Empirical studies and habitat suitability modeling project significant shifts in species distributions in response to climate change. Because habitat fragmentation can impede species range shifts, ...wildlife corridors may have increasing importance in enhancing climate resilience for species persistence. While habitat connectivity has been studied for over four decades, the design of connectivity specifically to facilitate species movement in response to climate change is a relatively new challenge. We conducted a systematic review of 116 relevant papers from 1996-2017. Research focused on assessing the utility of habitat connectivity for climate change adaptation by species (N = 29) and modeling and mapping climate-wise connectivity for planning purposes (N = 55). Others addressed fundamental questions of connectivity related to climate adaptation (N = 31). Based on empirical data and computer simulations examining species range shifts in response to climate change at leading edges of current distributions; it is clear that large protected areas connected through linkages, and stepping stones embedded in a permeable matrix promote population persistence and facilitate range expansion. We identified 13 approaches to modeling climate-wise connectivity based on either focal species or landscape structure. When prioritizing areas for connectivity conservation, approaches include focusing on connecting areas of low climate velocity, refugia, climate analogs, or linking current to future suitable habitats. Riparian corridors should be considered in connectivity plans because of their importance as natural movement corridors, climate gradients, and refugia. Guidance is provided on selecting the best methods for connectivity design depending on the objectives, available data, and landscape context. Future research needs to evaluate the functionality of climate-wise connectivity models for facilitating range shifts and compare connectivity outcomes across modeling approaches.
Applied Wildlife Habitat Management  is an introductory textbook presenting principle management concepts and techniques. It supplies undergraduates and practitioners with the basic tools to ...understand, plan, implement, measure, analyze, and document their efforts to enhance habitat for wildlife on both private and public lands. Providing a step-by-step guide that is adaptable to a range of environmental settings, the authors first lay out the ecological principles applicable to any project. They then take the reader through the various sampling designs, measurement techniques, and basic analytical methods required to develop and complete a habitat project, including the creation of a report or management plan. This practical guide will be a valuable resource for professional biologists at the state and federal level, students and professors of conservation biology as well as natural resource agencies, NGOs, and private landowners.
Anthropogenic impacts have reduced natural areas but increased the area of anthropogenic landscapes. There is debate about whether anthropogenic landscapes (e.g., farmlands, orchards, and fish ponds) ...provide alternatives to natural habitat and under what circumstances. We considered whether anthropogenic landscapes can mitigate population declines for waterbirds. We collected data on population trends and biological traits of 1203 populations of 579 species across the planet. Using Bayesian generalized linear mixed models, we tested whether the ability of a species to use an anthropogenic landscape can predict population trends of waterbird globally and of species of conservation concern. Anthropogenic landscapes benefited population maintenance of common but not less‐common species. Conversely, the use of anthropogenic landscapes was associated with population declines for threatened species. Our findings delineate some limitations to the ability of anthropogenic landscapes to mitigate population declines, suggesting that the maintenance of global waterbird populations depends on protecting remaining natural areas and improving the habitat quality in anthropogenic landscapes.
Article impact statement: Protecting natural areas and improving the quality of anthropogenic landscapes as habitat are both needed to achieve effective conservation.
Efectos de los Paisajes Antropogénicos sobre la Conservación de Poblaciones de Aves Acuáticas
Resumen
Los impactos antropogénicos han reducido las áreas naturales, pero han incrementado el área de los paisajes antropogénicos. Existe un debate sobre si los paisajes antropogénicos (p. ej.: campos de cultivo, huertos, estanques de peces) proporcionan alternativas al hábitat natural y bajo cuáles circunstancias. Consideramos si los paisajes antropogénicos pueden mitigar las declinaciones poblacionales de las aves acuáticas. Recolectamos datos sobre las tendencias poblacionales y las características biológicas de 1203 poblaciones de 579 especies de aves de todo el mundo. Mediante modelos bayesianos generalizados lineales mixtos, analizamos si la habilidad de una especie para usar un paisaje antropogénico puede pronosticar las tendencias poblacionales de las aves acuáticas a nivel mundial y de las especies de interés para la conservación. Los paisajes antropogénicos beneficiaron a la conservación de las poblaciones de especies comunes, pero no para las especies menos comunes. Por otro lado, el uso de paisajes antropogénicos estuvo asociado con las declinaciones poblacionales en las especies amenazadas. Nuestros descubrimientos delinean algunas limitaciones que tienen los paisajes antropogénicos para mitigar las declinaciones poblacionales, lo que sugiere que la conservación mundial de las poblaciones de aves acuáticas depende de la protección de las áreas naturales remanentes y del mejoramiento de la calidad del hábitat en los paisajes antropogénicos.
