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Mayfly (Ephemeroptera).... A Short Life Story

"The lifetime of a human being is measured by decades, the lifetime of the Sun is a hundred million times longer. Compared to a star, we are like mayflies, fleeting ephemeral creatures who live out their lives in the course of a single day."

Carl Sagan

fly fishing

In spring and summer, when the sun begins to warm the water and the delicate red penstemon and tall purple lupine along the forest floor and bordering the muddy banks begin to bloom, something stirs in the fractal geometry at the bottom of the river. Waiting and foraging on plant material and detritus for up to 2 years under the stones and rubble of the riverbed, nymphs begin to emerge together toward the galaxy of the water's surface above.

Having spent so much time living under the water withstanding strong current speeds, these nymphs have flattened bodies, strong legs and gills that function as suction cups.

On their journey to the surface, the awkward looking nymphs shed their skin to expose their gossamer-like new wings, translucent and fragile. If the nymphs escape the appetite of a feeding trout as they begin twirling and swimming upward from the bottom of the river, their adult life begins as a mayfly. Breathing air now and ready for flight as a sub-imago or dun, they momentarily rest on top of the water, again at risk of being eaten by a hungry trout or additionally now, a bird.

Finally emerging at the edge of the water, the first phase of the mayfly's life, in a very brief adulthood, commences. The sub-imago mayfly discreetly crawls up onto the stream side plants and grasses rooted along the riparian borders to again rest and warm themselves in the sun. They slowly unfold and dry their delicate new wings in the blowing breezes, waiting for nightfall, before they shed once again to become the second and final adult iteration, the imago, or spinner.

mayfly life cycle

The newly adult mayflies take flight in the warm air. They dance together in the air above the water with the females flying into the center of the swarm to mate. After mating is completed, the males fly away to die on land; while the females fall back to the surface of the water to lay her eggs. She has 2-3 long slender and graceful tails, her 4 wings folded like a sailboat's sails. The tiny eggs sink to the bottom of the river where they stick to plants and rocks. After the females deposit their eggs, lying motionless on the water, as a "spent spinner" they are often eaten by trout.

An adult example of the mayfly species, dolania americana, found in the American southeast, her life is framed and completed in a matter of 5 minutes. The eggs undergo eclosion, becoming nymphs; now completing the 4 stages in the life cycle of a mayfly.

This process continues throughout the summer all around North America and worldwide.

fly fishing fly boxes

"Mayflies are the conerstone of the origin of fly fishing"

Dave Whitlock

(from Trout and Their Food)

One of the most ancient insects alive today, dated nearly 100 million years before the arrival of dinosaurs, mayflies carry a long history of contributing to planetary function.

Mayflies can be found in freshwater ecosystems distributed throughout the world,

and have shown their significance throughout more recent history in art, poetry and architecture. The imitation of mayflies to catch fish dates back to the 1st century AD.

We fish each stage of the mayfly's life cycle from nymph to adult spinner.

Nymph patterns like hares ears, jujus and prince nymphs can be fished all year.

In mid-spring to mid-summer and again in early to mid-fall, when sub-imagos like Pale Morning Duns, Comparaduns or Blue Winged Olives are present on the surface of the water, you can fish patterns like a parachute Adams, March duns and brown duns. Fish these imitations when fish are rising on the surface, either boiling or sipping gently. In northern New Mexico we have a beautiful and strong Green Drake hatch, often occurring in June.

A day or so later, after the duns have hatched and the spinners have now returned to lay her eggs, look for spent or dead females on the water's surface with her wings spread out flat, flush with the water. Trout will be rising for tricos, spent drakes and rusty spinner patterns presented with light tippett.



(adjective) lasting for a very short time.

(from the Greek word ephēmeros, meaning "lasting a day")

Although slight and seemingly insignificant to humans, other than fly anglers; mayflies are valuable nutrient cyclers that greatly benefit their aquatic ecosystems. Global freshwater biodiversity is reported to have declined by 83% since 1970. In Switzerland, for example, a recent "red list" evaluated 43% of Ephemeroptera as at least endangered. More work is needed toward assessing the conservation status of mayfly species worldwide, but the percentage of imperiled mayfly species has grown across the globe due to pollution, habitat loss, invasive species and climate change. And although as a species they pre-date dinosaurs on the planet, their individual reproductive life lasts only moments. It isn't just humans and fish that demand and deserve clean water, it's the tiniest and most vulnerable also.

I hope this helps you consider the process these insects go through next time you are on the water fishing or flipping over rocks.



Writer's Note:

I wrote this Ephemeroptera piece at the hospital bedside of my father in the Cardio Vascular ICU after he had an urgent open heart surgery. It seems ironic to me now to have been researching and writing about the brief nature of an insect's life while also fretting over the life of my own father. I wanted to add this note to encourage you all to take a moment to be thankful for all that your life holds because it is brief; as humans, living in a fast paced technology driven world, we take so much for granted every day that we just shouldn't. From our loved ones, our health, to the trees, and to the very air that we breathe...if you don't already do this regularly, take pause to inhale and fully experience and appreciate.

I would also like to add that with all the hype and publicity that artificial intelligence is gaining in the media these recent days, I still find value in the human's voice. I hesitated to post this at all from the perspective that a computer could write a better blog with no punctuation mistakes or typos and that this labor is therefore devalued. I personally reject that ai programs can communicate the written word artistically and with love. That's what I hope to give you in these simple blogs, along with authenticity and deep care for our environment. I will never give you a piece to read here that is computer generated and not from my heart.

Let me know your thoughts!

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Brandon Ruppert
Brandon Ruppert
May 30, 2023


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