79 - Top Tips: Fishing the Mayfly Hatch

FISHING THE MAYFLY HATCH – TOP TIPS AND FLY PATTERNS

Arguably the finest time of all to be a river fly fisher, late May and early June offer exceptional sport. And this season, Turrall have a host of new mayfly patterns to get the best of the hatch where you live. 

Is there any better time to be alive than late May and early June? You can keep Christmas for all I care- THIS is the most wonderful time of the year!

Through my own fault, I had missed the main mayfly hatch in 2024, hence this time felt even more keenly anticipated. With new beats to try on the excellent FishPass scheme (https://fishpassapp.co.uk)to explore, as well as new waters to try with my new club.

Mayfly ID and life stages

The really exciting part of the annual mayfly hatch is how easy it is to copy the insects, and do so with large artificial flies, typically a size 10. They’re easy to identify too, much bigger than the wider mayfly or “olive” family. Females are often an inch long (24mm), males slightly smaller, and are typically pale yellowish cream colour.

For those less experienced I feel duty bound to explain that what we are dealing with here, Ephemera Vulgata, is really just one of many “mayflies”. It’s just that anglers tend to only call this big, juicy, iconic insect the “mayfly”. The rest, we tend to refer to as “olives”. 

Of course, these unmistakable adults are what captivate the attention of trout and anglers alike- but the larva (or “nymphs”) have already lived for up to two years. Unlilke smaller “olives” that live among rocks and stones, our vulgata mayfly larvae prefer mud and sand. Hence, they often do very well on rivers that aren’t the prettiest or suffer from siltation! On this basis, do ask around and don’t always assume you need access to expensive fishing to get a bumper hatch!

The next obvious question is why are we so keyed in on dry fly fishing when the adult mayfly only lives for around a day? Well, it’s true that trout undoubtedly eat the odd mayfly larvae and there are plenty of artificial copies. However, for most of the time these are not available to trout- hence the main focus for fly fishing is as the adults hatch, breed and die.

Part of this also has to do with the evolutionary stategy of these insects, which is to hatch en masse, driving trout wild! It might look like carnage to us, but this ensures that through sheer weight of numbers, enough mayflies manage to reproduce and start the whole cycle again.  

New mayfly patterns – and matching to life stages

The easiest way to approach the mayfly hatch is by breaking the life of the adult insect down to three stages. In simple terms we have birth, life and death: or to use common angling terms, three definite phases: “emergers” that are just hatching, adult “duns”, and finally dying or “spent” mayflies, also known as “spinners”.

While an adult mayfly only lives for a day, there are quite often big variations day to day. At first, the flies only hatch in dribs and drabs. The trout won’t go crazy for them right away- and we might have to fish cute in these early stages.

Turrall’s new “Say Ahh” emerger Mayfly. Subtly inviting and perfect for early in the hatch.

We then have the main hatch, when fish go bananas! Mayfly are everywhere and the trout now have a taste for them.

(above) The Detached White Drake- lively and buoyant to simulate an adult “dun” that’s just hatched or is struggling on take off.

Lastly, we have the latter stages of the hatch, when trout are likely to be keyed into dead insects, splayed on the surface, having done their final act. 

The Spent CDC Mayfly – a hapless, sitting duck.

First blood on the Tale

Predicting hatches is seldom straightforward- but this year, with a very sunny May, action kicked off unexpectedly early. This was brilliant news for a guided day on the River Tale. A tributary of the Otter, set in gorgeous estate grounds at Escot House, this river is open to anyone on the FishPass system.

My guest, Steve Boon, could hardly have picked a more appetising day to return to fishing after a long absence. After a casting lesson, we saw the first mayfly or three lift off the water by late morning. As we ate lunch, they just kept coming, and by this time the trout started to identify them, too. Time to step up our leaders and scale up our flies.

