You sit down on the deck at sunset, and ten minutes later everyone is scratching their ankles. There are no mosquitoes in sight and no buzzing. Just small, hot, itchy welts appearing out of nowhere. If you live in Virginia Beach, Norfolk, Chesapeake, Hampton, Poquoson or anywhere near the water in coastal Virginia, you have met no-see-ums.
Yes, Virginia has no-see-ums, and the coast has a lot of them. They are biting midges in the genus Culicoides, about the size of a grain of sand, and they breed in the wet mud of salt marshes and tidal creeks. They bite mostly at dawn and dusk on calm, humid days from late spring into fall.
What works, based on the research: moving air (they can't fly in a breeze), 20x20 or finer screen mesh, and a proper repellent. In a field test against the main coastal species, DEET repellents gave about 96 to 98% protection. Spraying the whole yard helps less than people expect, because new midges keep flying in from the marsh.
What a No-See-Um Is (and Isn't)
No-see-ums go by a lot of names: biting midges, sand gnats, sand flies, punkies. Entomologists call them Culicoides, a group of tiny flies in the family Ceratopogonidae. The University of Florida puts adults at 1 to 2 millimeters long, with most around 1.5 millimeters. Clemson Extension describes them as about 1/16 of an inch. You usually feel them before you see them.
Only the females bite. They need a blood meal to make eggs. Instead of piercing like a mosquito, a female uses tiny cutting teeth to make a small cut in the skin, injects saliva that keeps the blood from clotting, and drinks from the small pool of blood that forms. University of Florida researchers note that a feeding takes about 2 to 5 minutes. That cutting bite is why it burns right away instead of itching later.
Two common mix-ups are worth clearing up:
- They are not mosquitoes. Mosquito treatments that target standing water, like larvicide dunks in a birdbath, do nothing for no-see-ums, which breed in wet mud instead.
- They don't spread disease to people here. Some websites say no-see-ums carry leishmaniasis. They don't. That disease is spread by phlebotomine sand flies, a different family of insects. In the United States, biting midges are a nuisance to people, not a human disease risk. Their real health impact is on animals: they spread bluetongue and epizootic hemorrhagic disease (EHD) to deer and livestock.
Why Coastal Virginia Has So Many
The species that cause most coastal bite complaints breed in wet, muddy, organic soil that stays damp but isn't underwater: the edges of salt marshes, tidal flats and the muddy banks of tidal creeks. University of Florida entomologists write that the coastal species can reach incredible densities, enough to drive even the most stout-hearted nature lovers indoors. The worst of them, Culicoides furens, is the top coastal pest species in Florida's ranking. Their eggs cannot survive drying out, which is why constantly wet tidal mud suits them so well. Virginia's own Culicoides species were catalogued by Virginia Tech entomologists in a 1971 review of the genus in the state.
Hampton Roads is built around that kind of habitat. The Lynnhaven River and its bays, the Elizabeth River branches, Back Bay, the Poquoson and York River marshes and the edges of the Chesapeake Bay hold miles of tidal mud that no one can drain. Wetland protections rule that out anyway.
Distance matters, but less than people hope. Biting midges are tiny, but University of Florida researchers note that many species fly a couple of kilometers, and some have been tracked up to about 4 kilometers (2.5 miles). If you live within a mile or two of tidal marsh, you are within their reach.
Virginia's wildlife agency sees the same insects from a different angle. Every late summer, the Virginia Department of Wildlife Resources gets reports of hemorrhagic disease in white-tailed deer, a virus that biting midges spread. In its September 1, 2026 release, the department noted the disease runs from late summer until the first frost kills the insects, is historically more common east of the Blue Ridge, and poses no threat to humans or pets. It is a useful reminder that midges are active well into fall.
When No-See-Ums Bite
Timing is the easiest thing you can change.
- Dawn and dusk are the peak. University of Florida researchers describe the heaviest biting around dawn and dusk, with some biting through the night.
- Calm, overcast days extend it. Daytime biting is uncommon unless the sky is heavily overcast and the wind is calm. The University of Florida also notes that in coastal areas many species will bite in broad daylight.
- Wind shuts them down. Clemson Extension notes they are small enough to be blown off course by moving air. A steady breeze off the water is the best protection you can get for free.
- Season: the main coastal species is a warm-weather insect. It builds as soon as spring warms up, stays abundant all summer and tapers off as temperatures drop in fall. In Hampton Roads, expect the worst from roughly May into early fall, and later on mild years.
