Tiny flying insects can turn an enjoyable outdoor experience into an irritating ordeal. Often unnoticed until their itchy bite, understanding these small flies helps in distinguishing them and managing their impact.
No-See-Ums and Gnats: The Relationship
The term “gnat” describes various small, flying insects within the suborder Nematocera. This broad term includes many types of flies, some of which bite and some that do not. No-see-ums, scientifically known as biting midges and belonging to the family Ceratopogonidae, are a specific type of gnat. They are often called by other common names such as sand flies or punkies. While no-see-ums fall under this wider “gnat” umbrella, they possess distinct traits.
Key Distinctions Between No-See-Ums and Gnats
No-see-ums are notably small, typically measuring between 1 to 3 millimeters (about 1/16 to 1/8 inch), making them difficult to spot. Their bodies are often gray to black, and some species exhibit mottled or patterned wings. In contrast, the general term “gnat” can refer to insects ranging up to 0.5 inches, and their appearances vary widely; for example, drain flies are often fuzzy and moth-like.
Their biting habits are a key distinction. Female no-see-ums require blood meals to produce eggs. Their bites are often described as painful, causing immediate irritation and leading to intensely itchy, red welts that can swell up to one or two inches in diameter and may last for several days to two weeks. Many other gnat species, such as fungus gnats or drain flies, do not bite humans and instead feed on decaying organic matter, plant sap, or nectar.
No-see-ums thrive in moist, humid environments, breeding in coastal salt marshes, muddy areas, damp sand, and the wet soil around water bodies or tree holes. Decaying organic matter, like seaweed on beaches, also serves as breeding grounds. Other gnats have different habitat preferences; fungus gnats lay eggs in moist soil, frequently found in potted plants, while drain flies breed in the gelatinous film and standing water found in drains, pipes, and septic tanks. No-see-ums are most active during dawn and dusk, favoring calm, still air conditions due to their weak flight.
Managing These Tiny Pests
Control involves environmental management and personal protection. Eliminating standing water around properties is a primary prevention method, as no-see-ums lay their eggs in moist or wet areas like puddles, clogged gutters, or birdbaths. Installing fine mesh screens, specifically 16-mesh or finer, on windows and doors can help prevent no-see-ums from entering indoor spaces, as their small size allows them to pass through standard screens. Using outdoor fans can also deter them, as their weak flight makes it difficult for them to navigate in breezy conditions.
Personal protection includes applying insect repellents containing active ingredients such as DEET, picaridin, or oil of lemon eucalyptus. Wearing long-sleeved shirts and pants, especially during dawn and dusk when no-see-ums are most active, provides a physical barrier against bites. Avoiding outdoor activities during these peak biting times can also reduce exposure.
If bites occur, immediate relief measures include washing the affected area with soap and water and applying ice or a cold compress to reduce itching and swelling. Over-the-counter topical treatments like hydrocortisone or calamine lotion, or natural remedies such as baking soda paste, aloe vera, or witch hazel, can help soothe discomfort. Avoid scratching bites, as this can prolong irritation and potentially lead to secondary infections.