Termites are social insects that live in colonies that can contain in excess of a million termites. They are similar in their habit of living together and their small size to ants but are similar to bees and wasps in both that they have several hierarchies that differ physically and a well developed social order controlled by a Queen. Other members or castes of a termite colony include a king, workers, soldiers, reproductives and alates, all of which contribute in individual ways to growth and protection of the colony.
The queen and king are the original winged reproductives (alates) that left the parent colony during the colonizing or dispersal flight. Their function in the colony is reproduction. After leaving the parents colony, they drop to the ground, shed their winds (de-alate), seek out a suitable nesting site, mate and commence to form a new colony. In the case of many of the subterranean species, moisture and decaying wood are critical during the very early period of development. Timber in moist ground or a rotting scar at the base of a tree is a favoured nesting area for a potential new colony. The king and queen will care for their young until sufficient workers and soldiers are able to take over the duties of the colony. In a well established colony, the queen's duty is solely egg laying, and her daily egg production has been estimated to be over 2,000.
For a species such as the destructive pest termite Coptotermes acinaciformis, to reach a potentially damaging stage from a single pair usually required 3-5 years, but this depends on the site, food and climatic conditions in the chosen environment.
The queen and king live for many years, often over 20, but as the queen ages, her reproductive capacity declines, and the colony may then select developing reproductives to assist the queen and king in their duties.
The workers are males and females whose sexual organs and characteristics have not developed. They make up the largest number of individuals within a colony because they perform all the tasks except defense and reproduction. It is the Workers that do all of the work of the colony - feeding the other castes, grooming and queen, excavating the nest and making tunnels. In working, they chew and eat wood, causing the destruction that makes termites economically important.
They are blind, wingless and sterile, generally about 1/8 to 3/8 of an inch long, and they have a thin body covering (cuticle), which makes them susceptible to drying out (desiccation) when they leave the confines of the colony. Workers are the palest individuals in the colony, apart from the eggs and developing young.
Workers leave the security of the colony or the underground tunnels and shelter tubes only when the humidity is high, and then only to search for food sources.
Soldiers resemble workers in colour and general appearance, except that soldiers have large, well-developed brownish heads with strong mandibles or jaws. Soldiers defend the colony against invaders, primarily ants and other termites.
Soldiers are abundant in species that have a large central colony system, but scarce in some other species. Sightless, they have no compound eyes, except in some primitive species where the eyes are poorly developed. Like workers, their cuticle is thin and they are susceptible to desiccation and seldom leave the environmental security of the colony and shelter tubes.
There are two types of soldiers: Mandibulate and Nausate. Manibulate soldiers have large, obvious jaws or mandibles on the head, and Nausate soldiers have a large head that tapers to a point at the front. Their mandibles are small and hidden by the head when viewed from above. Rather than using their mandibles to attack, they are able to produce a sticky substance to entrap their enemies, leaving them vulnerable to attack.
Reproductives are the sexual forms of a colony, the future kings and queens. Reproductive males and females can be winged (primary) or wingless (secondary or tertiary). Each can produce new offspring.
The bodies of primary reproductives, also called alates or swarmers, vary by species from coal black to pale yellow-brown. Wings may be pale or smoky grey to brown and have few distinct veins. swarmers termites are about 1/4 to 3/8 of an inch long.
Secondary and tertiary reproductives in the colony are generally white to cream-coloured and may have short wing buds. Developed as needed, they replace a primary queen when she is injured or dies.
The young (nymphs) primary reproductives grow by successive skin shedding (molts) until they are fully winged alates in most species. Their cuticles are denser than that of the other castes, being more resistant to drying out when they leave the parent colony to establish new colonies.
Colonising flights, when all of the mature reproductives leave the colony at the same time, often occur in the warmer months when the temperature and humidity outside is similar to that inside the colony, although the timing will differ depending on the species.
Only a very small percentage of swarming termites will survive to initiate new colonies, alates are poor fliers and will often only flutter a few yards until they fall to the ground and shed their wings. Many will be eaten by other insects, birds, etc. The surviving alates will try to find compatible mates and then burrow into the ground to establish a new colony as king and queen.
Alates emerging inside a structure rarely survive but the presence of winged termites, or their shedded wings, inside a home is an indication of a likely infestation and should be addressed immediately.
Alates have straight, bead-like antennae, a thick waist, and a pair of long, equal-length wings, that break off easily. They can be differentiated from adult winged ants that have elbowed antennae, constricted waists, forewings are larger than the rear wings (unequal size), and not easily detached.