If you’ve stepped outside on a warm June evening on the South Shore or Cape Cod and felt like you were being bitten by something invisible — you’re not imagining things. Biting midges, better known as no-see-ums, have emerged for the season, and right now in mid-June they are at peak activity across Eastern Massachusetts.

Here’s everything you need to know about these tiny, irritating insects — and what you can actually do about them.

What Are Biting Midges (No-See-Ums)?

Biting midges are tiny, blood-sucking flies in the scientific family Ceratopogonidae, with the most common pest species belonging to the genus Culicoides. They go by a lot of regional names:

No-see-ums (the most common name across North America)
Punkies (the classic New England term, used here since Colonial times — the name comes from the Algonquin and Delaware languages)
Sand flies or biting gnats

The “no-see-um” name dates to the 1840s, a play on “you can’t see them” — and for good reason. Adults are typically just 1 to 3 mm long, making them smaller than a pencil tip and small enough to pass through standard window screens. The image above says it all: next to a mosquito and a penny, they’re barely a speck.

When Do Biting Midges Appear in Massachusetts?

In Eastern Massachusetts — including the Greater Boston area, South Shore, and Cape Cod — biting midges typically begin emerging in mid-June as temperatures warm and humidity rises. That timing lands right around now.

After a cool spring, a sudden warm-up can cause multiple populations to emerge simultaneously. As Cape Cod Museum of Natural History entomologist George Stevens has noted, when the region warms quickly, beach insects and woodland no-see-ums can all hatch at once — compressing what’s normally a staggered nuisance into one intense, hard-to-ignore wave. In a typical year, each hatch’s peak feeding frenzy lasts roughly a week or two before activity subsides.

Activity is heaviest at dusk and dawn, though on overcast days or in coastal areas, biting midges will feed aggressively in full daylight. They are weak fliers and retreat in windy conditions — which is why you rarely notice them on breezy days but get hammered the moment the wind dies down.

Where Do No-See-Ums Breed in Massachusetts?

Biting midge larvae develop in semi-aquatic, organically rich environments — anywhere moist soil, mud, or decomposing organic matter is present. In our area, that includes:

Salt marshes and intertidal zones — the primary coastal breeding habitat. The intertidal sand and mud of Cape Cod and South Shore beaches are prime nursery habitat for Culicoides species that bite beachgoers and picnickers.
Pond and stream edges — the soft, muddy margins of freshwater ponds throughout Eastern Massachusetts.
Decaying seaweed — storm-washed seaweed trapped on beaches creates ideal conditions for egg-laying and larval development.
Wet soil and garden ooze — even backyard areas with persistently wet, organically rich soil can harbor breeding populations.

Females don’t travel far from where they hatched. Most Culicoides species stay within half a mile to a mile of their larval development site — so if you’re getting hammered on your deck, the source is likely nearby.

What Does a No-See-Um Bite Feel Like?

Biting midge mouthparts consist of four tiny cutting blades that lacerate the skin rather than puncturing it like a needle. The result is a sharp, burning sensation at the moment of the bite, followed by a raised red welt. For some people, reactions are mild and pass quickly. For those who are more sensitive, itching can persist for two to three days.

Locals who have lived with no-see-ums for years often develop reduced reactions over time, as the immune system becomes accustomed to the protein injected with each bite. Visitors and newcomers to coastal areas typically react more intensely.

Biting midges in the United States are not known to transmit any disease agents to humans — so while the bites are genuinely miserable, there’s no public health disease risk comparable to mosquitoes here in New England.

Biting Midges vs. Mosquitoes: What’s the Difference?

	Biting Midge (No-See-Um)	Mosquito
Size	1–3 mm	6–12 mm
Passes through window screen?	Yes	No
Peak activity	Dusk, dawn, calm days	Dusk, evening
Bite sensation	Sharp, burning sting	Mild prick
Disease risk in MA	None to humans	EEE, West Nile Virus
Flight range	½–1 mile	Up to 3 miles
Visible in flight?	Rarely	Yes

What Can You Do About No-See-Ums?

The honest answer from entomologists at NC State, Purdue, and the University of Florida is the same: biting midges are very difficult to control, and no single approach eliminates them. But there are several layers of protection that, combined, make a meaningful difference.

