The role and nature of Tara taranaki are described. Its links to other species are considered; and the possible effects of possums on the species is discussed. It is likely that 1080 poison is highly toxic to amphipods, but no matter how poisonous it is to Tara taranaki, its use is likely to be far less damaging in the long term to this species than are the effects of an uncontrolled possum population.

New Zealand, an archipelago of more than 2000 islands, has a terrestrial fauna especially depauperate in native land mammals. Kiore (Rattus exulans) was the first of four rodent species introduced by people. A project to eradicate invasive rats from Kapiti Island in 1996, represented a turning point in the technology, complexity and scale at which managers of natural heritage on New Zealand islands could operate. This paper includes case studies of some significant projects targeting rodents, sometimes with other introduced mammals, undertaken in the 12 years following Kapiti.