Exotic species are found across the globe and can have dramatic negative impacts upon native wildlife.Recent work,however,has begun to highlight the importance of ecological function,suggesting that exotic species may serve some beneficial ecological role in the absence of their native counterparts.Conservation studies of exotic rodent impacts have largely been confined to island systems,even though exotic rodents are (i) highly commensal (ii) found across the globe and, (iii) may have the capacity to encroach into remnant bushland areas around cities and impact upon native wildlife.We examined the response of an invertebrate community to the removal of exotic black rats (Rattus rattus) (n=4) ,compared to sites with native bush rats (Rattus fuscipes) (n=4) ,and controls (n=8) .We hypothesized that (a) black rats use the arboreal zone more than bush rats and (b) the highest invertebrate abundance and diversity occurs on sites without any rodents.Surprisingly we found overall lower invertebrate richness and diversity on rat-free sites,and similar richness and diversity on sites with any rodent species present.We also found highest spider abundance on rat-free sites,indicating that some trophic cascade process may be occurring by rodents controlling spider density.We suggest that rodents appear to serve some positive role for invertebrates at the community level,and while exotic black rats are not a perfect substitute for bush rats,they are a better option than having no rodents there at all.