人工景观对水鸟种群维持的影响
人类活动导致自然景观的面积不断减少而人工景观的面积不断增加。关于人工景观 (例如农田、果园、鱼塘) 能否为野生生物提供替代自然景观的栖息地, 以及在什么情况下可以提供适宜的栖息地, 目前仍存在争论。我们收集了全球 579 种水鸟 1203 个种群的数量变化趋势和生物学特性数据, 探讨了水鸟利用人工景观是否有助于其维持种群数量。利用贝叶斯广义线性混合模型, 我们分别针对全球水鸟和受胁水鸟检验了物种是否利用人工景观与其种群趋势的关系。利用人工景观有助于数量较多的常见种的种群维持, 但对数量较少的不常见种的种群维持没有显著影响。相反, 利用人工景观的受胁物种更倾向于表现出种群下降的趋势。本研究结果指出了人工景观在减缓种群数量下降方面存在一定局限性, 表明了维持全球水鸟种群稳定不仅需要保护自然景观, 而且需要改善人工景观的栖息地质量.
1. Climate and land-use changes will require species to move large distances following shifts in their suitable habitats, which will frequently involve traversing intensively human-modified ...landscapes. Practitioners will therefore need to evaluate and act to enhance the degree to which habitat patches scattered throughout the landscape may function as stepping stones facilitating dispersal among otherwise isolated habitat areas. 2. We formulate a new generalized network model of habitat connectivity that accounts for the number of dispersing individuals and for long-distance dispersal processes across generations. By doing so, we bridge the gap between complex dynamic population models, which are generally too data demanding and hence difficult to apply in practical wide-scale decision-making, and simpler static connectivity models that only consider the amount of habitat that can be reached by a single average disperser during its life span. 3. We find that the loss of intermediate and sufficiently large stepping-stone habitat patches can cause a sharp decline in the distance that can be traversed by species (critical spatial thresholds) that cannot be effectively compensated by other factors previously regarded as crucial for long-distance dispersal (fat-tailed dispersal kernels, source population size). 4. We corroborate our findings by showing that our model largely outperforms previous connectivity models in explaining the large-scale range expansion of a forest bird species, the Black Woodpecker Dryocopus martius, over a 20-year period. 5. The capacity of species to exploit the opportunities created by networks of stepping-stone patches largely depends on species-specific life-history traits, suggesting that species assemblages traversing fragmented landscapes may be exposed to a spatial filtering process driving long-term changes in community composition. 6. Synthesis and applications. Previous static connectivity models seriously underestimate the importance of stepping-stone patches in sustaining rare but crucial dispersal events. We provide a conceptually broader model that shows that stepping stones (i) must be of sufficient size to be of conservation value, (ii) are particularly crucial for the spread of species (either native or invasive) or genotypes over long distances and (iii) can effectively reduce the isolation of the largest habitat blocks in reserves, therefore largely contributing to species persistence across wide spatial and temporal scales.
