Review of impacts of the introduced house mouse on islands in the Southern Ocean: are mice equivalent to rats?

Research on the impacts of house mice Mus musculus introduced to islands is patchy across most of the species’ global range, except on islands of the Southern Ocean. Here we review mouse impacts on Southern Ocean islands’ plants, invertebrates, land birds and seabirds, and describe the kinds of effects that can be expected elsewhere. A key finding is that where mice occur as part of a complex of invasive mammals, especially other rodents, their densities appear to be suppressed and rat-like impacts have not been reported. Where mice are the only introduced mammal, a greater range of native biota is impacted and the impacts are most severe, and include the only examples of predation on seabird eggs and chicks. Thus mice can have devastating, irreversible and ecosystem-changing effects on islands, impacts typically associated with introduced rats Rattus spp. Island restoration projects should routinely include mouse eradication or manage mouse impacts.