Geographic variation in advertisement calls of Crinia signifera (Anura : Myobatrachidae) in the Bass Strait area of south-eastern Australia

Abstract

The structure of recorded advertisement calls of a total of 176 males of Crinia signifera from eight localities on the south-eastern Australian mainland and Tasmania was investigated. On the basis of number of pulses per call (samples from all localities) and call duration adjusted to 13.0°C (samples from six localities), two geographic groups are recognised: (1) south-central Victoria, and (2) the extreme south-eastern mainland and Tasmania. This pattern of variation is postulated to reflect expansion of a differentiated Tasmanian stock on to the extreme south-eastern Australian mainland along the eastern sill of the Bassian Isthmus during the lower sea levels of the Late Pleistocene. Geogr..