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Rodents remain one of the most widespread and damaging invasive alien species on islands globally. The current toolbox for insular rodent eradications is reliant on the application of sufficient anticoagulant toxicant into every potential rodent territory across an island. Despite significant advances in the use of these toxicants over recent decades, numerous situations remain where eradication is challenging or not yet feasible. These include islands with significant human populations, unreceptive stakeholder communities, co-occurrence of livestock and domestic animals, or vulnerability of native species. Developments in diverse branches of science, particularly the medical, pharmaceutical, invertebrate pest control, social science, technology and defense fields offer potential insights into the next generation of tools to eradicate rodents from islands. Horizon scanning is a structured process whereby current problems are assessed against potential future solutions. We undertook such an exercise to identify the most promising technologies, techniques and approaches that might be applied to rodent eradications from islands. We highlight a Rattus-specific toxicant, RNA interference as species-specific toxicants, rodenticide research, crab deterrent in baits, prophylactic treatment for protection of non-target species, transgenic rodents, virus vectored immunocontraception, drones, self-resetting traps and toxicant applicators, detection probability models and improved stakeholder community engagement methods. We present a brief description of each method, and discuss its application to rodent eradication on islands, knowledge gaps, challenges, whether it is incremental or transformative in nature and provide a potential timeline for availability. We outline how a combination of new tools may render previously intractable rodent eradication problems feasible.

During 10–21 September, quantitative surveys were carried out of birds and flying foxes using the same techniques as applied in earlier surveys, and searches carried out for a rare parrot and lizard. Bird counts showed that the lupe or Pacific imperial-pigeon population has recovered following a decline between 1994 and 2004 though the current hunting rate is considered unsustainable. Miti or Polynesian starling numbers have gradually declined over the period 1994–2012 which is a concern and hard to explain. Rat predation is a possible cause. There was also an indication that pekapeka or white-rumped swiftlet numbers have declined though more investigation is needed to confirm this. We were unable to find any hega or blue-crowned lory though a few individuals were reported to us. Numbers are clearly very low and the next step must be to gain a better understanding of where the species regularly occurs so that management can be applied

During 10–21 September, quantitative surveys were carried out of birds and flying foxes using the same techniques as applied in earlier surveys, and searches carried out for a rare parrot and lizard. Bird counts showed that the lupe or Pacific imperial-pigeon population has recovered following a decline between 1994 and 2004 though the current hunting rate is considered unsustainable. Miti or Polynesian starling numbers have gradually declined over the period 1994–2012 which is a concern and hard to explain. Rat predation is a possible cause. There was also an indication that pekapeka or white-rumped swiftlet numbers have declined though more investigation is needed to confirm this. We were unable to find any hega or blue-crowned lory though a few individuals were reported to us. Numbers are clearly very low and the next step must be to gain a better understanding of where the species regularly occurs so that management can be applied.

On 6 January 2004. cyclone Heta devastated much of the South Pacific island nation of Niue. Extensive damage was done to forest, particularly of the north- western sector, with many trees up-rooted and others stripped of branches and foliage. This report details our findings from a survey of Niue's birds and rodents during 3-19 September 2004 and compares these with results from a similar survey in September 1994. Five-minute bird count data, an index of conspicuousness, from three transects showed that heahea (Polynesian triller,Lalagc maculosa) were more abundant in 2004 than in 1994, but mid (Polynesian starling, Aplonis tabuensis), kulukulu (purple-crowned fruit dove. Ptilinopus porpbyraecus) and lupe (Pacific pigeon. Ducula pacifica) had declined. The 28-64% decline in the lupe population per transect w as probably primarily as a result of hunting, rather than mortality caused by cyclone Heta. Counts of birds seen per kilometre along three sections of road (lower, upper, inland) were also compared with September 1994 data. However, for various reasons we doubt that the results accurately reflect population numbers. The 212 kiu (Pacific golden plover. Pluvial is fulva) counted at sites accessible from main roads in September 2004 was similar to the 226 seen in September 1994. Rat trapping results (captures per 100 trap-nights) along the same three transects for December 1994 and September 2004 were not significantly different. Both kuma (Pacific rat. Rattus exulans) and ship rats (R. rattus) were trapped, but kuma were found only in regenerating scrub, whereas ship rats were present in both scrub and forest. Recommendations for future work are made mainly in relation to the long-term conservation of lupe, a toaga (treasured) species of Niueans.