How do pests communicate?

We all know that humans are not the only animals that communicate with each other. Barking, chirping, howling – almost any noise an animal intentionally makes can be considered communication. But sometimes you need to know how pests communicate to understand how to effectively treat infestations, like breaking the code of an enemy army. So with that in mind, here are some of the amazing ways common pests communicate.

Rats

Rats communicate with each other via both body language and, of course, squeaks, though many rat squeaks are too high to be heard by the human ear. They emit two different kinds of squeaks – low frequency (in the 22kHz range) which are used as alarm cries; and high-frequency squeaks (in the 50kHz range) which are used during play, mating and when eating.

The body language rats use to communicate can vary – for example when they are tense or feel aggressive rats will often puff out their fur and hunch their backs. But they also use teeth grinding as a method of communication. Soft grinding, called bruxing, is most often used to express contentment. Conversely, rats will grind their teeth aggressively to produce sharper cracking sounds. This is called chatter and signals that the rat feels incredibly stressed.

Yellow Jackets

Yellow Jackets generally communicate through two main methods: with their antennae or with the release of pheromones.

Wasps use their antennae to smell, hear and touch, and perhaps unsurprisingly, their antennae are incredibly complex. Each antenna has at least 11 short joints and 1 ball-and-socket joint, making it incredibly flexible. But the really amazing part of the antenna is the flagellum, which contains microscopic hearing and smelling organs. Wasp antennae can identify other wasps and find food, and if a wasp identifies a familiar wasp, it may offer the other wasp some of the food it collected to reinforce the social hierarchy of the nest.

Wasps also communicate by releasing pheromones. The queen wasp releases a pheromone that triggers infertility in the worker wasps (which are also female), and when a wasp stings something, it releases a pheromone that signals it is in danger to other wasps. Wasps within around a 20-foot radius will respond by coming to the aid of the stinging wasp. Wasps will also release this pheromone when they die, so you must never swat a wasp near its nest, or you will face the wrath of a whole load of angry stingers.

Ants

Like wasps, ants communicate with pheromones, but ants are much more sensitive to the pheromones, as that is the primary way they communicate (except for a few species which also communicate by rubbing together their mandibles and end segments). Just about everyone at one point in their lives has drawn a leaf through the path of some ants just to watch them scatter in confusion. This is because their pheromone trail, directing one another to a food source, had been disrupted. But despite how easily their trails can be scattered, their pheromones can do amazing things, even to other species of ants.

They mark trails by trailing pheromones on their way back to the nest from having found a food source, but if that trail gets blocked, the ants will scatter (as they did back when you were a child) to find a new route to the food. If an ant finds a good route, it will lay down a new scent, which will get followed by other ants and reinforced on their way back to the nest, eventually resulting in the quickest path from the food to the nest.

Beyond that, ants will also release alarm pheromones when crushed, which will cause surrounding ants to attack. Some ants will even release what is known as ‘propaganda pheromones’ which confuse the ants they are fighting, causing those enemy ants to attack themselves.

Grey squirrels

Squirrels, like rats, use audible signals to communicate, using a series of chirps to indicate everything from laughter to alarm. Their frequency range is normally between .01 kHz. and 10 kHz and they indicate different messages by varying the duration and sound of the chirps. The sounds are then used with tail gestures to form most squirrel communication.

Squirrel sounds can include an almost mousey squeak, chatter and a low-pitched noise, and if you see a squirrel flick its tail, that means it wants you to go away.

Despite all the vocalizations and body language, squirrels are mostly solitary creatures, so almost all of their communications are meant to warn other animals away from their food or territory. So despite how cute it sounds when a squirrel comes up and starts chattering at you, in truth, it is probably being very rude.