Wetenschap - 11 oktober 2012

Who's afraid of the big bad wolf?

Farmers fear its arrival. Members of the public are wary of it. And nature lovers cannot wait for the day the wolf finally moves into Dutch territory.

One way or the other, the wolf appeals to everyone's imagination. At the government's request, Alterra researchers are setting the record straight on a number of points. Ten questions and answers on Canis lupus.
Are they coming or are they not?
A definite 'yes' from Geert Groot Bruinderink, author of The arrival of the wolf (Canis Lupus) in the Netherlands. 'If the current trend continues, it is very likely that the wolf will turn up in the Netherlands.' The trend he refers to is the speed at which the wolf has moved towards the Netherlands from eastern Germany since 2000. The estimated 11 packs of German wolves (100 individual animals) originally lived in the Lausitz region of the German states of Saxony and Brandenburg. This is a little less than 600 kilometres from the Dutch border. Meanwhile, the wolves have advanced to about 300 kilometres away - a distance that is peanuts to a wolf. Young wolves in search of new territory can easily cover hundreds of kilometres, unimpeded by obstacles such as highways. So the experts think the wolf will certainly reach the Netherlands. The real question is whether it will stay. 
Will the wolf be a long-term resident?
Opinions differ on this one. According to Groot Bruinderink, the chances of the wolf staying long are small. To establish a pack you need a male and a female, and they need to survive long enough to reproduce. Groot Bruinderink does not think they will easily manage that in the Netherlands, which is simply too crowded. The only areas where the wolf would stand any chance of establishing itself would be the border areas of Groningen, Drenthe and Limburg. Meanwhile, model calculations done by MSc student Astrid Potiek under the supervision of Wieger Wamelink and Frank Langevelde suggest that the wolf may well come to stay. 
How many wolves can the Netherlands cope with?
That depends how you look at it. A pack of seven wolves needs a minimum continuous territory of 125 square kilometres. On this basis, Alterra's study (Potential for Grey Wolves in the Netherlands) suggests that the country could host as many as 300 wolves. And that is not without taking the wildlife crossings into account. 'If you include those - the 20 that are already established and the 20 that are planned - then you arrive at 450 wolves,' says researcher Wieger Wamelink. 'But in practice there will never be that many,' he adds reassuringly. Using population dynamics models we end up with a stable figure of 50 wolves.' However, Wamelink's colleague Groot Bruinderink does not set much store by these kinds of calculation. 'I wouldn't risk any firm statements about numbers at all. It depends on too many variables, and these sorts of models are hardly applicable at all in practice. Let the wolf decide. And I wouldn't think in terms of numbers of wolves but in packs, for example one in the north, one on the Veluwe and one in Limburg.' 
Is the wolf dangerous?
The chances of you or me coming face to face with a wolf, once they are in the country, are practically nil. Wolves are very shy creatures, and it is important that they stay that way, according to Groot Bruinderink. 'Above all, you mustn't give them the chance to lose their shyness. You see that happening with the wild boar on the Veluwe. They are getting used to human behaviour and are becoming less timid. And then things can get dangerous. We call this habituation. People and wolves must stay out of each other's way.' 
How do you recognize a wolf if you do meet one?
Wolves look like large dogs, although their bodies and legs are longer and their heads are bigger. Their foreheads are broader and their ears are relatively short. And their eyes are slightly slanted. Yet the experts say it is really difficult to distinguish a wolf from a large dog. There have been several reported sightings of wolves in the Netherlands in recent years. The last one came from Wageningen doctoral researcher Lennart Suselbeek, who thought he saw two wolves in the forest between Ede and Wolf(!)heze last December. Evidence is lacking though. 
Are we afraid of the (big bad) wolf?
The wolf gets a bad press in many a fairy tale. But who believes in fairy tales? The last wolf was spotted in the country in Limburg in 1897. And we are no longer so afraid of wolves, according to a study by Intomart. Almost half the Dutch (45 percent) say the wolf is welcome. One quarter are neutral on the matter and one third are against an influx of wolves. Most people would like to see a wolf in the wild and only one third find the idea (very) scary. So the Red Riding Hood syndrome does not seem too much of a problem. 
What do wolves eat?
The first wolves in the country will mainly target sheep. 'Easy food,' says Groot Bruinderink. 'The pioneers of a new population mainly target easy prey. Anywhere where new predators turn up they seem to be very interested in sheep at first. Only later do they transfer their interest to hoofed animals such as deer and wild boar.' And wolves are very pragmatic creatures who will adapt their menu to what is on offer. 
How much do wolves eat in fact?
An adult wolf eats 35 to 45 deer per year and 50 to 80 wild boars. Obelix cannot compete with that. But our Dutch countryside can easily absorb that level of consumption. Based on the rule of thumb of one wolf per 100 hoofed animals, Groot Bruinderink thinks the Veluwe could host 120 wolves. So food is not the limiting factor.
How should we prepare for the wolf's arrival?
Groot Bruinderink has advised the Dutch parliament that the wolf should be placed on the list of protected species. There is also a need for a wolf plan making arrangements for such things as compensation for damage, gathering expertise and keeping the public informed. The first wolf to establish itself in the country will be fitted with a transmitter so that scientists can closely monitor where it hangs out. Openness is crucial, says Groot Bruinderink. For this reason he would like to see a wolf ombudsman, an independent oracle on all matters concerning wolves. 
Will the Dutch countryside benefit from the presence of wolves?
'Something that is missing in the Netherlands is a top predator,' says Wamelink. 'The wolf could provide one. I think nature will then start to develop in new ways. For example, the large grazers start to behave quite differently when there are wolves around. Wild boar and deer will not so readily show up in open spaces and their grazing patterns will change. This will lead to greater variation in the vegetation. The wolf could help create a new ecological balance. I therefore see the wolf more as an opportunity than as a problem.'  It will make things a lot more exciting, predicts Groot Bruinderink. 'Of course the arrival of the wolf would be the crowning achievement of nature conservation. It would make the ecosystem more complete.' But you cannot call it a natural balance, in his view.  After all, humans decide to what extent they want to live side by side with the wolf. 'It will always be a derivative of a natural balance. It is more of a social balance.'

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