Wild bees are often underestimated. Yet they also achieve remarkable things. They do not produce delicious honey like their famous relatives. Instead, they play an important role as pollinators for wild and cultivated plants. In this way, they not only ensure their survival, but also make an essential contribution to safeguarding our harvests. But wild bees are threatened. Find out here what you can do for these industrious little helpers – because now help is needed from you!
Wild bees stand for biodiversity
Not all bees produce honey? This may cause some people to wonder. In fact, there are many more species besides honey bees. Nevertheless, the so-called wild bees are also extremely important, because they stand for biodiversity! Many people do not even know that these solitary bees exist – and that is hardly surprising. Because they literally fly under our radar. About 75 percent of the species lay their nests in the ground – and are rarely visible to us.
Wild bees spend most of their lives building amazing nests, laying eggs and pollinating plants. Their role in this is far greater than previously thought. A quarter of all wild bees live as specialists in close symbiosis with “their wild plant”. This means that they are dependent on pollen from very specific plants and therefore take good care of their survival. In this way, the small insects ensure the survival of countless wild plants.
Wild bee populations are declining dramatically
There are 750 species of bees in Central Europe, about 560 of them in Europe. Only a few of them still engage in brood care after laying their eggs or form their first primitive states. The 70 bumblebee species in Central Europe (41 of them in Europe) also belong to these state-forming insects, in which the daughters of the mother help to raise the following generations. Bumblebees, in turn, also belong to the bee family.
The much more common species are solitary bees, i.e. the loners among bees. But their populations are declining dramatically: wild bees lack food and nesting resources. Bee conservation is therefore becoming increasingly important. Let’s therefore support the solitary relatives of honey bees and give them back some wilderness.
Helping wild bees – What we can do
Nesting sites as replacement habitats are a small step towards helping bees: wild bees are adapted to a wide variety of nesting habitats and, apart from a few highly specialised species, can be roughly divided into three categories: Old wood nesters, stem nesters and ground nesters. It does not always have to be a self-built insect hotel. You can help effectively with just a little effort.
The old wood nesting beetles use old beetle holes in dead trees. Only the large wood bee (Xylocopa violacea) gnaws thumb-thick tunnels for its nests itself. Old trees with dead but stable wood sections should therefore not be removed, but left in the garden. If you have to fell the tree for safety reasons, you can also place thicker branches and trunk sections upright in a sunny corner of the garden. You can use these pieces of wood just as well for the equipment of a wild bee nesting aid. After pruning in winter, you can also pile up wood and leave it to its own devices. The pile should be sunny from one side and a roof protects it from rain.
Drill holes 5 to 10 cm deep, with different diameters from 2 to 9 mm. Do not drill into the face wood where the annual rings are, but where the bark was originally. Coarse-grained and resinous coniferous wood is unsuitable.
The ground nisters (75 percent of wild bees) need open ground, a patchy sward, sandy areas, steep walls or break-off edges to build their nests in the ground. If you want to help the ground nisters, you could create “sand islands” for them.
The stem nesters build their linear nests in pithy or hollow stems. However, the pith-nesting wild bees only accept individual vertically (!) oriented stems of blackberry, elderberry, thistle, mullein, dog rose, burdock, mugwort and cardoon. Therefore, after the flowering period, cut the upper part of the stems with garden shears to expose the pith.
You can help stem starlings with these alternatives:
Instead of leaving the stems free of flowers, you can cut the pithy stems into long pieces. You should then fix them vertically or at a slight angle in sunny, wind-protected places (e.g. on the fence).
Reeds and straws: You can cut reed mats to 30 centimetres and roll them up. Be careful not to squeeze the straws. Bamboo: Cut off 9 to 20 centimetre long pieces with an inner diameter of 3 to 9 millimetres each behind the thickening. This will then also serve as a back wall (otherwise finish off with some cotton wool). Bundle tightly in empty tin cans or terracotta tubes with the opening facing forwards.
Location: Place nesting boxes in a sunny spot – preferably south-east/south-west exposed – at head height. With hollow stems such as reeds, straw and bamboo, make sure the tunnels are horizontal when using a house wall, fence post or balcony parapet.
Caution. Smooth the surfaces of the wooden hole and bamboo cuttings each time with fine sandpaper. A rabbit wire at a distance of 5-10 cm protects the nesting aid from hungry birds such as woodpeckers or titmice in winter.
In addition, you can also help bees to forage. Read here which bee-friendly perennials in the garden not only please bees and other insects, but also humans.
Ivy silk bee – rare wild bee species in Europe
Wild bees differ from honey bees, but in size the Ivy silk bee (Colletes hederae) is quite comparable to the honey bee. It hatches in late summer, starts building nests in September and often flies until early November. It specialises in ivy pollen as larval food. This rare wild bee species is only very locally distributed in Central Europe. However, it can occasionally occur in masses under favourable climatic conditions and with rich ivy growth. In Europe, it was only known in the Kaiserstuhl region and in the Upper Rhine plain. In the meantime, it can also be found in southern Lower Saxony or at Lake Constance. It was only described as a separate silk bee species in 1993 by Konrad Schmidt and Paul Westrich.
What you need to know about the ivy silk bee
The ivy silky bee is considered the harbinger of autumn. Here is an overview of what you need to know about this wild bee species.
Habitat: Gardens, parks, vineyards, loess walls, slopes, sandy areas with old ivy stands nearby. Nest building: The nests are built in self-dug tunnels deep in loess walls as well as loess and sandy soils - also sand boxes. They usually nest gregariously in colonies, where the numerous females each provide a small nest with up to twelve brood cells. The nests are used for several years. Bee pasture: Ivy (Hedera helix); if ivy is not yet in flower at the beginning of the flight season, it is flexible to switch to other plants such as autumn crocus (Colchicum), goldenrod (Solidago) or toothbrush (Odontites) and other late-flowering plants. Special feature: In adaptation to the late flowering time of ivy, the ivy silky bee hatches only from September onwards and is sometimes still active until the beginning of November. This makes it one of the latest wild bees in Central Europe.
If you want to make your garden even more bee-friendly, learn here how to plant insect-friendly beds.