What To Do If There's A Sudden Swarm Of Mayflies In Your Yard

Imagine this: you step outside on a calm spring evening to wind down from the day when, all of a sudden, you're surrounded by mayflies. They are everywhere, flying around your yard and making it hard to enjoy your time outdoors. These ancient insects have been around for around 300 million years, and while they are harmless, they're also incredibly annoying. What can you do about them? Well, start by turning off the lights and closing up your home. Mayflies, like many other bugs, are drawn to light.

Some insects evolved this behavior, called positive phototaxis, for navigation, orientation, and survival using natural light sources. Artificial lights, however, interrupt this process. In fact, a single porch or yard light can attract thousands of winged critters. When mayfly populations emerge from water bodies in late spring to early fall, they fly toward the first source of light they see.

Light coming from inside your home can also draw mayflies in. Even closed but uncovered doors and windows will attract these pesky flying bugs. The minute you spot a swarm of mayflies, you need to turn off all the lights inside and outside your home. However, that might not be practical. If, for some reason, you can't turn off your lights, at least close and cover every door and window or add screens. As an aside, don't get rid of lizards in your garage and around your home. They eat mayflies! If, after turning off the lights, you still see a few stray mayflies, the lizards should take care of them.

Not all lights attract mayflies equally. Insects, including mayflies, respond most strongly to short-wavelength ultraviolet and blue-spectrum light. LEDs, for example, typically release this kind of light. If you've switched over to LED bulbs to reduce energy usage, as most homeowners have by now, the downside is that they attract mayflies. Switching to a warm-spectrum LED can help. Similarly, a sodium vapor light bulb for outdoor lighting will keep more bugs away than most other options. They also emit a warm-toned glow that doesn't seem to attract mayflies as much.

If you can't avoid using bright blue LED bulbs, try changing their placement. Set the light on a tall pole well outside of your outdoor seating area or spots you frequent in your yard at night. If the light source is indoors, close the curtains or hang shades in the windows. Either option should stop your patio or porch from becoming a mayfly magnet. Installing motion sensor lights can save you energy and limit the mayfly beacon effect of other light sources.

Lights aren't the only thing that attracts mayflies. Standing water also plays a big role. Mayflies lay their eggs in water. In fact, it's where they spend most of their lives. Their larval forms can live for up to three years underwater. Make sure you get rid of any standing water in your yard, or cover it from spring through fall when mayfly eggs hatch. Another all-natural way to repel mayflies, according to our pest control expert, is avoiding insecticides to encourage predators.