Simply so, how long does a fish fly live?
seven days
Furthermore, why do mayflies only live for 24 hours? As Poinar explains, mayflies don't really have the option of living a long life: "After their mating flight mayflies are usually dead by the end of the day. There's only one thing they really care about on that one eventful day, and it's not eating. They don't even have functional mouth parts."
Also question is, what do Mayflies do?
Mayflies are a vital link in the food web of freshwater ecosystems, making energy stored in algae and other aquatic plants available to higher consumers (other invertebrates, fish, birds, etc.).
Why do mayflies die so quickly?
Adult (winged) mayflies have no functional mouthparts and cannot eat. Mayflies have evolved to spend a year in the nymph form, taking on nutrients and growing, and then to pass on their genetics to a new generation in a very short period of time.
