Mayfly Time!!

Ephemera Vulgata and Ephemera Danica is often referred to as Mayflies in the UK and are the highlight for many anglers in both rivers and still waters. They are found all around Europe in lakes and rivers with good water quality and with bottom materials that consist of sand and silt. In most places where these are found it’s the best opportunity of the season to catch a trophy trout on a dry fly. Here is some facts about these beautiful insects and how to catch fish during this hatch.


Both these mayflies live in the bottom material/substrate and are burrowing nymphs that feed on organic material. The nymphs normally spend 2 years to grow before they are ready to transform into the adult stage as a winged insect. The fish they can only prey on these insects during the period of the hatch. Both Danica and Vulgata’s are very similar in size, from 18 – 25mm excluded the tails and wing wings as long as the body. The males are smaller than the females and darker. In Scandinavia we have Danicas in rivers and Vulgatas in lakes as a main “rule”. In UK you will find danicas also in lakes.

The time of hatching of insects depend on water temperature and climate.  In southern Europe and UK these flies normally start to hatch in first part of May, in Scandinavia it’s from the second half of May until July. With normal temperature in water and air they hatch during daytime like many other species mayflies, fishing can be good from around 11 to 5-6 in the afternoon. After spending a day or several days on land the insects transform into the Imago or the spent spinner and return to the water to lay their eggs. This happens on days with nice weather and not too much wind. Nice, warm, and sunny evenings is preferred. That said there are also exceptions, sometimes they come and lay eggs in daytime too when the hatch is going on. So, we must be prepared for all scenarios in terms of flies in our assortment.


Guideline staff have a long experience of fishing these hatches and our flies are well proven in battle for more than 20yrs. So, you can rest assured that the flies we sell really work. During the hatch several methods can be productive. On the lakes on windy days fishing a combo with a nymph as point fly with a dropper of a Gosling can be lethal, the Gosling looks like a hatching dun and if you add High N Dry Liquid floatant to the fly first and use the brush frequent during fishing the fly with pop up after you retrieve and looks like an emerging insect. When hatches are good trout tend to pick more what they like and quite often they go for the emerger, our Foam Mayfly emerger is a good choice for this tactics and threat only the wing case with gel floatant so that the rest of the fly is hanging deep in the surface signalizing vulnerability or an easy prey. That is what trout is looking for in this situation.

Trout picking duns is easy to spot and both our GL Vulgata and GL Danica duns are very well performing flies, these flies are made with a twisted synthetic chenille that takes up floatant, float well and hook far more fish than big foam flies. We like to fish these when they take the duns and in the first stage of the spinner fall when the fish is chasing egg laying females. The spent flies come into use when the trout is calming down and not hitting the flies so explosively, you will see it, trout taking spents can be very gentle even with big flies like these. However, when fish have seen these flies for a few days the spent can be the number one choice even if trout is chasing egglayers. Some fish just seem to wait for those spents that is much easier to catch that those flying around dipping their abdomen in the surface.


Since we try to target the bigger fish during this hatch we normally use 5wt rods for this fishing, a 4wt is also ok, but you need a rod with a little backbone to play the fish nice and fast in order to release it properly. Some people that fish in lakes prefer longer rods and if you do and want the longer reach and little more height when casting from a boat or float tube the LPX Tactical 9’9ft #4 and #5 is very good options. If you prefer a 9ft rod the LPX Tactical 9ft #5 is a super rod for this fishing, it can deal well with thinner leaders during daytime and have an action that is very well suited for a variety of tippets down to 6X.

However, during this fishing I don’t recommend you going any thinner than 5x tippet. On calm sunny days and flat water 5x is sometimes needed. As day goes into evening swap to 4x tippet and when it’s getting very low light you can also use 3x tippets on the spents. Since these flies have a bit of volume we need a good turnover for presenting the fly. The 4 Cast+ is a super allrounder that is our best compromise for both rivers and lakes with this type of fishing. Tie on a 12ft 3x power strike leader for great transfer of power and turnover, put on a tippet ring and 1,5meter of tippet of your choice.

Essential flies and gear mentioned in this article can be found here.


Remember that fishing during a heavy Danica or Vulgata hatch can be challenging, and it may take some experimentation and patience to find what works best. Try different tactics, observe the behavior of the fish and the natural insects, and adjust your approach as needed to increase your chances of success. There can be a massive influx of natural insects, making it challenging for an artificial fly to stand out. However, there are a few things a fly angler can do to make their fly more attractive to fish:

  • Some days the fish can be really picky on how the flies are riding on the surface, and often it is “the higher the better”. If you have been fishing the same fly for a while, or maybe caught a fish on it, and get refusals; change the a new, dry and impregnated fly and let the other one rest and dry on your pad.
  • Need for speed. When there are lots of mayflies hatching the fish can be really keen on some movement of the fly, just like it is disappearing away. When you have a fish closing in on the fly, give it a small twitch, and see the reaction. Other times a long, slow pull makes the fish come and grab it in full speed. Again; when giving the flies some speed, do not opt for to thin tippet as the strikes kan be pretty hard.

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