Every eighth bird species is documented as threatened at the global level, one of them being the Skylark (Alauda arvensis) that is declining all across Europe. Skylarks are typical residents of agricultural areas which they use as their feeding and reproduction habitat. They feed on insects and other arthropods, seeds and grains. Breeding and raising of chicks takes place from April until July. Intensive agricultural management practices are seen as the main cause of endangerment.

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

1. the suitability of the crop type to provide beneficial breeding conditions, food resources and coverage for this bird species,
2. the time- and operation-related risk potential of single operations to disturb, harm or kill birds, or destroy nests and clutches during the reproduction period,
3. the risk associated to the application of nitrogen fertilisers influencing height and density of the vegetation and therewith microclimate, coverage and freedom of movement within the crop stand when looking for food,
4. the number of insecticide and herbicide treatments affecting the availability of food resources such as insects and seeds and
5. the application of growth regulators leading to a dense and high crop stand causing the abandonment of habitats as the bird prefers rather light and spare vegetation.

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 skylarks to get negatively affected by agricultural activities.

Best results were calculated for permanent and rotational set aside. Alfalfa and grass clover mixtures for forage use scored well, too. Grassland used as pastures scored better than grassland used for the production of hay and silage production due to the high number of operations taking place in the sensitive breeding periods. Summer cereals were assessed to be more suitable as winter cereals. The worst ratings were given to sugar beets.