Species Notes for this Location:
Norway rats were first documented as coming ashore to New Zealand in 1773, from the ship Resolution, in Dusky Sound, Fiordland. Their numbers were observed to decline around the early 1900s (Moors, 1990; in Russell and Clout, 2004), and their impacts in New Zealand are primarily of historical significance, although they continue to be dominant on some smaller islands where one or more of the other rodent species are absent (Broome, 2004). Russell and Clout (2004) suggest that human modification of island ecosystems may be a factor in facilitating Norway rat invasion.
In New Zealand, Norway rats are regarded as wetland or riparian specialists, although on Stewart Island they were found some distance from water (Harper et al., 2005). They remain an important commensal pest, as they chew plastic fittings and spoil food (Innes, 2001).
Towns and Broome (2003) outline the history of rat eradications in New Zealand.