After New Mexico's expanded drought, all that lovely rain means swarms of flies are everywhere. You can make a good fly trap using some plastic water bottles, apple cider vinegar and sugar. Cut the tops off the bottles, and invert the top part into the lower section—forming a funnel—and tape them together. Pour about 2 inches of apple cider vinegar in the bottle and add ¼ teaspoon of sugar. This trap will attract and catch many different kinds of flies, no matter their normal food preference. If you have a large building or yard, you can use gallon milk jugs cut the same way with about three times the vinegar and sugar.
The most common fly is the house fly (Musca domestica). House flies have a gray thorax—the part where its head connects and wings attach—with four dark stripes and a mottled abdomen or posterior portion. These flies are considered “filth flies” and will feed on excrement, garbage, carcasses and even human secretions from wounds and mucous membranes. If you accidentally eat the larvae, aka maggots, in contaminated food, they can survive in your intestine. House flies can harbor over 100 different pathogenic organisms and are capable of transmitting more than 65 diseases, as well as bacteria that can cause duodenal and stomach ulcers. From a global perspective, it is the most common fly found around homes and areas with livestock.
When attempting to swat a fly, remember it has an unblurred range of vision of only about 1 ½ feet. So you should aim your fly swatter approximately 1 ½ feet behind the fly. When it takes off from a horizontal surface, it jumps upward and backward. Simply set out a saucer filled with bubble soap to attract and kill house flies. Adults eat only sugar, so make traps using some light Karo Syrup, honey or sugar water with 5 percent boric acid. I have frequently written about repelling flies by hanging Ziploc bags filled with water around doors and windows. When the sun is shining, the bags' refractive sunlight seems to disorient flies, and they won't come in the building. Based on mail I've received, these bags work very well.
Another common fly is the little house fly (Fannia canicularis). The little house fly is dull gray with yellow on its upper abdomen and three dark, longitudinal stripes at the top of the thorax. These flies resemble house flies but revolve in circles in the middle of a room or porch and never appear to land. It can lay eggs in any organic material, including compost piles, pet feces and dead leaves. It has even been known to enter the urinary tract of naked, sleeping humans, causing urinary myiasis, a parasitic infection. To prevent these flies from appearing in the first place, empty and clean all food-handling equipment, dishes and garbage containers daily, and remove and bury all animal droppings, fruit and organic debris inside and outside your home. Little house flies do like beer, so stir two packets of aspartame and two inches of beer in an open container to trap these flies. Use a fly swatter with a sticky side to swat them when they circle.
The blow fly (Calliphoridae: Phormia, Phaenicia, Cynomya and Calliphora) is also very common here. It is larger than a house fly, and it's normally shiny green, blue, bronze or black in color. Blow flies subsist on decaying animal matter; if you have them in your house, it's a strong indication of a dead animal in the wall or ceiling. Early in an infestation, sometimes the only sign of these flies is when their larvae fall from a ceiling void onto the floor. Find and remove the animal carcass they're feeding on, and it will speed up their departure. If you can't locate the carcass, there isn't much else you can do but be patient and wait for the animal remains to dry out. Blow flies also lay their eggs in dog feces or any organic matter with a high protein content, including dry cat food. Entomological trivia: Blow flies are used by forensic entomologists to establish time of death in human fatalities.
Other species of flies will also be attracted into these vinegar traps, but these are the most relevant to New Mexico residents. Remember that pesticides are never necessary for fly control or practically any other household pest. If you want to, you can control all pest infestations in your home or business yourself. Now if you have termites, you should enlist the services of a qualified pest management professional.