No-See-Ums (Sand Gnats)

No-see-ums, locally called sand gnats, are tiny biting midges measuring just 1/16 inch long — small enough to pass through standard window screens. They are grayish-black with mottled wings visible under magnification. Despite their tiny size, their bites are disproportionately painful. They are most active at dawn and dusk and on calm, overcast days. Unlike mosquitoes, they tend to bite in swarms, leaving clusters of itchy welts on exposed skin.

Multiple itchy, red bite marks appearing in clusters on exposed skin — especially ankles, arms, and neck — are the primary sign. Bites often occur outdoors during dawn and dusk, particularly near marsh edges, wet sand, and shaded landscape areas. You may notice tiny flying insects hovering in clouds near vegetation. No-see-ums are attracted to CO2 and body heat. Unlike mosquito bites, sand gnat bites tend to itch more intensely and may persist for several days.

MBPC targets no-see-ums with barrier spray treatments applied to vegetation, shaded areas, and landscape beds where they rest and breed. We treat damp soil and organic debris near marsh edges, drainage ditches, and low-lying areas of your Myrtle Beach property where larvae develop. Larvicide applications in identified breeding zones reduce emerging adult populations. Our monthly mosquito and biting insect program from March through November includes sand gnat suppression. For properties near the marsh or Intracoastal Waterway, we offer enhanced treatment protocols targeting the higher no-see-um pressure common in these Grand Strand locations.

Standard window screens do not stop no-see-ums due to their tiny size — install fine-mesh (20x20 or finer) screening on porches and windows. Use fans on outdoor living areas; no-see-ums are weak fliers and cannot navigate even moderate air currents. Avoid outdoor activities during peak dawn and dusk hours when possible. Reduce shaded, damp areas in your landscaping where they harbor. Keep landscape beds well-drained and thin mulch to reduce moisture retention. DEET-based repellents provide the best personal protection along the Grand Strand.

No-see-ums breed in moist soil, sand, decaying leaf litter, and mud along salt marsh edges — habitats abundant throughout the Myrtle Beach area. The Grand Strand's extensive salt marshes, tidal creeks, and Intracoastal Waterway create ideal breeding conditions. Adults shelter in vegetation, under eaves, and in shaded landscape beds during the heat of the day. They are most active during calm, humid conditions at dawn and dusk. Properties near the marsh, inlet areas, and low-lying coastal zones experience the highest no-see-um pressure.

Peak activity: Spring-Fall