Early and late colonizers in mine site rehabilitated waste dumps in the Goldfields of Western Australia

Abstract

We examined the abundance of reptile and mammal species on five rehabilitated waste dumps in the early successional stages in the mined area around Ora Banda in Western Australia and compared these data with species richness and abundance in adjacent undisturbed areas. Mammal species common in the undisturbed areas were also found in relatively high abundance on waste dumps, with the exception of Pseudomys hermannsburgensis. In contrast, not all reptile species in the adjacent undisturbed areas had colonized waste dumps. However, a high proportion of those reptile species that were caught on rehabilitated waste dumps were at lower numbers than in the adjacent undisturbed areas, indicating that they were slow colonizers. Reptiles Underwoodisaurus milii, Heteronotia binoei and Pogona minor and mammals Mus musculus and Sminthopsis crassicauda are among the early colonizing species that flourish in the developing ecosystem on waste dumps. Species able to exploit a diverse range of niches, tolerate open spaces, have a generalist diet and good dispersal capabilities are the early colonizers. In contrast, species with a specialist diet or micro-habitat requirements are slow to colonize rehabilitated waste dumps and will initially be represented in low numbers. We encourage mining companies and regulators to change the size and shape of waste dumps, and to seed with species found in the adjacent undisturbed areas to hasten the colonization of vertebrate species on to waste dumps and the creation of functional ecosystems.