Personal Protection

DEET-based repellents remain the most well-documented option for personal protection against biting midges. Products containing 20–30% DEET applied to skin and clothing provide meaningful reduction in biting, though coverage isn’t as complete as with mosquitoes.

Clothing is your first line of defense — light, long-sleeved layers and coverage of ankles and wrists help significantly. Midges can bite through thin, loose-fitting fabric, so tighter weaves work better.

Outdoor Avoidance Strategies

Move away from the intertidal zone at the beach. Beach no-see-ums (punkies) hover close to the wet sand where they breed. Moving even a few yards back from the water’s edge often makes a noticeable difference.
Avoid outdoor activities at dusk and dawn when feeding pressure is highest.
Embrace the wind. On calm, humid evenings, biting midges are at their worst. Even a light breeze dramatically reduces their activity.
Time outdoor events mid-day on warm, sunny, breezy days when midge activity is lowest.

Home and Property Protection

Standard window and door screens will not keep no-see-ums out — their mesh openings are too large. Specialty biting midge screen (sometimes called no-see-um screen) has openings small enough to exclude them, though it also reduces airflow. For screen porches and outdoor rooms where this is practical, it’s worth considering.

Professional pest control sprays using pyrethroid products can reduce adult midge populations temporarily when applied in areas of heavy activity. Ultra-low-volume (ULV) applications in the evening — when midges are actively flying — are most effective. Results are temporary, since midges reinvade treated areas from surrounding breeding sites, but for special outdoor events or heavily impacted areas, a professional application can provide meaningful relief for several days.

Newer Technology: Zone Repellent Systems

Thermacell’s new LIV 2.0 system, launched in June 2026, is notable for Eastern Massachusetts homeowners dealing with both mosquitoes and no-see-ums. It’s the first product in the LIV line to earn EPA-registered efficacy claims against biting midges (Culicoides) in addition to mosquitoes — covering up to 3,140 square feet per hub. We offer Thermacell LIV 2.0 installation and service for residential and commercial properties. Contact us to learn more.

Cape Cod and the South Shore: A Special Case

If you spend time on Cape Cod, you already know no-see-ums come with the territory. The Cape’s extensive salt marshes, intertidal flats, and pond-dotted interior provide some of the most productive biting midge habitat in New England. In some years — particularly after a cold spring followed by a rapid warm-up — the Cape sees intense, simultaneous hatches across both coastal and inland populations.

It’s not in your head, and it’s not a sign that something unusual is wrong. It’s a feature of the landscape. The goal is managing exposure, not expecting elimination.

GreenHow’s Approach to Biting Midge Control

At GreenHow, we’ve been treating pest pressure across Greater Boston, the South Shore, and Cape Cod for years. Our approach to no-see-um management includes:

Barrier spray programs using pyrethroid products that target adult midges in areas of heavy activity around your home or property
Thermacell LIV 2.0 installation for ongoing, EPA-registered zone repellent protection
Integrated property assessments to identify and reduce breeding conditions where practical

No program will eliminate biting midges entirely — that’s the honest truth. But the right combination of professional treatment and personal protection strategies can make the difference between being driven inside and actually enjoying your outdoor spaces this summer.

Ready to take back your yard? Contact GreenHow today for a consultation covering Greater Boston, the South Shore, and Cape Cod.

GreenHow, Inc. is a licensed Massachusetts pesticide applicator serving Greater Boston, the South Shore, and Cape Cod from offices in Newton/Auburndale, Plymouth, and Hyannis.

Sources

NC State Extension: Biting Midges and Their Control (Apperson & Waldvogel, rev. 2022)
Purdue University Extension: Biting Midges: Biology and Public Health Risk
University of Florida IFAS Extension: Biting Midges, No-See-Ums, Culicoides spp. (Burkett-Cadena et al.)
Cape Cod Times: Going Buggy (Susan Milton, June 22, 2000)
Thermacell Press Release: Thermacell Launches LIV 2.0 (June 2, 2026)

Biting Midges in Massachusetts: What Are No-See-Ums and How to Stop Them