IRONTON — Besides sunshine and warm weather, some uninvited guests have greeted residents along the Ohio River as the summer months commence.

Those party crashers have been the swarms of mayflies that have annoyed homeowners and residents up and down the Ohio River.

If it is not bad enough that blood-hungry mosquitoes are out biting everything in sight, the annual influx of mayflies have attached themselves to anything they see. At times Tuesday, shaded sides of homes were covered with hundreds if not thousands of mayflies.

People who live near the river can expect to see throngs of these annoying critters that also go by similar names like “dayfly,” “shadfly,” “Green Bay Flies,” “lake fly,” “fishfly,” “snakefly,” “June bug” and “Canadian Soldiers.”

Mayflies are longer-tailed and their wings stick up like a butterfly and arrive at the beginning of summer. They are aquatic insects whose immature or nymph stage usually lasts one year under rocks or in the mud in freshwater lakes or rivers. Their adult lives are short, from a few minutes to a few days depending on the species.

Mayflies do not bite and do not transmit diseases, but can be very annoying as Shauna Miller found out while out with her niece at the Holiday Point Marina in Green Township.

“They are everywhere. I’ve had a few fly right into my hair and into my face,” Miller said, while constantly shooing away the pesky insect.

But as much as mayflies can be annoying, large amounts of them, even for a few days, signifies a good sign for summer. The more mayflies that hatch in a given year means the less polluted the river or lake is that they came from.