(Paravespula germanica and Paravespula vulgaris)
Out of all of the different species of wasp, only the conspicuously black and yellow German wasp, which is 13 to 20 mm long, and the very similar common wasp can become troublesome. The two types are barely distinguishable for laypeople. They live in communities which last for a year; in other words, the workers die in the autumn and only the young, fertilised queens survive the winter and form a new nest the following year. The wasp nests are usually found in the ground; however, they can also be constructed artificially from a paper-like mass in roller shutter boxes, lofts or similar places. Wasps are fans of sugar and it is often when they are looking for this that they encounter people. Normally, wasps only use their sting against people in an emergency, when they are in distress or for self-defence.
When they appear frequently, wasps can be very troublesome as they feed on fruit, juices, cake, meat, etc. When they are found in facilities which process foods, they are considered to be a pest from a hygiene point of view as they can transmit pathogens and mould spores. Their stings are very painful and are extremely dangerous under certain circumstances for people with insect sting allergies.
To prevent wasps from causing a nuisance, you should firstly remove attractive substances (fruit, fruit waste, jam, etc.) or keep them locked away. If you notice a wasp nest near apartments or houses, it is advisable to enlist a professional pest controller to eradicate it as wasps can react very aggressively if they are disturbed or feel threatened. As wasps can eliminate insects themselves and therefore should be considered to be useful, you should avoid eradicating them if possible. If the people at your site cannot tolerate them (e.g. if they are living at a window which is opened daily), they should be relocated by a specialist.