STIP A, KLEIJN D & TEUNISSEN W (2013) Effects of the provisioning of food crops on the numbers of wintering granivorous farmland birds: a first analysis. LIMOSA 86 (3): 132-139.

Farmland birds have showed rapid population declines in Europe in recent decades. These changes are supposed to be caused by changes in agricultural practice. Among several other causes, the reduction in food supply is suggested to be the key factor determining farmland bird populations, with winter food availability being a possible bottleneck. This study investigated the effects of provisioning multi-species crop plots as a food source for seed-eating farmland birds in small-scale farming areas. Based on three bird counts over the winter of 2011/12 in ten matched pairs of sites, bird species richness and bird numbers were used to assess the effects on seed eating farmland birds. Each sites covered 100 ha and was paired with a comparable control area (Fig. 1). In experimental areas three different seed mixtures were sowed in plots of 0.4 ha each. We found significantly higher bird numbers in areas where we provided extra food crops (Fig. 2), and nearly significantly higher species richness. Dominance of species shifted remarkably between area types. Experiment areas harboured mainly seed-eating birds (62%) whereas control areas accommodated fewer of these (45%). Bird numbers were highest in January, suggesting an increased food shortage in late winter or migration to breeding areas. The results of this study suggest that provisioning winter food crops for farmland birds can be an effective conservation measure.

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