Effect of forest age on woodland amphibians and the habitat and status of stream salamanders in southwestern Québec

I studied two aspects of the ecology of amphibians in southwestern Quebec, an area characterized by a mosaic of small forests interspersed by cultivated land and by the presence of rare species at the northern limits of their distribution. One aim was to determine how forest age after clearcutting affected woodland amphibians. Path analysis was used to compare different causal effects of forest age on Plethodon cinereus density in 22 deciduous forests of 30, 60 and $>$90 years old. Repopulation of Plethodon followed forest litter recovery, 30 to 60 years after clearcutting. However, the effect of forest age was overridden by that of microtopography and soil texture. Rana sylvatica seemed also sensitive to clearcutting while Bufo americanus, Ambystoma maculatum and A. laterale seemed much less sensitive.A second aim was to determine the status and habitat of stream salamanders at the northern edge of the Adirondacks. Sixty stream sections were sampled. Eurycea bislineata was widespread (in 47 sites) and abundant, especially where rocks were numerous on the shore. The distributions of Gyrinophilus porphyriticus (8 sites) and, to a lesser extent, of Desmognathus fuscus (11 sites) were positively correlated with altitude and the presence of forest. It is proposed that these locations might offer the temperate and oxygenated waters needed by these species during winter and summer. (Abstract shortened by UMI.