Wetenschap - 24 februari 2011

8,000 pairs of ears and eyes

With about 8,000 volunteers, the Nature Calendar has grown into the Netherlands' biggest public platform for nature observation in the space of just ten years. The Wageningen website is a public favourite and a big PR success, but its founder Arnold van Vliet does not lose sight of its scientific purpose.

About 1,500 newspaper articles in ten years is a publication score that no other Wageningen group can dream of equalling. And that does not include countless appearances on TV, on the news and on a popular radio nature programme. Who is it who is achieving all this? Arnold van Vliet, the founder of the Nature Calendar. 'I certainly wouldn't have predicted this ten years ago', says the celebrity biologist in his office at Environmental Systems Analysis in the Atlas building on the Wageningen campus. 'But the main thing of course is that this gives us a big impact. The Nature Calendar makes climate change visible for a broad public, right up to our own back yards.'
More than ten years ago, Van Vliet set the scene for his publishing success in the Sunday morning radio programme 'Early Birds', on which he spoke of his enthusiasm for phenology, the study of the influence of weather and climate on seasonal phenomena in nature, such as flowering or the migration of birds. During the interview he hit on the idea of asking listeners to send in their own phenological observations. 'Pretty naïve', he thinks now. 'I had absolutely no idea at that point that half a million nature lovers listen to that programme. Within two weeks, 2,000 volunteers had signed up. We had to keep them informed; we had to make forms and send them round, while we really didn't have anything up and running yet.
Today the Nature Calendar has developed into a well-oiled machine revolving around the website www.natuurkalender.nl, which provides not just observations and information about plant and animal species but also a forecast - which plants, butterflies and dragon flies can be expected at the moment - and a news service: Natuurbericht.nl. A team of three part-time colleagues of Van Vliet's and a number of related organizations help run the website and analyse the data, which are provided by at least 8,000 registered observers (mainly aged between 45 and 65, numbering slightly more women than men, and evenly distributed over the country). Between them the volunteers keep track of nearly three hundred species of plants and animals. 'There are many people who always record nature-related data, just in an exercise book. I think they like the idea of their observations contributing to scientific research', says Van Vliet. 'There are some people among them with considerable knowledge of nature, but we keep the threshold low on purpose. Anyone who can recognize a snowdrop can take part.'
Jeannette's first curlew
'Today I heard the cry of the curlew for the first time: that wonderful yodel', says Jeannette Essink from Koekange in Drenthe. 'The first one every year, that gives you a kick, when a bird is suddenly back, a flower blooms again; it is a kind if reunion with old friends. In 2006 my first sighting of the curlew was on 18 February as well; in other years it has been a couple of days earlier.
Essink was one of the Nature Calendar reporters right from the start. She is also a regular caller to the 'Pheno phone-in', a fixed feature of the Early Birds radio programme. 'If you feel closely involved in something, the way I do with nature, then you like talking about it with others, and sharing your pleasure with them. I always kept records of my nature observations; thanks to Arnold something useful is now being done with them', says Essink. 'When we still lived in Bennekom, I was a member of the Birds working party of the KNNV and I also led field trips through the Binnenveld for the IVN. But I have never worked with nature professionally. I have built up my nature knowledge gradually over the years. A specialism? No, I am a real omnivore. We moved here to Drenthe because I was so keen to create a natural garden. That's where I observe most things, and also when I am out walking the dog of course.'

Doesn't your database get messed up by mistakes, or even by deliberate hoaxes?
'Of course we occasionally get observations sent in by people who are just having us on, or who are clearly mistaken. On the other hand, you shouldn't dismiss all extreme observations out of hand. In 2007, due to warm conditions, cow parsley was blooming in January. In order to prevent the extreme cases - dates of leaf development for example - having a disproportionate impact, we base our conclusions on the median data. If we get 30 sightings, then we have a reliable picture of that particular year.'

Do you always manage that?
'Not always. We get very little data in about the turning of the birch leaves in the autumn, for example. Fortunately you do have school classes then; they do send in a lot of autumn observations through the Nature Calendar education programme. What has been a failure on the whole is the collection of data on agricultural crops. We have not been able to interest the farmers at all in these ten years. Perhaps the Nature Calendar has too much a nature-lover image, or perhaps our link with 'Early Birds' worked against us, since the programme has been known to criticize the farming sector. But the frustrating thing is that in many other European countries, agricultural crops are playing an important role in the phenology networks. That this does not work here is something that annoys me quite a lot. Why? Well, this is Wageningen University, after all.'

What about your academic output? Can you base scientific findings on these observations?
'A couple of years ago a meta-analysis was carried out, partly with our help, using long-term phenology data from 21 countries. The results of this played an important role in the conclusions of the IPCC on the impact of the climate on nature. So our volunteers do provide us with important input for research. We do still have to do some catching up on publishing more results. There is a vast amount of material but at the moment it is very difficult to get funding for applied research: we do not have a single doctoral research project at present. Perhaps that is partly because people think of us as primarily a communication channel, rather than as scientists.'

But science is the essence of a university.
'Science is absolutely the basis of the Nature Calendar. And then, happily, publications in the popular press are also becoming more important to the research community. In an evaluation by the research school SENSE, Environmental Systems Analysis came out as the best environmental group in the Netherlands, partly because of the social relevance.'

Are the media not beginning to get tired of you?
'I don't get that impression; on the contrary. All those newspapers, websites and radio and TV programmes need to be filled every day.  Our strength lies in our day-to-day relevance, our frame of reference and our visibility. If the meteorologists report that the spring has been unusually warm, the Nature Calendar can chip in straightaway with the news that the celandine is flowering two weeks early. If a camera crew comes along, we go and look at the celandine. And it is especially good if we can offer a possible explanation, or if there is a link with socio-economic themes. That is becoming increasingly important to us too, for creating new income sources.

Do you need those?
'My salary is paid by the university; we have a few sponsors but in the long term the Nature Calendar needs a broader basis. The struggle for funding forces us to think up new projects all the time and make new contacts. We are opportunists in that respect; if we see an opportunity we seize it. At the moment, for example, there are consultations going on about collaboration with Wegener's regional dailies. We are also focussing more and more on social issues that are related to nature's timing. I think health issues will gain prominence in the work of the Nature Calendar in the coming years.

Health? Isn't that outside your field?
'Not as much as you might think. One example is Allergieradar.nl, a collaboration with Leiden University Medical Centre and others. There are now 1,200 patients reporting on the seriousness of their symptoms and we can correlate that data with the blooming time of a range of plants. Eventually this should lead to better hay fever forecasts. Many hay fever medicines only work if you start taking them well before the season starts, so early warning can make a big difference to the amount of sick leave being taken. And the Nature Calendar can play a role there too.'

Insect safari
For the Nature Calendar's tenth anniversary, Arnold van Vliet and a big group of other organizations are going to run a festival called INSECTexperience, about both the nice and the nasty sides of creepy crawlies. The festival will kick off at Cinemec, Ede, on 25 May with an evening of 3-D films about insects, stand-up comedy and educational events. Over the following days there will be an insect film festival, a symposium for nature and estate managers, and a training course for teachers in secondary and 'green' education on how they could teach about insects. The climax comes on Saturday 28 May with a big public event in the Forum and Radix. Visitors will be able to go on an insect safari underground, under water or in the air. The 8,000 reporters of the Nature Calendar will be invited to this day. 'We have never done anything for all those people', says Van Vliet. 'We thought it would be nice to invite them to Wageningen so we can meet up.'