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House sparrows (Passer domesticus) compete with native bird species, consume crops, and are vectors for diseases in areas where they have been introduced. Sparrow eradication attempts aimed at eliminating these negative effects highlight the importance of deploying multiple alternative methods to remove individuals while maintaining the remaining population naïve to techniques. House sparrow eradication was attempted from Robinson Crusoe Island, Chile, in the austral winter of 2012 using an experimental approach sequencing passive multi-catch traps, passive single-catch traps, and then active multi-catch methods, and finally active single-catch methods. In parallel, multiple detection methods were employed and local stakeholders were engaged. The majority of removals were via passive trapping, and individuals were successfully targeted with active methods (mist nets and shooting). Automated acoustic recording, point counts and camera traps declined in power to detect individual sparrows as the population size decreased; however, we continued to detect sparrows at all population densities using visual observations, underscoring the importance of local residents’ participation in monitoring. Four surviving sparrows were known to persist at the conclusion of eff orts in 2012. Given the lack of formal biosecurity measures within the Juan Fernández archipelago, reinvasion is possible. A local network of citizen observers is the best tool available to detect house sparrows at low density, however ongoing, dedicated eradication funding does not exist. Opportunistic removals via shooting have been possible from 2013–2016, but elusive individual sparrows were seen during a small number of days each year suggesting remnant group(s) exist in yet unknown forest locations.

This plan sets out the operational detail, logistics and framework for a planned eradication of introduced Pacific rats from Late Island (1,731ha) in the Kingdom of Tonga. The method for the eradication is the delivery of grain-based bait containing the anticoagulant brodifacoum, into every potential rodent territory on the island. This will be done during the driest part of the year when rodents are potentially most vulnerable due to lower relative availability of natural food supplies. Because of the island’s size and complex topography, the bait will be applied aerially using a helicopter with an underslung bait spreading bucket. Aerial application has been successful in eradicating rodents from many islands around the world, and the logistics and methodology are based upon similar successful operations. Mitigation measures will be required for key non-target species, especially the Friendly-ground dove. Monitoring of rodents and native species before and after the operation will be required to assess the success and effect of the operation.

The Fourth Assessment Report of the IPCC (IPCC AR4) Working Group II (2007) identifies small island states as being among the most vulnerable countries of the world to the adverse impacts of climate change. Hay, el al.y (2003) in discussing the Pacific's observed climate noted that compared to earlier historical records during the twentieth century, the southern Pacific had experienced a significantly drier and warmer climate (by 15 percent and 0.8°C, respectively). The Central Equatorial Pacific is facing more intensive rain (about 30 percent) and a similarly hotter climate (0.6°C), and sea surface temperatures in both areas have increased by about 0.4°C. These conditions are linked to an increased frequency of El Nino episodes since the 1970s (without alternating La Nina events). Other studies show that climate projections for the South Pacific indicate warming of 0.8 to 1.8°C and precipitation changes that range from -8 to +7 percent by mid-century (Ruosteenoja, el ai, 2003). By the end of the century, projected warming is 1.0 to 3.1°C and precipitation changes range from -14 to +14 percent. Projections of globally averaged sea-level rise range from 0.18 m to 0.58 m in 2090-2099 relative to 1980-1999; while tropical cyclones are likely to become more intense, have higher peak wind speeds, and bring heavier rainfall (IPCC, 2007). Thus, it is clear that there are winners and losers when it comes to climate and food security with mostly the countries in the mid to higher latitudes benefiting from global warming and the small island countries of the Pacific in the warmer latitudes standing to lose the most. The IPCC has concluded that the mounting evidence shows that climate change is unequivocally happening and may worsen in future; there is a need to act urgently to minimize these impacts.