Fly Friday - Illustrating The Mayfly Life Cycle

    Its that time of the week again and time for a Fly Friday post.  A week or so ago I was contacted by a dedicated angler who wanted me to do a set of drawings for a tattoo he was working on.  The subject of this tatt - The life cycle of the ever important Mayfly.  My response:  Are You KIDDING - Where is my pen and paper!  Of course the image above is not actually one of his tatt. Its just my fancy way of compiling all the drawings into a blog friendly presentation.
    Never one to waste an opportunity  I thought it might be a good way to present the life cycle of an insect so important to us fly anglers.

 The Mayfly is one the worlds most interesting species of semi-aquatic insects and their population health is a great litmus test to how a streams ecosystem is doing.
  Starting life as a nymph, the mayfly can live under water for as little as a few weeks on up to a year or more depending on the species.  Some species (BWO for example) are apt to swim during this stage, while others such as the PMD or the the nymph illustrated to the right, are clingers or crawlers, and a few others - the Hex being the prime example - are burrowers.  Regardless of this, the one thing they all have in common is that during this stage they all form a hard exoskeleton that protects them from the harsh underwater environment.  What it doesn't protect them from is the hungry trout that readily feed on them.

  Once the nymph has reached the end of this first growth cycle it makes its way to the surface to shed the hard exoskeleton.  Either triggered by water temps, time of day, or any number of other conditions, the mayfly does not make this move alone.  With the right time and conditions hundreds if not millions of these tiny bugs make their move all at once. It is during this transition that the little bug is the most vulnerable to attack.  Unable to evade or hide from the predators below or above, the Mayfly is easy pickings for trout and birds with a taste for the juicy insects.  This stage of development is known to fly anglers as a dun and is a key opportunity for hooking into large amounts of trout.  Once free from the nymph form, the mayfly needs time to dry their delicate wings before they take flight to live out the rest of the sort life.

 


 As a full grown adult the Mayfly's life is a relatively short lived experience.  It is fare to say that the life blood of the Mayfly is the water system in which it has grown up and they tend to stay fairly near that source.  It is during this stage that they need to find a mate as quickly as possible before they die.  Some species such as the Hexagenia - or Hex - fly of the Midwest often does not live longer than a single night while others can linger on for a week or so.  Simple put, these flies live out their short lives like a Monty Brewster (Classic 80's movie reference there!).  They have only a short time to spend all they got or they will have nothing.

  Once they have mated the females then use their last bit of energy to complete the life cycle and drop their eggs on the waters surface.  Anytime these insects hit the water they are potential food and in this vulnerable state the mayfly is yet again in real danger.  Fly fisherman have taken advantage of the trouts love for the mayfly laying caviar by producing some highly effective patterns with flies dropping eggs.  For the mayfly however this is really their last hurrah since shortly after they drop their eggs, they will die.

    Often they will simply lack the energy to fly again.  Their wings relax and they begin to struggle in the surface tension of the water.  Of course trout never waste a good meal and they feed heavily on these flies as well.  When you look at it from the trouts point of few, the mayfly only exists to provide food for them.  At all stages they are a tasty treat for the fish and without whom our streams ecosystems would be in a sorry state.
   So for this Fly Friday take the time to appreciate the lowly mayfly who provides us with an endless supply of inspiration for fantastic fly patterns to catch trout.
                                              Have a GREAT WEEKEND!