| dc.description.abstract | The purpose of this investigation was to use current methods of bioacoustic analysis to
determine whether the environmental parameters of water temperature and background
noise significantly affect the characteristics of male Pelophylax lessonae (Pool frog) mating
calls. The secondary purpose was to ascertain whether call characteristics (call length, pulse
length, pause length, number of pulses, and peak frequency), are useful indicators of frog
activity. This study was conducted during the predicted peak mating season, over a period
of several months. Environmental readings of the study site were obtained using a variety of
primary and secondary research, whilst frog calls were recorded using a microphone. Linear
regression modelling was used to determine to what extent water temperature and
background noise explained the variation in each call characteristic. Analysis of call
characteristics produced results which suggested that call length, pulse length, pause length
and number of pulses are significantly influenced by environmental parameters. As no
relationship was found between peak frequency and the environmental parameters,
alternative methods of study and predictor variables for peak frequency were put forward.
It was also concluded that environmental parameters vary in their influence upon frog calls
and that variance of each environmental parameter must be considered when studying their
effect on frog calls. Emphasis is put on the great extent to which background noise
influences call length and pause length, as this is a new development in the field of
bioacoustics. Call characteristic analysis were found to be a very useful study method for
several interactions, not limited to environment. The call characteristics which showed a
relationship with the environment also proved to be useful indicators of frog activity, as frog
activity is intrinsically linked to changes in in water temperature. | |
