Wetenschap - 29 november 2012

'Concentrate agricultural nature conservation

Since 1960 the Netherlands has seen three-quarters of the breeding population of its farmland birds disappear.

The skylark population has shrunk by no less than 96 percent, reveals the recently published State of the Birds in the Netherlands 2012  (Vogelbalans 2012). The figures come as no surprise to Professor of Nature Conservation and Plant Ecology Frank Berendse.
'Ten years ago I reported on the deterioration of our farmlands. Skylark numbers had already fallen by 85 percent. This deterioration has continued at a rapid rate. I am struck by the fact that the number of lapwings is falling rapidly too. Until now, this was one of the species that was managing to maintain a fairly stable population.'
Intensive farming is the culprit. So doesn't agricultural nature conservation help?
'No. Agricultural nature conservation is far from able to compensate for the effects of intensive farming. We demonstrated that incontrovertibly, and published our findings, years ago. In itself, mowing later in the year, the main element of agricultural nature conservation, is a good thing because it reduces the number of chick deaths. But we now know this is absolutely inadequate. That surviving chick will need to get enough food. And that means varied, sparse vegetation is needed. But mowing heavily fertilized, drained plots of land later produces dense, dark-green overgrowth. This is impenetrable for chicks. Meadow birds benefit from a high groundwater level and scant use of fertilizer. These are precisely the things that agricultural nature conservation typically does not address.'
Is there nothing we can do?
'On the contrary. We have to invest the money earmarked for agricultural nature conservation chiefly in large areas that offer a strong chance of success, preferably areas adjoining existing reserves for meadow or farmland birds. Areas where results can be achieved, where the groundwater level can be raised, where much less fertilizer is used and no herbicides and pesticides. This will give the birds a boost. I'm a member of the Nature and Landscape committee of the Council for the Environment and Infrastructure. Soon we will be advising the cabinet about the new nature policy. Our advice will certainly include this issue.'