The ecological impacts of commensal species: black rats, Rattus rattus, at the urban–bushland interface

摘要: Exotic species have had devastating impacts worldwide and are a major threat to native wildlife. Human commensal (hereafter commensals) special class of exotic that live largely off the resources associated with human activity. The encroachment commensals from an urban area into surrounding bushland has been frequently overlooked as important component impacts, even though human-commensals common many regions globally. In this review, we present theoretical empirical evidence for processes outcomes occurring when encroach bushland. Specifically ask when, how why bushland, what determines whether they establish, ecological consequences. We focus on black rat, Rattus rattus, arguably archetypal cosmopolitan distribution greatest potential damage all rodents. expect outline apply other more broadly. argue in fact natives milieu only become alien peri-urban propose mechanisms will be different those other, non-commensal because areas act dispersal hubs overcome barriers invasion face. suggest resource supplementation by creates great promoting encroachment, well impact. However, biotic abiotic still relevant commensals, highlighting need maintain integrity ecosystems wildlife populations edges so prevent incursion. examine rats affect via three fundamental mechanisms, namely, predation, disease transfer competition resources, also consider their possible positive acting functional replacements lost natives. conclude review research priorities future directions essential progressing our understanding ecology species.