Pheromones are volatile chemicals produced by a given species to communicate with other individuals of the same species to change their behavior. For example, various species use pheromones to attract a mate, to mark territory, or to warn others of danger.
Pheromones are usually effective in tiny amounts.
The pheromones that EPA approved are synthetic versions of these naturally occurring compounds. When these pheromones are released into the air where the males are looking for females, the males become confused and cannot easily locate the females. As a result, many of the females do not mate and lay eggs and there are many fewer offsprings that usual. Effectiveness -The mating disruption technique should be used only to manage low density populations of the European strain of the gypsy moth. In these areas there are enough males and females wandering about for them to find each other without the help of pheromones.