Do mayflys "dry their wings"?

[Maurice]

I hear this quite often, especially in the BWO's threads regarding their sluggish take offs.

I was told 25 years ago by my mentor that if a mayflys wings get wet they will never dry and the fly will become a drown/cripple.

I do acknowledge and purport that when the mayfly emerges from the shuck in the meniscus (surface film) it will often, depending on species, take a few moments to pump their wings up with blood/fluid before beginning flight.

So perhaps this is the activity the mayflys are involved in when struggling to become airborne.

Whats your opinion?

 

[littlelehigh]

My opinion is they have just transformed and haven't quite figured out what the hell these big things are for sticking off there back. It takes them a few second to learn to work them. Some bugs put them flat and don't lift them back up and get stuck in the film and others motor em like crazy and in a George Carlin voice say "Wooooooo nifty ish man" an proceed to take off.

I've given up on trying to justify every aspect of fly fishing and the bugs trout eat. Can you tell? Just stating the conclusion I have come to.

 

[TimMurphy]

Dear Maurice,

"Drying" their wings is perhaps a poor choice of words but I don't think most of them can fly right out of the box?

By the same token I'm not ready to believe that every mayfly that accidently gets a drop of water on them while hatching is doomed to a quick and sudden death.

They usually take some time to actually get up into the air. On damp, dreary days that time seems to be correspondingly longer in duration, which is good thing because most fish are hardly athletic or accurate enough to jump 12 inches into the air to catch a flying bug.

Regards,

Tim Murphy

 

[dryflyguy]

I checked #3

I do know that they definiitely struggle more on cold, windy, or rainy days

 

[turkey]

Epeorus plueralis emerge from their schucks while still under water and swim to the surface as a dun. Hence the popularity of the Quill Gordon wet fly. Their wings would definitely be wet.

 

[rrt]

I'm not really sure, even after allllllllll these years. I have seen sulphurs float long distances in cool weather before flying off, but I have also seen them virtually explode into the air without drifting at all once they hit the surface on really warm May/June evenings.

 

[DaveKile]

I am with Dryflyguy. I think weather has a lot to do with how they take fight as one of the factors, but species and time of year are also equally as important.

Today when BWO's were emerging out of the 50 degree water they hit the 40 degree air. I think some then slowed up and struggled a little with the cooler air. They would fly up and then fall back down on the water.

I think many species would act in a similar many with cooler air.

 

[tomgamber]

I use to care about all those details. I really don't care any more. I'm not even sure I care to match the hatch perfectly as a tactic. After decades of thinking in a matching manner and having success, I just look at it as a hint and wonder if I can;t catch those stupid fish on this rather than that in spite of what I see. Kind of challenging nature. I've caugth trout on and Adams in a sulfur hatch and on sulfurs in a drake hatch and such things. Its all still interesting listening to the debate. But I see just enough differing opinions about things that are supposed to be back and white to have abandoned any classic "this is how it is" approach.

 

[pcray1231]

turkey is correct. There are some species (quill gordons included) which escape their nymphal shucks on the bottom, and "fly" to the surface with wings intact. Some do the same near shore, and then crawl up something, like a rock or vegetation. Some crawl ON shore before emerging. And yet others do the classic, where the nymph swims to the surface film, and then the fly emerges on the film.

These myriad of different hatching behaviors is one reason it pays to learn the hatches, and not be satisfied with simply observing "size and color".

To answer the question, I'm not really sure. Many species absolutely float a ways. They don't have to be "struggling" per se, sometimes they just float in the classic wings up pose, like sailboat. I'm confident that it's because they CAN'T yet fly. Whether it's wet wings, or if it just that they need time for the wings to harden I'm not sure.

 

[caveman]

The little BWo's I saw hatching today on the Donegal were just floating like Pcray mentioned. Little sailboats. They were stacking up in the backwater eddies, I was kind of amazed that there was not more feeding activity.

 

[afishinado]

I've read about the "drying their wings" myth in entomology books several times. Here's a good summary from the Troutnut site:

Mayfly nymphs emerge into duns in several different ways. Most often, the nymph swims to the water's surface and splits open its exoskeleton above the thorax. The dun wriggles out onto the surface, where its wings fill with fluid hydraulically and allow it to take flight. (In contrast to the common myth of mayflies needing time to "dry their wings," this process is more like inflating a raft.) Different species may be quick or slow at each stage of this process. Some take a long time to escape their nymphal shuck, making flies that imitate these "emergers" especially effective. Some species very quickly take flight when they hit the surface, while others ride the surface for some minutes like little sailboats, a prime target for hungry trout and a welcome sight for the dry fly angler. Cool or windy weather may prolong these struggles and increase the availability of mayflies to trout.

Many important species follow completely different emergence patterns. In some, full winged duns emerge on the bottom of the stream and float to the surface. Others swim to shore and crawl out on land before emerging. Learning to identify mayflies and associate them with the right behaviors gives an angler an advantage: the ability to make a good guess about which style and stage of emergence to imitate, simply from seeing and recognizing some duns or mature nymphs.

Link to source: http://www.troutnut.com/hatch/4/Insect-Ephemeroptera-Mayflies

Further, at times the process of filling their wings hydraulically is slowed by cooler air temps, keeping the duns on the surface for a longer time. This is especially true with BWOs since they hatch during the colder seasons.

 

[Chaz]

Well in cool damp weather I see a lot of mayflies struggle to get airborn, they may jump up from the water or they may just drift for a long period then take flight. Either way I like it when it happens, it doesn't always mean I'll catch fish. but it usually does if I'm imitating the correct bug.
For instance one day on Toms Creek, I was witness to Quill Gordons struggling on the surface, QG hatch on the bottom and swim to the suface, it was early Arpil, cloudy and chilly, and every bug was drifting long distances until they took flight if they did at all. I say this because there were probably as many flies lying crippled on the surface as there were taking flight. On warm days QG's just burst from the surface.
I've also seen this activity in the evenings whent he air is cooling down, flies drift long distances before getting airborn.

 

[MKern]

I think they are filling them with fluid for the first time, like a butterfly.

If they are drying them, how do you explain th emayflies that hatch on the stream bed and swim to the surface as adults?