House mosquitoes are not very selective when choosing their breeding sites. Basically, any standing or slow-flowing pool of water that lacks aquatic or marsh plants is suitable. They prefer small artificial bodies of water, such as rain barrels, clogged drains, clogged gutters, water-filled watering cans, toys, buckets, vats, ponds, and mini-ponds without plants, as well as open seepage pits and cesspools. Since these insects have a short flight range, they establish their breeding sites in close proximity to their human hosts.

In addition to external characteristics, house mosquito species differ primarily in their egg-laying behavior. Unlike their relatives, the floodwater mosquitoes, which lay their eggs on the ground in floodplain areas and depend on flooding for the larvae to hatch, house mosquitoes stick their egg clusters together to form so-called "egg rafts" directly on a calm water surface. This makes house mosquitoes completely independent of flooding. All species require standing water and an air temperature of at least 18 °Celsius for their development and hatching.

The hatched larvae hang with their abdomen on the water surface, where they breathe atmospheric air through a breathing tube. With specially designed mouthparts, they swirl water around themselves, filtering out small and tiny particles as food. Depending on the water temperature, the development from egg to winged insect varies in speed. The development time can vary from a few days to several weeks, depending on the temperature.

The mated female house mosquito overwinters in basements and storage rooms. This means that these domestic pests can become a nuisance in homes early in the spring. House mosquitoes are strictly crepuscular and nocturnal animals and do not migrate very far. They therefore usually bother humans in the evening and at night.

The Asian tiger mosquito (Aedes albopictus) originates from Southeast Asia, where it is one of the most common and widespread mosquito species. It has managed to bridge even large distances between continents, mainly with the help of international trade. In addition, warmer temperatures caused by climate change have led to tiger mosquitoes spreading to temperate regions of Central Europe. For example, the increase in heavy rainfall events followed by warm, dry weather can cause mosquito populations to rise, as the conditions for mosquito larvae to develop in the resulting pools of water are particularly favorable, just as they are for native mosquitoes.

Tiger mosquitoes are generalists, i.e., although they prefer to bite humans and other mammals, they do not spurn birds, amphibians, and reptiles as blood hosts. In tropical countries, they are known to transmit viruses between humans and animals.

Measuring 0.4–0.9 cm, the tiger mosquito is much smaller than our native mosquitoes. The black and white stripes on the body and legs of these insects are striking. Tiger mosquitoes fly and bite during the day.

Another invasive mosquito species that, like the tiger mosquito, can transmit diseases is the Japanese bush mosquito (Ochlerotatus j. japonicus).

Invasive mosquito species are under observation in Germany. The "Mosquito Atlas" project supports ongoing research on mosquito monitoring in Germany. Mosquitoes from all over the country are collected as part of the project. Citizens can also report their findings here. For more information on invasive species and the Mosquito Atlas, see the list of links below.

The city of Mainz, together with other municipalities, districts, and Baden-Württemberg located along the Rhine, is a member of the "Kommunale Aktionsgemeinschaft zur Bekämpfung der Schnakenplage e.V. (KABS e.V.)" (Municipal Action Group for Combating the Mosquito Plague). KABS was founded in 1976 to combat flood mosquitoes, i.e., the real "Rhine mosquitoes" on the Upper Rhine. Their tendency to migrate and bite, combined with their long flight ranges, led to considerable infestations at the time, which are now prevented by the use of biological agents based on Bacillus thuringiensis israelensis (Bti). The use of these agents on native mosquitoes is carried out with care to preserve a certain basic population, as both the larvae and the flying insects are part of the native food chain.

The KABS's remit has now been expanded to include the control, eradication, and research of houseflies and invasive mosquito species. For further information, see the list of links below.

Public land is monitored by KABS on behalf of the city of Mainz and, if necessary, treated. On private land, you can take preventive measures and act yourself:

Remove all unnecessary water containers. Water often collects in objects that are temporarily not in use, e.g., empty flower pots or vases in the cemetery. Clear these away or turn them upside down.

Clear flat roofs of objects that can hold even small amounts of water, e.g., plastic sheeting. Defective rainwater drains should be repaired immediately.

Keep rain gutters clear or cover them with nets from specialist retailers.

Cover any water collectors that are needed (e.g., rain barrels).

Regularly change the water in bird baths, flower saucers, or other necessary water containers.

Plant vegetation in ponds and mini ponds and along their banks. This quickly attracts dragonflies to lay their eggs, and the dragonfly larvae eat the mosquito larvae. As a rule, a natural balance between mosquito larvae and their predators is established within a year.

Preserve the habitats of birds and bats that eat flying insects. Plant and maintain dense, tall shrubs and trees for this purpose.

Bti tablets should only be used in private areas in urgent cases and then sparingly if the above measures are not effective. These are available from specialist retailers or free of charge from the Mainz Environmental Store and local authorities, while stocks last.

The term "Schnake," which originates from Late Middle High German, is the colloquial term for mosquitoes (Culicidae). Scientifically speaking, snakeflies belong to a different insect family (Tipulidae). They do not suck blood at all, but feed only on exposed plant sap and water due to their very soft mouthparts.