Bratislava is ready for the main mosquito season; it has already deployed a helicopter to combat the larvae
27. 04. 2023
Bratislava, 27 April 2023 – The city will continue to monitor hatcheries and eliminate mosquito larvae with a Bti during this season. Since March, experts and volunteers have inspected more than 2,600 hatcheries and have carried out more than 60 interventions at various locations in the city, such as Petržalka, Jarovce, Záhorská Bystrica, Vajnory and Podunajské Biskupice. The current combination of rainy weather and higher temperatures has resulted in a higher number of interventions. Due to the increased level of the River Morava and the flooding of the surrounding area, Bratislava deployed a helicopter to combat mosquitoes in Devínska Nova Ves.
The main mosquito season is from April to September. In this period, Bratislava intensively controls the mapped hatcheries. The aim is to prevent calamitous hatching and minimise mosquito numbers. Staff and volunteers go into the field, take samples and mark the observed numbers of larvae in the hatcheries in the application. If excessive levels are found, Bti is applied. This is a selective biological larvicide that uses strains of bacteria that kill mosquito larvae. When applied correctly, it kills 100% of the larvae in the hatchery before the mosquitoes can hatch. Unlike chemical sprays with harmful effects on public health and the environment, Bti works exclusively on mosquito larvae. It has been used in neighbouring Austria for almost twenty years.
Special operation with helicopter in Devínská Nová Ves
A major advantage of Bti is that it can be applied in areas with a higher protection level, where chemical sprays cannot be used and where a large part of the hatcheries are also located, such as areas in the 3rd and 4th protection level around the Morava.
In these locations, after the rains and the flooding of the Morava, dozens of active mosquito hatcheries were observed by staff and volunteers. The floodplain was monitored by drone. A large-scale intervention was ordered across an area of approximately thirty hectares, in which granules were applied from a helicopter.
“This year the control is again being carried out by a contractor and trained employees of the Municipal Enterprise, who use backpack sprayers or spread the larvicide by hand. The biological agent is mainly applied on the ground, but we are also prepared for aerial interventions - by drone or helicopter. We are now using the latter for the first time due to the difficult accessibility of the terrain. After the aerial intervention, we will check the terrain and refill as necessary. Again, the aim is to eliminate the flood mosquitoes before the mosquito larvae have a chance to hatch,“ explained Michal Stano, Mosquito Control Coordinator at the City Hall. At the same time, the Bti helicopter intervention will also be carried out by the Austrians, with whom the city has long been cooperating in terms of mosquito control, increasing the effectiveness of the intervention.
Volunteers can join the fight against mosquitoes again this year
There are more than a thousand regular larger hatcheries and hundreds to thousands of occasional smaller hatcheries which also create suitable conditions for mosquito hatching. Residents can help monitor them and observe the larvae again this year by receiving training and joining the ranks of volunteers. For more information go to web Lovci komárov ↗︎.
It is not possible to prevent mosquitoes completely, but Bratislava is focusing on the timely elimination of as many larvae as possible, so that the number of biting mosquitoes is as low as possible. It is not possible to intervene in gardening settlements, in areas with level 5 protection, in forests or water protection zones (Čunovo, Sihot', Pečňa).
The city has prepared a tablet Bti for garden and house-owners/tenants this year that can be collected at the Residents Services Department at City Hall, Primaciálne námestie 1, as well as at any of the 15 local offices in the city districts (except for Rača and Petržalka).