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Biodiversity offsets are commonly used to compensate for environmental impacts, but their effectiveness is often questioned. Estimations of expected losses and gains often rely on what we called condition metrics, which measure a site's quality or condition using certain ecological attributes. Condition metrics are central to most offset policies, but their attributes and calculations vary substantially. We reviewed the academic literature to draw a profile of existing condition metrics used in the offsetting context. We found 17 metrics that differed in how they included attributes from the three "dimensions of equivalence": biodiversity (present in 15 metrics), landscape (in 10 metrics) and ecosystem services (in 5 metrics). Most metrics included many ecological attributes and required fieldwork and GIS data to be calculated, but few used modeling and expert opinion. Generally, metrics aggregated the attributes into a single final value and were created in Global North countries. To favor more transparent and ecologically equivalent offset trades worldwide, we suggest condition metrics should include the three dimensions of equivalence in a disaggregated way, i.e. measurements done separately and analyzed in parallel. The use of modeling, expert opinion and GIS may facilitate the inclusion of the dimensions and reduce the need for intensive (and expensive) fieldwork. Testing synergies and trade-offs among attributes could indicate if metrics can be simplified without losing information. Finally, development of fit-for-purpose condition metrics is especially important in Global South countries, where few such metrics exist. [ABSTRACT FROM AUTHOR]

Monitoring is critical to gauge the effect of environmental management interventions as well as to measure the effects of human disturbances such as climate change. Recognition of the critical need for monitoring means that, at irregular intervals, recommendations are made for new government-instigated programs or to revamp existing ones. Using insights from past well-intentioned (but sadly also often failed) attempts to establish and maintain government-instigated monitoring programs in Australia, we outline eight things that should never be done in environmental monitoring programs (if they aim to be useful). These are the following: (1) Never commence a new environmental management initiative without also committing to a monitoring program. (2) Never start a monitoring program without clear questions. (3) Never implement a monitoring program without first doing a proper experimental design. (4) Never ignore the importance of matching the purpose and objectives of a monitoring program to the design of that program. (5) Never change the way you monitor something without ensuring new methods can be calibrated with the old ones. (6) Never try to monitor everything. (7) Never collect data without planning to curate and report on it. (8) If possible, avoid starting a monitoring program without the necessary resources secured. To balance our "nevers", we provide a checklist of actions that will increase the chances a monitoring program will actually measure the effectiveness of environmental management. Scientists and resource management practitioners need to be part of a stronger narrative for, and key participants in, well-designed, implemented, and maintained government-led monitoring programs. We argue that monitoring programs should be mandated in threatened species conservation programs and all new environmental management initiatives. [ABSTRACT FROM AUTHOR]

Humanity will soon define a new era for nature—one that seeks to transform decades of underwhelming responses to the global biodiversity crisis. Area-based conservation efforts, which include both protected areas and other effective area-based conservation measures, are likely to extend and diversify. However, persistent shortfalls in ecological representation and management effectiveness diminish the potential role of area-based conservation in stemming biodiversity loss. Here we show how the expansion of protected areas by national governments since 2010 has had limited success in increasing the coverage across different elements of biodiversity (ecoregions, 12,056 threatened species, 'Key Biodiversity Areas' and wilderness areas) and ecosystem services (productive fisheries, and carbon services on land and sea). To be more successful after 2020, area-based conservation must contribute more effectively to meeting global biodiversity goals—ranging from preventing extinctions to retaining the most-intact ecosystems—and must better collaborate with the many Indigenous peoples, community groups and private initiatives that are central to the successful conservation of biodiversity. The long-term success of area-based conservation requires parties to the Convention on Biological Diversity to secure adequate financing, plan for climate change and make biodiversity conservation a far stronger part of land, water and sea management policies. The long-term success of area-based conservation—including both protected areas and other effective area-based conservation measures—after 2020 will depend on governments securing adequate funding and prioritizing biodiversity in land, water and sea management. [ABSTRACT FROM AUTHOR]

