Flies are common insects found across various environments, and their presence often leads to questions about what attracts them. Understanding the specific factors that draw flies helps explain their behavior. These insects seek resources that support their survival and reproduction.
Food and Breeding Attractants
Flies are drawn to substances offering sustenance for adults and suitable sites for offspring development. Decaying organic matter, such as rotting fruits, vegetables, and meat, attracts them. These materials provide liquid nutrients for adult flies and an ideal environment for egg-laying and larval development. Blow flies, for instance, are particularly drawn to meat and vegetable scraps for egg deposition.
Sugary and fermenting substances also strongly attract flies. Sweet spills, sugary drinks, and overripe or fermenting fruits are appealing due to their sugar content. Fruit flies, in particular, seek out overripe produce and fermenting liquids.
Animal waste and feces are another major draw, functioning as both a food source for adult flies and a nutrient-rich breeding ground for larvae. House flies often lay eggs in animal manure; the high protein content in dog waste, for example, makes it an ideal breeding site.
Garbage and refuse act as magnets for flies because they contain a mix of decaying organic matter and fermenting substances. Uncovered trash and food waste provide ample opportunities for feeding and reproduction.
Environmental Conditions They Seek
Beyond food, flies are influenced by environmental conditions that optimize their activity and life cycle. Warmth is a key factor, as flies thrive in warmer temperatures, preferring conditions of 75 degrees Fahrenheit and above. Elevated temperatures accelerate their metabolism and support faster breeding cycles.
Light also plays a role in attracting flies. Many fly species exhibit positive phototaxis, meaning they are drawn to light sources, particularly natural light and UV-A wavelengths. This attraction can lead them to congregate near windows or lamps, and they may use light as a navigational aid.
Humidity and moisture are important for fly survival. Flies thrive in moist conditions, as water is essential for their hydration, development, and reproduction. Damp environments, such as those found in drains or overwatered houseplants, indicate suitable breeding grounds.
The Sensory World of Flies
Flies possess developed sensory mechanisms that enable them to locate attractants. Their sense of smell, or olfaction, is developed. They detect volatile organic compounds emitted by decaying matter, fermenting substances, and animal waste from considerable distances through specialized receptors on their antennae. These antennae contain olfactory receptor neurons that bind to odor molecules, sending signals to the fly’s brain.
Vision is another important sense for flies. They have compound eyes, made up of thousands of individual visual units called ommatidia. This structure provides them with a wide field of view and is sensitive to motion, aiding in navigation and the detection of food sources or threats. While their vision may not be as sharp as human vision, it is excellent at picking up movement.
Flies also have taste receptors located on their feet and mouthparts. This allows them to “taste” surfaces they land on, determining if a substance is a suitable food source or breeding site before consuming it.