What Actually Works: The Evidence
There is a lot of folklore about no-see-ums. Here is what the research and extension services actually support.
| Method | What the evidence says | Verdict |
|---|---|---|
| Fans | Clemson and the University of Florida both recommend fans. Florida suggests high-velocity fans in screened porches. Midges can't hold their course in moving air | Works well, cheap |
| No-see-um screen | Standard 16x16 and 18x16 screen lets them through (University of Arizona). Clemson recommends 20x20 mesh or finer. Arizona suggests 30x30 where possible | Works. Finer mesh cuts airflow, so pair it with a fan |
| DEET | In a field test where 96% of the midges were C. furens, a 33% DEET lotion gave 95.9% protection and a 75% DEET liquid gave 97.9% | Works. Use a real concentration and reapply |
| Skin So Soft and other oils | The same study found Avon Skin-So-Soft gave 71.4% protection. It didn't repel the midges. They got stuck in the oily film | Partly works. Better than nothing, not as good as DEET |
| Oil of lemon eucalyptus | In a lab study on a European species, it repelled up to 100% of midges, outperforming DEET in that test | Promising, less field data |
| Picaridin | EPA-registered and widely used, but we found no published field trial against the coastal species. Owner reports are mixed but mostly positive | Reasonable choice, less proven for midges |
| Bug zappers | In a University of Delaware study, only 31 of 13,789 insects killed by zappers (0.22%) were biting flies | Doesn't work |
| Whole-yard spraying | A bifenthrin barrier spray at the maximum label rate reduced C. furens numbers in a Florida study, but the University of Florida calls adult spraying "mediocre at best and temporary" because new midges keep emerging | Reduces numbers near the house. Won't eliminate them |
What Boaters and Beachgoers Report
People who live on boats in marsh country deal with no-see-ums more than anyone. We read through a long Cruisers Forum thread from Florida liveaboards and a TripAdvisor thread from Sanibel Island regulars, plus the Virginia Beach Reddit threads Google surfaces (Reddit blocks automated reading, so we worked from Google's excerpts of those threads). Here is how about 40 first-hand reports break down.
| What people tried | Reports | What they said |
|---|---|---|
| Oily lotions: Skin So Soft, baby oil, body butter, scented body lotions | About 12 positive, 1 negative | The most common "this works" answer. Several said the bugs "get stuck" in the oil, which matches the 1991 study |
| DEET | 3 worked, 3 didn't | Worked for some. Others got bitten through a light DEET spray at Dam Neck or the marina. Concentration and coverage seem to matter |
| Picaridin | 3 worked, 1 weaker | Fans liked that it doesn't smell or damage plastic. One person did better with DEET |
| Wind and distance | 3 | "No wind, no-see-ums." Boaters anchor farther out to catch the breeze |
| Thermacell units and mosquito coils | 4 | Reported to clear a boat cockpit or small sitting area on calm days |
One more lesson came up again and again: the repellent only works if you actually put it on, every time, on ankles and legs, from late afternoon on. Several people blamed their bites on skipping it. And please skip the advice to spray household insecticide on your skin, which also appeared in that thread. It is not made for that.
The Other Biting Flies in Coastal Virginia
Not every bite on a Virginia beach is a no-see-um. If you can see the fly and it is the size of a house fly or bigger, it is something else.
| Insect | What you'll notice | When and where | What helps |
|---|---|---|---|
| No-see-um (biting midge) | Can't see it. Burning bites, often on ankles, wrists and hairline | Dawn and dusk, calm days, near marsh | Breeze, fans, fine screens, repellent |
| Stable fly ("dog fly") | Looks like a house fly but bites hard, usually on the legs and ankles | Daytime, on beaches and around dogs. Breeds in rotting seaweed and wet grass clippings | Long pants and covered legs work better than repellent alone |
| Horse fly, deer fly, greenhead | Big, fast, painful bite you definitely feel and see | Daytime, sunny, near marshes and woods, such as Back Bay and False Cape | Cover up, light-colored clothes, keep moving |
| Mosquito | Visible, buzzes, itchy bump that shows up later | Dusk and night (Asian tiger mosquitoes bite by day) | Dump standing water, repellent, yard treatment |
Virginia Beach residents on Reddit describe the beach biting flies as the ones that end beach days early, bite "right through the bug spray," and swarm dog parks. The University of Florida notes the stable fly picked up the nickname "dog fly" from the way it targets dogs on beaches, and that both males and females bite during the day. USDA researchers have also found that stable flies can ride weather systems much farther than they normally travel, which they believe brings them into Virginia.
What a No-See-Um Bite Looks Like
The University of Arizona describes no-see-um bites as small red welts about 1/8 inch across, or small water-filled blisters, that itch intensely. They often show up in clusters on exposed skin: ankles, lower legs, wrists, the back of the neck and the hairline. Sensitive people can react for several days.
Wash the area with soap and water, use a cold compress or anti-itch cream, and try not to scratch, since broken skin can get infected. An oral antihistamine helps many people with the itch. See a doctor for signs of infection, or for swelling or blistering that keeps spreading.
How to Protect Your Yard and Porch
- Put a fan on the seating area. A box fan or ceiling fan on the porch is the single most effective tool for evenings outside.
- Rescreen with 20x20 or finer mesh on porches and lanais. Pair it with a fan, because finer mesh moves less air.
- Use a real repellent on ankles and legs from late afternoon on, and reapply as the label directs.
- Plan around the peak. Late morning and early afternoon, when the breeze picks up, are the easiest times to be outside near the marsh.
- Skip the bug zapper and the citronella candles. There is no evidence they help with midges.
- Keep shrubs and ground cover near the patio trimmed. Adults rest in low, shaded vegetation between feedings, and thinner plantings near the seating area give them fewer places to wait.
