At present, every fourth mammal species is listed as endangered in red lists at the global level, one of them being the European field hare (Lepus europaeus) which is declining all across central Europe. Besides other reasons, agriculture is primarily hold responsible for the decreasing numbers of this animal species. Field hares are typical residents in agricultural plots using a wide spectrum of different crops.

To assess different crop production practices regarding their impacts on field hares the following assessment parameters were taken into account:

1. the suitability of the crop type to provide food resources and give cover,
2. the time- and operation-related risk potential of single operations to disturb, harm or kill animals during their reproduction period from the end of January to late September, with the highest sensitivity in May and June as most leverets are born in this time period,
3. the number of pesticide sprayings which are mostly linked to indirect effects, such as the availability of additional food resources like crop accompanying wild flora species and
4. the risk associated to the application of nitrogen fertilisers influencing height and density of the vegetation and therewith microclimate, coverage and establishment of accompanying wild flora species within the crop stand as an extra nourishment.

All alternative production practices of all crops defined for the model were assessed by their goal achievement levels using a fuzzy logic tool with the optimum being a zero risk for field hares to get negatively affected by agricultural activities.

Best results were calculated for permanent and rotational set aside. Grassland, alfalfa and grass clover mixtures for forage use scored well, too. Summer cereals got good marks as well, and were slightly better assessed than winter cereals. The worst ratings were given to sugar beets, silage corn, potatoes, and sun flower.