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Conserving or restoring landscape connectivity between patches of breeding habitat is a common strategy to protect threatened species from habitat fragmentation. By managing connectivity for some species, usually charismatic vertebrates, it is often assumed that these species will serve as conservation umbrellas for other species. We tested this assumption by developing a quantitative method to measure overlap in dispersal habitat of 3 threatened species-a bird (the umbrella), a butterfly, and a frog-inhabiting the same fragmented landscape. Dispersal habitat was determined with Circuitscape, which was parameterized with movement data collected for each species. Despite differences in natural history and breeding habitat, we found substantial overlap in the spatial distributions of areas important for dispersal of this suite of taxa. However, the intuitive umbrella species (the bird) did not have the highest overlap with other species in terms of the areas that supported connectivity. Nevertheless, we contend that when there are no irreconcilable differences between the dispersal habitats of species that cohabitate on the landscape, managing for umbrella species can help conserve or restore connectivity simultaneously for multiple threatened species with different habitat requirements. Definición y Evaluación del Concepto de Especie Paraguas para Conservar y Restaurar la Conectividad de Paisajes [ABSTRACT FROM AUTHOR]

Balancing ecological and social outcomes of conservation actions is recognized in global conservation policy but is challenging in practice. Compensation to land owners or users for foregone assets has been proposed by economists as an efficient way to mitigate negative social impacts of human displacement from protected areas. Joint empirical assessments of the conservation and social impacts of protected area establishment involving compensation payments are scarce. We synthesized social and biological studies related to the establishment of the Derema forest corridor in Tanzania's biodiverse East Usambara Mountains. This lengthy conservation process involved the appropriation of approximately 960 ha of native canopy agroforest and steep slopes for the corridor and monetary compensation to more than 1100 claimants in the surrounding villages. The overarching goals from the outset were to conserve ecological processes while doing no harm to the local communities. We evaluated whether these goals were achieved by analyzing 3 indicators of success: enhancement of forest connectivity, improvement of forest condition, and mitigation of negative impacts on local people's livelihoods. Indicators of forest connectivity and conditions were enhanced through reductions of forest loss and exotic species and increases in native species and canopy closure. Despite great efforts by national and international organizations, the intervention failed to mitigate livelihood losses especially among the poorest people. The Derema case illustrates the challenges of designing and implementing compensation schemes for conservation-related displacement of people. Resultados Ecológicos y Sociales de un Área Protegida Nueva en Tanzania [ABSTRACT FROM AUTHOR]

Habitat linkages can help maintain connectivity of animal populations in developed landscapes. However, the lack of empirical data on the width of lateral movements (i.e., the zigzagging of individuals as they move from one point to point another) makes determining the width of such linkages challenging. We used radiotracking data from wood frogs (Lithobates sylvaticus) and spotted salamanders (Ambystoma maculatum) in a managed forest in Maine (U.S.A.) to characterize movement patterns of populations and thus inform planning for the width of wildlife corridors. For each individual, we calculated the polar coordinates of all locations, estimated the vector sum of the polar coordinates, and measured the distance from each location to the vector sum. By fitting a Gaussian distribution over a histogram of these distances, we created a population-level probability density function and estimated the 50th and 95th percentiles to determine the width of lateral movement as individuals progressed from the pond to upland habitat. For spotted salamanders 50% of lateral movements were ≤13 m wide and 95% of movements were ≤39 m wide. For wood frogs, 50% of lateral movements were ≤17 m wide and 95% of movements were ≤ 51 m wide. For both species, those individuals that traveled the farthest from the pond also displayed the greatest lateral movement. Our results serve as a foundation for spatially explicit conservation planning for pond-breeding amphibians in areas undergoing development. Our technique can also be applied to movement data from other taxa to aid in designing habitat linkages. Caracterización de la Amplitud de Movimiento de Anfibios durante la Migración Pos-Reproducción [ABSTRACT FROM AUTHOR]

