How to deal with the growing wolf population in Switzerland?

The newspaper NZZ am Sonntag recently published an interview with our in-house predator specialist and movement ecology group leader Gabriele Cozzi about the current wolf situation in Switzerland and the associated research opportunities. The interview was conducted by Atlant Bieri and originally published in german. Below, we provide an english translation.

 

NZZ am Sonntag: Mr Cozzi, this summer a shepherdess and her dog were growled at by a wolf in Graubünden. There have also been more encounters between humans and wolves elsewhere recently. How dangerous is that?

Gabriele Cozzi: In such an encounter, a wolf possibly growls because it is frightened and thus signals its presence. In its language, this means: “Don’t come near me!” If you follow this signal, nothing can happen. In this situation, a wolf would only attack if it feels attacked and sees no escape options. But that hardly ever happens, you almost have to step on its tail.

 

As a defence, the woman called loudly and made herself appear as big as possible. The wolf then left. Does that always work?

She reacted correctly and used the language of the wolf. A loud voice is equivalent to growling. It means: “I am strong and could be a problem for you. You better leave me alone.” The louder you are, the more dangerous you appear to the wolf. For him, this means he could hurt himself unnecessarily if he attacks.

 

Is it also useful to stand up?

Yes, body size is important. In wolf language, it is synonymous with strength. That’s why you should not crouch or bend down to pick up stones as a weapon. It is better to move your hands above your head or to break branches from trees and waving them. But one should not directly attack the wolf. He might think that it is now too late to flee, and he must fight back.

 

Why is running away not a good idea?

It activates a hunting instinct in the wolf: the image of a fleeing prey. This can be observed very well in cats. A mouse dummy that does not move is ignored. Only when you let it slide across the floor does the cat’s hunting instinct kick in and it strikes. It’s the same with wolves. If I run away, I am the prey. In an encounter, the following message must always reach the wolf: a person is something big that is potentially strong and dangerous. Full stop. Then nothing will happen. You can walk slowly backwards, but always keep your eyes on the wolf without staring.

 

Why not?

Staring signals a challenge: whoever averts their gaze first submits. In an encounter, one should neither enter a competition nor be submissive, but rather remain calm and show self-confidence.

 

On another day, the same woman was surprised by three wolves at once. This time the animals attacked the woman’s dog. Why do wolves behave so aggressively towards dogs?

Wolves see dogs as nothing more than another wolf, but a wolf that is degenerate and weak. Moreover, he is an intruder in their territory. That is why dogs rather than their owners are attacked.

 

Sometimes, however, this also means that the dog is killed.

Yes, that can happen. Large predators are not squeamish about direct competition for food. It also happens that wolves kill other wolves. In Africa, lions kill hyenas without eating them afterwards. It is simply a matter of eliminating the competition. Basically, predators don’t like other predators.

 

In August, a group of hikers in Sufers came across two adult wolves that approached within a few metres. Later, the pups also followed the hikers. Why the approach and the subsequent pursuit?

In Africa, zebras are often seen walking directly towards a pride of lions. That means: “I see you and know what you’re doing.” It’s the same with wolves. Especially with parents, they may scout us to find out if we are a danger to the offspring.

With puppies it’s different. For them, everything is a game. They go after anything that moves. I have seen young African wild dogs chasing giraffes. This can be very dangerous for the young dogs, but they need to make experiences to understand it.

 

In North America, the authorities advise hiking tourists to always carry bear spray (pepper spray) with them. Would that also be conceivable in Switzerland?

Absolutely. It works very well in North America. All it takes there is a short blast and the wolf would takes off. Nobody likes to have pepper spray in their face. Using bear spray would only require a small change in our way of thinking. But maybe there is still some resistance at the moment.

 

Wolves seem to appear in settlements for no reason. Why?

You have to distinguish between migrating individuals and resident packs. Migrating individuals travel long distances every day and don’t really know where they are going. They don’t want to go to the city for sure. But in the densely populated landscapes, they only have to turn left once instead of right and they’re already in a village.

Packs, on the other hand, know their territories very well, and if they find something to eat near settlements, they are very likely to come back. This was a problem in Vättis, for example, where the Calanda pack often appeared. There, meat bait had been put out for fox hunting. The wolves quickly learned that they could easily get food here.

 

What does that mean for settlements?

Don’t leave food lying around. This can quickly lead to problems and unwanted encounters. In Turkey, where I researched bears and wolves, there is a town with a big rubbish dump. Bears and wolves come there every night to feed. It’s like a McDonald’s for them.

 

If wolves approach a settlement too often, they are declared problem wolves and can be shot. Would there be an alternative to this?