Context: Understanding how landscape fragmentation affects functional diversity, defined as the distribution of functional traits in an assemblage, is critical for managing landscapes for biodiversity and ecosystem functions. Despite some scattered evidence, we lack a clear understanding of how patterns of fragmentation drive changes in functional diversity, and its relationship with species richness as habitat is lost from a landscape. Objectives: To develop testable predictions about how landscape fragmentation, relative to the effects of habitat loss, impacts functional diversity and its relationship with species richness. Methods: We used a spatially explicit metacommunity model that evaluates communities that vary in the distribution of response traits (traits involved in species responses to environmental change) and the correlation between response and effect traits (traits associated with species' effects on ecosystem functioning). Results: Compared to effects of habitat loss, relative effects of fragmentation on functional diversity increased as the variance in the distribution of response traits was high and the correlation among traits was high. Functional richness decreased faster than species richness in highly fragmented landscapes as habitat was lost. However, functional diversity remained unchanged or even increased in fragmented landscapes when either response and effect traits were not correlated (or weakly correlated), or when the proportion of generalist species with high dispersal capacities was high. Conclusions: Compared to effects of habitat loss, the relative effects of fragmentation on functional diversity and species richness are more dependent on the type of community evaluated. A careful evaluation of the variance in the distribution of response traits within a community, as well as the correlation among response and effect traits, can help to determine when it is important to manage landscape fragmentation to protect functional diversity. [ABSTRACT FROM AUTHOR]

Offsetting—trading losses in one place for commensurate gains in another—is a tool used to mitigate environmental impacts of development. Biodiversity and carbon are the most widely used targets of offsets; however, other ecosystem services are increasingly traded, introducing new risks to the environment and people. Here, we provide guidance on how to "trade with minimal trade-offs"— i.e. how to offset impacts on biodiversity without negatively affecting ecosystem services and vice versa. We briefly survey the literature on offsetting biodiversity, carbon and other ecosystem services, revealing that each subfield addresses unique issues (often overlooking those raised by others) and rarely assesses potential trade-offs. We discuss key differences between offsets that trade biodiversity and those that trade ecosystem services, conceptualise links between these different targets in an offsetting context and describe three broad approaches to manage potential trade-offs. We conclude by proposing a research agenda to strengthen the outcomes of offsetting policies that are emerging internationally. [ABSTRACT FROM AUTHOR]

Context: Native vegetation extent is often a proxy for habitat area in studies of human-modified landscapes. However, the loss and retention of native vegetation is rarely random among landscapes. Instead, the extent of native vegetation in landscapes may be correlated with abiotic factors, thereby obscuring or distorting relationships between ecological phenomena and area. Objectives: We asked: (1) how has the potential for non-random vegetation loss to confound area effects been addressed in the landscape ecology literature? (2) Are consistent patterns of non-random vegetation loss and retention evident from modified regions of two countries? Methods: We reviewed 118 papers that related area to an ecological response, to determine whether potential biases associated with non-random vegetation loss and retention were considered. We then analysed ~18,000 100 km landscape units in Australia and South Africa to identify how different abiotic factors correlate with the extent of native vegetation retained in those landscapes. Results: Only 21% of the studies we reviewed explicitly or implicitly considered spatial biases in vegetation clearing. Yet, across modified regions of Australia and South Africa, landscape-scale native vegetation extent was consistently and often strongly related to abiotic factors, particularly soil properties and topographic variability. Conclusion: Patterns of vegetation clearing and retention commonly reflect underlying abiotic heterogeneity. These biases, which are infrequently highlighted in studies focussing on area effects, have implications for how we assess the importance of vegetation extent for species and assemblages. Failure to account for correlates of vegetation extent risks erroneous area-based conservation prescriptions in human-modified environments. [ABSTRACT FROM AUTHOR]

Context: An increasing number of studies have investigated the impact of environmental heterogeneity on faunal assemblages when measured at multiple spatial scales. Few studies, however, have considered how the effects of heterogeneity on fauna vary with the spatial scale at which the response variable is characterised. Objectives: We investigated the relationship between landscape properties in a region characterised by diverse fire mosaics, and the structure and composition of avian assemblages measured at both the site- (1 ha) and landscape-scale (100 ha). Methods: We surveyed birds and calculated spatial landscape properties in sub-tropical woodlands of central Queensland, Australia. Results: Environmental heterogeneity, as measured by topographic complexity, was consistently important for bird species richness and composition. However, the explanatory power of topographic complexity varied depending on the spatial scale and the component of diversity under investigation. We found different correlates of richness within particular foraging guilds depending on the scale at which richness was measured. Extent of long-unburnt habitat (>10 years since fire) was the most important variable for the landscape-scale richness of frugivores, insectivores and canopy feeders, whereas environmental heterogeneity in the surrounding landscape was more important for site-scale richness of these foraging guilds. Conclusions: The response of species richness to landscape characteristics varies among scales, and among components of diversity. Thus, depending on the scale at which a biodiversity conservation goal is conceptualised-maximising richness at a site, or across a landscape-different landscape management approaches may be preferred. [ABSTRACT FROM AUTHOR]