As habitat loss and fragmentation threaten biodiversity on large geographic scales, creating and maintaining connectivity of wildlife populations is an increasingly common conservation objective. To assess the progress and success of large-scale connectivity planning, conservation researchers need a set of plans that cover large geographic areas and can be analyzed as a single data set. The state wildlife action plans (SWAPs) fulfill these requirements. We examined 50 SWAPs to determine the extent to which wildlife connectivity planning, via linkages, is emphasized nationally. We defined linkage as connective land that enables wildlife movement. For our content analysis, we identified and quantified 6 keywords and 7 content criteria that ranged in specificity and were related to linkages for wide-ranging terrestrial vertebrates and examined relations between content criteria and statewide data on focal wide-ranging species, spending, revenue, and conserved land. Our results reflect nationwide disparities in linkage conservation priorities and highlight the continued need for wildlife linkage planning. Only 30% or less of the 50 SWAPs fulfilled highly specific content criteria (e.g., identifying geographic areas for linkage placement or management). We found positive correlations between our content criteria and statewide data on percent conserved land, total focal species, and spending on parks and recreation. We supplemented our content analysis with interviews with 17 conservation professionals to gain specific information about state-specific context and future directions of linkage conservation. Based on our results, relevant literature, and interview responses, we suggest the following best practices for wildlife linkage conservation plans: collect ecologically meaningful background data; be specific; establish community-wide partnerships; and incorporate sociopolitical and socioeconomic information. Acercamientos a la Conectividad de Vida Silvestre y las Mejores Prácticas en los Planes de Acción de Vida Silvestre Estatales en los Estados Unidos [ABSTRACT FROM AUTHOR]

Although the concept of connectivity is decades old, it remains poorly understood and defined, and some argue that habitat quality and area should take precedence in conservation planning instead. However, fragmented landscapes are often characterized by linear features that are inherently connected, such as streams and hedgerows. For these, both representation and connectivity targets may be met with little effect on the cost, area, or quality of the reserve network. We assessed how connectivity approaches affect planning outcomes for linear habitat networks by using the stock-route network of Australia as a case study. With the objective of representing vegetation communities across the network at a minimal cost, we ran scenarios with a range of representation targets (10%, 30%, 50%, and 70%) and used 3 approaches to account for connectivity (boundary length modifier, Euclidean distance, and landscape-value [LV]). We found that decisions regarding the target and connectivity approach used affected the spatial allocation of reserve systems. At targets ≥50%, networks designed with the Euclidean distance and LV approaches consisted of a greater number of small reserves. Hence, by maximizing both representation and connectivity, these networks compromised on larger contiguous areas. However, targets this high are rarely used in real-world conservation planning. Approaches for incorporating connectivity into the planning of linear reserve networks that account for both the spatial arrangement of reserves and the characteristics of the intervening matrix highlight important sections that link the landscape and that may otherwise be overlooked. El Efecto de la Planeación para la Conectividad en Redes de Reservas Lineales [ABSTRACT FROM AUTHOR]

Ecological edges are increasingly recognized as drivers of landscape patterns and ecosystem processes. In fragmented and patchy landscapes (e.g., a fragmented forest or a savanna with scattered termite mounds), edges can become so numerous that their effects pervade the entire landscape. Results of recent studies in such landscapes show that edge effects can be altered by the presence or proximity of other nearby edges. We considered the theoretical significance of edge-effect interactions, illustrated various landscape configurations that support them and reviewed existing research on this topic. Results of studies from a variety of locations and ecosystem types show that edge-effect interactions can have significant consequences for ecosystems and conservation, including higher tree mortality rates in tropical rainforest fragments, reduced bird densities in grassland fragments, and bush encroachment and reduced wildlife densities in a tropical savanna. To clarify this underappreciated concept and synthesize existing work, we devised a conceptual framework for edge-effect interactions. We first worked to reduce terminological confusion by clarifying differences among terms such as edge intersection and edge interaction . For cases in which nearby edge effects interact, we proposed three possible forms of interaction: strengthening (presence of a second edge causes stronger edge effects), weakening (presence of a second edge causes weaker edge effects), and emergent (edge effects change completely in the presence of a second edge). By clarifying terms and concepts, this framework enables more precise descriptions of edge-effect interactions and facilitates comparisons of results among disparate study systems and response variables. A better understanding of edge-effect interactions will pave the way for more appropriate modeling, conservation, and management in complex landscapes. Interacciones del Efecto de Borde en Paisajes Fragmentados [ABSTRACT FROM AUTHOR]

