Bees that traditionally live in underground corridors are little known insects. They usually belong to four families: Colletidae, Andrenidae, Megachilidae, and Halictidae. But they are also found in other families. For example, bumblebees that live in the ground are in the Apidae family. Ground bees do not form a colony, live alone in burrows, and differ in appearance from honeybees. Amazingly, researchers have identified more than 21,000 species of bees on earth1, many of which have not yet been studied at all. Statistically, 70 per cent of these bees live underground.
Appearance of ground bees
Ground bees are different from their domestic honeybee relatives. They are generally smaller in size. Their body length ranges from 8 to 19 mm. Males have almost no differences with females. They have dense fur, which indicates a life in difficult underground conditions. In contrast to the domestic inhabitants of hives, insects living in the ground are black in colour. Their wings are violet-coloured, slightly curved and their head is dark brown.
Where they live
Despite the large number of types, none of them are domestic. All populations are classified as wild. They inhabit the entire planet, with the exception of South America, Australia, Madagascar and some countries in Africa. Representatives of the families settle on the edge of a field or in a forest area. In the USA, these families are particularly popular and often annoy landowners by building underground cities consisting of many tunnels.
Species of ground bees
The best known ground bees are:
Mining Bees (family Andrenidae);
Sweat Bees (family Halictidae);
Mason Bees (family Megachilidae);
Leafcutter Bees (family Megachilidae);
Plasterer Bees (family Colletidae);
Mourning bee (family Apidae).
The listed representatives are only a small studied part of the bees living in undergrounds.
A way of life
In general, representatives of ground bees are solitary. Some may form traditional colonies.
The new generation tries not to live far away from their parents, but to grow and develop together with their brethren.
The basis of the arthropod family is traditionally the queen, who is the first to find a suitable burrow and lay larvae in it to give birth to new individuals. As they develop, they begin to collect pollen and deposit it in holes in the ground, which are reinforced with saliva. The queen dies after giving life to her offspring.
Nest
The material for creating their own dwellings is soil, from which bees create deep burrows. The burrows dug by the insects are somewhat similar to deep tunnels. Numerous oval-shaped dead-end hollows branch off from them in different directions. In some of these cavities bees store honey. The advantage is that the nectar is stored in such a chamber as in a container, without losing its flavour and beneficial qualities.
First of all, the insects dig an oval tunnel, then create a cell in it, and the freed earth is mixed with saliva. The bees put this mixture in a circle, tamping it with their legs, and then treat the entire surface with a special substance – the secretion of abdominal glands. Once the surface has hardened, the dwelling is securely protected from moisture and other weather conditions.
But it is not only the earth that attracts ground bees to build homes, they often settle in the bark of trees or in crevices in the walls of a wooden house. A tree leaf or a crevice in a rock often serves as a home.
Generational change and offspring
The ground is also the basis for brood rearing. The burrow is lined with a waterproof layer consisting of saliva, soil and secretion produced by the abdominal glands. Bees store their larvae in this tough substance, from which future bees emerge.
The role in nature
Ground bees are an essential part of nature. Their main benefit is pollination of plants. When we say that the number of bees on earth is decreasing due to climate change, reduction of their habitat, use of pesticides, we are talking first of all about wild bees. And most of them live underground.
Of course, the honeybee is more familiar to all of us, but the main role in pollination is played by wild bees. They are the best adapted to local conditions and are the most efficient pollinators. And at least a third of the world’s agricultural crops depend on these hard-working little pollinators.
Can ground bees harm humans
Insects do not cause any harm to humans. Sometimes they live in small colonies in dachas or private houses, but they never attack if they are not touched. In rare cases, the ground bee may make a nest in the wall of a house or in the root system of a plant, but in most cases they are completely harmless.
Conclusion
There are so many species of ground bees. All together they play a great role in the ecosystem. One of the important functions of earth bees is to pollinate plants.
1. https://en.wikipedia.org/wiki/Bee