The effects of kiore, or Pacific rat (Rattus exulans) on indigenous species has historically been based on anecdotal accounts and circumstantial comparisons. The eradication of kiore from 220ha Tiritiri Matangi Island in 1993 provided an opportunity to obtain empirical data on the effects of this rodent on invertebrates. Long term monitoring of ground invertebrates began three months before the removal of kiore and continued for five years following removal. Pitfall traps were set in a mature broadleaf forest remnant and in a younger regenerating forest. Larger numbers of invertebrates were caught in the mature forest and these also increased to a greater degree after rat removal. Capture rates of several large (>10 mm) species increased during the study, including ground weta (Orthoptera: Anostostomatidae) and several species of prowling spider (Araneae: Miturgidae). Capture rates of other species that changed over time appear to be correlated with weather that varied dramatically during the period of monitoring. Seasonal changes are reported and the life histories of large flightless, nocturnal ground-dwelling invertebrates are correlated with kiore eradication.
|Author||Green, C. J.|
|Secondary title||International Conference on Eradication of Island Invasives|
|Publisher||IUCN Invasive Species Specialist Group|