Which insect bothers you the most and why

This is how insects survive the cold winter

Rigid

Insects are cold-blooded animals. If the outside temperature is low, their body temperature also drops - and they have to survive that. To do this, many insects hide underground, in piles of leaves, under tree bark, in masonry, barns, attics, etc. and fall into a cold rigor, also known as winter rigor. It seems to us humans as if they were sleeping or even dead. Ladybugs, for example, which we often find lifeless in large groups in window frames in winter, have moved here to hibernate.

Another example: ants hide in the depths of their burrows in the ground in winter; this is the only way for the state to survive the cold temperatures. Your hill above the earth serves as protection against frost. Ground beetles also retreat into the ground: depending on the type of beetle, as larva or as imago - as the adult animal is called - in cold rigor.

In cold rigidity, the body functions are reduced to a minimum; when the outside temperature rises, the animals wake up again. However, if the temperature falls below the bearable minimum in the course of winter, the insects freeze to death.

Antifreeze

In order to prevent exactly that, some insects dig deep into their bag of tricks: they produce an endogenous antifreeze. Ladybugs, for example, have glycerine in their “blood” or in what is known as hemolymph. The glycerine content in the body fluid lowers its freezing point, so that it does not freeze at just below freezing temperatures. This is vital: when water freezes, ice crystals form, which in turn destroy the tissue. Some types of mosquito also rely on the frost protection strategy so that they survive the cold temperatures.

Honey bees shiver warmly

The so-called summer bees only live for a few weeks and are responsible for collecting nectar and pollen as well as rearing new bees during this time. The bees that hatch in autumn live up to 9 months and are there to bring the colony through the winter. Together with the queen, the winter bees cuddle closely together in the so-called winter cluster in the cold months.

It's fair here: Bees that sit outside are always allowed to enter the inner circle and vice versa. With their flight muscles, the bees generate muscle tremors that can heat the beehive to over 30 ° C. Of course, this costs energy: the bees therefore regularly nibble on their honey, which they have specially stored as provisions.

During the winter months, the bees do not shed any droppings so as not to soil the beehive. They collect the excrement in a poop bladder. In the spring the bees then undertake a cleaning flight during which they can finally empty themselves again.

Incidentally, the male bees, the drones, do not survive the winter. They are thrown out of the hive beforehand by the female bees because they have already fulfilled their important task: the fertilization of a queen. At the beginning of the next year, this will still have enough sperm stored to lay new eggs and take care of the next generation.

In the case of bumblebees, wasps and hornets, only queens survive

Ants and honey bees are the only insects that survive the winter as a colony.
The situation is completely different with bumblebees, wasps and hornets: their states only survive for a limited time. The queen lays eggs again before she dies, then she and her people die. From this last generation of breeding young queens and drones hatch before the onset of winter, and they mate quickly. The drones suffer the same fate as the bees: They have had their day after the act of mating and die.

The young queens, on the other hand, are now looking for winter quarters. So they are the only ones that overwinter: in cracks, piles of leaves or in the ground. In spring they look for a new nest, lay eggs and thus found a new state.

Wild bees

In contrast to honey bees or wasps, many wild bees do not form colonies; they are also called solitary bees. For example, they use insect hotels, overwinter in nests on or in the ground, in hollow branches, stems, etc. - either as an adult animal or in the form of a beehive in a cocoon, which then hatches in spring.

Butterflies overwinter in all forms

The moths can overwinter in all their stages, it depends on the species: as an egg, as a caterpillar, as a pupa or as an adult insect.

The first butterflies that we spot in spring are mostly those that survive the cold as adult butterflies: lemon butterflies and peacock butterflies, for example. While the lemon butterflies with antifreeze in their "blood" can withstand colder temperatures, other butterflies take refuge in warmer hiding places such as cellars or attics. Apparently lifeless moths that are found while cleaning up can definitely come back to life in spring!

Some butterflies are so-called migrant butterflies, such as the admiral: He is drawn to warmer regions in winter. For example, some of the admirals, for whom it is too cold in winter in Central Europe, move across the Alps to the warm south. More than 1,000 kilometers! The passes they cross are up to 2,500 meters high and they fly at speeds of up to 20 km / h.

Most butterflies, as caterpillars, seek shelter under bark or in the ground. But if you look carefully, you might also discover dolls hanging on bushes. Butterfly species that hibernate with the help of their eggs lay them down before winter near plants that the caterpillars that hatch from them like to eat.

How we can help the insects

Insects can take a lot! Nevertheless, particularly hard winters can affect them: Then only a small part manages to survive the time until spring. Too mild and moist is also not good for the insects, then the insects or their eggs, larvae and pupae threaten to grow fungus.

It helps the insects when gardens remain “untidy”: Leaves and dead wood left lying around, uncut meadows and nesting aids such as insect hotels are vital for the six-legged friends!