Evaluating the living conditions of free ranging animals by automated chronobiological analysis of behavior
K.M. Scheibe1, A. Berger2, S. Michaelis1 and J.W. Streich2
1Institute for Zoo and Wildlife Research, Berlin, Germany
2IZW, Berlin, Germany
A biorhythmical method has been developed to assess behavior levels and evaluate the living conditions of free-ranging animals. All kinds of continuous and equidistant long-term recordings of behavior are suitable for this method. Data sets from automatic telemetry systems, such as ETHOSYS, are especially convenient and have been widely used.
Time functions can be analysed both macroscopically (comparison of daily levels) and microscopically (autocorrelation function and power spectral analysis). Harmonic Parts (HP) and Degrees of Functional Coupling (DFCs) can be calculated to identify and evaluate disturbances under usually quasi-natural conditions. Hierarchical frequency tuning of the organism, in the context of complex rhythmic behavioral functions, leads primarily to period lengths which are synchronised with the 24-hr period.
HP analyses calculate the percentage of rhythmic behavior synchronised with the 24-hr period. DFCs are a measure of harmony between internal rhythms and the external 24-hr period. These values are high in well-adapted, healthy and undisturbed individuals, but lower under conditions of adaptation, sickness or social interaction. All procedures have been tested on different species under various conditions. The different methods are available as a Windows-compatible software package.
Paper presented at Measuring Behavior 2002 , 4th International Conference on Methods and Techniques in Behavioral Research, 27-30 August 2002, Amsterdam, The Netherlands