- decreased wasp population in Bavaria due to spring showers
In the latter part of summer, wasps have been known to cause nuisances, but this year, they seem to be less prevalent in Bavaria compared to previous years. During the "Insect Summer" citizen science project in June and August, fewer wasps were spotted than in the same period in 2023 and 2022. Insect expert Tarja Richter from the conservation organization LBV in Hilpoltstein attributes this to the rainy early summer.
The LBV, along with the German Nature Conservation Association (NABU), encouraged German residents to monitor and document insects in their proximity for two hours each in June and August. The purpose of this project is to gather information about the health of beetles, bees, butterflies, and other insect species in Germany.
Richter explains that wasps need good weather during the early summer to establish their nests. The worker wasps then venture out to catch insects as food for the larvae. This year's heavy rain likely led to smaller or delayed nest construction, according to Richter.
Several wasp species inhabit Germany, but only the common wasp (Vespula vulgaris) and the German wasp (Vespula germanica) tend to become a hassle at ice cream stands and barbecues. This is especially true in late summer, typically from August to mid-September, when most wasps have hatched and are searching for food.
Richter explains that adult wasps subsist on nectar, plant sap, and fruit. The larvae also produce a sugary substance that the worker wasps consume. However, in late summer, this food source becomes scarce. "Then they come to us," said Richter, referring to the attraction of sweet foods and drinks such as ice cream, juice, and fruit cake.
To deter wasps, Richter suggests spraying them with water from a spray bottle. "They fly away because they think it's raining and they want to clean themselves first," she said. It's also recommended to place a plate with, for example, sliced grapes far from the dessert table as a distraction. This plate should be placed before serving the dessert.
The results of the "Insect Summer" project in 2024 are yet to be revealed.
The decreased prevalence of wasps in Bavaria this year could potentially be good news for other insect species that share 'The nature', as less competition for food sources may benefit them. Richter highlighted that wasps require good weather during early summer for effective nest construction, which was compromised by the heavy rain this year.
