Modell für den schutz des wachtelkönigs Crex crex

The Corncrake (Crex crex) is a globally threatened bird species that breeds in grasslands. Traditional conservation schemes aim to delay mowing dates to enhance nestling survival during mowing, but are unpopular among farmers because of the loss in revenue In this paper, we propose a new approach to Corncrake conservation involving differential mowing of areas within the grassland. The rationale underlying this approach is that areas cut prior to the main mowing date provide places of refuge for the nestlings when the bulk of the grassland is mowed. We present evidence that the ability of nestlings to walk to nearby refuges is age-dependent and we develop a model to calculate the effect of differential mowing on bird survival and the profit of the farmer. The model also shows that grassland should be mowed in strips to enhance corncrake breeding success.