Definition
Many insects communicate through scent, releasing chemical signals called pheromones to attract mates, mark trails, or signal alarm to others of their species. A pheromone trap takes advantage of this by using a lab-synthesized copy of an insect's own pheromone as bait, usually held in a small lure inside a sticky trap or funnel trap. When a target insect picks up the scent, it follows it straight into the trap and gets stuck or captured, often thinking it's tracking down a mate.
Because pheromones are chemically specific to a single species (or a small group of closely related ones), pheromone traps are highly targeted — a trap baited for pantry moths won't attract clothes moths, and vice versa. That specificity is exactly what makes them useful. Pest control professionals rely on pheromone traps mainly for monitoring: placing traps around a property and checking catch counts over time to detect activity early, confirm a species identification, gauge how large a population is, and measure whether a treatment is working. They're also used for mass-trapping in some cases, where enough traps are deployed to meaningfully reduce a population directly, which is common with pantry pests like Indian meal moths in stored-food areas.
- A sticky pheromone trap in a pantry that starts catching moths tells you there's an active infestation worth investigating, even before you've spotted larvae in the food itself.
- Monitoring traps placed during a treatment program let a technician track whether catch numbers are dropping over successive visits.
- Because they're species-specific, a technician can also use pheromone trap results to help confirm exactly which pest they're dealing with.