What bit me in Massachusetts?
18 biting or stinging species have verified records in Massachusetts. The fastest way to narrow it down is where on your body the marks are and how they are arranged — below the knee in clusters points to fleas or chiggers, lines on uncovered skin point to bed bugs, scattered single bumps point to mosquitoes. Bite season here runs roughly April to October.
Active around now in Massachusetts
- Honey bee
- Carpenter ant
- Bald-faced hornet
- Deer tick
- Mosquito
- Paper wasp
- American dog tick
- Yellowjacket
- Lone star tick
- Yellow sac spider
Recorded biting species in Massachusetts
| Species | Looks like | Where on body | Records | Peak |
|---|---|---|---|---|
| Honey bee sting | single | feet — bees are often stepped on in clover, hands | 10,289 | June to September |
| Carpenter ant bite | single or a few | hands, arms | 2,046 | April to July |
| Bald-faced hornet sting | often several — the colony defends aggressively | head, neck | 1,834 | August to October |
| Deer tick bite | single, usually in a skin fold or hairline | groin, armpits | 1,591 | April to July |
| Mosquito bite | single bumps scattered over exposed skin | ankles, lower legs | 1,408 | June to September |
| Paper wasp sting | usually single | hands, head | 1,300 | June to September |
| American dog tick bite | single | scalp, neck | 1,248 | April to July |
| Yellowjacket sting | single or several — this wasp can sting repeatedly | hands, face | 575 | August to November |
| Lone star tick bite | single, sometimes dozens at once when larval "seed ticks" swarm | legs, waist | 138 | May to July |
| Yellow sac spider bite | single, sometimes two nearby | neck, arms | 91 | April, June, December |
| Horsefly bite | single, occasionally two | legs, back | 85 | June to August |
| Flea bite | clusters of three or four, or short irregular groups | ankles, shins | 29 | August, October, November |
| Scabies rash | symmetrical, in finger webs, wrists, waistline, armpits and groin | finger webs, wrists | 17 | July |
| Bed bug bite | lines or zigzags of three or more — the classic "breakfast, lunch and dinner" | arms, shoulders | 13 | July |
| Deer fly bite | single or a few, often on the scalp and neck | scalp, neck | 9 | May to July |
| Black widow spider bite | single site | hands, forearms | 4 | June, July, September, October |
| Wolf spider bite | single site | hands, feet | 4 | May, June, September, October |
| Head lice bites | concentrated behind the ears and at the nape | scalp, behind the ears | 4 | July |
Record counts come from the GBIF biodiversity database and reflect how often a species is reported and identified in Massachusetts. They are a guide to what is plausible here, not a census — and they say nothing about how likely you are to be bitten indoors.
Bite season month by month
Of the 18 species recorded in Massachusetts, 18 are active in June — the peak of the local season. The humid continental climate here is what sets those boundaries: species that need warmth disappear at the edges of the year, while the indoor ones do not care.
| Month | Species active | Notably |
|---|---|---|
| January | 3 | Scabies, Bed bug, Head lice bites |
| February | 3 | Scabies, Bed bug, Head lice bites |
| March | 6 | Honey bee, Lone star tick, Flea |
| April | 13 | Honey bee, Carpenter ant, Deer tick |
| May | 16 | Honey bee, Carpenter ant, Deer tick |
| June | 18 | Honey bee, Carpenter ant, Bald-faced hornet |
| July | 18 | Honey bee, Carpenter ant, Bald-faced hornet |
| August | 18 | Honey bee, Carpenter ant, Bald-faced hornet |
| September | 16 | Honey bee, Carpenter ant, Bald-faced hornet |
| October | 12 | Honey bee, Bald-faced hornet, Deer tick |
| November | 5 | Yellow sac spider, Flea, Scabies |
| December | 3 | Scabies, Bed bug, Head lice bites |
Narrowing it down in three questions
- Where on your body? Below the knee in clusters points to fleas or chiggers. Uncovered skin — arms, shoulders, neck — points to bed bugs or mosquitoes. Along a sock line or waistband is close to diagnostic for chiggers.
- How are they arranged? A line or zigzag of three or more suggests bed bugs. Scattered single bumps suggest mosquitoes. A curved group with white pustules the next day means fire ants.
- Indoors or outdoors, and when? Bites that appear overnight in one specific bed are a different problem from bites after an afternoon in tall grass. In Massachusetts the outdoor season runs April to October; the indoor species run all year.
Stings rather than bites in Massachusetts
Honey bee, Carpenter ant, Bald-faced hornet, Paper wasp, Yellowjacket are recorded here. Stings differ from bites in one way that matters: they can cause anaphylaxis in sensitised people, and that risk does not depend on how bad previous stings looked. Anyone who has had a severe reaction should carry an adrenaline auto-injector.
Species associated with illness here
- Deer tick bite — Lyme disease, anaplasmosis, babesiosis, Powassan virus (rare)
- Mosquito bite — West Nile virus, La Crosse encephalitis, dengue (Gulf Coast and Southwest, local cases), chikungunya (rare, travel-linked)
- American dog tick bite — Rocky Mountain spotted fever, tularemia, tick paralysis (rare, resolves on removal)
- Lone star tick bite — ehrlichiosis, Heartland virus, tularemia, STARI, alpha-gal syndrome (red meat allergy)
- Flea bite — murine typhus (Gulf Coast, California, Hawaii), cat scratch disease bacteria carried between cats, flea tapeworm (mainly in children who swallow a flea)
Most bites from these species transmit nothing. What matters is the follow-up: note the date of the bite, and report any fever or expanding rash in the following weeks to a clinician, mentioning the bite explicitly.
Seek medical care if
Call emergency services now for difficulty breathing, swelling of the lips, tongue or throat, dizziness or fainting, or hives spreading away from the bite.
- difficulty breathing, or swelling of the lips, tongue or throat after a sting
- a red area that is spreading, hot and painful, especially with a red streak
- fever, chills or feeling generally unwell in the days or weeks after a bite
- an expanding rash appearing 3 to 30 days after a tick bite
- a bite that is getting worse rather than better after 72 hours
Year-round in Massachusetts
Weather does not affect everything. Bed bugs, scabies and head lice depend on people rather than season, so a bite pattern in January in Massachusetts points to those first — see what is biting me at night.
Get a photo assessment in the app
Everything above is free to read. The app adds what a page cannot: point your camera at the bite and get an assessment of the most likely cause, a severity read, and a day-by-day care plan — including the specific signs that mean you should be seen.
iPhone and iPad. Free to download.