Dead Flies

     You can drown a fly and bring it back to life as shown in THIS YouTube video. Actually, a fly breathes thru tubes in the sides its body and like most bugs can exist for long periods with little oxygen. The fly goes into a homeostatic state in which it is conserving what little oxygen it had before drowning. The salt removes the water from its breathing tubes by a process of diffusion, or leaching. With the water gone from the tubes, the fly can start breathing again and slowly returns to normal. 
     Tricks aside, in the winter and early spring have you ever found a cluster dead flies littering your floors and window sills? If you live in a rural area, it’s common to see them this time of year. These are cluster flies, which can be found throughout the United States except in the states bordering the Gulf of Mexico as well as Canada and Europe. 
     Cluster flies are known for the way they tend to hibernate or “cluster” in wall voids or attics during the colder months. They can number anywhere from a few dozen to in the thousands. 
     They are a nuisance because they die all over peoples’ homes in the spring, but it’s the fall when the problem actually begins. All those dead flies have actually been living in the house all winter long, and now they’re trying to get out. 
     Cluster flies are not like the usual houseflies you see buzzing around rotting food and animal excrement. They feed on flower nectar and like to sunbathe outdoors. Because of this there is no worry about them laying eggs in your food or making you sick. 
     They’re more common near vast stretches of fields because cluster fly larvae are parasitic to earthworms! You will never see cluster fly larvae in trash cans because the adults lay their eggs in earthworm burrows! The larvae then infest and feed on the worms, and when they pupate into adults, they emerge from the ground. 
     Unfortunately, in addition to lady bugs, ants, stink bugs and hornets, cluster flies love the warmth of houses...they are attracted to warmth. On sunny days, you may see them on the southern side of your house soaking up some rays.
     When it cools down in the fall cluster flies squeeze through tiny holes in your eaves and siding and around your chimney and pipes in a home invasion. Once inside, they hibernate. They cluster together (hence the name) in corners of attics or in wall voids to stay warm. 
     On warm days in the winter and spring, they wake up and try to get out. But instead of going outside, because sometimes it’s still very cold, they buzz around until they drop dead, usually on window seals and floors. 
     There is no sure way to keep cluster flies out on your house. Trying to up every little hole will turn out to be a hopeless project The best way to prevent a cluster fly mess in the spring, is to have the outside of your house treated in the fall (around mid-September to mid-October.), but who’s going to bother with that? The best best is to just suck up the dead flies with a vacuum cleaner.