1. Habitat suitability models are usually produced using species presence or habitat selection, without taking into account the demographic performance of the population considered. These models ...cannot distinguish between sink and source habitats, causing problems especially for species with low reproductive rates and high susceptibility to low levels of mortality as in the case of the critically endangered Apennine brown bear Ursus arctos marsicanus. 2. We developed a spatial model based on bear presence (2544 locations) and mortality data (37 locations) used as proxies for demographic performance. We integrated an occurrence and a mortality-risk Ecological Niche Factor Analysis model into a final two-dimensional model that can be used to distinguish between attractive sink-like and source-like habitat. 3. Our integrated model indicates that a traditional habitat suitability model can provide misleading management and conservation indications, as 43% of the area suitable for the occurrence model is associated with high mortality risk. Areas of source-like habitat for the Apennine bears (highly elevated areas rich in beech forests, far from roads, and with low human density and cultivated fields) are still present, including outside the currently occupied range. However, attractive sink-like habitat (associated with high levels of pasture, low extent of mountain meadows, low steepness, low elevation, and closeness to secondary and urban roads) are present even inside protected areas. 4. Synthesis and applications. Identifying attractive sink-like habitat is crucial to prevent inappropriate management and to effectively address conservation issues: whereas existing source-like habitats should be preserved to halt habitat loss and degradation, attractive sink-like habitat should be managed to mitigate mortality risks or to decrease their attractiveness. In particular, area-specific management interventions and proactive actions (increased patrolling, road closure, human activity management, threat monitoring, etc.) aimed at reducing human-caused mortality are critical for the Apennine brown bear.
Eastern spotted skunk (Spilogale putorius) populations have declined throughout much of their range in the eastern United States over recent decades. Declines have been attributed to habitat loss or ...change, increased competition with sympatric mesocarnivore species, or disease. To better understand the extant distribution of spotted skunks in the Appalachian Mountains of western Virginia, USA, we used a detection-non-detection sampling approach using baited camera traps to evaluate the influence of landscape-level environmental covariates on spotted skunk detection probability and site occupancy. We conducted camera trap surveys at 91 sites from January to May in 2014 and 2015. Spotted skunk occupancy was associated with young-aged forest stands at lower elevations and more mature forest stands at higher elevations. Both land cover types in this region can be characterized as having complex forest structure, providing cover that varies with stand age, species composition, elevation, and management regime. Our results provide insight into factors that influence spotted skunk spatial distribution and habitat selection, information that can be used to generate conservation assessments and inform management decisions.
ABSTRACT
Many wetlands harbour highly diverse biological communities and provide extensive ecosystem services; however, these important ecological features are being altered, degraded and destroyed ...around the world. Despite a wealth of research on how animals respond to anthropogenic changes to natural wetlands and how they use created wetlands, we lack a broad synthesis of these data. While some altered wetlands may provide vital habitat, others could pose a considerable risk to wildlife. This risk will be heightened if such wetlands are ecological traps – preferred habitats that confer lower fitness than another available habitat. Wetlands functioning as ecological traps could decrease both local and regional population persistence, and ultimately lead to extinctions. Most studies have examined how animals respond to changes in environmental conditions by measuring responses at the community and population levels, but studying ecological traps requires information on fitness and habitat preferences. Our current lack of knowledge of individual‐level responses may therefore limit our capacity to manage wetland ecosystems effectively since ecological traps require different management practices to mitigate potential consequences.
We conducted a global meta‐analysis to characterise how animals respond to four key drivers of wetland alteration: agriculture, mining, restoration and urbanisation. Our overarching goal was to evaluate the ecological impacts of human alterations to wetland ecosystems, as well as identify current knowledge gaps that limit both the current understanding of these responses and effective wetland management. We extracted 1799 taxon‐specific response ratios from 271 studies across 29 countries. Community‐ (e.g. richness) and population‐level (e.g. density) measures within altered wetlands were largely comparable to those within reference wetlands. By contrast, individual fitness measures (e.g. survival) were often lower, highlighting the potential limitations of using only community‐ and population‐level measures to assess habitat quality. Only four studies provided habitat‐preference data, preventing investigation of the potential for altered wetlands to function as ecological traps. This is concerning because attempts to identify ecological traps may detect previously unidentified conservation risks. Although there was considerable variability amongst taxa, amphibians were typically the most sensitive taxon, and thus, may be a valuable bio‐indicator of wetland quality. Despite suffering reduced survival and reproduction, measures such as time to and mass at metamorphosis were similar between altered and reference wetlands, suggesting that quantifying metamorphosis‐related measures in isolation may not provide accurate information on habitat quality.
