Amphibians have to face multiple stressors, such as habitat fragmentation and exposure to agricultural chemicals (pesticides, fertilizers) in agricultural landscapes. The decrease of available habitat patches as well as habitat fragmentation and environmental pollution by agricultural chemicals are among the major causes for the observed global amphibian decline. Moreover, landscape elements (e. g.  flowing waters and hedges) and human activities (e. g. mowing and harvesting) may affect amphibian migration and occupancy of habitat patches. Therefore it is necessary to understand how anthropogenic land use influences habitat suitability and amphibian migration to improve conservation management. This includes migration between different terrestrial and aquatic habitat patches as part of the natural life cycle of amphibian species as well as genetic exchange between populations and colonization of new habitat patches through dispersal.

The chronological comparison of amphibian phenology and the applications of agricultural chemicals (in vineyards) indicated that applications were performed during all major migration events. Such major migration events contain immigration and emigration of adult amphibians as well as migration of juvenile amphibians. This is critical as juveniles play a major role for the dispersal of amphibian species as well as the viability of populations. The fragmentation of breeding pond populations could imply genetic consequences like genetic drift and inbreeding, especially when population size is already small. Furthermore diseases like chytridiomycosis and rana virus can also act as additional stressors.

Therefore we register amphibian breeding ponds in agricultural areas. Some of these breeding ponds will be selected for amphibian sampling to determine the current genetic condition of breeding pond populations and to check for the presence of diseases.

Pre-study: Expert-based modeling approach for assessing the effect of agricultural management measures on amphibian migration

The decrease of available habitat patches as well as habitat fragmentation and environmental pollution by agricultural chemicals are among the major causes for the observed global amphibian decline. The fragmentation of suitable habitat patches is mainly driven by the increase of agricultural areas, which represents the dominant human land use. In addition, roads and railways may affect local amphibian population viability by reducing and isolating suitable habitat patches. Moreover, landscape elements (e. g. flowing waters and hedges) and human activities (e. g. mowing and harvesting) may also affect amphibian migration and occupancy of habitat.

Pond breeding amphibian populations operate at multiple scales, from the individual breeding pond over surrounding habitat patches to clusters of breeding pond populations. The connectivity among breeding ponds as well as the availability of suitable terrestrial habitats surrounding breeding ponds plays a major role in long-term viability of amphibian species. Besides road traffic also agricultural land use can disrupt this connectivity due to pesticides, fertilizers and tillage operations. In the vineyards of Palatinate (Rhineland-Palatinate, Germany) pesticide applications are conducted during immigration and emigration of adult amphibians as well as the emerging of juveniles.