Research Methods

Besides the research itself, constant, on-site monitoring, in cooperation with foresters, hunters and ornithologists, is particularly important, as well as dialogue with grouse experts. The chosen methods and research approaches were discussed with and determined by capercaillie experts from the whole of Europe. The project’s research work is subdivided into four modules:

Spatio-temporal Behavior

In order to understand how capercaillies live and move, their occurrence will be examined using different methods. Indirect signs of their presence will be gathered. In summer, feathers and droppings will be collected, and sightings and tracks will be documented. There is already information on where the animals can be found. Data on forest structures will also be recorded, in order to assess habitat quality.

In study areas with large capercaillie populations (e.g. in Sweden), telemetry work will be carried out within the framework of the project. In order to do this, birds are fixed with transmitters, through which their movements can be tracked over an extended period of time, and then later reconstructed. The information is most valuable if the transmitter is already on the animal before the construction of a wind energy facility. In this case, behavioral information from before, during and after construction can be collected.

Stress Physiology

In the coming years, in the Black Forest and Austria, capercaillie droppings will be collected and analyzed before and after the construction of wind energy facilities. The degradation products of stress hormones are found in droppings and can be tested for. In order to be able to make a statement about the stress level of birds, the droppings must be quite fresh. As such, in winter, immediately after a snowfall, droppings are gathered and analyzed in the laboratory. In doing so, one can determine if the construction of wind energy facilities detectably influences the stress levels of capercaillie. 

Reproduction

Each year capercaillie offspring will be counted within the framework of this research project. In late summer, a transect (i.e. predetermined route) will be followed. Capercaillie will be counted along this transect and classified as cock, hen or chick. Finally, an index will be devised in which the reproductive issue of the year will be determined. In order to minimize the disturbance of breeding and brooding, these methods will be carried out in late summer, in dry conditions, after the chicks have fledged.

In the Swedish study areas, the reproduction success of capercaillie will be estimated in areas with and without wind turbines using pointing dogs. The use of pointing dogs for wildlife monitoring and research is predominantly known in countries with a tradition of hunting e.g. Italy, Great Britain and Scandinavia. By using well-trained dogs the probability of finding present birds highly increases and thus makes it more effectively, allowing researchers to find and count broods systematically over large scales. The project receives support in this matter by the non-profit organisation Wildlife Detection Dogs e.V and the Swedish Environmental Protection Agency.

Population Connectivity

Because the capercaillie population in the Black Forest occurs exclusively at higher altitudes,it is crucial for its long-term survival that capercaillies are able to move from peak to peak. This occasional exchange of genes ensures that there are no occurrences of inbreeding in the population. Currently, several corridors between capercaillie subpopulations are known. The basis for this knowledge are investigations from 2003. Because some corridors are also currently in wind energy exclusion zones, these areas will be reviewed once again to determine any potential changes since 2003.

Since it is unlikely to observe birds flying these corridors, genetic material will instead be analyzed in a laboratory. By means of genetic analysis, the existing genetic exchange between regions can be determined. However, the results give no information about whether or not a wind turbine hinders the exchange between areas.

In addition to the feathers collected in summer, the droppings collected in winter will also be analyzed. It is then possible to identify individuals and assign them to the study areas. Additionally, the relationship between the birds can be reconstructed using this method. This can be used to determine where important connective corridors exist and what significance they play in the population’s connectivity.