Wednesday 12th June (am)

A twenty minute walk from the hotel and I arrive at the FVA office to meet Dr Micha Herdtfelder. As with all good meetings we start in the kitchen with a cup of coffee, clearly coffee is very important in this office as there is a very swish coffee machine and a coffee machine cleaning rota!

Armed with our coffee’s Micha starts explaining the options for a reintroduction/re-enforcement exercise for lynx in the Black Forest. It’s known that there are approximately 11 male lynx in the area, though it’s unclear how many are resident and how many are travelling regularly between Switzerland (Jura mountains) and the Black Forest. Certainly, the movement is from the Jura mountains into the Black Forest.

Micha explains that a linear regression model was used to model how many lynx could potentially occupy the Black Forest. Data from lynx presence in Switzerland was used together with random points and comparisons were made with known data from lynx in the Black Forest and random points. A number of habitat variables were included in the model for example (not an exhaustive list);

• Topography
• Slope
• Elevation
• Distance to urban areas and infrastructure
• Sex of animal
• Aspect

Calculations, were also made concerning the available prey density within the Black Forest. The resultant Minimum Convex Polygons (MCP’s) differed quite markedly between the known home ranges derived from the Swiss data and the potential home ranges for lynx in the Black Forest.

From what’s understood currently about movement of lynx in the Black Forest (Germany) and Jura Mountains (Switzerland), male lynx are travelling through the Rhine and to the Upper Danube Valley from the Jura. However, females don’t seem to be crossing this area, perhaps due to the presence of substantial infrastructure in one particular part of this corridor.

There are two possible strategies for a lynx re-enforcement exercise in the Black Forest, bearing in mind there are possibly 11 male lynx in the area;

• Release 4 females, monitor what happens, then possibly release another 1-2 females or males.
• Or the optimum scenario, release 8 females and 4 males.

All with the aim of forming a stable meta-population. If this population was unconnected i.e. there was no movement of animals from the Jura mountains, then a similar strategy to that applied in the Rhineland Palatinate would be used i.e. the release of between 20-30 lynx.

Micha, reinforces the message I’ve taken away previously concerning the communication strategy ahead of any release. Micha makes it clear that without the full support of all stakeholders, there will be no re-enforcement exercise within the Black Forest.

Micha and I then spend time discussing good examples of communication strategies that have been used for other reintroduction projects involving large carnivores across Europe, thankfully this information is readily available.

Wednesday 12th June (pm)

After, sharing a lovely lunch with Sabrina Streif we get down to talking wildcats. The recolonisation of wildcats in the Baden-Wuttenburg region was thought to have started 12 years ago. The first two dead wildcats (road kills) were found in the Freiburg area near the border with France in 2006-2007. The lure stick method (previously described) was then used within the Freiburg area to gather more information on the wildcats in this region. One hundred lure sticks were deployed, with 3 sticks per 1km² in an area of wet woodland.

As well as spraying the sticks with valerian, tubes of valerian can be added to the top of the sticks, small holes are drilled into the tube allowing the valerian to be further absorbed into the sticks.

Based on the information generated through the lure sticks, twenty one animals were collared through catching via valerian baited box traps to generate MCP’s, to further understand the ecology of the species, as well as understanding how the animals are dispersing and expanding through the area. The radio telemetry collars (2-5% the weight of the wildcats) aren’t designed to fall off, so the wildcats have to be re-captured to have their collars removed.

Unfortunately, a number of the collars had a high rate of failure due to the dense woodland habitat the wildcats were occupying affecting the signals. Research is currently underway to improve the effectiveness of collars in these habitats. Domestic cats have only been recorded entering this woodland twice in a three year period, which covered 700 trap nights!

Data gathered so far has revealed that wildcats can be found up to 800 metres elevation, it’s uncertain how much higher they will travel.

Wildcats have also been found densely packed into a long strip of broadleaved woodland approximately 500 metres wide, which borders the River Rhine. From here they need to cross through large, open agricultural areas, to reach the Black Forest and it’s here that hybridisation with feral cats can occur. Rates of hybridisation have been recorded at 10% using the single nucleotide polymorphic (SNP) marker method. However, wildcats will use connecting patches/blocks of woodland to move through these areas. Also, largely agricultural land, in the growing season, is less of a barrier to dispersal, as at this time crops are high and cover is dense.

Males appear more willing to cross open agricultural areas, females appear to be largely remaining in the woodland moving a maximum distance of 100 metres from it.

