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Recent international agreements have strengthened and expanded commitments to protect and restore native habitats for biodiversity protection ("area‐based biodiversity conservation"). Nevertheless, biodiversity conservation is hindered because how such commitments should be implemented has been strongly debated, which can lead to suboptimal habitat protection decisions. We argue that, despite the debates, there are three essential principles for area‐based biodiversity conservation. These principles are related to habitat geographic coverage, amount, and connectivity. They emerge from evidence that, while large areas of nature are important and must be protected, conservation or restoration of multiple small habitat patches is also critical for global conservation, particularly in regions with high land use. We contend that the many area‐based conservation initiatives expected in the coming decades should follow the principles we identify, regardless of ongoing debates. Considering the importance of biodiversity for maintenance of ecosystem services, we suggest that this would bring widespread societal benefits. [ABSTRACT FROM AUTHOR]

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Species' traits have been widely championed as the key to predicting which species are most threatened by habitat loss, yet previous work has failed to detect trends that are consistent enough to guide large-scale conservation and management. Here we explore whether traits and environmental variables predict species sensitivity to habitat loss across two data sets generated by independent avifaunal studies in the Atlantic Forest of Brazil, both of which detected a similar assemblage of species, and similar species-specific responses to habitat change, across an overlapping sample of sites. Specifically, we tested whether 25 distributional, climatic, ecological, behavioral, and morphological variables predict sensitivity to habitat loss among 196 bird species, both within and across studies, and when data were analysed as occurrence or abundance. We found that four to nine variables showed high explanatory power within a single study or data set, but none performed as strong predictors across all data sets. Our results demonstrate that the use of species traits to predict sensitivity to anthropogenic habitat loss can produce predictions that are species- and site-specific and not scalable to whole regions or biomes, and thus should be used with caution. [ABSTRACT FROM AUTHOR]

Abstract: The search for surrogates of changes in species richness and community structure in fragmented landscapes involves not only the selection of predictors, such as landscape metrics or environmental variables, but also the identification of the spatial scale that is most relevant to the taxa in question. However the heavily intercorrelated nature of many structural features in fragmented landscapes complicates analyses, and the wide variation in species responses prevents the identification of a general trend. In this study, we used a two-tiered hierarchical variation partitioning to identify the unique and shared effects of: 1 – changes in vegetation structure at the plot scale, patch structure (size and shape), and forest cover at the landscape scale; and 2 – variables within these scales; as predictors of species richness and species’ abundances of birds in a fragmented landscape of Atlantic Forest; with the goal of aiding to the development of biodiversity indicators. Birds were sampled with mist-nets with a constant effort of 680 net-h at each of 23 sites, which resulted in almost 2600 captures. At the community level, regression models showed that changes in plot, patch and landscape scale variables explained a large proportion of the variation in species richness, but results from variation partitioning showed that the intercorrelation among predictors was so high that the unique contribution of each was non-significant. Our results point to a relatively large unique effect of local and landscape scale variables at the community level, but we also show that results vary greatly depending on the trophic guild being analysed. At the species level, multiple scale models also presented high explanatory power, however, species responses were so varied that we could not detect a general trend. We conclude that there is no single ‘best’ scale that could function as a proxy for changes in bird communities because each species and functional guild is uniquely affected by the environment, and suggest that efforts should be focused on finding indicators that encompasses all scales and the needs of different taxa. [Copyright &y& Elsevier]

There is now an extensive literature on extinction debt following deforestation. However, the potential for species credit in landscapes that have experienced a change from decreasing to expanding forest cover has received little attention. Both delayed responses should depend on current landscape forest cover and on species life-history traits, such as longevity, as short-lived species are likely to respond faster than long-lived species., We evaluated the effects of historical and present-day local forest cover on two vertebrate groups with different longevities - understorey birds and non-flying small mammals − in forest patches at three Atlantic Forest landscapes. Our work investigated how the probability of extinction debt and species credit varies (i) amongst landscapes with different proportions of forest cover and distinct trajectories of forest cover change, and (ii) between taxa with different life spans., Our results suggest that the existence of extinction debt and species credit, as well as the potential for their future payment and/or receipt, is not only related to forest cover trajectory but also to the amount of remaining forest cover at the landscape scale. Moreover, differences in bird and small mammal life spans seem to be insufficient to affect differently their probability of showing time-delayed responses to landscape change., Synthesis and applications. Our work highlights the need for considering not only the trajectory of deforestation/regeneration but also the amount of forest cover at landscape scale when investigating time-delayed responses to landscape change. As many landscapes are experiencing a change from decreasing to expanding forest cover, understanding the association of extinction and immigration processes, as well as their interactions with the landscape dynamic, is a key factor to plan conservation and restoration actions in human-altered landscapes. [ABSTRACT FROM AUTHOR]

Abstract Habitat loss is a primary threat to biodiversity across the planet, yet contentious debate has ensued on the importance of habitat fragmentation ‘per se’ (i.e., altered spatial configuration of habitat for a given amount of habitat loss). Based on a review of landscape-scale investigations, Fahrig (2017; Ecological responses to habitat fragmentation per se. Annual Review of Ecology, Evolution, and Systematics 48:1-23) reports that biodiversity responses to habitat fragmentation ‘per se’ are more often positive rather than negative and concludes that the widespread belief in negative fragmentation effects is a ‘zombie idea’. We show that Fahrig's conclusions are drawn from a narrow and potentially biased subset of available evidence, which ignore much of the observational, experimental and theoretical evidence for negative effects of altered habitat configuration. We therefore argue that Fahrig's conclusions should be interpreted cautiously as they could be misconstrued by policy makers and managers, and we provide six arguments why they should not be applied in conservation decision-making. Reconciling the scientific disagreement, and informing conservation more effectively, will require research that goes beyond statistical and correlative approaches. This includes a more prudent use of data and conceptual models that appropriately partition direct vs indirect influences of habitat loss and altered spatial configuration, and more clearly discriminate the mechanisms underpinning any changes. Incorporating these issues will deliver greater mechanistic understanding and more predictive power to address the conservation issues arising from habitat loss and fragmentation. Highlights • Habitat loss and fragmentation have long been considered to have negative effects on biodiversity. • Yet recent review by Fahrig (2017) argues that in fact habitat fragmentation has largely positive effects on biodiversity. • We highlight empirical and theoretical counter evidence that illustrate negative effects of fragmentation can be common. • We argue that positive effects can often be misleading or not of conservation importance. • We provide six key reasons why the conclusions in Fahrig (2017) should not be used in conservation decision-making. [ABSTRACT FROM AUTHOR]