Termites are the most social insects in the world. They have a special organization inside their colonies and behave according to a specific order.
This organization between termites is regulated by many means of communication. You could wonder how termites – blind insects – can communicate; but it is true, yes they communicate using some chemicals called pheromones.
- What are pheromones?
- What is the origin of pheromones?
- How termites are socially organized?
- What is the behavior of termites?
- What is the importance of pheromones in the life of termites?
- Are there other ways of communication between termites?
- How can pheromones be used in termite extermination?
Definition of Pheromones
Pheromones are, generally, chemical substances used by insects (or even plants) for many reasons, like trail marking, defense, reproduction, organization of the caste, among other things.
Termite pheromones are secreted from exocrine glands which exist in the abdomen of termites. As for termites, pheromones are usually similar to a blue ink. So when you discover a blue trail with a significant smell, you have to follow it and see if your house structure really suffers from a termite infestation.
The Origins of Pheromones
Pheromones were first discovered by Peter Karlson and Martin Lüscher in 1959. These chemical substances are considered chemical messengers which were called “alarm substances” by Adolf Butenandt, Jean-Henri Fabre, Karl von Frisch and Jean-Henri Fabre.
Pheromones are similar to hormones and their chemical composition is based on a carbon chain to which are attached several atoms of hydrogen so it is most like proteins.
These substances are catalyzed by enzymes which are the exocrine glands at the bottom of a termite and detected by receptors which are antennae at the head of termites.
The social organization of termite colonies
Termites are social insects which live in colonies and for that, they must have their own “law” to manage their social life and guarantee the survival of the colony. This law is called – by entomologists – the social organization, and it is really typical.
The study of termites allowed us to discover a very special social organization of termites as they organize their troops in such an amazing way:
- Workers: worker termites present the power of the colony. They have several activities to assure the persistence of other termites such as feeding termite soldiers, feeding the king and the queen, taking care of the eggs, building walls (defensive activity) on the boundaries of the colony and finding food sources.
The physical structure of a worker termite is simple: they look pale-off white, with yellow round head and dark antennae. Also, they don’t have mandibles.
- Soldiers: soldier termites are the defensive power of the colony; they spend their life protecting the colony from termite predators and inappropriate atmospheres.
This caste of termites, usually, occupy the boundaries of the colony waiting for predators so when an ant discovers a termite colony, they are the first who attack the ant and try to make it leave.
Soldier termites cannot eat by themselves so there must be worker termites to feed them.
The physical structure of soldier termites is more complicated than worker termites: they have an oval black head with sickle shaped mandibles which help them do their defensive role.
- Reproductive Termites: this caste of termites is composed of the fertile males and females which swarm from the native colony to a new place in order to form a new colony.
The role of reproductive termites is necessary in the life cycle of a colony; it guarantees the survival of termites and persistence of the colonies.
Most of reproductive termites are winged, so they swarm to a far places and form new colonies there, such as subterranean termites. A few reproductive termites are wingless, so they cannot swarm away. Therefore, the fertile male and female leave the colony to a near location to form a secondary colony without swarming away.
The reproductive termites become kings and queens and they are specified with longer abdomen than other termites, bigger size, and longer antennae. They also have eyes unlike all the other castes of the colony that don’t have the ability to develop eyes.
Termites, unlike other insects, have a strict behavior. In spite of their amazingly structured social organization, they follow strict rules in their life cycles and they work on it so they can build a termite empire.
Most of the termites get fed by wood and cellulose, so they generally infest wooden structures or dead trees.
Worker termites leave the native colony in search of food sources and they use pheromones to mark a trail so they can mark the way to an important food source.
After finding the source, worker termites recruit other worker termites to feed the colony, so their mission is to bring food and feed soldier termites, the king and the queen.
Termites can also inhibit other termites from going to some sources when they feel a danger coming.
The queen can also use pheromones to inhibit some termites from being fertile so it guarantees the best organization of the colony.
Therefore, as it seems to be correct, the pheromones are the best way of communication between termites and they are the best chemical messengers which guarantee the survival of the colony.
The importance of pheromones in the life of termites
Although termites are blind – except kings and queens – they need a way of communication to assure their social organization and succeed in managing the colony. That’s why pheromones are a necessary hormone secreted by the exocrine glands of termites. It is not just important for the communication of termites, but it also presents other advantages in the life cycle of a colony:
- Marking food trails: when a worker termite discovers a food source, it starts marking a trail to this source using pheromones which will lead other termites to the exact location by smelling it and feeling it with their sensors.
- Regulating the number of the caste: some pheromones can be secreted by the queen to inhibit worker termites from becoming reproductive termites. By that, they organize the colony and keep the order inside it.
- Replacing the queen: when the queen is dead, the king has the ability to secrete a pheromone which can call for fertile females to become queens and that’s how the colony remains managed by a kind and especially a queen.
- Avoiding danger: when a danger is felt among the termites, they start secreting a special pheromone to warn other termites about the danger coming so they have make the option to leave or to stay. It is a working defensive system that helps the colonies survive for years in a domestic structure.
Other Methods of Termite Communication
It is true that termites are smart insects that use pheromones to communicate and they overcame their blindness by this mutation. But they are smarter than you think; they have other means of communication which will make you just SURPRISED!
- Vibrations: this method is commonly used in case of danger. The soldier termite hits the ground with its head – particularly his mandibles – causing a remarkable vibration inside the colony, so other termites become warned and react immediately.
- Sounds: when feeling a danger, a huge colony of termites produce a sound that can be heard from several meters near to the location, causing the warning of other near colonies.
- Instinctive mechanical communication: when building a nest for the colony, there is no chemical communication needed, but the termite has an instinctive ability to bring soil pellets to the construction site and other termites will be mechanically encouraged to do the same job so a nest will be formed in a few days.
How Pheromones Can be Used in Termite Extermination
This amazing mean of communication – the chemical communication via pheromones – can be used by experts in order to exterminate termites. These traces left by the insects can be a clue to their location and may help experts discover the nature, size and location of the termite colony.
Most of the experts rely on finding pheromones trails to start their termite treatment plan.
First, they inspect the pheromones trails and follow them to get to the nest.
Second, they discover the colony and measure the damage so they can move to the termite extermination. In this case, they use special ink pens which contain some ink with an odor similar to the odor of termite pheromones and mark another pheromone trails to a bait station, this should be done very carefully and by a professional to guarantee the best results.
Third, when the termites follow the artificial pheromone marked by the expert, they will get to a new food source, which is a bait station. After that, the poisonous ingredient which will kill the termites will be planted in the bait station and termites would be exterminated in a few days.
Further Resources for Termite Pheromones
- Behavioral bioassays of termite trail pheromones : Recruitment and orientation effects of cembrene-A inNasutitermes costalis (Isoptera: Termitidae) and discussion of factors affecting termite response in experimental contexts. – J Chem Ecol
- Nonadecadienone, a new termite trail-following pheromone identified in Glossotermes oculatus (Serritermitidae) – Chem Senses
- How Do Worker Termites See? – MyTermiteTreatmentCosts.com
- Termite Trails – University of Kentucky Department of Entomology
- Researchers Find ‘Key Ingredient’ That Regulates Termite Caste System – North Carolina State News