Roach bait is a pest control tool used for the extermination of cockroaches at indoor locations. The effectiveness of this method of pest control exploits the cannibalistic tendencies of cockroaches.

Mechanism

Cockroaches live in nests. As such, killing a few roaches that happen to wander into a trap is an inadequate means of controlling the pest. Even if all adult roaches outside the nest are killed, some live eggs will remain in the nest and eventually hatch, leading to an exponential growth problem.

Instead of trapping any roaches, the bait contains concentrated poison with a slow-release mechanism. In the case of boric acid, the bait is a slow-acting toxin which adheres to its body. The roach then returns to the nest, eventually dying. However, the poison remains in (or on) its body, which the other roaches in the nest soon eat, becoming poisoned as well. In this way, each roach not only becomes a dead roach crawling, but also acts like a Typhoid Mary to the other roaches. Eventually the nest fills up with poisonous carcasses, turning the nest itself into a death trap.