You can scare the animals away with rubber shot. But such measures, where the animals have to learn something, always take time. It is clear that this method would be very time-consuming for the gamekeepers and therefore not justifiable everywhere. Ultrasound could be used, similar to a cat or marten deterrent. In recent years, attempts have also been made to restrict the movements of predators by placing urine and droppings of conspecifics in strategic locations. We have to learn to be creative here.

 

Farmers in mountain areas have the same problem. They want to keep the wolf out of their pastures. Would there be more possibilities than fences and guard dogs?

We should try to exploit the technological possibilities. GPS transmitters, for example, could help to record the movements and preferred locations of resident packs. In the alpine region, packs have territories of about two hundred square kilometres. But certain locations are only heavily used during certain times of the year, such as the breeding season. The more information we have, the easier it will be to develop preventive measures.

 

There are currently about a hundred wolves in Switzerland, and the population is growing. Will more farm animals be killed every year?

The number of farm animals killed will probably increase. That is pure mathematics. But the number will not necessarily increase linearly: twice as many wolves does not necessarily mean twice as many lost farm animals. This because in Switzerland there are many wild animals such as deer, roe deer, chamois and wild boar, which play a much bigger role as prey than our sheep and goats.

 

But last year even a donkey was killed by wolves. Isn’t the situation deteriorating?

We should not condemn the wolf because of a donkey. At the end of the day, donkeys are part of its possible prey spectrum. It is important to maintain a rational mindset and take decisions based on facts and not emotions. Only in this way will the relationship between humans and wolves be sustainable.

Tracking down an African wild dog den

The winter months of June, July, and August mark the coldest period of the year in Northern Botswana. It is this cool period that African wild dogs choose for whelping, as pup rearing is energetically costly for a pack. Typically, the dominant female looks for a suitable den site, such as an abandoned aardvark hole, where she will give birth. As the mother is obliged to stay at the den to nurse and protect the pups, so the survival of both the mother and pups is fully dependent on the other pack members during this critical period. The rest of the pack all leaves the den site once or twice per day to go hunt, and upon returning, they regurgitate part of their freshly caught meal to feed both mother and pups.

During the denning period, the normal ranging radius of a pack is drastically reduced. Consequently, denning season is the optimal time of the year to locate the study area packs and for pack monitoring. This July we tried our luck to locate the den site of the missing ‘Mula’ pack. This pack was formed in February 2016 by the joining of a male dispersing group with a female group, each of which we had monitored with satellite collars as part of our ongoing research project on African wild dog dispersal. However, these satellite collars both had dropped off by now. As we are also interested in the settlement and reproductive success of recently formed packs, it was critical to catch up with this pack again.

Having no working radio telemetry collars on the pack we were left with no other option than to track down the pack on the ground the old-fashioned way. We already knew that the new Mula pack’s home range extended from Xakanaxa all the way east along the Khwai river to North Gate of Moremi Game Reserve. This meant they could theoretically have been denning anywhere within about 400 km2 and along a stretch of about 50 km. We decided to start our search mission in Xakanaxa where frequent sightings of 12 wild dogs had been reported on the sightings board at Moremi South Gate. The last time we saw ‘Mula’ pack, at the end of 2016, they were ten adults plus two pups. Therefore, these reports sounded promising.

With enough supplies to spend a couple of days away from our research camp, Ed, a Research Technician at Botswana Predator Conservation Trust (BPCT), and I set out for the 50 km drive to Xakanaxa. Upon arrival, we bumped into some safari guides who told us that they had regularly seen a pack of 10 wild dogs and one male was wearing one of our radio collars. Luckily, one of the guides had just seen the pack earlier that morning. Using this information, we started looking for fresh tracks on the main road and soon found some. The prints were following the road for roughly 3km but eventually they left the road and we lost their tracks. We decided to park our LandRover close to a crossroad to see if the pack would use the same road on their way out of the presumed den site for the evening hunt.

Our car parked next to the road in anticipation of the ‘Mula’ pack coming along on their way out of the presumed den site.

Being impatient, we left our lookout before sunset and looped around to the North the nearby Paradise Pools to search there. With no success, we drove back to the crossroad to find out that the pack had just come by, as indicated by the many fresh tracks on the road. We rushed following the tracks and caught up with the pack shortly after. They were spaced apart and due to the progressing darkness, we were not able to count more than eight individuals. As we were taking photos of them for identification, one of the dogs who was lagging behind suddenly turned back and sprinted down the road toward where they just came from. We followed him as we guessed he might have changed his mind and decided to return to the den. He ran down the road at full speed, coming by our stake out place at the crossroad and then continued heading further south. Then suddenly, he turned east into the thick mopane bushes. It was too dark for us to try to follow him through the thick vegetation, we took a GPS fix of where he turned off and went off to find a suitable spot to spend the night. Later that evening we confirmed by examining our photos, that these were indeed the remaining members of ‘Mula’ pack.