Our review provides the most detailed evaluation to date of the ecological impacts of human alterations to wetland ecosystems. We emphasise that the role of wetlands in human‐altered ecosystems can be complex, as they may represent important habitat but also pose potential risks to animals. Reduced availability of natural wetlands is increasing the importance of altered wetlands for aquatic animals. Consequently, we need to define what represents habitat quality from the perspective of animals, and gain a greater understanding of the underlying mechanisms of habitat selection and how these factors could be manipulated. Furthermore, strategies to enhance the quality of these wetlands should be implemented to maximise their conservation potential.
"Conservation Biology in Sub-Saharan Africa comprehensively explores the challenges and potential solutions to key conservation issues in Sub-Saharan Africa. Easy to read, this lucid and accessible ...textbook includes fifteen chapters that cover a full range of conservation topics, including threats to biodiversity, environmental laws, and protected areas management, as well as related topics such as sustainability, poverty, and human-wildlife conflict. This rich resource also includes a background discussion of what conservation biology is, a wide range of theoretical approaches to the subject, and concrete examples of conservation practice in specific African contexts. Strategies are outlined to protect biodiversity whilst promoting economic development in the region. Boxes covering specific themes written by scientists who live and work throughout the region are included in each chapter, together with recommended readings and suggested discussion topics. Each chapter also includes an extensive bibliography. Conservation Biology in Sub-Saharan Africa provides the most up-to-date study in the field. It is an essential resource, available on-line without charge, for undergraduate and graduate students, as well as a handy guide for professionals working to stop the rapid loss of biodiversity in Sub-Saharan Africa and elsewhere. "
Abstract
Forest management and planning efforts often account for many resource objectives and benefits, including wildlife habitat. In particular, newly approved management goals and harvest targets ...on state lands in Minnesota were examined for their potential impact on wildlife habitat. Using a list of stands planned for potential harvest and a regional wildlife habitat model, habitat effects were assessed for 173 native, forest-dependent wildlife species on state lands. Leveraging forest type– and region-specific harvest probabilities and post-examination lag times to harvest, three simulation efforts covering the spectrum of possible outcomes were used to estimate habitat change from 2020 to 2030. In the most realistic simulation, 31.8% of species exhibited statistically significant positive habitat change, 11.6% significant negative change, and 56.6% nonsignificant or no change. Compared with simulations reflecting more extreme levels of harvest, the realistic simulation showed the greatest compromise between negative and positive shifts in habitat. Results reflect tradeoffs in wildlife habitat preferences such that changes in management that positively affect certain species often negatively affect others. Tradeoffs may be addressed by providing flexibility to individual managers where a targeted prescription is justified for a specific species, all while continuing broad statewide forest management goals.
Connectivity of habitat patches is thought to be important for movement of genes, individuals, populations, and species over multiple temporal and spatial scales. We used graph theory to characterize ...multiple aspects of landscape connectivity in a habitat network in the North Carolina Piedmont (U.S.A).. We compared this landscape with simulated networks with known topology, resistance to disturbance, and rate of movement. We introduced graph measures such as compartmentalization and clustering, which can be used to identify locations on the landscape that may be especially resilient to human development or areas that may be most suitable for conservation. Our analyses indicated that for songbirds the Piedmont habitat network was well connected. Furthermore, the habitat network had commonalities with planar networks, which exhibit slow movement, and scale-free networks, which are resistant to random disturbances. These results suggest that connectivity in the habitat network was high enough to prevent the negative consequences of isolation but not so high as to allow rapid spread of disease. Our graph-theory framework provided insight into regional and emergent global network properties in an intuitive and visual way and allowed us to make inferences about rates and paths of species movements and vulnerability to disturbance. This approach can be applied easily to assessing habitat connectivity in any fragmented or patchy landscape.
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