Pheromones are chemicals that termites produce in special glands on their bodies. The termites use the pheromones to communicate with each other in their dark environment. One of the situations when termites use pheromones is trail marking.
When termites find a food source, they use a pheromone to mark the trail from the food to their nest. They deposit the pheromone from a gland on the underside of the abdomen. When they return to the nest, the termites recruit other termites to follow the pheromone trail back to the food.
There are some common household chemicals that are similar to the termite trail–marking pheromone. Many people are surprised to learn how common some of them can be. Tests have shown that termites will follow these chemicals just like they follow their trail pheromones. It is easy and fun to use some of these products to demonstrate the termite trail–following behavior.
If subterranean termites can be collected, place a few on a blank piece of paper. Draw a circle around the termites with an inexpensive ballpoint pen. When the termites find the circle of ink, they will probably follow it. If the termites do not follow the line, try using another type of ballpoint pen.
The chemicals in many ballpoint inks are similar to termite trail–marking pheromone. Termites are selective about following lines. It might be an interesting experiment to see if they will follow pencil lines or lines made with markers.
Termite control bait and monitoring systems use the trail–marking behavior of the termites. When foraging termite workers find one of the monitoring stations, they mark the trail to it. Then they recruit other termites to come to the station.
When the termites have started eating the wood monitors, the bait device is placed in the station. This contains the active ingredient that will kill the termites. As long as the termites keep coming and eating, it is important to keep the bait full and fresh. This bait process can eliminate many of the members of a termite colony. In several tests, bait systems eliminated entire termite colonies.