Our first encounter of ‘Mula’ pack as they were trotting along to road for an evening hunt.

Early the next morning, we positioned the vehicle again at the crossroad in hopes that the pack would come by again. Unfortunately, no dogs appeared and we had to conclude they must have chosen a different route. Just as we were about to leave, another game drive vehicle pulled up and told us they had just seen the dogs back on the airstrip again heading east – which meant towards where we saw them last night. In anticipation that the dogs would continue running in a straight line, we drove south on the main road and parked close to where the extension of the airstrip would intersect the road. Luckily, we were at the right spot as a group of six of them came out of the thicket and crossed the road. We immediately followed them into the bush. Despite many obstacles, we managed to stick with the dogs for roughly 300m. But then, suddenly, we lost them in a relatively open area. We got out of the car and started looking for fresh tracks. There were quite a few prints on a small game trail. By following them, we ended up in a sandy rift with spaced out apple-leaf trees. Unfortunately, the sand was very deep which made it hard to surely identify any of the many tracks as being from wild dogs.

A subgroup of ‘Mula’ pack crossing the road on their way back to the den site

For the next three days, we continued our search but never managed to close in further to the potential den site. We usually lost track of the dogs in deep sand. As we were running low on supplies, we eventually decided to head back to our research camp. But this didn’t mean that we were giving up. Too close were we in finding the den site to call our mission a failure.

One of the identification photos we took of the ‘Mula’ pack dogs after we bumped into them early one morning.

A few days later we drove back to Xakanaxa early in the morning accompanied by ‘Tico’ McNutt, founder and director of BPCT, who has decades of experience in tracking wild dogs. He seemed quite confident in finding their den based on our preliminary efforts in narrowing down the search area. As we approached Xakanaxa, we drove to the spot where Ed and I lost sight of ‘Mula’ pack previously. Tico got out of the car with Ed and me following. He first circled around the spot in a wide loop in search of any fresh tracks. Once we closed the loop he headed for the direction where he must have seen the most promising tracks. Shortly after, he showed us fresh dog tracks and pointed towards the direction they were leading. After about 1.5 km we approached an open sand ridge. Tico told us to stick close together as he was confident of the den being nearby. We followed the fresh tracks in deep sand, and as we were approaching a few apple-leaf trees we suddenly heard the alarm bark of a wild dog. This was undoubtedly the den site we had been looking for. We crouched down but weren’t able to get a visual of the dog as the trees were quite dense. We decided to take a GPS fix and return with the vehicle.

Impressed by the way Tico tracked down the den in no time, we started heading back. After a few steps, he stopped and showed us animal tracks in deep sand. What seemed like it could have been any track to Ed and me, was definitely the spoor of a wild dog according to Tico. He pointed out that he could detect wild dogs in deep sand based on their gait. Two feet are always placed close together with a bigger gap between the next set of pads whereas the step lengths of hyena prints are generally more regularly spaced. This was an important lesson for us and definitely made the difference as Ed and I were constantly losing the dogs in soft substrate during our previous search efforts.

Wild dog tracks (left) are not always as distinguishable from hyena tracks (right). As the substrate gets softer, details of the paw vanish quickly. We learned from ‘Tico’ that it comes down to look for gait patterns such as spacing between the footprints in deep sand.

On our drive to the newly-discovered den site we were not able to see more than half a dozen of the adult dogs nor to get a visual of any pups. But when Ed and I drove back to the den a few days later, we managed to identify all ten adults, the two yearlings, and watch twelve new-born pups play youthfully outside the den. It was well worth the effort:  No dogs had died since our last detailed encounter with the pack seven months ago and a promising number of pups was about to grow up.


Watch the ‘Mula’ pups as they emerge from the den:

 

Find out more about this project by visiting our research page:
African wild dog dispersal and demography

Where can the wild things roam? Combining ecological suitability and human acceptance for the Swiss wolf.