Centrality metrics evaluate paths between all possible pairwise combinations of sites on a landscape to rank the contribution of each site to facilitating ecological flows across the network of sites. Computational advances now allow application of centrality metrics to landscapes represented as continuous gradients of habitat quality. This avoids the binary classification of landscapes into patch and matrix required by patch-based graph analyses of connectivity. It also avoids the focus on delineating paths between individual pairs of core areas characteristic of most corridor- or linkage-mapping methods of connectivity analysis. Conservation of regional habitat connectivity has the potential to facilitate recovery of the gray wolf (Canis lupus), a species currently recolonizing portions of its historic range in the western United States. We applied 3 contrasting linkage-mapping methods (shortest path, current flow, and minimum-cost-maximum-flow) to spatial data representing wolf habitat to analyze connectivity between wolf populations in central Idaho and Yellowstone National Park (Wyoming). We then applied 3 analogous betweenness centrality metrics to analyze connectivity of wolf habitat throughout the northwestern United States and southwestern Canada to determine where it might be possible to facilitate range expansion and interpopulation dispersal. We developed software to facilitate application of centrality metrics. Shortest-path betweenness centrality identified a minimal network of linkages analogous to those identified by least-cost-path corridor mapping. Current flow and minimum-cost-maximum-flow betweenness centrality identified diffuse networks that included alternative linkages, which will allow greater flexibility in planning. Minimum-cost-maximum-flow betweenness centrality, by integrating both land cost and habitat capacity, allows connectivity to be considered within planning processes that seek to maximize species protection at minimum cost. Centrality analysis is relevant to conservation and landscape genetics at a range of spatial extents, but it may be most broadly applicable within single- and multispecies planning efforts to conserve regional habitat connectivity. [ABSTRACT FROM AUTHOR]

Conservation researchers are increasingly aware of the need to conduct interdisciplinary research and to engage nonscientists in practical applications of conservation biology. But so far, industrial designers have been left out of such collaboration and outreach efforts. Conservation of wildlife often depends on products such as nest boxes, feeders, barriers, and corridors, all of which have a designed component that is frequently overlooked. Furthermore, many products are adopted without testing on short or long time scales. We argue that the design of products for conservation, and hence their functionality, effectiveness, and value, can be improved through collaboration with industrial designers. We see four key benefits that can arise from interactions with industrial designers: improvement of product quality and value, innovation and improvement in functionality of products, harmonization of conservation products with local values, and development of a psychological biomimesis approach to design. The role of industrial designers in conservation projects would be to improve factors such as product durability, affordability, functionality, and aesthetic appeal to local people. Designers can also help to create multiple product options whose success can be tested in the field. We propose that collaborations with industrial designers can contribute to the development of improvements to existing products and innovations in the practice of animal conservation. [ABSTRACT FROM AUTHOR]

To counteract habitat fragmentation, the connectivity of a landscape should be enhanced. Corridors are thought to facilitate movement between disconnected patches of habitat, and linear strips of habitat connecting isolated patches are a popular type of corridor. On the other hand, the creation of new corridors can lead to fragmentation of the surrounding habitat. For example, heathland corridors connect patches of heathland and alternatively hedgerows connect patches of woodland. Nevertheless, these corridors themselves also break up previously connected patches of their surrounding habitat and in so doing fragment another type of habitat (heathland corridors fragment woodlands and woodland strips or hedgerows fragment heathlands). To overcome this challenge we propose the use of semi-open habitats (a mixture of heathland and woodland vegetation) as conservation corridors to enable dispersal of both stenotopic heathland and woodland species. We used two semi-open corridors with a mosaic of heathland and woody vegetation to investigate the efficiency of semi-open corridors for species dispersal and to assess whether these corridors might be a suitable approach for nature conservation. We conducted a mark-recapture study on three stenotopic flightless carabid beetles of heathlands and woodlands and took an inventory of all the carabid species in two semi-open corridors. Both methodological approaches showed simultaneous immigration of woodland and heathland species in the semi-open corridor. Detrended correspondence analysis showed a clear separation of the given habitats and affirmed that semi-open corridors are a good strategy for connecting woodlands and heathlands. The best means of creating and preserving semi-open corridors is probably through extensive grazing. [ABSTRACT FROM AUTHOR]

