By Joern Fischer
I’d like to share key points from a recent paper led by Ine Dorresteijn on the Corncrake (Crex crex). It’s one of the most charismatic bird species in Europe, and has attracted the attention of a lot of conservationists. In landscapes where it remains common, it’s well known for its nocturnal calls “crex-crex-crex…”, which is where it got its name from.
Corncrakes have disappeared from most of Western Europe. Where the species does persist, it is most commonly associated with extensive, wet meadows. But what about in landscapes where larger populations remain?
We studied the corncrake in Central Romania, where it seems virtually ubiquitous. It’s difficult to be out in the countryside at nighttime in June and not hear a corncrake sooner or later. We wanted to know what constitutes habitat for the corncrake in this traditional farming landscape – and our findings presented an interesting contrast to common wisdom on corncrake conservation.
We found corncrakes not only in grassland but equally in the direct vicinity of arable fields. Statistical analysis suggested that corncrakes seemed to prefer remote areas that were wet and flat, which is largely consistent with previous work. However, we also found that corncrakes were more likely to occur in areas with a high land cover diversity at the 100 ha scale. This suggests that traditional, heterogeneous arable land provides important habitat for the corncrake – and not just extensive areas of grassland.
This new finding has some important consequences for conservation. First, it suggests that focusing on grassland alone may not be enough; heterogeneous arable land also provides useful habitat for the corncrake, and may be equally worthy of conservation efforts. Second, the scale at which the corncrake responded to land cover diversity is relatively large (100 ha). This suggests that conservation management should not only promote measures taken by individual farmers. Rather, a whole-of-landscape approach is needed to maintain land cover diversity, and this by necessity will involve multiple landholders.
Finally, a simulation model suggested that even moderate losses of land cover diversity in the future would severely impact corncrake populations (see below). This sends a clear signal for landscapes such as those in Central Romania: to maintain this European hotspot of the corncrake, it’s important to maintain the diverse character of the landscape.