About one third of the Swiss landscape offers suitable wolf habitat. Nonetheless, there is only a small fraction thereof where the wolf is tolerated by local communities. Those regions – characterized by both favourable environmental conditions and a positive attitude towards the wolf – are identified as candidate regions for the successful short to medium-term wolf expansion, according to a study conducted by the population ecology research group at the University of Zurich

©RamiroMarquezPhotos / iStock

The wolf was eradicated in Switzerland and from large parts of continental Europe including France and Germany by the end of the 19th century. Following legal protection, the wolf population started naturally increasing and expanding, and in 1995 its presence was confirmed in Switzerland. Sightings have increased since. Despite 13’800 km2 of Switzerland are characterized by favourable conditions such as large forests with little human pressure and have thus been identified as suitable wolf habitat, wolf expansion in Switzerland has been substantially slower than in other parts of continental Europe. As the wolf is more and more subject to human-dominated landscapes, scientist at the University of Zurich developed a novel method that integrated both ecological and human components to identify regions with favourable environmental conditions and where the wolf was tolerated.

Mapping human acceptance of the wolf to identify suitable socio-ecological areas

socio-ecological suitability model
Combining human acceptance (a, c) and habitat suitability (b, d)
helps identifying socio-ecologically suitable wolf habitats in Switzerland (e).

About one third of 10,000 randomly selected residents in Switzerland participated in the survey. Combining the response from questionnaires with geographical information, Dominik Behr and his team created a nationwide map of human acceptance. Acceptance decreased with increasing altitude of residency and even more so where high numbers of sheep and goats were held. Acceptance increased with increasing distance from confirmed wolf presence and in densely populated areas. People who perceived the wolf as dangerous to humans and harmful to livestock and wildlife mainly opposed the wolf. Younger people, and people who believe that the wolf had a positive influence on the ecosystem had a more positive attitude towards the predator.

“When we overlapped our human acceptance map with a habitat suitability map for the wolf, we realized that only about 6% of Switzerland was characterized by both a positive attitude and favourable environment conditions. This was in contrast to results from the habitat suitability map, which returned one third of the Swiss landscape as being suitable for the wolf” said Dominik Behr. “As wildlife biologists, we are good at understanding the ecological factors determining the suitability of a habitat for a wildlife species. Due to ever-increasing overlap between human and wildlife, however, we are obliged to take into consideration how human acceptance modifies our ecological description of habitat suitability. This study demonstrates one effective way to do this.” stressed Arpat Ozgul, professor of population ecology at the Department of Evolutionary Biology and Environmental Studies at the University of Zurich, and co-author of the study.

A novel framework to manage wolves and people
The socio-ecological map created by Dominik Behr and his co-authors appears to accurately represent the wolf situation in Switzerland of the past years, including identifications of areas of high, moderate or limited conflict. “By capturing areas characterized by both favourable environmental conditions and a positive acceptance towards the wolf, our approach is a valuable tool to identify overall socio-ecological suitable areas for the wolf. Under given conditions, those regions are good candidates for the successful short to medium-term expansion of the wolf. Additionally, this approach allows to identify key regions where proactive and targeted socio-ecological management plans and a constructive dialog among different stakeholders are needed” said Dr. Gabriele Cozzi, who coordinated the study.

Special thanks go to the 3142 people that returned the completed questionnaire – this study would not have been possible without their contribution.

Behr DM, Ozgul A, Cozzi G (2017) Combining human attitude and habitat suitability: a unified socio-ecological suitability model for the wolf in Switzerland. Journal of Applied Ecology

Popecol group started to form postwomen and postmen

Do Swiss people support or oppose wild living wolves in Switzerland? Do wolves encounter a positive “human environment” in areas with suitable habitat conditions? To answer these questions, Gabriele and I are conducting a mail survey among a random sample of the Swiss population. In order to master the logistics of mailing out 10’000 questionnaires, the Popecol group jumped in with many supporting hands.

Questionnaire about people's attitude towards the wolf in Switzerland
Questionnaire about people’s attitude towards the wolf in Switzerland

A questionnaire with sections on attitude, perception and knowledge of the wolf, experience with the wolf and personal information about the respondent was developed and translated into German, French and Italian. Before going big and mailing out 10’000 questionnaires, a pre-study with 200 randomly chosen people was conducted. So far the pre-study yielded a return rate of almost 30%, which is higher than expected. With this first promising outcome in mind the time was ripe for undertaking the logistics of printing, folding and packing 10’000 questionnaires.

With great support of the Popecol group, the first packing round successfully went off without a hitch. In groups of two helpers, the questionnaires were packed in envelopes together with a cover letter and a return envelope. So far, the first 4’000 questionnaires are on the way to be delivered to the randomly chosen respondents all over Switzerland. The last packing round is scheduled and the remaining questionnaires are planned to be sent out soon.

Envelope packing procedure performed by the Population Ecology group
Envelope packing procedure performed by the Population Ecology group

Thanks again for the great support and let’s keep our fingers crossed for a high return rate!