Landscape connectivity

The population of Tiger (Panthera Tigris) in India has undergone
a sharp decline over the past few years.In the past, many protected
areas (PAs) have even seen their worst in terms of their tiger numbers.
One of such PA is Panna National Park, wherein the tiger population
literally came to 0 in 2009.in recent past, tigers from PTR have been found to be migrating to adjoining forest areas, travelling more than 100 km to reach different PA like Bandhavgarh. In order to provide them a safe passage between PTR and different PA,it’s critical that potential habitat be identified and that needs of tigers be incorporated in development plans of the region. This process requires incorporating the tiger landscape conservation strategy and action plan into the national and regional social and economic development plans.

Preserving avian flyway connectivity has long been challenged by our capacity to meaningfully quantify continental habitat dynamics and bird movements at temporal and spatial scales underlying long‐distance migrations. Waterbirds migrating hundreds or thousands of kilometers depend on networks of wetland stopover sites to rest and refuel. Entire populations may rely on discrete wetland habitats, particularly in arid landscapes where the loss of limited stopover options can have disproportionately high impacts on migratory cost. Here, we examine flyway connectivity in water‐limited ecosystems of western North America using 108 GPS tagged greater sandhill cranes. Bird movements were used to reconstruct wetland stopover networks across three geographically unique sub‐populations spanning 12 U.S.–Mexican states and Canadian provinces. Networks were monitored with remote sensing to identify long‐term (1988–2019) trends in wetland and agricultural resources supporting migration and evalua...

In recent years, ecological corridors have been proposed on a global scale as a response to the accelerated process of natural ecosystem fragmentation, mainly as a result of human impact. In accordance with this trend, Costa Rica has undergone a process of implementing ecological corridors as to promote ecological connectivity since the 1990s, with the establishment of 44 ecological corridors covering 38% of Costa Rica's territory. Nevertheless, there is no research evaluating these corridors on a national scale that takes into account their functions as conduits, barriers, and habitats. Thus, the objective of this research was to describe the process of biological corridor formation in Costa Rica, and to evaluate the potential effectiveness of corridors by considering aspects of landscape structure and ecological processes related to connectivity and fragmentation. We used the National Program of Ecological Corridors database along with coverage analysis from Landsat images fro...

Land-use and land-cover (LULC) changes are major drivers of biodiversity loss in semi-arid regions, such as the Caatinga biome located in the Northeast of Brazil. We investigated landscape dynamics and fragmentation in an area of the São Francisco Valley in the Brazilian Caatinga biome and measured the effect of these dynamics on ecological, functional and structural connectivity over a 33-year period (1985–2018). We calculated landscape connectivity indices based on graph theory to quantify the effect of further agricultural expansion on ecological connectivity at the landscape scale. We used a multicriteria decision analysis that integrates graph-based connectivity indices at the habitat patch scale, combined with an index of human disturbance to identify patches that, if conserved and restored, preserve the connectivity of the landscape most effectively. In the period studied, agriculture increased at a rate of 2104 ha/year, while native Caatinga vegetation decreased at a rate of...

Climate change, habitat loss and fragmentation, invasive species, and resource over-exploitation are among the major factors driving biodiversity loss and the current global change crisis. Maintaining and restoring connectivity throughout fragmented landscapes is key to reduce habitat isolation and mitigate anthropogenic impacts. To date, few connectivity approaches seek to identify corridors along climate gradients and least transformed natural habitats despite its importance to facilitate dispersal of organisms, as species' ranges shift over time to track suitable climates. In this study, we identified least-cost climatic corridors in Mexico between 2027 old-growth vegetation patches incorporating evapotranspiration as climatic variable, Euclidean distances, and human impact. We identified old-growth vegetation patches using the land use and vegetation map of 2011 (scale 1:250 000) by the National Institute of Statistics and Geography (INEGI). Moreover, we calculated a human i...