What Professional Treatment Can and Can't Do
Be wary of anyone who promises a no-see-um-free yard near the water. The breeding habitat is the marsh, and it is protected wetland. What treatment can do is cut down the adults resting in the shrubs, ground cover and fence lines around your outdoor living space. That matches the Florida research, where a bifenthrin barrier spray reduced C. furens numbers.
Our Virginia Beach mosquito control program treats those resting areas on a monthly schedule through the season, which helps with mosquitoes and with midges. It works best combined with the fans, screens and repellent above. For how often treatments should run, see how often to spray for mosquitoes in the South.
Key Takeaways
- No-see-ums are biting midges (Culicoides), 1 to 2 millimeters long, that breed in tidal marsh mud.
- Coastal Virginia is prime habitat, and they can fly a mile or two from the marsh.
- Peak biting is dawn and dusk on calm, humid days, from about May into fall.
- Breeze, fans and 20x20 mesh are the best defenses at home.
- DEET gave 96 to 98% protection in a field test. Skin So Soft gave 71%, by trapping the midges in oil.
- Bug zappers don't work, and yard spraying reduces numbers but can't eliminate them near the marsh.
- They don't spread disease to people in the U.S. They do spread hemorrhagic disease to deer.
Sources: N. D. Burkett-Cadena, V. M. Cooper, C. Addae and E. A. Buckner, "Biting Midges, No-See-Ums, Culicoides spp." (EENY-349), University of Florida IFAS, 2025; C. R. Rutledge and J. F. Day, "Biting Midges of Coastal Florida" (ENY-629), University of Florida IFAS; J. Ballew, "Gnats" (HGIC 2489), Clemson Cooperative Extension, 2018; University of Arizona Cooperative Extension, "Something's Biting Me, but I Can't See It"; G. J. Magnon, L. L. Robert, D. L. Kline and L. W. Roberts, "Repellency of two deet formulations and Avon Skin-So-Soft against biting midges in Honduras", Journal of the American Mosquito Control Association 7 (1991); T. B. Frick and D. W. Tallamy, "Density and diversity of nontarget insects killed by suburban electric insect traps", Entomological News 107 (1996), as reported by Iowa State University Extension; Virginia Department of Wildlife Resources, "Suspected Hemorrhagic Disease of Deer Reported in Virginia", September 1, 2026; University of Florida IFAS, "Stable Fly, Stomoxys calcitrans" (EENY-642); USDA Agricultural Research Service, "Trapping Stable Flies at Zoos", 2015; owner accounts from Cruisers & Sailing Forums, TripAdvisor Sanibel Island forum Battle and Turner, A Systematic Review of the Genus Culicoides of Virginia (The Insects of Virginia No. 3), Virginia Polytechnic Institute Research Division, 1971; and Reddit (via Google search excerpts).
Frequently Asked Questions
Yes. No-see-ums are biting midges in the genus Culicoides, and coastal Virginia has plenty of the salt marsh and tidal creek mud they breed in. They are worst in Hampton Roads and along the Chesapeake Bay, but different species also occur inland.
Roughly May into early fall on the coast, with the most biting in summer. The main coastal species builds as soon as spring warms up and tapers off as temperatures drop. Virginia's wildlife agency sees midge-spread disease in deer from late summer until the first frost.
Mostly around dawn and dusk, with some biting through the night. They rarely bite in the middle of the day unless it is heavily overcast and calm, although near the coast some species bite in daylight.
Moving air and a good repellent. A fan or a steady breeze keeps them from landing, and in a field test DEET repellents gave 96 to 98 percent protection against the main coastal species. Long sleeves and pants help, and 20x20 or finer mesh keeps them off a screened porch.
Partly. In a 1991 field test, Avon Skin-So-Soft gave about 71 percent protection, compared with 96 to 98 percent for DEET. It worked by trapping the midges in the oily film rather than repelling them, which is why boaters swear by oily lotions.
Yes. Standard 16x16 and 18x16 window screen is too coarse to stop them. Clemson Extension recommends 20x20 mesh or finer for porches. Finer mesh moves less air, so add a fan.
Almost any contact insecticide will kill the ones it touches, but more fly in from the marsh within minutes, so killing them is not the answer. Wind from a fan, a good repellent and fine screening do far more for an evening outside.
Small red welts about an eighth of an inch across, or tiny water-filled blisters, that itch intensely. They often appear in clusters on ankles, lower legs, wrists and the hairline, and can itch for several days in sensitive people.
Not to people in the United States. Claims that they spread leishmaniasis are wrong, since that is spread by phlebotomine sand flies. Biting midges do spread bluetongue and epizootic hemorrhagic disease to deer and livestock, which pose no threat to people or pets.
If you can't see them, they are likely no-see-ums. If they look like house flies and bite your ankles on the beach, they are probably stable flies, sometimes called dog flies. Large, fast flies that bite hard near marshes and woods are horse flies, deer flies or greenheads.
Photo credits: USDA Agricultural Research Service, public domain, via Wikimedia Commons; Dunpharlain, CC BY-SA 4.0, via Wikimedia Commons.