The varroa mite threatens bee colonies

In Europe, it's finally spring, sunshine and blossoming nature. This also marks the start of the new bee year, when the striped insects begin to collect pollen and nectar. Bees play an important role in the ecosystem as they are pollinators and play a central role in the reproduction of many plants. But these small, industrious animals are endangered.

The varroa mite (varroa destructor), which lives as a parasite on honey bees in hives, has struck particularly hard this year, destroying numerous bee colonies. Beekeepers in many regions of Germany are reporting dramatic losses.

A varroa mite sits on the brood cell of a honeycomb. Varroa mites live in almost every bee colony; they are often responsible for the collapse of colonies in winter. The small arachnids multiply in the honeycomb cells and suck on larvae or adult bees. The young bees can become crippled and in some cases diseases are transmitted. If there are too many mites, the colony dies.

The first fruit blossoms in March and April are highly coveted by bees and other insect species. However, climate change and the increasingly mild winters are also creating ideal conditions for varroa mites, as bee colonies hardly ever take a break from brooding. This allows the mites, which only thrive in the brood cells, to multiply.

Matthias Rettig's bee colonies have also been weakened this year by the parasite, which was introduced from Asia around 50 years ago. The beekeeper from Trier has 30 colonies scattered across the region. He wafts smoke over a hive to calm the insects so he can check the exact condition of the colony.

In addition to chemical control of the varroa mite, there is another clever method to deploy the queen bee. She can be placed in a cage so that she does not lay eggs for three weeks. As the mite reproduces exclusively in the bee brood, a break in bee breeding also interrupts the growth of the mite population.

However, the rising temperatures in Germany have long since attracted new pests. Experts are particularly concerned about the spread of the Asian hornet, as the already endangered honey bees are also on the predators' menu. The invasive hornets can destroy entire bee colonies in a very short time.