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Habitat loss and climate change are key drivers of global biodiversity declines but their relative importance has rarely been examined. We attempted to attribute spatially divergent population trends of two Afro‐Palaearctic migrant warbler species, Willow Warbler Phylloscopus trochilus and Common Chiffchaff Phylloscopus collybita, to changes in breeding grounds climate or habitat. We used bird counts from over 4000 sites across the UK between 1994 and 2017, monitored as part of the BTO/JNCC/RSPB Breeding Bird Survey. We modelled Willow Warbler and Common Chiffchaff population size and growth in relation to habitat, climate and weather. We then used the abundance model coefficients and observed environmental changes to determine the extent to which spatially varying population trends in England and Scotland were consistent with attribution to climate and habitat changes. Both species' population size and growth correlated with habitat, climate and weather on their breeding grounds. Changes in habitat, in particular woodland expansion, could be linked to small population increases for both species in England and Scotland. Both species' populations correlated more strongly with climate than weather, and both had an optimum breeding season temperature: 11°C for Willow Warbler and around 13.5°C for Common Chiffchaff (with marginally different predictions from population size and growth models). Breeding ground temperature increases, therefore, had the potential to have caused some of the observed Willow Warbler declines in England (where the mean breeding season temperature was 12.7°C) and increases in Scotland (mean breeding season temperature was 10.2°C), and some of the differential rates of increase for Common Chiffchaff. However, much of the variation in species' population abundance and trends were not well predicted by our models and could be due to other factors, such as species interactions, habitat and climate change in their wintering grounds and on migration. This study provides evidence that the effect of climate change on a species may vary spatially and may switch from being beneficial to being detrimental if a temperature threshold is exceeded. [ABSTRACT FROM AUTHOR]

Empirical evidence from many regions suggests that most species would be least negatively affected if human food demand were met through high‐yield agricultural production and conservation of nonfarm ecosystems (land sparing), rather than through wildlife‐friendly farming over a larger area (land sharing). However, repeated glaciation and a long history of agriculture may lead to different results in regions such as western Europe. We compared the consequences of land sparing and land sharing on breeding bird species in 2 lowland regions of England, The Fens, with 101 species, and Salisbury Plain, with 83. We derived density–yield responses for each species and then estimated regional population size under regional food production strategies, including land sharing and land sparing, a range of intermediate strategies, and a novel mixed strategy. In both regions, more species achieved maximum regional population size under land sparing than land sharing. In The Fens, the majority of birds were loser species (estimated to have smaller populations under all food production strategies than in the preagricultural baseline scenario), whereas in Salisbury Plain the majority were winners (smaller populations in the preagricultural baseline scenario). Loser species overwhelmingly achieved maximum regional population size under land sparing, whereas winner species achieved maximum regional population size under either land sharing or an intermediate strategy, highlighting the importance of defining which groups of species are the target of conservation. A novel 3‐compartment strategy (combining high‐yield farming, natural habitat, and low‐yield farming) often performed better than either land sharing or land sparing. Our results support intermediate or 3‐compartment land‐sparing strategies to maximize bird populations across lowland agricultural landscapes. To deliver conservation outcomes, any shift toward land sparing must, however, ensure yield increases are sustainable in the long term, do not entail increased negative effects on surrounding areas, and are linked to allocation of land for nature. Article impact statement: By freeing up land for conservation, high‐yield farming can maximize biodiversity outcomes even in long‐converted landscapes. [ABSTRACT FROM AUTHOR]

The article presents a research which examines the relationships between indicators of riverine water and associated freshwater biodiversity, habitat quality, and terrestrial biodiversity across Wales and England. Results show the strong associations between the indicators of freshwater services and biodiversity of species. It is inferred that relationships between indicators of services change depending on the societal pressures and other regional conditions.

In human-dominated regions, protected areas are complemented by other conservation strategies (e.g., restrictive zoning, incentive payments) to maintain biodiversity and other ecosystem services. These strategies are often not mutually exclusive, with many areas covered by multiple (tiered) management strategies. However, it is not known whether tiering increases (or decreases) representation of ecosystem services. Here, we compare the representation of four ecosystem services by areas protected by both tiered and single conservation strategies (protected areas, restrictive zoning, and incentive payments to landowners) in a human-dominated region (England). Tiering always coincided with the highest levels of stored carbon, sometimes coincided with high biodiversity and agricultural production, but never coincided with high recreational value. We also show that tiering is common in England and biased towards upland areas. Future evaluations of the effectiveness of conservation strategies should consider the degree of overlap of the different strategies fully to understand which are most effective. [ABSTRACT FROM AUTHOR]

1. An increasing number of studies are examining the distribution and congruence of ecosystem services, often with the goal of identifying areas that will provide multiple ecosystem service ‘hotspots’. However, there is a paucity of data on most ecosystem services, so proxies (e.g. estimates of a service for a particular land cover type) are frequently used to map their distribution. To date, there has been little attempt to quantify the effects of using proxies on distribution maps of ecosystem services, despite the potentially large errors associated with such data sets. 2. Here, we provide the first study examining the effects of using proxies on ecosystem service maps and the degree of spatial congruence of these maps with primary data, using England as a case study. 3. We show that land cover based proxies provide a poor fit to primary data surfaces for biodiversity, recreation and carbon storage, and that correlations between ecosystem services change depending on whether primary or proxy data are used for the analyses. 4. The poor fit of proxies to primary data was also evident when we selected hotspots of single ecosystem services, and consistency between raw and modelled surfaces was extremely low when considering the locations that were coincident hotspots for multiple services. 5. Synthesis and applications. Proxies may be suitable for identifying broad-scale trends in ecosystem services, but even relatively good proxies are likely to be unsuitable for identifying hotspots or priority areas for multiple services. [ABSTRACT FROM AUTHOR]

Aim: This paper describes the development of novel indices of bird-habitat preference to examine bird species' use of habitats and their distributions relative to habitats. It assesses the implications for bird conservation regionally and the scope for biodiversity assessments generally. Location: A 200 km by 400 km area of farmland with seminatural and urban areas, covering south-eastern England. Methods: Cluster analysis was used to link birds to landscapes. Cluster centroid coordinate values were processed to derive indices of bird-habitat preference. Further developments assessed the relative values of individual habitats for birds. Results: Clustering objectively linked birds to landscapes. Maps of the clusters showed strong regional patterns associated with distinctive habitat assemblages. Derived indices related bird species directly to individual habitats and habitats to birds. Even rare species and scarce habitats showed successful linkages, often to each other. Objective corroboration strongly supported the associations of coastal, wetland, urban and woodland birds and habitats; but, it suggested that farmland birds, whose numbers have nearly halved since 1977, may prefer alternative habitats. Main conclusions: Land cover maps from remote sensing provide an effective way to link birds to habitats and vice versa. Thus, generalized habitat maps might be used to extrapolate localized or sample-based bird observations or the results of autecological studies, helping to predict and understand bird distributions in the wider countryside. The weak links between farmland birds and farmland habitats in a region dominated by farming, suggests that reasons for the decline in farmland birds may be deep seated and thus hard to reverse. The procedures described are repeatable elsewhere and applicable more generally to evaluate landscapes and biodiversity. It is suggested that remote sensing could rarely be bettered as a means of assessing habitats, comprehensively, over wide areas, in most parts of the world. [ABSTRACT FROM AUTHOR]