Context: Fauna distributions are assessed using discrete (binary and mosaic) or continuous conceptualisations of the landscape. The value of the information derived from these analyses depends on the relevance of the landscape representation (or model) used to the landscape and fauna of interest. Discrete representations dominate analyses of landscape context in disturbed and regenerating landscapes; however within-patch variation suggests that continuous representations may help explain the distribution of fauna in such landscapes. Objectives: We tested the relevance of binary, mosaic, and continuous conceptualisations of landscape context to reptiles in regenerating dryland landscapes. Methods: For each of thirteen reptile groups, we compared the fit of models consisting of one landscape composition and one landscape heterogeneity variable for each of six landscape representations (2× binary, 2× mosaic, and 2× continuous), at three buffer distances. We used Akaike weights to assess the relative support for each model. Maps were created from Landsat satellite images. Results: Reptiles varied in their response to landscape context; however, the binary landscape representation with classes 'intact/disturbed' was best supported overall. Species richness was best described by a binary landscape representation with classes 'wooded/clear', whereas reptile abundance was best described by a mosaic landscape representation with classes defined by vegetation type. Five out of ten reptile species responded strongly to a single landscape representation, with the most relevant representation and conceptualisation varying among species. Conclusions: Our findings support the use of multiple landscape conceptualisations and representations during analyses of landscape context for fauna in regenerating landscapes. [ABSTRACT FROM AUTHOR]

Accounting for differences in abundances among species remains a high priority for community ecology. While there has been more than 80 years of work on trying to explain the characteristic S shape of rank-abundance distributions (RADs), there has been recent conjecture that the form may not depend on ecological processes per se but may be a general phenomenon arising in many unrelated disciplines. We show that the RAD shape can be influenced by an ecological process, namely, interference competition. The noisy miner ( Manorina melanocephala) is a hyperaggressive, 'despotic' bird that occurs over much of eastern Australia (>10km). We compiled data for bird communities from 350 locations within its range, which were collected using standard avian survey methods. We used hierarchical Bayesian models to show that the RAD shape was much altered when the abundance of the strong interactor exceeded a threshold density; RADs consistently were steeper when the density of the noisy miner ≥2.5 birds ha. The structure of bird communities at sites where the noisy miner exceeded this density was very different from that at sites where the densities fell below the threshold: species richness and Shannon diversity were much reduced, but mean abundances and mean avian biomass per site did not differ substantially. [ABSTRACT FROM AUTHOR]

Globally, modification of landscapes for agriculture has had a strong influence on the distribution and abundance of biota. In particular, woodland-dependent birds are under threat across agricultural landscapes in Britain, North America and Australia, with their decline and extirpation attributed to the loss and fragmentation of habitat. Other native species have become over-abundant in response to anthropogenic landscape change and have strong interactive effects on avian assemblage structure. In eastern Australia, the hyper-aggressive noisy miner ( Manorina melanocephala) often dominates woodlands in agricultural landscapes through interspecific competition, resulting in declines of species richness of woodland-dependent birds. We aimed to determine the relative influence and importance of interspecific competition, in situ habitat structure and landscape structure for woodland-dependent bird species at the landscape level. We recorded species-specific landscape incidence of woodland-dependent birds in 24 agricultural-woodland mosaics (25 km 2) in southern Queensland, Australia. We selected extensively cleared landscapes (10–23 % woodland cover) where fragmentation effects are expected to be greatest. We applied generalised linear models and hierarchical partitioning to quantify the relative importance of the landscape-level incidence of the noisy miner, mistletoe abundance, shrub cover, woodland extent, woodland subdivision and land-use intensity for the incidence of 46 species of woodland birds at the landscape-scale. The landscape-level incidence of the noisy miner was the most important explanatory variable across the assemblage. Both in situ habitat structure and landscape structure were of secondary importance to interspecific aggression, although previous research suggests that the increasing incidence of the noisy miner in fragmented agricultural landscapes is itself a consequence of anthropogenic changes to landscape structure. Species’ responses to fragmentation varied from positive to negative, but complex habitat structure had a consistently positive effect, suggesting in situ restoration of degraded habitats could be a conservation priority. Landscape wide conservation of woodland-dependent bird populations in agricultural landscapes may be more effective if direct management of noisy miner populations is employed, given the strong negative influence of this species on the incidence of woodland-dependent birds among landscapes. [ABSTRACT FROM AUTHOR]

