Although the cause, climate change, is man-made, the spread of the bee-eater is entirely natural. It’s very different in the case of the raccoon and the tanuki, or Japanese racoon dog. After escaping from fur farms, these species are spreading at an incredible rate in Central Europe, including in Bonn. "I first saw one racoon in Bonn 20 years ago. Now they are constantly fighting with my cats in the garden," says Alexander Heyd, of the German Nature and Biodiversity Conservation Union (Nabu).

The big problem with raccoons is that they are incredibly smart and very skilled with their hands. "The raccoon eats everything that comes under its nose, including amphibians. This is an ecological disaster." Heyd says that getting a grip on the raccoon is wishful thinking: 10,000 are caught every year, but this barely stops them spreading.

And there are climate change losers. Talk to Alexander Heyd, and it doesn’t take long to see that he is fascinated by the topic of biodiversity in Bonn. He is especially interested in the fate of one grasshopper. "In the 1990s, the variegated grasshopper was an ordinary species, commonly found here in the region," reports Heyd, an honorary board member of Nabu Bonn. Since it is very sensitive to drought, it took only a few years before the species disappeared from in and around Bonn. "Unfortunately, no one notices that the variegated grasshopper is extinct here because no one really cares," Heyd laments.

While Heyd says grasshoppers are the best indicators of climate change, they are not the only example. "The animal world in Bonn is permanently changing". There are manifold causes. Climate change very often plays a role - as it did for the variegated grasshopper - but not always. The nutrias, which everybody knows in Bonn, escaped from a fur farm and are multiplying. That said, not all species are invasive, meaning that the spread of some species does not negatively impact the local ecology. While some species become extinct in the region, newly arriving ones in turn enrich biodiversity.

The bird world is also affected by climate change, Darius Stiels reports. On the one hand, the arrival and breeding periods of many species are changing, on the other hand, some species are becoming extinct in and around Bonn. Others, like the grey heron, now remain in the Rhineland for the entire winter. Stiels says the reasons are obvious: "We now have milder springs and shorter winters in Central Europe."

One bird being affected by temporal shifts in the region is the cuckoo. Cuckoos lay their eggs in nests built by other birds, and they let these so-called host birds hatch them. But many host birds are now hatching their eggs earlier because of the mild winter. "And no one tells that to the cuckoo, which winters south of the Sahara," Alexander Heyd explains. If the cuckoo can’t find a nest with unhatched eggs at the end of April, then it’s in trouble. The bird's strategy of laying its eggs in a nest made by another bird could become its undoing and lead to the extinction of the bird in and around Bonn.

Another problem is that the drier and warmer summers are causing wetlands to dry out earlier and faster, says Christian Chmela of the Bonn/Rhine-Sieg Biological Station. "We are noticing more and more that species that depend on such wetlands are disappearing," he says. This is not only bad for vegetation, but also butterflies such as the Dark Marsh Blue, he adds. Only the wetland meadow "Pützchens Wiese" still has this rare butterfly species. The conditions at Pützchens Wiese were designed to be as optimal as possible. "But despite good management, at some point there's nothing more you can do, and you have to watch a rare species disappear from the Bonn region." Original text: Jasper Nebel Translation: Jean Lennox