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While invasive species eradications are at the forefront of biodiversity conservation, ant eradication failures are common. We reviewed ant eradications worldwide to assess the practice and identify knowledge gaps and challenges. We documented 316 eradication campaigns targeting 11 species, with most occurring in Australia covering small areas (b10 ha). Yellow crazy ant was targeted most frequently, while the bigheaded ant has been eradicated most often. Of the eradications with known outcomes, 144 campaigns were successful, totaling approximately 9500 ha, of which 8300 ha were from a single campaign that has since been partially re-invaded. Three active ingredients, often in combination, are most commonly used: fipronil, hydramethylnon, and juvenile hormone mimics. Active ingredient, bait, and method varied considerablywith respect to species targeted,which made assessing factors of eradication success challenging. We did, however, detect effects by active ingredient, number of treatments, and method on eradication success. Implementation costs increased with treatment area, and median costs were high compared to invasive mammal eradications. Ant eradications are in a phase of increased research and development, and a logical next step for practitioners is to develop best practices. A number of research themes that seek to integrate natural history with eradication strategies and methodologies would improve the ability to eradicate ants: increasing natural history and taxonomic knowledge, increasing the efficacy of active ingredients and baits, minimizing and mitigating non-target risks, developing better tools to declare eradication success, and developing alternative eradication methodologies. Invasive ant eradications are rapidly increasing in both size and frequency, and we envisage that eradicating invasive ants will increase in focus in coming decades given the increasing dispersal and subsequent impacts.

This study reports on a preliminary assessment of storm surge risk from tropical cyclones at Rarotonga, Cook Islands. Analysis of a 175 year record of cyclones from the Cook Islands indicates minimum annual probabilities of 16% for storm surges and 5% for major storm surge impacts at Rarotonga. Storm surges have historically inundated areas of the coastal lowland where virtually all human activities and infrastructure are currently located. The impacts of such events have been particularly severe in the Cook Islands' capital of Avarua and adjacent communities on the north coast of Rarotonga. Detailed infrastructure mapping combined with analysis of historic storm surge impacts and cyclones tracks in the vicinity of Rarotonga indicates that the storm surge risk is greatest along the north coast where the majority of the Cook Islands' government functions and commercials, industrial, transportation and communication infrastructure is located. Damage to this infrastructure at the shoreline can have serious repercussions throughout the Cook Islands. Any efforts to increase the country's resilience to such impacts must be undertaken within the larger goal of adaptation to future climate changes and rising sea levels. The greatest risk presently to human life arises from many cyclone safety centres in locations where they are exposed to storm surges or flooding. A top priority should be relocation of these shelters to safer locations further inland so that they can provide suitable shelter from storm surges and flooding as well as tsunamis, taking into account other hazards presented by Rarotonga's rugged topography.