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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.

An invasive alien species are known to cause significant economic and environmental damage. Islands are much more vulnerable to the invasion of invasive alien species, and have higher rates of extinction. In the islands of the South Pacific, there are several species Polynesian land birds which are threatened with extinction due to invasive alien species and human interference. Without any intervention from humans, it is likely that these birds will suffer extinction in the next few decades. The island of Atiu in the Cook Islands (South Pacific) supports a range of avian fauna. In 2007 the Rimitara lorikeet (Vini kuhlii), also known locally as the ‘Kura’ was introduced to Atiu, to make a reserve population, as there were only approximatley 1000 left on the island of Rimitara, French Polynesia. There is concern for this species on Atiu due to the existence of the common myna (Acridotheres tristis). The myna is an aggressive invasive which is one of the world’s worst 100 invasive species. It was introduced to the Cook Islands by the government, with the intention to control the coconut-stick insect (Graeffea crouani), but is now a pest itself. A myna control programme on Atiu is being coordinated and controlled by Gerald McCormack (Cook Islands Natural Heritage Trust), working through George Mateariki, and using funding from various conservation organisations. Poisioning is being carried out by George in order to reduce myna numbers, and a bounty has been set on the birds or for every right foot so that the locals can help as much as possible. This investigation aimed to estimate the total population size on the island to use as a starting count to determine whether the programme is successful or not. Two methods were used which included roost counts to find an estimate of the population, and a transect method using a Distance programme to estimate the number of birds per hectare as well as the level of abundance in various habitat types. The two methods had overlapping results, giving a total estimated range of 3250 to 8460 birds on the island, although it is more likely to be at the higher end of this estimate at around 6000 to7000 birds. Further investigation will need to determine any change in the population size, any changes in habitat composition as well as the impact on the native species, especially the effect on the Kura and its population size.