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Landscape context can affect how individuals perceive patch quality during colonization. However, although context-dependent colonization has been observed in aquatic environments it has rarely been studied in terrestrial environments or at large spatial scales. Here, we assessed how landscape context influenced colonization rates in a large-scale (ca 7000 km2) terrestrial system where colonizers (Willow Warbler Phylloscopus trochilus) are capable of rapid, long-distance movements. Bioacoustic recorders were used to detect first song dates (an indicator of colonization or re-colonization) and settlement in 23 naturally replicated habitat patches. We compared support for three competing hypotheses describing colonization patterns that depend on landscape context (‘redirection’, ‘landscape-selection’ and ‘relative patch size’) with two patch-level hypotheses (patch ‘quality’ and ‘heterospecific attraction’). First song was earlier when habitat availability in the landscape was low, supporting the ‘redirection’ hypothesis. Settlement probability was best predicted by patch ‘quality’ and was lower in woodlands with a dense understorey. Results suggest that colonization of habitat patches by male P. trochilus after spring migration is spatially hierarchical. First, initial colonization depends on landscape context, and settlement is then determined by fine-scale vegetation characteristics. More broadly, we suggest that patterns observed in fragmented aquatic environments (e.g. ‘redirection’) can, in some circumstances, be extended to large-scale terrestrial environments.

It is important for conservationists to be able to assess the risks that climate change poses to species, in order to inform decision making. Using standardised and repeatable methods, we present a national-scale assessment of the risks of range loss and opportunities for range expansion that climate change could pose for over 3000 plants and animals. Species were selected by their occurrence in England, the primary focus of the study, but climate change impacts were assessed across Great Britain, widening their geographical relevance. A basic risk assessment that compared projected future changes in potential range with recently observed changes classified 21% of species as being at high risk and 6% at medium risk of range loss under a B1 climate change scenario. A greater number of species were classified as having a medium (16%) or high (38%) opportunity to potentially expand their distribution. A more comprehensive assessment, incorporating additional ecological information, including potentially confounding and exacerbating factors (e.g. dispersal, habitat availability and other constraints), was applied to 402 species, of which 35% were at risk of range loss and 42% may expand their range extent. This study covers a temperate region with a significant proportion of species at their poleward range limit; the balance of risks and opportunities from climate change may be different elsewhere. The outcome of both risk assessments varied between taxonomic groups, with bryophytes and vascular plants containing the greatest proportion of species at risk from climate change. Upland habitats contained more species at risk than other habitats. Whilst the overall pattern was clear, confidence was generally low for individual assessments, with the exception of well-studied taxa such as birds. In response to climate change, nature conservation needs to plan for changing species distributions and an uncertain future.

There has been a growing interest across the British conservation community in recent years in establishing conservation over large areas. Much of this thinking was crystallised in the Making Space for Nature report (Lawton and others 2010) , and has since become prominent in conservation policy. To maximise the success of future projects, there is a need to get a better overview of the many large-scale conservation (LSC) initiatives that already exist, and to investigate what can be learned from past experience. To date there has been no thorough study of the scope, spatial extent, management and planning approaches and effectiveness of LSC. This report summarises the results of a research study that provides the first comprehensive review of large-scale conservation initiatives in England, Scotland and Wales. The study was made up of a series of linked research projects with funding and support from Defra, Natural England, Scottish Natural Heritage and Natural Resources Wales and was carried out by the University of Southampton, University of Cambridge, Natural England and Atkins.

Natural experiments have been proposed as a way of complementing manipulative experiments to improve ecological understanding and guide management. There is a pressing need for evidence from such studies to inform a shift to landscape-scale conservation, including the design of ecological networks. Although this shift has been widely embraced by conservation communities worldwide, the empirical evidence is limited and equivocal, and may be limiting effective conservation. We present principles for well-designed natural experiments to inform landscape-scale conservation and outline how they are being applied in the WrEN project, which is studying the effects of 160years of woodland creation on biodiversity in UK landscapes. We describe the study areas and outline the systematic process used to select suitable historical woodland creation sites based on key site- and landscape-scale variables – including size, age, and proximity to other woodland. We present the results of an analysis to explore variation in these variables across sites to test their suitability as a basis for a natural experiment. Our results confirm that this landscape satisfies the principles we have identified and provides an ideal study system for a long-term, large-scale natural experiment to explore how woodland biodiversity is affected by different site and landscape attributes. The WrEN sites are now being surveyed for a wide selection of species that are likely to respond differently to site- and landscape-scale attributes and at different spatial and temporal scales. The results from WrEN will help develop detailed recommendations to guide landscape-scale conservation, including the design of ecological networks. We also believe that the approach presented demonstrates the wider utility of well-designed natural experiments to improve our understanding of ecological systems and inform policy and practice.