Rodent food quality and its relation to crops and other environmental and population parameters in an agricultural landscape.

The diet, its quality and quantity considerably influence population parameters of rodents. In this study, we used NIRS methods for estimation of nitrogen content in stomachs of rodent populations. The study was carried out in diverse arable landscape in South Moravia, Czech Republic. Rodents were sampled in cultural crops (alfalfa, barley, wheat, sunflower, maize and rape) as well as in fallow habitats (herbal set-aside and old orchard). Influence of habitat, date, year, individual parameters (body length, sex, breeding and age), and relative abundance on quality of consumed food was studied. Under conditions of higher population density, dominant species [wood mouse (Apodemus sylvaticus) and common vole (Microtus arvalis)] consumed food richer in nitrogen. Also the strong effect of crop and date (season) was found in both species. There was no significant effect of the other parameters studied on food quality (N-content).