The biologist Bernhard Kegel shows us drastically the consequences of our way of life: Man-made climate change and the exploitation of the environment are forcing animals and plants to adapt – but does that save them from extinction?
Mr Kegel, in Chukotka, on the northeast coast of Siberia, a dramatic animal death is taking place, which can be attributed to climate change. It affects the walruses, each weighing up to a ton, impressive animals that still exist there in a population of up to 100,000 specimens.
Yes, a film team documented these processes during an expedition on the edge of the Chukchi Sea. The walruses lived for thousands of years on the large ice sheets on the sea. But they are disappearing more and more due to climate change. The result: The animals now huddle very closely together on a narrow strip of coast. Since they have less and less space there, hundreds of them heave up the approximately 80-meter-high cliffs, rest there and then rush over the slopes into the depths. They injure themselves badly and die. The animals see very poorly, but they smell the sea and then choose the direct route there without understanding that it means death. These are very moving images that made the research team cry.
It is a drastic example of what climate change is doing for animals on earth.
With the warming of the earth, the areas of distribution of animals and plants are changing rapidly. They move towards the poles, in the northern hemisphere towards the north pole, in the southern hemisphere towards the south pole. In the mountains, the species move up to the cooler, in the seas they try to reach cooler water layers. This is a natural evasive movement in order to continue to live in the preferred temperature range. That was also the case during other warm phases in the earth’s history. Problems arise because such movements are only possible to a limited extent today, because we humans are increasingly narrowing the spaces for animals and plants through our way of life. Through huge agricultural monocultures that are treated with pesticides, we have created no-go areas for insects. The cities have taken on enormous proportions and set tight limits to the animals and plants. The sixth mass extinction of animals and plants in the history of the earth is underway and it has nothing to do with climate change. Up to 50,000 animal species are lost every year. In addition to this development, there is also climate change.
How do the animals and plants try to adapt to the warming?
The plants climb up mountains first, followed by the animal species that depend on them, such as butterflies and other insects. In Switzerland it has been proven that this upward movement now amounts to several hundred meters. When it comes to birds, the short-migrants who do not have that far to winter quarters return earlier from there to Central Europe. Long-distance migrants like the cuckoo get big problems. He has to find more and more that he is too late to lay his eggs in other birds’ nests because they breed earlier because of the warming. Cuckoos that specialize in resident birds or short migrants as hosts will probably become extinct.
In the seas, ever larger warm water areas, so-called blobs, are observed, in which the temperatures are two to three degrees higher than usual. What are the consequences for the flora and fauna?
Indeed, marine heat waves are increasing in frequency and severity. In the North Pacific one reached enormous proportions in 2015/2016 and was christened “Blob”. In large areas, the water temperatures rose by around 2.5 degrees. As a result, this led to dramatic animal deaths. The mass of plankton decreased, so there was less food for fish, and seabirds starved to death. Large marine mammals such as whales were far less able to raise young animals.
An animal that is very popular with many people, the polar bear, has major problems due to the decreasing ice surface around the poles.
In the Arctic, the areas covered by ice are rapidly decreasing. This is not only a problem for the walruses, it is now becoming very difficult for polar bears too. When there is no more ice, the bears are forced ashore. There are increasing conflicts with people and human settlements. But don’t forget: the polar bear is one of the most dangerous animal species in the world. On land he now increasingly encounters other bear species such as the grizzlies. There are crossbreeds that we call “cappuccino bears” with light brown spotted fur. The polar bear threatens to disappear little by little and to merge with the brown bears. The entire ecosystem in the Arctic, but also in the Antarctic, is currently changing dramatically.
However, it seems to me that for many people in Europe these changes are literally still a long way off.
To person
“The nature of the future” is the title of the current book by biologist Bernhard Kegel, published by DuMont. In it, he describes how animals and plants are fighting against climate change and what strategies they are developing for survival.
Bernhard Kegel, born in Berlin in 1953, studied chemistry and biology and worked as a researcher, ecological expert and lecturer. He has been publishing novels and non-fiction since the early 1990s, and in 2018 his book “Extinct to Stay” about dinosaurs and their descendants was published.
Well, of course there are already strong ecological changes in our latitudes. But we still live in Central Europe on an island of the blessed. The problems are much more noticeable at the poles and in the tropics. In the already hot areas, animal species are quickly overwhelmed by even slight increases in temperature. The animals collapse. For example, bats like the flying foxes died by the thousands from heat waves in Australia. They have been pushed out of their old habitats and now live in the parks of big cities like Sidney and Melbourne, which are heating up even more. There death now takes place in front of the people.
Large coral reefs are critically endangered off the coast of Australia. Can the corals help themselves?
Corals are the best engineers of large ecosystems. They form huge structures. Up to 800,000 animal species depend on large coral reefs. More and more corals suffer from coral bleaching due to the warming of the water, which means that they repel their symbiotic algae and what remains is the bare limestone skeleton. But there is a glimmer of hope. Because it shows: bleaching is reversible. The corals are able to accept new symbionts and recover. People can support this by training the algae cells to have a higher heat tolerance beforehand. Coral species have also been found in the Red Sea that hardly seem to mind the heat. In the history of the earth there have been phases in which corals seem to have completely disappeared. But they always survived somewhere and then reappeared. However, it took millions of years.
In your book you are not completely pessimistic about the consequences of climate change and extinction for animals and plants. What will nature look like in the future?
The nature that is familiar to us will no longer exist in this way. Nature will stay, but it will change. How much depends on the degree of warming. The migratory movements that we are now experiencing in animals and plants are nothing more than an attempt to survive. We should therefore not fight these migrations in principle. That would be wrong. It is right to fight dangerous immigrants, such as the tiger mosquito, because it transmits diseases. But when new species of dragonflies and birds appear as immigrants, we should greet them and make it easier for them to immigrate.
How can we support the positive migration of plants and animals?
We need green corridors so that species can migrate. In individual cases we should think about relocating animals and plants. There is, for example, a proposal to establish the extremely rare Spanish Imperial Eagle in Great Britain. The same goes for the Iberian lynx.
So, as a result of climate change, we have to get used to new animals and plants in our latitudes, i.e. in Central Europe?
Yes. I even assume that in the next 20 to 40 years the biodiversity in Central Europe will increase rather than decrease. But this will only be temporary. In the long term, we are threatened with a drastic impoverishment of nature. That depends very much on human behavior and our ability to stop man-made climate change. Climate change has occurred time and again in the history of the earth. But what we are currently experiencing has never happened before.
What makes this climate change so special and so dangerous?
Its speed. Such a pace of change has never been seen before. We must therefore under no circumstances let up in our activities to limit climate change. Otherwise, there is a risk of a dramatic decline in biodiversity on earth in the long term. But we absolutely have to preserve biodiversity. Diversity is a guarantee of survival for the ecosystem, and therefore also for ourselves.
Interview: Claus-Jürgen Göpfert
