Climate change

The mild Winter and its consequences

Since the end of January, attract cranes to the North, much earlier than usual. Other animals suffer from the weather, and some plants bloom even. Is the mild winter weather is a danger for Germany’s nature?

Hardly had the last of December, Wärmerekorden made headlines – he was the warmest in 135 years – came in mid-January the short Temperatureinbruch in the whole of Germany. Sometimes less than minus 20 degrees the Thermometer showed, at the edge of the Alps, the German weather service, in order to then again within a few days to about 14 degrees plus climbing. For the cranes, were the unusually warm Januartage apparently reason enough, from the winter roosts in Northern direction to start. Only three weeks after the last after the South had moved to.

Michael Nickel from the nature and biodiversity conservation Union (NABU) commented on this with the words: “Now it’s already back in the other direction.” And if the Frost but comes back and again it is bitterly cold? Cranes are flexible, so the NABU expert. You could be within one to two days, again in milder areas to Dodge.

Mild temperatures lure insects out

Are more sensitive as domestic insects, ants for example. They can be from the mild winter weather easily fooled. “Already in December were young Hummelköniginnen on the road to Blütensuche,” says Matthias Schindler from the Naturschutzverein “Biological Station Bonn”.

Usually keep the Queens throughout hibernation and crawl up until March from their Hiding – then, if the nature is also plenty of what it has to offer. In a way, the beginning of February. “Bumblebees find now not enough food to eat and consume during the flight from fat, the you actually in the spring for the Nestgründung need”, so Insektenkundler Schindler.

Bumblebee foraging: Usually creep Queens until March from their Hiding

About the consequences of the weakening, one could only speculate. In General, the insects better in Germany at a consistently cold Winter adapted as to mild temperatures with sudden onset of Frost. Bumblebees are already on the retreat. A part of its southern distribution area, you have already lost, as an international team of researchers has discovered. The reason is probably climate change, according to the experts. And contrary to what the researchers expected, the bumblebees does not appear to be new regions in the North inhabited.

There may be Frost in this Winter, not back, which in turn many gardeners concern. They are afraid, that of all pests, such as shield or aphids, from the mild weather could benefit. In the case of aphids there are, however, clear. During the severe frost in mid-January, are expected Blattlausweibchen from last fall, freezing to death be – the norm in Central Europe. Only the eggs they have laid dormant in their Hide on the branches. The Blattlauspopulation will be so until the summer probably, as usual, to develop. In General, there are mild winters, not necessarily more pests, reports Marcus Kühling from the Deutsche Forstverein. Researchers have found that wintering forest pests in the humid and warm weather conditions, even with their consequences, have to deal with. You are then more fungal diseases to the victim.

Young life in Germany’s forests

The large animals of the forest, however, happy about the warm weather, so Kühling. “You can already now rookies, young wild boar, in the forests to watch.” Part of mothers, even not a year old. Ten, twenty years have not given. “It becomes dangerous if again for a long time severe Frost should prevail. It is likely that many young animals simply freeze to death,” says the Forstexperte.

Wild boar-wild sow with newbies: the offspring comes earlier than 20 years ago

With large Wildschweinpopulationen would have foresters, but no problems: “We are pleased, if wild boars in the forest, the ground umwühlen and Schädlingslarven eat.” A different view of the farmers: for years, the rise in the damage to agriculture due to the many wild boars, the on the corn fields real devastation left behind.

Krokusblüten already since the end of January

The most striking deviations from normal cold winters are in the plant world to watch, says Stephan Anhalt from the Botanical garden of Cologne: “Many of the plants are about four weeks earlier than usual.” Asian Zierquitten bloom in Cologne since December, and at the end of January we have the first Krokusblüten shown. Even for Cologne, with his otherwise very mild climate, is a novelty. To Haselsträuchern opened the kitty in many areas already at Christmas for their pollen to be spread – to the chagrin of Allergy sufferers. But this has already frequently given, and the Common hazel makes nothing at all. If now the insects are on the move, is for the shrubs without meaning: For the pollination ensures anyway the Wind.

Obstblüten are at risk

In some of the early fruit trees such as sweet cherries, emerging economies are now already the flower buds. And each additional warm day promotes growth. The downside for the early starter: their resistance to the cold is low. “If it is so in February/March once again properly frosty should be, there may be significant frostbite,” says botanist Anhalt.

Sustained damage to the plants is expected by the Cologne-based expert Stephan Anhalt not, apart from possibly frostbitten flowers. If the Klimatrend, however, continue to have domestic plants, not enough time to adjust. Also to be expected that new diseases and pests to migrate, against the Germany’s Flora hardly prepared.