Bavarian State Institute of Forestry
Section Biodiversity, Conservation and Hunting
Phone: +49 (8161) / 4591 - 601
Fax: +49 (8161) / 4591 - 900
The wildcat was extinct in Bavaria. Now it is back, especially in the northern part. A monitoring programme based on DNA-analysis provides information on them.
|Fig. 1: More and more often, the wildcat is returning to Bavaria. In northern Bavaria, the monitoring showed the presence of 37 individual wildcats (Picture: Schorle, wikipedia).|
There are two sub-species of wildcat: the European wildcat and the African wildcat. Our European wildcat once occupied large swathes of Europe, but was driven back dramatically over the centuries. The African wildcat is native to northern Africa and Asia Minor, but was brought to central Europe by the Romans; our domestic cats today are descended from them.
Genetically, the two subspecies are clearly distinguishable from one another. Feral domestic cats cannot thus become European wildcats, even when born in the wild. The two subspecies have commonly become known by the names wildcat and house cat, and these are the terms used in this article.
Wildcat and house cat
If a cat is not grey, it is definitely a house cat. The morphological features of cats with the colouring of wildcats, on the other hand, make it very difficult to tell them apart. Wildcats are also very shy animals that are active mainly at night. This means they can often only be observed in conditions of poor visibility and usually only for a short time.
The tails of wildcats are clearly ringed in black and have a non-tapered black tip. House cats do not usually have the dorsal stripe typical of wildcats along their backs. Other distinguishing outer features can only be established in a direct comparison and over longer periods of observation. Dead cats can be distinguished anatomically on the basis of their cranial index and intestinal length.
|Fig. 2: A wildcat rubs itself against the lure-stick, leaving hair caught on it (Picture: A. Bürgel, BUND).|
Since 1992 it has also been possible to distinguish between the two subspecies using DNA analysis. For this you need either flesh or blood from dead animals, or hair from living animals - if possible including the hair roots. This hair is taken from animals caught in live traps or collected from so-called "lure-sticks".
The lures take the form of roughly sawn battens that are stuck into the ground. The above-ground part of the batten (approx. 50 cm long) is sprayed with valerian tincture. The valerian attracts the cats, who then rub themselves on the lure-stick. As they do so, some hair is caught on the roughly hewn batten (Fig. 2). When the sticks are checked, the hair is collected, and the lure-sticks are flamed to decontaminate them, and then re-sprayed with valerian.
Habitat model and home ranges
|Fig. 3: The home range model identifies areas in Bavaria that are suitable as permanent wildcat habitats (already more than 85 % of the forest area).|
In several areas in Germany, the wildcat occurs more often and over more extensive areas than in Bavaria – in the Eifel region, for example. A habitat model has been developed there that is based on the occurrence of the wildcat at a particular location and the habitat features that exist there. This model has been checked in other areas where wildcats occur and is considered to be very accurate.
A habitat analysis has been carried out in Bavaria in order to establish areas that would appeal to wildcats. To this end, the whole of Bavaria was divided into small areas and these were examined for their suitability for wildcats. As the wildcat inhabits living areas of approx. 900 hectares in size, well-suited areas were grouped together with the surrounding forest areas into so-called "home ranges" (Fig. 3). The habitat map for the Jura low mountain range area is still provisional. There would be good habitats there, but water is lacking - the occurrence of the wildcat in the Eifel region is often associated with the presence of water.
Using valerian to find cats - lure-stick monitoring
In surveys carried out on the wildcat, most responses came from the Spessart and Rhön regions, although some isolated responses came from the rest of Bavaria. On the basis of these results, 17 districts in northern and eastern Bavaria were selected, and a systematic lure-stick monitoring programme was implemented there in two consecutive years.
The lure-sticks were only set up in the home ranges identified in the habitat analysis in publicly owned forest, and in the grid already existing for the vegetation survey. Each monitoring point on the grid represents an area of 150 hectares. Assuming each wildcat needs a living area of 900 hectares, every sixth point was established as a searching point.
At each set searching point, three sticks were set up, all 100 m apart in a north-south direction, and the surroundings of the searching point were described. The points were checked six times at weekly intervals during March and April. The hair that was collected was analysed for its genetic content.
Results of the lure-stick monitoring
|Fig. 4: Evidence of wildcats provided by LWF lure-stick monitoring|
Of the total of 1.344 lure-sticks set up at 448 sites, only around 30 % were visited by cats during the two six-week monitoring periods. Of the total of 462 hair samples, only around 10 % were from wildcats. It was very rare for cat hair to be found on all three lure-sticks at any given site. In isolated cases, both wildcats and house cats visited the same lure-stick in different weeks in the sampling period.
As far as possible, the individual animal was identified in the case of the wildcats. This meant it could be established that individual wildcats also visited neighbouring lure sites up to three kilometres away. Two cats were the result of the mating of a wildcat with a house cat. The 37 individual wildcats could be subdivided into 19 males and ten females; in eight cases it was not possible to determine the sex.
When the lure-sticks were set up, the tree species and forest types in the immediate vicinity were also recorded. The lure-sticks were set up in the entire spectrum of forest types, from pure stands (coniferous or deciduous trees) to mixed forest stands. It was possible to detect wildcats across the spectrum. Because of the large size of their home ranges (900 hectares), the wildcat does not have a preference for just one forest type. Their home range is homogeneous only in rare cases. What is most important is that it should offer them cover and a food supply.