Wetenschap - 23 september 2010

Dutch farmers on wild goose chase

The Netherlands has the biggest wild goose population of any country in Europe. The problem is that hosting geese in such numbers costs the country a small fortune. The Agricultural economics institute LEI has done the sums on how it can be done more cheaply. But geese expert David Kleijn of sister-institute Alterra does not agree with the findings. ‘Tackling the symptoms’, he calls the LEI’s recommendations.

'You can set your clock by them. At seven thirty in the morning there come the grey geese and the white-fronted geese. And at five thirty in the evening off they go again. It's an invasion. My wife has filmed it. The sky goes black. There are thousands of them.' Livestock farmer Frans Rigter is a calm fifty-something who looks as if he wouldn't say boo to a goose. Not so, it seems: 'this drives me crazy', he says.
Rigter has a farm (80 cows, 80 sheep) in the Maat polder near Eemdijk in the province of Utrecht. His 35 hectares of land are squeezed in between the Eeemmeer (a lake) and a 200 hectare Natuurmonumenten nature reserve. Admittedly, you couldn't find a worse spot for geese problems. 'This is the perfect life for those geese. There is no hunting in the reserve, and the water level is high. And they can find sheltered places to sleep at the Eemmeer.'
Crossing the boundaries
The Netherlands is an Eldorado for overwintering geese. There is food in abundance: juicy grass, the gleanings in the harvested fields, winter wheat. And everywhere there are lakes, ponds and open water where they can sleep in safety. A land of plenty. But farmers are left with the damage done by the birds. To get things under control, foraging areas were established five years ago: farmland on which geese could settle undisturbed - in return for financial compensation.
But on the ground things are not so easily managed. The geese ignore their expensive foraging grounds and no amount of targeted hunting and chasing them off has helped: these geese are stubborn, smart and are staying longer and longer. With soaring costs for hosting the geese and compensating farmers as a result.
Taking the law into his own hands
If nothing is done, in four years' time geese are going to cost the government 29 million euros per year. That is sixty percent more than two years ago and almost four times as much as they cost before the introduction of the foraging areas. The ministry of Agriculture, Nature and Food Quality (LNV) asked the LEI (part of Wageningen UR) to calculate the costs of several alternatives (see box). Stopping compensation payments for damage outside the foraging areas is one of the options that could cut costs.
Not a good idea, says geese researcher David Kleijn from Wageningen UR's green institute, Alterra. 'You can't defend a step like that. A farmer whose land happens to lie outside such an area has to take expensive measures to get rid of the geese, while his neighbour within the area gets compensation for such expenses.' The principle of protected areas is that you teach the geese where they are allowed to graze and where they are not, explains Kleijn. But that only works up to a point. 'One of the reasons is that the goose always weighs up how much food is available in an area against the risks there. So you have to ask yourself how much effort will have to go into scaring the geese away from particular areas.'
'In that case I'll make sure they don't come here any more', farmer Rigter responds with feeling. 'They attack your livelihood. I will do anything I can to get rid of them. If necessary, I will poison them, but I am not allowed to say that, I suppose.' He explains his strong reaction. 'They eat your most valuable grass, the spring silage. They also trample all over your land with their big webbed feet, and you don't get any compensation for the damage they do. And you get all their droppings as a free gift. That manure gets into your silage and you don't know what kinds of diseases come with it.'
Shooting is pointless
Another option for cutting costs is active population management, says the LEI. In other words, shooting more geese. But Kleijn does not believe that is effective either. He calculates that you would have to shoot between 150,000 and 300,000 white-fronted geese alone to reduce the population by thirty percent. Add to that about 35,000 to 70,000 grey geese.
In any case, large-scale culling would only help in the short term, according to Kleijn. 'If you shoot, say, twenty percent of the animals, a smaller population returns to the breeding grounds. But when there are fewer of them, the younger geese have higher chances of survival, so the population is soon back to its original level.' So shooting geese is what the Dutch call 'mopping with the tap open'.
Scaring them off or killing them does not help, as Rigter has found out for himself. Twice a week, local hunters have a go at the geese on his land. But they shoot no more than 150 geese in the whole winter season. 'The geese are getting smarter and smarter. If they see your car coming, they are off. You don't get a shot at them. Shooting doesn't get you anywhere.'
Research the breeding grounds
All this is just tackling the symptoms, says researcher Kleijn. To obtain a better overview of the costs, you should first get an idea of the growth of the goose population. And you cannot do that here; you have to go to their breeding grounds in northern Europe. Once you have ascertained the carrying capacity of those areas, you know what you are up against, says Kleijn. 'That is already done for the local summer geese. But for the barnacle geese and the white-fronted geese, which breed in the far north, nothing is known yet. Those species extended their breeding grounds when the populations increased after hunting was banned. There is a limit to the scope for that. If you know what that limit is, you can remove most of the uncertainty around the goose population growth and you know what the maximum costs will be in a few years' time.'/Roelof Kleis, Hans Wolkers
Welcome them or shoot them?
Can geese be managed more cheaply? Yes, according to LEI calculations. By no longer paying compensation outside special foraging areas. That would generate savings of almost twenty percent. The experts calculate that more intensive scaring off or shooting would cause four out of five geese to head for the nature reserves and foraging areas. But they do not know for sure. Geese do not tend to do as they are told. Active population management is an alternative. Thirty percent fewer geese would means savings of twenty percent. But then hundreds of thousands of geese would have to be killed every year. The LEI researchers do not think that is socially acceptable. They do have an idea for getting it more accepted though: promoting goose as an eco-friendly free-range meat. The biggest savings can be made by stopping the current policy. Do away with the special foraging areas, because they are costly. Then farmers no longer have to chase off geese, and they get compensation with an own risk of 300 euros. In short; back to the pre-2005 situation.