The impact of industrial fluoride fallout on faunal succession following sand-mining of dry sclerophyll forest at Tomago, NSW, II. Myobatrachid frog recolonization Original Research Article

We examined the response of frog species, recolonising dry sclerophyll forest following sand-mining, to the added impact of fluoride pollution from an aluminium smelter. Pitfall trapping was used to survey a chronosequence of sites at 3, 8 and 20 years post-mining at three nominal levels of fluoride contamination (background, low and high). Frog species, from the family Myobatrachidae, showed the following successional pattern of species replacement with increasing time after mining: Limnodynastes dumerilii, Crinia spp. (tinnula and signifera), L. peronii, U. laevigata. Frog species appear to enter the succession as their species-specific habitat requirements are met. Fluoride fallout, by affecting vegetation structure, alters the path of the succession of frog species. At 3 years post-mining, an increase in understorey density at the low fluoride level appeared to accelerate the succession of frog species. However, by 20 years post-mining, decreased canopy cover attributed to fluoride fallout is associated with a retardation of frog succession. There was little frog activity at extremely high levels of fluoride contamination, perhaps as a direct result of toxic effects.