Practical examples
Two examples illustrate how monitoring “on site”, i.e. in the area around the airport, functions. These involve a survey of insects and a survey of a frog population. So far, therefore, there is not a lot to see. The most important phases of monitoring are the evaluation and documentation of the results “on the desk”, not so much the work in the field.
Insects...
- Spawning biotope for frogs
Surveys in the field
At various measurement stations insects are automatically trapped with the aid of a so-called trunk eclector trap and counted monthly.
The eclector traps insects crawling up or down the trunk of the tree – in the spring usually in the direction of the crown and in autumn in the opposite direction.
Alongside the stations in Kelsterbach Forest and the forest islands between the airport and the motorway/railway, there are also reference stations in Frankfurt City Forest which are unaffected by the airport.
(Photos: UNH, 2010)
...and frogs
- Laichbiotop des Springfrosches
- Laichballen des Springfrosches kurz vor dem Schlüpfen
Counting frogs
Alongside insects, the frog is another important indicator species.
To determine the population development, the frogspawn is counted every spring at specified spawning biotopes.
Particularly in the case of frogs, developments can only be assessed over a long period of time, because the population tends to fluctuate widely even without human influences.
(Photos: UNH 2010)