Variations in the temporal and spectral characters of advertisement calls by males of the foam-nesting treefrog Rhacophorus arboreus were studied. The advertisement calls had 2 to 6 notes. The interval between notes became longer within a single call. The interval between notes was negatively correlated with temperature but not correlated with body size (snout-vent length, body weight or mouth width). The frequency of a note became higher within a single call. Snout-vent length, body weight and mouth width were negatively correlated with the frequency. However, snout-vent length and body weight were correlated with the frequency of the call in different ways.
vocalization, advertisement call, variation, anuran, Rhacophorus arboreus