Can Australian bush birds be used as canaries? Detection of pervasive environmental impacts at an arid Australian mine site

Abstract

A 13-year spatially-replicated monitoring program was analysed to determine avifauna responses to disturbances associated with proximity to a mine in arid Australia. Crested Bellbirds (Oreoica gutturalis), Grey Butcherbirds (Cracticus torquatus), Red-capped Robins (Petroica goodenovii) and Chestnut-rumped Thornbills (Acanthiza uropygialis)were consistently recorded in lower abundances near the mine compared with more remote sites possibly in part due to acoustic masking of their calls. These species were therefore useful indicators of the degree and extent of pervasive mining disturbance, beyond the direct physical effects of mining. By contrast, a suite of synanthropic bird species, or those species that benefit from association with human-made elements of their habitat, were recorded in higher abundances adjacent to the mine. The gradient effect of distance from impact on the key bioindicators was clear, with a significant factor-change difference in a composite measure of bioindicator variables. Despite considerable temporal variation in individual species abundances, we also show that differences associated with proximity to the mine are relatively stable for species richness and for some bird species. Our data demonstrate that the ability to detect pervasive environmental impacts of mining disturbances on avian assemblages is greater when excluding synanthropic species.