Horse flies, with their striking iridescent bodies and vibrant eyes, might catch your attention, but their bite is far from fascinating. These persistent pests thrive in humid outdoor settings, especially near bodies of still water, making life miserable for humans and animals alike. Understanding how to manage horse fly populations around your home, particularly near pools and gardens, is crucial. This guide will delve into effective strategies to keep these biting flies at bay and explore the nature of their bites.
Understanding Horse Flies: Biology and Behavior
Horse flies, also known as gad flies, belong to a family of flies notorious for inhabiting marshy and damp environments. Their metallic sheen can make them resemble other fly species, but some horse flies are distinguished by their brilliant green eyes.
Typically, horse flies measure between ¾ to 1 inch, placing them in the size range of a house fly, although some species can be as large as bumblebees. They are characterized as robust and swift fliers.
The lifespan of a horse fly ranges from 30 to 60 days, encompassing their transformation from egg to larva, pupa, and finally, adult. Females deposit egg clusters on vegetation, and these eggs overwinter as larvae, hatching in the spring and maturing into adults by June. Adult horse flies favor cool, moist habitats like streams, swamps, and woodlands.
Why Horse Flies Bite: The Female Factor
It’s the female horse flies that are responsible for the painful bites. They bite to extract blood, consuming up to 3 ounces in a single feeding. Similar to mosquitoes, this blood meal is essential for egg production. Equipped with blade-like mouthparts, they lacerate the skin and then lap up the blood. To maximize blood intake, they inject an anti-clotting agent at the bite site, ensuring a continuous flow.
In contrast, male horse flies are non-biting. Their diet consists of nectar, honeydew, and plant sap.
Horse Fly Bites vs. Mosquito Bites: Key Differences
The fundamental difference between horse flies and mosquitoes lies in their blood-feeding mechanism. Mosquitoes use a needle-like proboscis to pierce the skin almost painlessly, while horse flies slice and sponge, resulting in a significantly more noticeable and painful bite. This difference in approach is why horse fly bites are often considered more painful than mosquito bites.
Furthermore, horse flies can transmit diseases, including swamp fever, or equine infectious anemia, which can cause serious health issues in horses, such as fever, weight loss, and anemia.
What Attracts Horse Flies to Your Property?
Horse flies are drawn to sunny, warm, and humid conditions. Unlike many other pests, they are unlikely to venture indoors. Instead, they are attracted to outdoor spaces like yards, ponds, lakes, and pools.
The primary attractant for female horse flies – the biting ones – is the need for blood. They locate hosts, both animals and humans, by sensing heat and sweat emanating from bodies. Carbon dioxide and movement also play a role in attracting these flies. Dark clothing can also be more attractive to horse flies than lighter shades.
Effective Strategies: How to Keep Horse Flies Away
To minimize horse fly presence and bites, consider these practical tips:
- Protective Clothing: When spending time outdoors, particularly in horse fly-prone areas, wear lightweight, light-colored clothing that covers as much skin as possible. Long sleeves and pants can create a barrier against bites.
- Avoid Tall Grass: Steer clear of areas with tall grass, as these are common horse fly habitats. Stick to well-maintained, shorter vegetation areas when possible.
- Skip the Perfume: Strong scents, including perfumes and scented lotions, can attract horse flies and other insects. Opt for unscented products when you plan to be outdoors.
- Distance from Still Water: Stagnant water is a breeding ground for horse flies. Maintain a distance from ponds, marshes, and other still water sources, especially during peak horse fly season.
- Insect Repellents: Apply insect repellents containing DEET or picaridin to exposed skin. These chemicals are effective in deterring horse flies and other biting insects. Always follow the product instructions for safe and effective use.
Keeping Horse Flies Away from Your Pool Area
For those looking to enjoy their pools without horse fly harassment, implement these specific strategies:
- Maintain Pool Cleanliness: Regularly remove any organic debris, such as leaves, algae, and insects, from your pool and the surrounding area. Horse flies can be attracted to decaying organic matter and stagnant water.
- Utilize Sticky Traps: Sticky traps designed for flies can be strategically placed around your pool area to capture horse flies. These traps are non-toxic and can significantly reduce the local horse fly population.
- Horse Fly Specific Traps: Consider using specialized horse fly traps. Some effective designs feature a dark-colored ball that heats up in the sun, mimicking a large animal and attracting female horse flies. Once attracted, the flies are trapped and unable to bite.
By employing these methods, you can significantly decrease the presence of horse flies and enjoy your outdoor spaces, including your pool, with greater comfort and fewer painful bites.