Along with monitoring the wildcats via lure sticks and radio telemetry collars, dead animals provide a further resource. Phenological, anatomical, genetic and pathological information is gathered from dead found wildcats, usually roadkill. Although, phenological and anatomical characteristics would never be used in isolation to identify wildcats, certain characteristics are more indicative of wildcats as opposed to domestic cats. For example, wildcats have shorter intestines due to their carnivorous diet as opposed to domestic cats which are more omnivorous. The pathological information gathered provides data on the ‘usual’ diseases associated with wildcats as opposed to those associated with domestic cats.

A very detailed pathological data sheet exists for dead cat examinations covering the phenological, anatomical, pathological and genetic parameters of which I now have a very handily translated copy.

Thursday 13th June – Wildcat Field Visits

A day out in the field with Sabrina. We drive out to Kaiserstuhl, an area rich in vineyards but which provides another good opportunity to look down upon the areas being used by wildcats. Visit the video page, to view the two video’s taken at Kaiserstuhl.

From our viewing point we look down on an agricultural area with a mix of crops from grapes to wheat, with large blocks of broadleaved woodland throughout, connecting the woodland bordering the Rhine, to the Black Forest in the distance and the French Vosges Mountains. From this vantage point you gain a clear understanding of how the wildcats are travelling through this area including movement through France.

Sabrina and I enjoy lunch by the River Rhine and I find out and am astonished to hear that wildcats have been known to swim across this river when conditions are suitable to use island woodland patches.

We move on to the wet woodland area, where much of the monitoring for the species took place. It’s a mixed woodland but dominated by broadleaved species, largely beech with a dense understorey, with a number of reedbeds, clearings and small streams within it.

Bunkers from WWII can be found in a few areas within the site, which provide good den sites for the females. Monitoring has found that the territory size for both males and females is smaller at this particular site due to the abundance of prey within it. Territories can be 80-300 ha’s for females and 300-1,500 ha’s for males, though it’s difficult to give exact figures.

We discuss development issues which can act as barriers for wildcats and/or increase the risk of fatality. We discuss green bridges, underpasses, barrier fencing, wildlife corridors (as previously described) and Sabrina notes that solar farms, which are largely fenced are creating a new barrier, openings are having to be made to allow wildcats are other species to pass through these areas.

The management of the Rhine floodplain area can also present problems. As the floodplain area starts to flood, wildcats can easily move out of the way either further in land or up into the trees. However, they do so at speed, so local roads have to be closed to prevent fatalities when flooding operations commence.

Finally, we discuss an ‘agri-environment’ type scheme whereby landowners are encouraged to keep old trees and infect them with fungi, specifically truffles. The landowners receive payments for doing this. It takes up to 10 years for the mycorrhizal networks to be established within the trees and during this time wildlife corridors can be maintained or enhanced for wildcats and other species depending on the number of landowners who take up the scheme.

Friday 14th June – Lynx field visits

A day out in the field with Johannes Erretkamps and a switch of focus to lynx. We take a drive out into the Black Forest. First we stop off at the Todtnau Waterfall site to take a view of the area where lynx have been recorded. The area contains a few small villages and farms but is largely dominated by the Black Forest itself.

We drive on to the area where a male lynx is known to reside. He (Wilhelm) was first recorded in the area in 2014, moving into the area from Switzerland and was captured and collared a few miles away in late 2017. However, his collar stopped transmitting only a month later. It’s not known why the collar stopped working, though he is still wearing it.

Through, camera trapping, photographs and information from local hunters a ‘new site’ has been chosen as the area to try to recapture him and fit him with a new collar. This site is the steepest I’ve been in, there are no video’s as I was concentrating on where I was walking and trying to stay upright. It is a mixed woodland, with rocky outcrops, scree and large brash piles, making walking difficult, as felling operations for timber also takes place here.

A box trap is being set in place with a remote triggering device and it’s hoped that Wilhelm will be recaptured soon to enable monitoring to recommence in the area to try to start to rebuild the database for lynx movement in the area.

We then moved on to the area where Wilhelm had been caught originally, quite different from the area I’d just visited but in terms of distance very close, a few miles away. This area, whilst also in a mixed, broadleaved dominated woodland was much flatter, more open and closer to cattle grazed meadows and small villages. Though, it still provided dense cover in terms of vegetation structure together with its rocky outcrops.

And with that my stay with the team at the FVA was over, next stop Bonn and the lynx expert conference.