Mayfly adults live brief and perilous lives.
Mayflies emerge from the water as short-lived adults with one objective: to mate.
The mayfly is immediately beset by other creatures that would feast upon it. Fish frequently jump from the water to consume it. The fish in this picture is the shadowy presence that has missed the mayfly (and its reflection) just above the surface of the water.
Birds pick emerging mayflies from the air. This is a Chipping Sparrow.
And this is a Yellow-rumped Warbler.
Yet some of the mayflies do survive to mate before they die. Here the female is on the top and below, inseminating her, is the male.