Wheat or barley?: Feeding preferences affect distribution of three rodent species in agricultural landscape

Spatial distribution of voles and mice and their abundances in agricultural landscape are largely influenced by their food preferences and the distribution of preferred crops. Here we examined the correspondence between food preferences of dominant rodent species (two mice and one vole) for two cereals (wheat and barley) estimated in the lab and the long-term field abundances observed at the harvest time in southern Moravia, Czech Republic. In the first laboratory trial, harvested culms of wheat and barley were offered. The pygmy field mouse preferred (100%) the seed head of wheat, also the wood mouse (87%) and common vole (60%) showed low preference for wheat. In the second trial, we observed similar preferences in consuming the offered grains of both cereals, the wheat being preferred by the pygmy field mouse, and the wood mouse, while with the common vole showing no preference. Laboratory analysis of the harvested grains indicated a lower fibre content in wheat compared with barley. In the field, rodent abundances in wheat were higher than those in barley, especially in mice. This suggests that food preferences in the laboratory correspond closely to field distribution of these rodents and their abundances. Therefore, studying diet preferences may be of essential in predicting small rodent abundances in changing agricultural landscape.