Senckenberg Topics

Wolf monitoring at Senckenberg

Interview with Dr. Carsten Nowak


There have been wolves in Germany since they returned twenty years ago. This has led to controversies in politics and in media. Amongst many other institutions, The Senckenberg Society for Nature Research has been chosen as the reference center for wolf and lynx monitoring in Germany and has been investigating all genetic samples from all around the nation in their laboratories since 2010.

Scientist Dr. Casten Nowak spoke with Senckenberg’s online editor Adrian Giacomelli about the procedure for the genetic examinations, hybrids between wolves and dogs, and which rumors about wolves can be scientifically refuted.

How did it come about that Senckenberg performs the national examinations in regard to wolves?   When it became clear that wolf monitoring required genetic follow-up examinations, numerous laboratories in Germany were contacted to inquire about the suitability of the laboratories for wolf and lynx monitoring. We, as the Senckenberg Society for Nature Research, responded and applied. A few months later, the State Conservation Group, a committee of the Conference of Environment Ministers, decided to use Senckenberg as a nationwide reference center. Since the beginning of 2010, Senckenberg has carried out all genetic examinations nationwide, for both, the wolf and the lynx.

That means the federation decided: „Senckenberg should be our laboratory”?
The federal states decided together, based on the proposal of the Federal Agency for Nature Conservation.

How much does Senckenberg earn with the samples?

We charge around 150€ per sample, which includes employee and laboratory costs. Most samples are environmental samples which, like forensic samples, must be examined with great care and caution. Each analysis is repeated several times in order to statistically secure the validity of the results, which greatly increases the effort and costs. In the end, we don’t earn anything from the samples because, as the Senckenberg Society for Nature Research, we are not allowed to earn anything. We’re not a company that has to make sales to make money. We explore nature and do not work for profit. Surplus funds that remain after deduction of personnel and material costs are invested into research, for example to improve methods or to finance doctoral theses that use the data collected for scientific purposes. In the end, through genetic monitoring we learn more about wolves than just their current occurrence and relationships.

How does the sampling work? Suppose a sheep is attacked by a wolf somewhere, do you go there in person and look for traces of DNA there?

No, we don’t take any samples ourselves. The sampling, just like the rest of the monitoring, is the responsibility of the respective authorities of each state. They take the samples and send them to us per mail. Specialized authorities and samplers are trained accordingly.

So, there are many people involved before the sample is sent to Senckenberg?

Examining a kill incident is a relatively complex procedure. First, a person responsible for monitoring must be informed of the incident. Then, a trained person must assess the situation on site as quickly as possible, record everything precisely, take photos and take samples. All of this is then sent to the competent authority, where the case is assessed and a decision is made to send in DNA samples. This is then sent to us by post. At that point, it can have been up to a few days, sometimes even a few weeks.

What happens once the sample reaches Senckenberg?

Once it arrives here, someone takes care of the information and sample management and, if necessary, consults the specialist authority before the sample is examined in the laboratory by a laboratory employee. There, the DNA is isolated and various DNA fragments are read in a chemical solution. The data is then evaluated by another employee who checks the DNA sequences and, if necessary, corrects it. Afterwards, a genetic fingerprint is created for the sample from the repeated results, which is then compared with the DNA profiles from our DNA database. The result is then transmitted to the specialist department, which uses the genetic result and the findings of the cut-log, including photographic cut documentation, to create an overall finding.

How does this genetic test work? What exactly happens and how can you distinguish whether it is a wolf, a dog or a hybrid?

There are different procedures, depending on the question and the suitability of the sample. Wolf monitoring is based on a genetic fingerprint using so-called microsatellite markers. This procedure is also used routinely in humans, for example in forensic medicine. In doing so, several places in the wolf genome are specifically made visible at which different individuals differ from one another. Based on the similarities and differences at these points, kinship relationships are measured and populations of origin are determined. Wolves and dogs can also be separated from each other by this method, whereby caution is advised here. Since dogs genetically represent only one of many wolf populations, one must always pay close attention to which reference material one is testing one’s samples against. If I compare a wolf from Germany with reference samples from domestic dogs and wolves from e.g. Russia, the similarity to both groups will possibly be about as high or low. So, you can easily get supposed hybrids, i.e. mixed breeds of dog and wolf.

Is the distinction between dog and wolf more difficult than would be the case with “normal” species, such as wolf and fox?

That’s right, you need a lot of experience and the appropriate analysis methods. There are now methods that are much more high-resolution and better suited to separating wolves and dogs. In the meantime, more and more complex methods from genome research are used in which large parts of the complete genome are analyzed. With this data as a basis and together with an international consortium, we have identified almost one hundred such locations in the genome at which wolves differ from dogs in general, regardless of their region of origin. We then investigate this if hybridization is suspected. With the help of this marker system, the hybridization up to the third or even fourth generation can be determined.