The identification of environmental factors linked to increased risk of local extinction often relies on inference from patterns of distribution. Yet for declining populations, the assumption of population equilibrium that underlies species distribution models is violated. Measures such as individual condition can provide a more direct indication of extinction risk, and can start to be detected before declines commence. We compared distribution-based and condition-based approaches to identifying factors affecting habitat suitability for an area-sensitive passerine, the eastern yellow robin Eopsaltria australis, in eastern Australia. We compared patterns of individual condition between robins and several common, more mobile species (Meliphagid honeyeaters and yellow thornbills Acanthiza nana). Robin presence was not affected by landscape context, but robins avoided sites with a more grassy ground layer. However, robins inhabiting landscapes with less remnant woodland had higher ratios of heterophils to lymphocytes in peripheral blood, indicating higher long-term stress. No clear spatial patterns of condition were detected for the more mobile species. Our findings suggest a hierarchical model of habitat suitability, whereby robins avoid grassy sites, but where they do occur are in poorest condition when inhabiting less-vegetated landscapes. We predict greater rates of local extinction of robins from such landscapes. The use of indicators of individual condition, in addition to distribution data, can unveil otherwise cryptic factors as important influences on habitat quality. As habitat occupancy does not always reflect habitat quality, exploring patterns in condition indices can complement species distribution modelling, potentially revealing threats to persistence before population declines have commenced. [ABSTRACT FROM AUTHOR]

The need to understand how anthropogenic landscape alteration affects fauna populations has never been more pressing. The importance of developing an understanding of the processes behind local extinction is widely acknowledged, but inference from spatial patterns of fauna distribution continues to dominate. However, this approach is limited in its ability to generate strong predictions about future distributions and local extinctions, especially when population-level responses to landscape alteration are subject to long time lags. We review the potential for indices of physiological stress and condition to contribute to understanding of how landscape pattern affects species persistence. Such measures can indicate habitat quality from the perspective of the individual animal, and can reveal environmental stressors before their negative consequences begin to manifest at a population level. Spatial patterns of chronic stress may therefore yield valuable insight into how landscape alteration influences species. We propose that the emerging disciplines of conservation physiology and macrophysiology have much to offer spatial ecology, and have great potential to reveal the physiological pathways through which habitat alteration affects fauna populations and their persistence in fragmented landscapes. [ABSTRACT FROM AUTHOR]

The need to avert unacceptable and irreversible environmental change is the most urgent challenge facing society. Landscape ecology has the capacity to help address these challenges by providing spatially-explicit solutions to landscape sustainability problems. However, despite a large body of research, the real impact of landscape ecology on sustainable landscape management and planning is still limited. In this paper, we first outline a typology of landscape sustainability problems which serves to guide landscape ecologists in the problem-solving process. We then outline a formal problem-solving approach, whereby landscape ecologists can better bring about disciplinary integration, a consideration of multiple landscape functions over long time scales, and a focus on decision making. This framework explicitly considers multiple ecological objectives and socio-economic constraints, the spatial allocation of scarce resources to address these objectives, and the timing of the implementation of management actions. It aims to make explicit the problem-solving objectives, management options and the system understanding required to make sustainable landscape planning decisions. We propose that by adopting a more problem-solving approach, landscape ecologists can make a significant contribution towards realising sustainable future landscapes. [ABSTRACT FROM AUTHOR]

The authors state that governments should not use compensation that developers pay for damaging biodiversity to meet existing environmental conservation targets such as those under the Convention on Biological Diversity. They comment on biodiversity offsetting schemes which usually try to achieve no net loss of biodiversity and mention the schemes don't always end biodiversity loss but may instead offset existing losses. They suggest offset-funded protected areas should be tallied separately.

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]