Context Habitat connectivity is key when designing reserve networks for conservation of species at risk. Acquiring land over time to achieve connectivity for multiple species in a systematic conservation plan can pose a challenge because not all high priority parcels will be acquired, species occurrence data is often limited, and using multiple species models together is complex. Objectives We evaluated four possible land acquisition strategies in a such a plan in their ability to meet each of three objectives. The strategies represent different combinations of what are termed ‘Priority 1’, ‘Priority 2’, and ‘Corridor’ lands in the plan. The objectives are to (1) meet conservation target acreages identified in the plan; these are distinct from connectivity goals, (2) maximize structural habitat connectivity, and (3) maximize connectivity for multiple focal species. Methods For this case study in Yolo County, California, we compared the efficiency of strategies to meet conservation t...

Dispersal of animals among populations helps to increase genetic variability and population viability. The endangered ocelot (Leopardus pardalis) in south Texas persists in two small populations separated by 30 km and cutoff from populations in northeastern Mexico. Despite the relatively short distance separating the two south Texas populations, movement between them has been limited, leading researchers to believe landscape connectivity is poor in the region. We developed habitat suitability maps using remote sensing and GPS‐collared ocelots and ran connectivity analyses to assess current habitat linkages, important areas for conservation, and areas where connectivity could be improved through habitat restoration. First, we developed a resource selection function using random forest models and GPS data from ten ocelots collared at Laguna Atascosa National Wildlife Refuge combined with spatial layers derived from LiDAR and remotely sensed imagery. We then used these results as the b...

While spatial accessibility characterises and identifies high-altitude mountain and protected areas in The Alps―monitoring the number of visitors is still largely grounded to the accommodation facilities and/or transport links in the bordering valleys/municipalities. The local spatial planning instruments which might permit a change in tourism bed-density as a key indicator, e.g., municipal space and landscape plans, have a fundamental impact on the surrounding near-natural areas. Yet, the pattern of the non-technical visitor flow (trails) in high-altitude areas is not fully monitored or analysed. In fact, several recent studies focus on the visitor counting methods utilised at observation-based points for the monitoring of tourism flow, i.e., visitor count per hour per point, without equally elaborating on methodology(ies) to identify these points―apart from a selection criteria. Thus, this paper addresses, quantifies and geo-visualises the question of: what points-of-eco/cultural-interest (POIs) of a mountain landscape are being consumed as a commodity―for the monitoring of tourism flow and multi-purpose impact surveys for policy-testing? The POIs are subjected to a profound temporality as a result of the change in landscape consumption, i.e., through the promotion of clusters of POIs. Founded on the cartographic theory and field landscape documentation surveys in Alto Adige/Südtirol (and The Alps), this paper introduces a cartographic and spatio-market planning methodology and indicator to answer the above question. It spatially segments the POIs in the high-altitude mountain and protected areas, based on accessibility and topography, and land cover and feature type (characteristics/geodiversity); and analyses the connectivity clusters of the POIs (preference). All destinations, i.e., nodes (ultimate POIs), within the boundary of a particular high-altitude mountain and protected area, are identified through cross-referencing all available sectoral/industry sources, where the total POIs on all possible routes to a specific node form a single preference (connectivity) cluster. The clusters overlap to create low/medium/high frequency POIs. Thus, the methodology funnels the landscape into a pattern of multiple frequency consumption POIs (quantification) of specific characteristics for the monitoring of tourism flow in actual market terms, and maps these preference (connectivity) clusters for use in local/regional spatial planning instrumentation (protected area and municipal plans), i.e., geodata tool (geo-visualisation). The methodology has formative and comparative implementation in high-altitude mountain and protected areas in The Alps, namely, with regards to conservation and area connectivity. The impact of visitors along the trails is assessed by an impact indicator, i.e., through the aggregation of the multiple frequency POIs into multiple frequency unit areas (localised grid). As an ultimate result, the indicator ‘Impact Density of Tourism Flow’, equals, the number of medium/high frequency unit areas per particular high-altitude area (total area). The geo-visualisation of this indicator act as a management tool to identify medium/high frequency unit areas for the monitoring tourism flow. The latter is mentioned in terms of unit areas not POIs―because within each of the unit areas there might be several medium/high frequency POIs, where only one POI (highest frequency) will be used as a monitoring point to avoid any visitor double-counts. Thus, the monitoring would occur based on both, the patterns of the POIs inside each unit area and the unit areas across a particular high-altitude mountain and protected areas―while factoring-in the geodiversity (characteristics) of the landscape as a unique offering identified at the POIs level (competitive advantage/economy of difference). The monitoring of tourism flow through the implementation of the spatio-market methodology  and the use of the indicator: ‘Impact Density of Tourism Flow’―directly facilitates the cooperation between the supralocal stakeholders: nature protection and tourism associations and businesses, municipalities, etc. The identified and quantified POIs and unit areas are associated with the Sustainable Tourism Management policy in the study-area, i.e., namely, nature conservation, beyond the approach based on the accommodation facilities and/or transport links in the bordering valleys/municipalities. Hence, nature conservation is 1 out 15 key issue areas addressed by the Sustainable Tourism Observatory of South Tyrol, part of the data-driven long-term UNWTO-INSTO International Network of Sustainable Tourism Observatories. Moreover, this policy is aligned with the AlpCon - Alpine Convention’s Tourism protocol, article 8 on Controlling Tourists Flows, particularly in protected areas, and AlpArc’s Alpine Park 2030, recommendation 10 on Direct and Concentrate Touristic Impact.