The ability of populations to be connected across large landscapes via dispersal is critical to long-term viability for many species. One means to mitigate population isolation is the protection of movement corridors among habitat patches. Nevertheless, the utility of small, narrow, linear features as habitat corridors has been hotly debated. Here, we argue that analysis of movement across continuously resistant landscapes allows a shift to a broader consideration of how landscape patterns influence connectivity at scales relevant to conservation. We further argue that this change in scale and definition of the connectivity problem improves one's ability to find solutions and may help resolve long-standing disputes regarding scale and definition of movement corridors and their importance to population connectivity. We used a new method that combines empirically derived landscape-resistance maps and least-cost path analysis between multiple source and destination locations to assess habitat isolation and identify corridors and barriers to organism movement. Specifically, we used a genetically based landscape resistance model for American black bears ( ) to identify major movement corridors and barriers to population connectivity between Yellowstone National Park and the Canadian border. Even though western Montana and northern Idaho contain abundant public lands and the largest wilderness areas in the contiguous United States, moving from the Canadian border to Yellowstone Park along those paths indicated by modeled gene flow required bears to cross at least 6 potential barriers. Our methods are generic and can be applied to virtually any species for which reliable maps of landscape resistance can be developed. [ABSTRACT FROM AUTHOR]

The establishment of biological corridors between two otherwise isolated habitat patches is a common yet contentious strategy for conserving populations in fragmented landscapes. We compared the effectiveness of corridors with the effectiveness of an alternate conservation strategy, the enlargement of existing habitat patches. We used a spatially explicit population model that simulated population size in two kinds of patches. One patch had a corridor that connected it to a larger “source” patch and the other patch was unconnected and enlarged at the periphery by an area the same size as the corridor. Patch isolation, corridor width, patch size, and the probability that individuals would cross the border from habitat to matrix were varied independently. In general, population size was greater in enlarged patches than in connected patches when patches were relatively large and isolated. Corridor width and the probability of crossing the border from habitat to matrix did not affect the relative benefit of corridors versus patch enlargement. Although biological corridors may mitigate potential effects of inbreeding depression at long time scales, our results suggest that they are not always the best method of conserving fragmented populations. [ABSTRACT FROM AUTHOR]

Forest-associated species in fragmented landscapes must traverse potentially inhospitable gaps to move between habitat patches. Although conservation biologists advocate connecting patches with corridors or improving the matrix to make it suitable for movement, little is known about the factors influencing gap-crossing decisions for most species. We investigated gap crossing by the red squirrel ( ) in logged landscapes in southeastern Alaska, where the species avoids microhabitats associated with gaps created by clearcutting. We released individuals across clearcuts and determined the routes they took home with tracking spools and radio telemetry. Of 36 adult red squirrels translocated across six clearcuts, 14 crossed clearcuts to reach home. Squirrels were more likely to cross clearcuts if the detour efficiency (distance to home crossing gap divided by distance of forested detour) was low, indicating an ability to compare distances along alternate routes and travel costs or risks in different habitats. No other landscape metrics, such as gap size or crossing distance, predicted crossing behavior. Red squirrels of low body mass were more likely to cross clearcuts, where the probability of encountering conspecifics is low. Distance predicted route choice for squirrels detouring around clearcuts. Indirect evidence suggests that perceived predation risk, energetic costs, or both are higher in clearcuts. Detour efficiency reportedly influences the gap-crossing decisions of some forest-associated birds, but this is the first demonstration of its role in gap-crossing decisions by a mammal. [ABSTRACT FROM AUTHOR]