During the winter, the ant nest mounds are usually damaged by the Green Woodpecker or have collapsed severely due to snow and rain. Now it is up to the workers to repair the mound.
In the center of the ant nest, there is often a tree stump. The pile of needles is only the visible part of the nest above ground. The nest reaches about the same distance into the ground, where it often extends sideways further than the top of the nest.
The top of the nest is built from fir needles, pieces of wood and branches, buds, pebbles, and resin lumps. This material is collected by the workers from the area around the ant nest; the forest ants are able to carry about 40 times their own body weight. The bodyweight of an ant is 7 to 10 thousandths of a gram (mg).
Inside the nest, there are numerous chambers in which the brood is reared. On the surface, one can observe openings that serve as entrances and exits or have a climate function. In hot weather these are greatly expanded to ventilate the nest, in rain and cold they are closed.
Up to five million ants can live in a wood ant nest. Most of them are workers. In early spring, when the sun warms the ground, living in the ant colony also begins. The ants then crawl onto the top of the nest in dense clumps, warm themselves up and carry this warmth into the nest. This is the only time when the queens are also found on the surface of the nest. They spend the rest of the year in deeper nest layers.
Communication – the chemical speech bubbles
When thousands of animals live together, they must be able to communicate. Ants very often do this with their antennae and with numerous scents. There are about 2000 sensory cells on a single ant’s feeler, with which they can perceive the scents, recognize their nest mates by touch, and measure temperature and air currents. Ants also have well-developed eyesight, with two compound eyes and three small front eyes. They are called compound eyes because each eye is a complex of about 750 rod-shaped individual eyes, the facets. With the forehead eyes, they can perceive differences in brightness.
When an ant has found good prey, it can use scents to tell its fellow ants about it. The ants excrete the scents from various glands all over their body. The ants also use the scents to mark the streets they walk on. In this way, they can find their way around their environment. As forest ants have very good eyesight, they also orient themselves by the position of the sun and by waymarks.