The distribution and ecology of invasive ant species in the Pacific Region

*[This thesis examines the spatial distribution of invasive ant species at a range of scales. The focus is on the Pacific region, specifically Fiji and New Zealand, which have a relatively high number of invasive ant species. Checklist of invasive ant species recorded from the Pacific region are listed in Appendix 2.1. Checklist of ant taxa recorded from Fiji is given in Appendix 2.2. Endemic and invasive ant species recorded from New Zealand are listed in Table 5.2. A list of species intercepted in quarantine is included as Appendix 8.1. A better understanding of how climate variables directly and indirectly affect a species is needed to improve the utility of species distribution modeling. On a finer spatial scale, habitat partitioning was evident at Colo-i-Suva Park in Fiji, where distinct ant communities were sampled from litter and canopy habitats. Results suggested that body size, habitat and resource utilization interact to create opportunities for invasion, and influence the susceptibility of different habitats. Habitat also shaped the assembly of ant communities and mediated inter-specific competition in the Yasawa Islands, Fiji. Habitat was important in partitioning ant communities in New Zealand; endemic ant species were in forest, and invasive species in scrub and urban habitats. However, there was no evidence that inter-specific competition influenced community composition or the distribution of invasive ant species at regional or local scales in New Zealand. The extent & diversity of exotic ant species arriving at the New Zealand border was also investigated. More than 64% of intercepted ants originated from the Pacific. The effectiveness of detecting exotic ant species at the New Zealand border ranged from 48-78% for different pathways, indicating a number of species remain undetected.]

new, Aug 08