The nesting habits of subterranean termites can be described in two basic groups: 1. Multi-site nesters (Heterotermes, Schedorhinotermes, Mastotermes) 2. Central-site nesters (Coptotermes, Nasutitermes) Multi-site nesters utilise many timber sources for nesting and they can move quickly to a new food source. They are able to reproduce quickly using “ergatoid” or multiple reproductive forms so each new timber source located becomes a potential nest. These species can therefore set up multiple colonies within the same house. Central-site nesters generally have one large queen and a central nest position. The activity of the colony is to bring back food to this nest. They can infest multiple timber food sources but cannot reproduce within those timbers. When a moisture source is available within a house structure, central-site nesters often establish their colony inside the building without any ground contact.
Central-site nesters show definite seasonal variation with their foraging behaviour. Generally, foraging activity is greater in the warmer months and reduced in cooler winter periods. The available moisture can also limit the foraging activity of these species. Generally distant food sources show greater foraging activity in warmer periods and food sources close to the nest are more active in the cooler months. Multi-site nesters do not have the same restrictions as they can move their nest to adjacent food sources. This type of foraging activity often leads to splitting of one colony into several distinct colonies within the same area. The activity of these species quickly multiplies in a disturbed environment such as recently cleared land or fire damaged property.
Termites are prone to desiccation. All significant species that attack buildings construct a system of sealed leads that connect the nest to the food sources. Termites can move safely from the nest to the food and back, in an environment that will protect them against exposure to atmospheric conditions, predators and even pesticides. Damage to timber and other materials Timber is the main source of cellulose sought by the commercially important species. Sometimes other, non cellulosic materials are damaged because they are close to feeding activity. Electrical wiring, switches and plug fittings are often attached and severely damaged by termites. When natural food supplies such as trees run out, the termites will turn to timber in service. Using covered mud tunnels to link the food supply to the nest, termites will work in timbers that are hidden in floor, wall or ceiling spaces and the damage is often not discovered until structural failure takes place or the termites reveal themselves in some way. Termites can cause extensive damage and more than one colony may attack a building at the same time. In order to minimise the extent of termite damage it is recommended that regular inspections be carried out by a competent and experienced termite inspector. Information and photos courtesy of Bayer Environmental Science.
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