Straight answers from a licensed New York exterminator and Associate Certified Entomologist (ACE) — serving all five boroughs, in English and Spanish.
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Quick answer: Odorous house ants are tiny brown-to-black ants named for the rotten-coconut smell they give off when crushed. They trail indoors after sweets, especially in wet weather, and form large colonies with many queens. Getting rid of them relies on sweet-based baiting, moisture control, and exclusion — not spraying, which splits colonies and makes them worse.
What do odorous house ants look like?
Odorous house ants are tiny — 1/16 to 1/8 inch — and brown to black, with an uneven thorax and a single node on the waist that is hidden by the abdomen. The surest field test is smell: crushed workers release a strong rotten-coconut odor.
Signs of an infestation
You will see persistent trails along counters, baseboards, and plumbing lines, usually heading to sweets. Numbers often spike during or after rain as ants move indoors.
Biology and behavior
Colonies are large and have many queens and satellite nests. This social structure is why the ants seem to appear everywhere and why repellent sprays backfire: disturbing a colony can cause it to split (bud) into several new colonies.
How to get rid of odorous house ants
Control depends on sweet-based, slow-acting bait placed along trails so foragers carry it back to the many queens. Combine baiting with moisture reduction (fix leaks, reduce humidity), food sanitation, and sealing entry points. Do not spray the trails — it scatters the colony and worsens the problem.
When to call a professional
Because of multiple queens and budding, odorous house ants are one of the hardest household ants to control. A professional can identify satellite nests, deploy the right baits, and manage the colony network for durable results.
A Brooklyn-based, NYSDEC-registered company (Reg. #15140) led by Jorge Bedoya, an Associate Certified Entomologist (ACE). For ants, NYE provides colony-focused ant control matched to the species. ACE-led work comes with a client portal of service reports and photos, fully bilingual service, and no long-term contract.
Odorous House Ant FAQ
How do I know they are odorous house ants?
They are about 1/16 to 1/8 inch, brown to black, and give off a distinctive rotten-coconut or blue-cheese smell when crushed. The waist has a single hidden node.
Why do I suddenly have so many?
Odorous house ants form very large colonies with multiple queens and satellite nests. In wet weather they move indoors in numbers to find food and drier harborage.
How do you get rid of odorous house ants?
Use sweet-based, slow-acting bait along trails so workers share it colony-wide, reduce moisture and food access, and seal entry points. Avoid spraying, which can cause the colony to bud into many smaller colonies.
Are odorous house ants harmful?
They do not bite or sting or spread disease, but they contaminate food and are a persistent nuisance in kitchens.
Where do they nest?
In wall voids, under floors, near water pipes and heaters indoors, and under mulch, stones, and debris outdoors.
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