The fire salamander has a problem – that’s one of the reasons why it was proclaimed “Cave Animal 2023”. A conversation with the researcher Stefan Zaenker about subterranean biotopes and the disruptive factor humans
Mr. Zaenker, as a speleologist you are often underground – which animals do you encounter on your forays?
There are quite a few. In Germany we have a total of 750 species of cave animals, which can be divided into three groups: on the one hand, animals that spend the winter or summer, including bats. They have to rely on burrows in winter. Then there are animals that live in caves all year round and form fixed populations there, but can also do so outside on the earth’s surface. These include various millipede, isopod and spider species. And there are the “real” cave animals, of which there are 150 different species in Germany, which can only live underground. They are mostly white, have elongated limbs and are blind. A representative of this group is the cave amphipod Niphargus, which was the first cave animal of the year in 2009.
How often do you encounter fire salamanders?
Very common as larvae in water bodies in summer. The females often go specifically into subterranean waters and lay their larvae. Adult fire salamanders are mainly found during the winter, they are mostly outside in summer. In winter, caves are a good refuge, since there are many other animals there, they always find food. You don’t have to hibernate for the winter either. We see them quite often during bat checks.
Now the fire salamander is cave animal of the year. This appointment is usually made to draw attention to endangered animals. Why the fire salamander?
There is a huge problem with the fire salamander: the so-called salamander eater. It’s a fungus – no one knows exactly how it got introduced. In any case, he eats the fire salamanders alive, so the animals die from the fungal disease. In the Netherlands, this has meant that the fire salamander has all but gone extinct there within a few years. This fungus keeps migrating east. It has not yet arrived in Hesse, but there are finds in the Eifel, where many salamanders die, and individual finds in the Steigerwald and on the Swabian Jura. We fear it will spread further. You can really understand how he’s getting closer and closer over the past few years. The fungus completely wipes out the populations.
What can you do about it?
You could only do something about the fungus by badly affecting the environment around it. Of course there are fungus remedies, but the problem is that the fungus not only affects salamanders, but also newts, but they don’t necessarily die from it. However, if you have an area where fire salamanders and newts live, then it is difficult to control the fungus. We speleologists have made it our task to at least be careful not to carry the fungus from one quarter to another.
How do you prevent this?
When I’m in a cave in the Rhön and I know I’m going to a cave in northern Hesse next weekend, I meticulously clean my equipment and clothes. There are also different action templates, for example that things should be treated with antifungal agents. I don’t find that very exciting, because if I carry the antifungal agents into a cave in which there are very rare creatures and populations and the antifungal agents then get into the cave or into the water, then they kill other animal species. There are many amphibian conservationists who say, “You have to clean everything with antifungal agents,” but there are more animals than the fire salamander.
A dilemma.
Of course I also think it’s sad when it dies out, but we won’t be able to prevent it like this. Who prevents a timber truck from Holland that collects wood from driving into the forest with tires that are not treated with antifungal agents? Or that a hiker hikes in the Eifel and the following weekend in the Rhön.
How threatened do you think the fire salamander is?
Very, very threatened. We see that where this fungus occurs. Within a few years, the entire populations there are wiped out. Everything must be done to prevent further spread. Speleologists also have to participate in this. That’s why we chose the fire salamander as cave animal of the year. So that we can also make it known to us: There is this mushroom. Wash your clothes properly and be careful! And so that you don’t go to every quarter where you know there are fire salamanders.
With your work, you not only want to sensitize people who are out and about in nature. They also repeatedly appeal to politicians. What about the financial means for researching the ecosystems?
to the person and to the animal
Stefan Zaenker, 57, is a biospeleologist and works for the Upper Nature Conservation Authority at the Kassel Regional Council, where he is responsible for caves, bats and springs. For 40 years he has been caving and dealing with the wildlife found there. He is a speaker at the Association of German Cave and Karst Researchers and heads the Cave Animal of the Year project. In 2020 he published the book “Die Höhlentiere Deutschlands. Find – Recognize – Determine”.
The Association of German Cave and Karst Researchers has named the fire salamander cave animal of the year 2023. The species was first scientifically described in 1758 by the naturalist Carl von Linné. According to the association, the fire salamander (Salamandra salamandra) has been probable for several years by the
The skin fungus Batrachochytrium salamandrivorans (Bsal for short, also called salamander eater or salamander plague) introduced from East Asia is under serious threat.
Fire salamanders can be found in large parts of southern and central Europe. The animals are often described as poisonous because they can secrete a secretion that is primarily intended to protect them from predators. In humans it causes – normally – at most a slight burning sensation, but you shouldn’t touch it. FR
A lot of things are only done on a voluntary basis, including what we do at the Association of German Cave and Karst Researchers. We did, however, receive recognition in May. We had developed a program with the Hessian State Association for Cave and Karst Research to assess caves and record animals – with an app called CaveLife. We have thus won the highest European nature conservation prize, the “European Natura 2000 Award”. This is also entirely voluntary.
What is this app?
This allows a cave and its complete inventory to be evaluated: what are the structures like stalactites or shafts; which animals are there and are there any impairments such as garbage or geocaches. The app is also used by speleologists in other European countries.
Since you mention geocaches, are those “treasure boxes” found using GPS data a problem?
Yes. Especially in winter. When bats hibernate in open caves and there are geocaches in them. Then the bats are disturbed, each awakening consumes energy – if the animals wake up five times, they will not survive the winter. And I’ve seen journals for geocaches in bat caves, 150 people registered in December alone. They don’t even notice that they’re breaking something. You don’t have to go to the bats’ winter quarters for this. Caves have been specially protected biotopes under the Federal Nature Conservation Act since 2019, and there is also a ban on entry.
Back to the fire salamander: I’m just assuming that many people only know that the animals are colorful and learned as children: Be careful, they are poisonous! Are they really?
They already have a poison in their skin, and you shouldn’t touch amphibians anyway. But even if you touch one, it’s enough to wash your hands well afterwards. You don’t have to lick them or rub your eyes. I know of a ranger whose dog ate a fire salamander and died from it. But why would a human eat a fire salamander? Apart from that, it mainly damages the skin of the animals when you touch them.
As the?
We have bacteria on our skin, among other things, and they spread to the fire salamander, which can cause diseases. It harms people less than animals. You shouldn’t touch frogs either.
By choosing the cave animal, you also want to point out that there is an enormous need for action when researching subterranean ecosystems and the species that occur in them. What is it about?
Hardly anyone knows anything about cave animals. This is a living space that hardly anyone gets into. You need the right equipment and you can’t be afraid of narrow spaces or dirt. Even authorities know little. A lower nature conservation authority in North Rhine-Westphalia recently claimed that there are no cave animals in NRW. And if so, then you would know about it. This is of course complete nonsense! The need for action is definitely there. We’re seeing that in the authorities right now.
What are they doing? Or rather, what are they not doing?
Caves are simply dismantled, in quarries or during construction work for road or railway construction, and no one even checks beforehand whether there are any rare animals living in them. Concrete is simply poured in. And then there are animal species whose habitat is limited to individual caves. In northern Hesse we have a cave with a lake – and in this lake there is a very rare freshwater polyp. This is an animal that sits firmly on a tree and catches cave crabs with its tentacles. This is the only known locality in the world. Imagine someone throwing batteries or rubbish into the lake, if only out of inattention. Then the animal is dead – and nobody noticed.
Interview: Andreas Sieler
The fire salamander has a problem – that’s one of the reasons why it was proclaimed “Cave Animal 2023”. A conversation with the researcher Stefan Zaenker about subterranean biotopes and the disruptive factor humans
