve ever made.

On one recent trip I was absolutely convinced I had cracked the code. I’d found the right depth, the right retrieve, and the fish were responding beautifully.

Naturally, within thirty minutes they completely changed their minds.

Trout have a remarkable ability to keep anglers humble.

Just when you start imagining yourself on the cover of a fishing magazine, they remind you that you’re essentially standing in water waving feathers around while trying to outsmart a creature with a brain the size of a pea.

And somehow, the fish wins.

Despite that, the reservoir has continued to provide some fantastic sport during this warm spell. Once the right tactic has been found, the rewards have been more than worthwhile. The fish have been willing to feed and have proven that bright sunshine doesn’t always spell disaster.

I think that’s one of the biggest takeaways from the past few weeks.

Far too many anglers write off a day’s fishing before they even leave the house. We look at the forecast, see sunshine, and immediately decide it’s going to be impossible.

The fish, meanwhile, are carrying on with life as normal.

They’re not reading fishing forums.

They’re not scrolling through weather apps.

They’re certainly not checking Facebook to see whether Dave from down the road thinks the conditions are poor.

They’re just being fish.

Another thing the recent weather has reminded me of is how important it is to simply enjoy being outdoors.

Yes, catching fish is brilliant.

We all love seeing the rod bend over and feeling that unmistakable pull on the end of the line. It’s what keeps us going back.

But there’s something special about being beside the water regardless of the catch rate.

The fresh air.

The wildlife.

The peace and quiet.

Well, peace and quiet until a swan decides you’re too close to its personal space.

Or until another angler appears and immediately asks the question every fisherman secretly dreads:

“Any luck?”

Because no matter what answer you give, it never feels right.

Catch loads and you sound like you’re showing off.

Catch none and suddenly you’ve become the local expert on why fish refuse to eat.

For me, though, that’s all part of the experience.

There are worse ways to spend a day.

You could be sitting in traffic.

You could be cutting the grass.

You could be helping someone move house.

In comparison, sitting on a boat in a reservoir with a fly rod in your hand seems like a sensible life choice.

At least that’s what I keep telling myself every time I buy more fishing gear.

Like most anglers, I already own enough equipment to open a small tackle shop, yet somehow, I still manage to convince myself that one more fly line, one more rod, or one more box of flies is absolutely essential.

My wife remains unconvinced.

As this warm spell continues, it’s important that anglers remain mindful of fish welfare and support fisheries making sensible decisions when conditions become challenging. But where waters remain healthy and open, there is still some excellent fishing to be had.

The recent sessions at my local reservoir have certainly proved that.

Despite the sunshine, despite the warm conditions, and despite all the doom and gloom that tends to accompany summer fishing discussions, the trout have continued to feed hard and provide some fantastic sport.

So don’t be too quick to write off your next trip.

Get out there.

Experiment a little.

Adapt your tactics.

Enjoy the surroundings.

And remember, the fish don’t know what the weather forecast says.

Because if the last few weeks have proven anything, it’s that while Scotland has been experiencing a heatwave, the fishing has been just as hot.

Tight lines, and if anyone asks how many fish you caught, remember the first rule of angling: the number automatically increases by at least 20% when telling the story later.

Fly-Fishing Report: Threipmuir Reservoir, 21 July 2026

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