Termites are social insects that live in colonies. The termite social structure is organized into a caste system based on termites’ unique roles.
Termite Social Structure
There are three levels in the termite caste system:
- Reproductives: The reproductive class includes primary reproductives (the king, queen and swarmer termites) and secondary reproductives (the primary source of egg production supporting the queen, once the colony is established). The king and queen are the colony’s founders and are responsible for increasing the colony’s population. When weather conditions are optimal, the queen produces many primary reproductives (called swarmers or alates) that fly out of the colony to start new colonies.
- Soldiers: Soldier termites are responsible for defending the colony from invaders, such as ants.
- Workers: Worker termites are responsible for building and repairing mud tubes and tunnel walls, feeding other termites in the colony, caring for eggs, removing mold and mildew from tunnel walls, and removing dead termites from the colony.
Termites develop into their assigned caste, reproductive, soldier or worker, to further the development of the colony. These needs continue to evolve based on the colony’s growth rate, size and stability, so each termite may have been a member of at least two different castes at different points in its lifetime.
Behavior of Termites
Termite behavior is determined by the colony’s current need for survival, such as food, protection or reproduction.
Foraging for Food
Worker termites spend a great deal of time foraging for food, and their foraging expeditions can cover a very large area. Formosan termites (a species of subterranean termite) may cover up to 1.5 acres and distances of more than 300 feet while foraging, while other subterranean termite species cover up to half an acre and distances of nearly 260 feet.
Communicating Inside the Colony
Since termites are blind, they communicate through vibrations and pheromones (chemical signals). Pheromones support the termite social structure, as these insects recognize nest mates by scent. Each colony develops its own scent. Termites can secrete pheromones to mark the trail to food or alert the colony to danger.
Some termites also communicate by banging their heads against tunnel walls. The vibrations caused by head-banging notify worker termites when holes in the tunnels need to be repaired. Vibrations also summon soldier termites when ants or other termite enemies invade.
Swarming to Start New Colonies
Swarming is the most visible sign of termite behavior around homes. Termites swarm in order to mate and start new colonies. Subterranean termite colonies can produce thousands of swarmers, while others species of termites, such as drywood termites, produce fewer swarmers and may have less noticeable swarms.