Mound building termites are probably the most advanced architects in the animal kingdom. The main family of termites that build large and advanced mounds are the Macrotermitinae. Although better known from Africa, mound building Macrotermes species are also well distributed throughout tropical Asia as well.
Of these, Macrotermes gilvus is one of the more widespread species in tropical Asia. Their nest repair process is quite representative of many other Macrotermes mound building species as well. When a breach occurs in the nest wall, it normally takes 5-10 minutes for the termites to start reacting and repairing the damage. Also, it depends on where the damage has occurred. A breach near the bottom of the mound is repaired quicker than a breach near the top, because of the lower levels being more densely inhabited.
When a breach occurs, an immediate change in the internal temperature and humidity levels of the mound occurs. This is detected by nearby workers and some hasten to the scene, carrying soil particles in their mouths. Minor soldiers will also begin to amass at the breach and organize themselves into forming a defensive phalanx around the edge of the breach.
Above – Minor soldiers will usually be the main defenders around a breach. Here they are gathered on a fungus comb.
Above – Minor soldiers also take up positions around the edge of the breach, forming a loose phalanx formation.
Major soldiers on the other hand, take up positions further in, away from sight. They almost never show themselves, because of their relatively low numbers and flank vulnerability, and their task is to blockade narrow tunnels and galleries further in, with their large heads. This is the general behavior of major soldiers but it does differ in a few species. In other more aggressive Macrotermes species like M. carbonarius, the major soldiers are out in full force in the event of any breach (because they are the main nest defenders).
Above – The workers are hard at work repairing the damage. Major workers predominate, although there are also many minor workers in the mix.
Above – As more termites gather at the scene, the damage gets repaired quickly.
As more and more workers proceed to the scene of the breach, the repair becomes more and more frantic. Major workers bear the brunt of the work, as this is their main role, but there are also many minor workers that will participate at the same time. The damage is repaired from the inside out, and as workers fixate soil particles one on top of the other nearer towards the edge of the breach, the minor soldiers move back in while the spots where the soldiers previously stood are then “bricked” over with fresh soil particles.
Under normal circumstances, a small breach of several inches width is nominally repaired within several hours (sufficient repair means not to allow any intruders in and re-establish the humidity and temperature level inside the mound), although total repair may take a whole night to complete, if the damage is more severe.