The Atlantic Forest of eastern Paraguay has experienced extensive recent deforestation. Less than one-third of the region is forested, and the remaining forest largely consists of isolated remnants with potentially disrupted connectivity for forest fauna. We used a graph theory approach to identify those forest remnants that are important in maintaining landscape structural connectivity for mammals in this fragmented forest. We quantified structural connectivity for forest remnants over the period 2000–2019 at three levels: the entire network of Atlantic Forest remnants in eastern Paraguay; at 10 smaller, nested spatial scales (40–10,000 m) encompassing a range of potential mammalian dispersal abilities; and at the level of individual remnants. We used 10 graph theory metrics to assess aspects of network complexity, dispersal-route efficiency, and individual remnant importance in supporting structural connectivity. We identified forest remnants that serve as important structural con...

Context The area-isolation paradigm of metapopulation theory predicts that larger and more connected patches have a higher probability of occupancy. Although it may be too simplistic for generalist terrestrial mammals, the area-isolation paradigm may be an effective tool for assessing patch-occupancy for habitat specialists. Objectives We tested predictions of the area-isolation paradigm for the endangered salt marsh harvest mouse (Reithrodontomys raviventris), a habitat specialist living in highly fragmented salt marsh habitat in the San Francisco Estuary (California, USA). Methods We surveyed for salt marsh harvest mice at 47 marsh patches throughout their range using a non-invasive genetic survey technique. We used occupancy modeling to estimate the effects of patch size, patch connectivity, matrix urbanization, and several habitat characteristics on occupancy probabilities. We evaluated occupancy at both coarse (e.g., among patches) and fine (e.g., within patches) spatial scales...

Marine protected areas (MPAs) are important conservation tools that can support the resilience of marine ecosystems. Many countries, including Canada, have committed to protecting at least 10% of their marine areas under the Convention on Biological Diversity's Aichi Target 11, which includes connectivity as a key aspect. Connectivity, the movement of individuals among habitats, can enhance population stability and resilience within and among MPAs. However, little is known about regional spatial patterns of marine ecological connectivity, particularly adult movement. We developed a method to assess and design MPA networks that maximize inferred connectivity within habitat types for adult movement when ecological data are limited. We used the Northern Shelf Bioregion in British Columbia, Canada, to explore two different approaches: (1) evaluating sites important for inferred regional connectivity (termed hotspots) and (2) assessing MPA network configurations based on their overla...

Understanding the spatial scale of population structure is fundamental to long-standing tenets of population biology, landscape ecology and conservation. Nonetheless, identifying such scales has been challenging because a key factor that influences scaling - movement among patches or local populations - is a multicausal process with substantial phenotypic and temporal variation. We resolve this problem via a novel application of network modularity. When applied to movements, modularity provides a formal description of the functional aggregation of populations and identifies potentially critical scales for ecological and evolutionary dynamics. We first test for modularity using several different types of biologically relevant movements across the entire geographic range of an endangered bird, the snail kite (Rostrhamus sociabilis plumbeus). We then ask whether variation in movement based on (i) age, (ii) sex and (iii) time (annual, seasonal and within-season movements) influences spa...