At this stage, with active fish but still early in the hatch, an emerger made perfect sense. One of Turrall’s new Say Ahh emerging mayflies got the nod (above). With rising fish, the anticipation was keen- and we saw one small trout have not one but three attacks on a single hapless, hatching fly, before devouring it!

The main challenge was the spookiness of fish in this cute little river- and a really badly placed fencing wire across what looked like our hotspot. Nevertheless, Steve flicked out the fly bang on target using a catapult cast and it was taken emphatically! What a great way to get reacquainted with fly fishing after a long layoff.

There were a string of other rises and near misses, too, including cracking half pounder that thrashed the hook clear! And this was just the beginning.

Hatch time on the River Culm

Encouraged by earlier than usual signs of life, I set out on the River Culm just two days later- and was not disappointed. One lesson with mayfly is not to rush. The hatches very often don’t go crazy until the afternoon, and get better and better as the day goes on. All the wiser, therefore, to watch the show at leisure and tackle up with care.

On this basis, I got my to do list killed in the morning and took a leisurely walk on the river just after lunch. Already, hatching adults were a regular occurrence- and compared to the earlier session, takes were more full-blooded.

There is no need for feather-light tackle once mayflies are prolific. A 4 or 5 weight outfit, and leaders and tippets no lighter than 5lbs are the order of the day. Don’t worry about going a bit thicker with line, because typical mayflies are so much heavier than your usual river fare.

While I started the session on an emerger, I quickly changed to an adult pattern once the rises got rougher, and some of the best action came not fishing “dead drift” but by waking a fly that had been well dried and treated well with floatant. This is as exciting as it gets, with some really violent takes! 

Exploring the Culm, you can see why it gets such a good mayfly hatch; the banks are a mixture of mud and sand, perfect substrate for mayfly nymphs. And while sadly not all insects are thriving, some of the best mayfly hatches I’ve seen in Devon have come on this river. My older brother, Ben Garnett, takes the biscuit here, however, with a best day of over forty fish in a crazy May session!

Spent spinners and last casts

If you are the sort of angler who takes ten “last” casts, mayfly season is most definitely your time. Too many anglers leave the water early, when the best action of all can be late afternoon and into evening. This is especially true when we find the “spent” flies that are dying on the water after breeding.

These hapless creatures tend to be females, which drop their eggs and then give up the ghost, giving trout the easiest meal they will ever have. Tellingly, on my Culm trip, one of the last fish I had not only gave the slowest and most emphatic rise, but looked like it was well and truly stuffed! 

A very full trout!

With late hatch fly choices, I really like a pattern with the capital “T” shape of wings at right angles- and a CDC Spent Mayfly really looks the part.

That said, you can occasionally bend the rules, especially if the fish are not cooperating. Sometimes, it is as if they have so much choice, or have eaten so many morsels, you have to give them a little more reason to eat your artificial. And on this note, it’s worth having a curveball or two in your fly box. Darker and livelier flies stand out where “matching the hatch” isn’t the right option any longer.

The Stimulator Mayfly- for when the fish need waking up again.

The best fish of my session came late and had been rising under a sandy overhang, where the water was eddying back on itself. The fly only needed to settle for two seconds, and it was slurped down without a second thought. Simplicity itself for a beautiful, foot long wildie!

Further thoughts…  

As I type this blog post out post haste, there is still ample time to get onto the mayfly hatch! While the thick of it is right now, there will still be juicy flies spotted well into June- and it’s also worth keeping an eye on other fisheries. On several occasions, I’ve seen large carp and coarse fish taking them on spring-fed lakes, for example.

I had an absolute ball field-testing the new range of patterns, but it’s also fun to get to the vice and tie your own, of course. This is one time of the season when you can really go for it, with big, emphatic patterns! Whether you like to go suggestive or ultra realistic, the possibilities are endless- but it always makes sense to follow that life cycle and have a mix of emergers, duns and spinners in your box.

Here’s to a thrilling finale to the mayfly season- savour it while you can!