The flora and fauna around Frankfurt Airport are permanently influenced by the airport. Environment monitoring was developed as a means of evaluating the impact on the environment. For this purpose lichen and biotope mappings are carried out and the populations of frogs, dragonflies and stag beetles are observed.
The much-derided “frog counting”, which can indeed be interpreted literally as just that, is, however, only a means to an end. These creatures are so-called indicator species whose long-term development (in numbers) provides a reflection of the overall state of the natural environment. One could compare the procedure with political polls on TV which take representative samples to gauge the trends in political opinion in the population.  
Alongside flora and fauna, environment monitoring also focuses on aspects such as water, soil, climate, air and landscape.  
Suitable locations in the direct proximity, and thus within the sphere of impact of the airport, are selected for the analyses. For comparison purposes, the same analyses are carried out in areas further away which are not exposed to the direct influence of the airport. In this way the results from the areas in airport proximity can be more easily categorized and scientifically verified.
The aim is to recognise at an early stage possible negative impacts on the environment proceeding from Frankfurt Airport, and to counteract these as applicable. It is also possible to establish whether there are negative developments at other locations, and thus completely independent of the airport. This means that they must have other causes. Long-term observation is particularly important in the context of the environment as often the changes occur only very gradually and over a long period of time.