It is believed that the first wolves coming to Germany were hybrids. Would it have made its way in the genome if the first wolf to cross the border had been a hybrid?

With the methods mentioned, we would recognize if there were offspring of hybrids and wolves in Germany or if the first wolves that once immigrated to Saxony from Poland were already hybrids. Hybridization took place right at the beginning of the repopulation: In Saxony, a she-wolf mated with a German shepherd in 2003, two of the hybrid offspring were caught and placed in an enclosure, and over time all traces of the others were lost. We know for sure that they did not breed. If they did, we might really have a hybridization problem today. Since at that time the population was still very small, every hybridization can affect the entire future population.

Then why do these rumors still exist after they have long been refuted?

This is easy to explain: in some genetic testing methods, the genetic profiles are compared with those of reference populations to identify hybrids. If you take the first animals that were detected in Germany as reference wolf samples and define them as wolves, you might not be able to detect any traces of hybridization with domestic dogs in their offspring. The samples can be clearly identified as the reference “wolves” “assign. In order to avoid possible  distortions of our results, we now rely on modern methods of genome research in which the selection of reference samples no longer plays a role. We know a sufficient number of places in the DNA where wolves and domestic dogs differ from one another regardless of their geographic origin. It doesn’t matter whether the wolves come from
Russia or Germany. We also look at functional characteristics that distinguish wolf and dog, such as the number of copies of the gene that codes for the enzyme amylase. This is used for starch digestion and is available in multiple copies in dogs, but only once in wolves. If the wolves in Germany were hybrids, the population would have to have numerous animals with multiple amylase copies in the genome. However, this is not the case, as studies on hundreds
of wolves in Germany in cooperation with the University of Veterinary Medicine in Vienna have shown.

Wasn’t hybridization also carried out specifically? Weren’t hybrids purposefully bred because they are more dangerous and also have no inhibitions against humans?

People’s fear is deliberately used in order to create a mood against a kind that is undesirable for some. The identical rumors exist in all regions where wolves are spreading again. In fact, experiments were carried out in the city of Perm, Russia, in which wolves were crossed in dog lines. The aim was to create superior working lines for military and police purposes. On the internet one reads again and again that German wolves are descendants of such hybrids. How and why these animals are supposed to have been brought thousands of kilometers to Germany is unfortunately never explained. It is also not about verifiable facts, after all we are all manipulated by chemtrails, etc. So, it’s obvious that our wolves are not really wolves at all. Someone always has spectacular secret knowledge and likes to share it online. The story can be pretty good, too, but unfortunately ultimately fictitious. There is also no evidence at all that wolf-dog hybrids are wilder, more disinhibited and more dangerous than dogs or wolves. Even if the wolves in Germany carried significant amounts of dog DNA, there is a high probability that they would behave like other wolves do. Current behavioral studies on hybrids in Tuscany suggest just that.

Are there any other methods besides genetic testing? So, if the wolf is now suspected of having attacked an animal, are you looking for footprints or something like that?

A seasoned expert can associate a good photo with wolf and dog feel safe. Even first-generation hybrids are often still capable; for longer only modern molecular genetics can help. Even in the case of a torn sheep, access to the causer does not depend solely on genetics. A loss of livestock is seen photographically and in logs on site, and that too is checked with the control of who is actually the cause of the tear. The genetics are of course important, but such a crack assessment is such a process. Like in a criminal case, genetics can refer to another clue, but we at Senckenberg do not convict a wolf or dog, it is dealt with in the responsible government administration of all rights.

What else is actually examined using wolf samples or wolf carcasses that have been involved in an accident?

The wolf samples are scientifically examined very thoroughly by various institutions. When a wolf lies dead on the roadside, it comes to the Leibniz Institute for Zoo and Wildlife Research in Berlin and is carefully examined for the cause of death and the diseases and pathogens present. If possible, the skull comes to Hermann Ansorge at the Senckenberg-Institut in Görlitz for a morphological examination, and of course we in Gelnhausen receive a DNA sample. If feces are found, part of the sample often comes to Görlitz and is examined there for food components. Hair and bone remnants in the excrement are examined to determine whether the wolf has eaten red deer, roe deer, wild boar or farm animals. Therefore, one knows exactly which food spectrum wolves have in Germany. 

Especially on social media, one reads claims again and again that Senckenberg is not neutral in the investigation and cooperates with “wolf-friendly” organizations like NABU. What are you thoughts on these claims?

The Senckenberg Society for Nature Research is an independent institution whose purpose is to conduct nature research. There are no connections whatsoever to nature conservation associations such as NABU with regard to investigations on wolves. The financing of the samples and the commissioning runs exclusively through the responsible state authorities. We don’t examine wolf samples on behalf of nature conservation organizations such as NABU or WWF. We work according to the standards of good scientific practice, as they are generally binding for Senckenberg as a member of the Leibniz Association.