Latin: Osmia sp.
The mason bee belongs to the genus called Osmia. This species builds their own nest, they are solitary bees, meaning that they do not live-in communities, as the honeybee. There are several different types of mason bees, but there is no predominant difference. Neither in behavior, biology, or appearance and they are most often put in the same category i.e. the Osmia family.
It should be noted that there is a big difference between the mason bees and plasterer bee. Mason bees build their own nests using brickwork, where plasterer bee dig their nests into the brickwork, and thereby damaging walls.
Appearance
Mason bees can be easily be confused with other species of bee. They have, like most bees, six legs, transparent wings that lie flat on their backs when resting, and of course feelers on their heads. The mason bees can vary in color, depending on the species. Color wise they can range from completely black with no visible strips to red or yellow strips. Other than that, they are remarkably like an ordinary honeybee in appearance.
It will not be possible to see a mason bee larva, as the larvae live all stages in the masonry nests. They pupate in this nest which is why we only see them as fully grown mason bees.
Biology and behavior
Since mason bees are solitary bees, the females lay their eggs in specially made nests. The female bee even creates this nest of whatever materials are available, like old snail houses, old tree stumps, sand slopes and clay slopes in nature. However, they can also build nests in holes and cavities in masonry or board facing on houses. This is a creative bee; all this bee needs to make a nest is a hole that has access to the outdoors.
The nests are built of sand, stone, clay, and various plant material. The female also store pollen inside the nest. She then lays the egg in the nest and seals it with the same materials. When the egg hatches the mason bee larvae, begins to eat the pollen supply. During this time, the larval skin changes several times, and this stage takes a few weeks. Afterwards it pupates. The adult mason bee emerges from the pupa between spring and summer, depending on the specific species of mason bee.
Damage
The mason bees do not harm either humans or brickwork, despite their resemblance to plasterer bees, which can destroy brickwork. Mason bees exploit existing holes or hollows, but they do not make an existing damage worse with their presence or behavior.
It should of course be noted that the mason bee, like all other bees, has a sting on the back of the body and therefore can sting. However, the mason bee is not considered an aggressive species and they rarely sting. Just stay calm near mason bees, to avoiding a bee sting.
Prevention and control
The mason bees are not as such a pest. Therefore, there is no point in trying to prevent against this specific species of bees or controlling them. They rarely occur in large numbers to be a nuisance. In fact, there are usually a small number of them, especially compared to other species that live in colonies and communities. It can be a unwise idea to prevent and / or control the mason bees, as they, like most bees, help pollinate fruit trees and fruit bushes. Therefore, mason bees are typically considered to be beneficial animals, not pests.
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