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The Ua Pou islets Pacific rat eradication operation was undertaken in August-September 2023. It attempted a global first of aerially broadcasting rodent bait by drone from a small ship in open sea across the islets of Motu Tākaè, Motu Oa, and Motu Mokohe, at Ua Pou in the Marquesas Islands. The aerial bait application resulted in only two of the three islands having bait successfully applied across their entirety, nonetheless, monitoring 12 months later has confirmed Motu Oa and Motu Tākaè are rat free as is the partially isolated section of Motu Mokohe that was also baited. The eradication success is supported by the establishment of biosecurity knowledge and practices throughout the Ua Pou communities. The results of the seabird and other environmental monitoring will help sustain a commitment over time, as well as benefiting the wider conservation community. The operation demonstrated that drones could be operated off a boat for rodent eradication purposes but was constrained by the consistently strong winds and swell conditions. A larger vessel with a deeper draught is recommended for similar operations in the future and would likely increase the number of flyable days and improve the ease with which take-offs and landings are undertaken by the drone pilots.

The tropical Marquesas islands are characterised by their isolation and high levels of endemicity among native fauna and flora. This includes forty-two percent of the 320 native vascular plants and a diverse terrestrial snail community, with at least 78 species represented. Of the 12 native land birds 11 occur only within the archipelago, several restricted to a single island. Nineteen species of seabird breed there including the most eastern population of the Endangered Phoenix Petrel. Monitoring of seabirds and other species before, during and after the project will inform the impact of removing rats from these islets including how endangered species respond and community interest.

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.