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Islands are global hotspots of both biodiversity and extinction. Invasive species are a primary threat, and the majority of islands have been invaded by more than one. Multispecies eradications are essential for conserving the biodiversity of these islands, but experience has shown that eradicating species at the wrong time can be disastrous for endemic species., Managers not only have to decide how to eradicate each invasive species, they need to determine when to target each species, and how to control multiple species with a limited budget. We use dynamic control theory to show that, when resources are limited, species should be eradicated in a particular order (an eradication schedule). We focus on a common invaded island ecosystem motif, where one invasive predator consumes two prey species (one endemic, one invasive), and managers wish to eradicate both invasives while ensuring the persistence of the endemic species. We identify the optimal eradication schedule for this entire class of problem. To illustrate the application of our solution, we also analyse a particular case study from California's Channel Islands., For any island ecosystem that shares this motif, managers should begin by allocating all of their resources towards invasive predator control. Only later should resources be shifted towards controlling the invasive prey. This shift should ideally be gradual, but an abrupt shift is very close to optimal. The Channel Islands case study confirms these findings. Targeting both species simultaneously is substantially suboptimal., We reach the robust conclusion that the same eradication schedule should be applied to any island with this ecosystem motif, even if the ecosystem contains different species to the Channel Islands case study., Synthesis and applications. Although very numerous, the world's invaded island ecosystems could be described by a limited range of invaded ecosystem motifs. By calculating robust optimal eradication schedules for each motif, the approach defined in this study could offer rapid decision-support for a large number of future conservation projects where specific data are scarce. [ABSTRACT FROM AUTHOR]

Much of conservation planning has focused on how we should prioritize areas for protection based on biodiversity and cost, but less is known about how we should prioritize areas based upon the level of threat they face. We discuss two opposing threat prioritization strategies: frontier conservation (prioritizing high‐threat areas) and wilderness conservation (prioritizing low‐threat areas). Using a temporally explicit model, we demonstrate that the best strategy depends on a variety of factors, including protection costs, heterogeneity in biodiversity, biodiversity–area relationships, the rate of biodiversity recovery, the rate of change in threats through time, and the timeframe within which we measure conservation outcomes. By quantitatively comparing the impact of these strategies, we aim to shift the debate away from a simple dichotomy of frontier versus wilderness, toward an understanding of the context‐specific benefits of each option, and a discussion of how threat combines with other factors to determine spatial conservation priorities. [ABSTRACT FROM AUTHOR]

Abstract: Payments to private landholders for providing biodiversity land can improve conservation outside protected areas. Input‐based payments are widely used despite evidence they are often ineffective at improving biodiversity outcomes. Meanwhile, little has been done to assess how to use outcome‐based payments to maximize biodiversity, despite growing academic interest. We compare different outcome‐based allocation methods to assess which returns the greatest benefits for biodiversity. We predicted the likely landholder actions in response to outcome‐based payments. We incorporated strategic interactions between landholders under four different funding allocation methods: the commonly applied “set‐price” allocation method; capacity‐based payments; proportional payment; and payment for change. We compared biodiversity outcomes (percentage change in abundance of a species of conservation interest), return on investment and cost‐effectiveness of each method. The set‐price allocation method, despite its common usage, is the least cost‐effective method that we test. Regardless of cost, it only results in better biodiversity outcomes than other methods under a very narrow range of conditions (high initial target species abundance and low profitability). The profitability of the property, and to a lesser degree initial population size, will influence which allocation method will perform best. Most perform well when the initial population of the species of conservation interest is very small and profitability negligible. Only one method—based on change in population—performs well across all scenarios. This method outperforms the others particularly when the property has a higher profitability and low initial numbers of animals. Policy implications. Pursuing conservation on private land using outcome‐based payments for biodiversity can result in varied levels of success depending on the allocation methods used to support payment decisions. Allocation method choice should be based on a transparent analysis that incorporates both the dynamics of the ecological system and interactions between individual landholders. This analysis can guide adoption of funding allocation methods that greatly increase biodiversity outcomes. [ABSTRACT FROM AUTHOR]

Decision-makers increasingly use life-cycle assessment ( LCA) as a tool to measure the environmental sustainability of products. LCA is of particular importance in globalized agricultural supply chains, which have environmental effects in multiple and spatially dispersed locations., Incorporation of impacts on biodiversity that arise from agricultural production systems into environmental assessment methods is an emerging area of work in LCA, and current approaches have limitations, including the need for (i) improved assessment of impacts to biodiversity associated with agricultural production, (ii) inclusion of new biodiversity indicators (e.g. conservation value, functional diversity, ecosystem services) and (iii) inclusion of previously unaccounted modelling variables that go beyond land-use impacts (e.g. climate change, water and soil quality)., Synthesis and applications. Ecological models and understanding can contribute to address the limitations of current life-cycle assessment (LCA) methods in agricultural production systems and to make them more ecologically relevant. This will be necessary to ensure that biodiversity is not neglected in decision-making that relies on LCA. [ABSTRACT FROM AUTHOR]