Connectivity In Conservation Planning Research Articles

The role of connectivity in conservation planning for species with obligatory interactions: Prospects for future climate scenarios

AbstractClimate change may lead to range shifts, and barriers to such displacements may result in extirpations from previously suitable habitats. This may be particularly important in freshwater ecosystems that are highly fragmented by anthropogenic obstacles, such as dams and other smaller in‐stream barriers. Conservation planning in freshwaters should consider the dynamic effects of climate change and the ability of species to cope with it. In this study, we developed a framework for incorporating climate‐driven dispersal barriers into conservation planning taking into account the medium and long‐term impacts of climate change and species with obligatory interactions. Given that freshwater mussels (Bivalvia: Unionida) are a group of highly threatened organisms dependent on fish hosts to complete their larval development and dispersal, we used Marxan to prioritize areas for their joint conservation in the Iberian Peninsula as a case study. We tested two connectivity scenarios between current and future habitats, (i) unlimited dispersal capacity and (ii) dispersal constrained by artificial barriers, and also identified priority translocation areas for species that were unable to disperse. Accounting for the effects of climate change on species distributions allowed the identification of long‐term conservation areas, but disregarding artificial barriers to dispersal may lead to unrealistic solutions. Integrating the location of barriers allowed the identification of priority areas that are more likely to be colonized in the future following climatic shifts, although this resulted in an additional loss of six to eight features (~5%–7%) compared to solutions without dispersal constraints. Between 173 and 357 artificial barriers (~1.6%–3.3%) will potentially block species dispersal to irreplaceable planning units. Where removal of artificial barriers is unfeasible, conservation translocations may additionally cover up to eight additional features that do not meet conservation targets due to dispersal constraints. This study highlights the challenge of identifying protected areas to safeguard biodiversity under climate change.

Supporting the planning of urban blue-green infrastructure for biodiversity: A multi-scale prioritisation framework

Primary considerations for urban blue-green infrastructure (BGI) encompass sustainable stormwater/urban heat management while biodiversity conservation is often considered an inherent benefit rather than a core planning requirement. However, ecological function of BGI as ‘stepping stones’ or linear corridors for otherwise fragmented habitats is undisputed. While quantitative approaches for modelling ecological connectivity in conservation planning are well established, mismatches in scope and scale with models that support the planning of BGI makes their adoption and integration difficult across disciplines. Technical complexities have led to ambiguity around circuit and network-based approaches, focal node placement, spatial extents, and resolution. Furthermore, these approaches are often computationally intensive, and considerable gaps remain in their use for identifying local-scale critical “pinch-points” that urban planners may respond to with the integration of BGI interventions that address biodiversity enhancement among other ecosystem services. Here, we present a framework that simplifies and integrates the merits of regional connectivity assessments with a focus on urban areas to prioritise BGI planning interventions while reducing computational demands. Our framework facilitates: (1) modelling potential ecological corridors at a coarse regional scale, (2) prioritising local-scale BGI interventions based on the relative contribution of individual nodes in this regional network, and (3) inferring connectivity hot- and cold-spots for local-scale BGI interventions. We illustrate this in the Swiss lowlands, demonstrating how, compared to previous work, we are able to identify and rank different priority locations across the region for BGI interventions in support of biodiversity enhancement and how their local-scale functional design may be benefited by addressing specific environmental variables.

The Potentials for the Ecological Management of Landscape Connectivity Including Aquatic Ecosystems in Northeast Albania

At the landscape level, freshwater ecosystems are linked at various spatial and temporal scales by movements of different fauna components adapted to life in water. We review the literature on the state of landscape connectivity and related aquatic species that connect different types of freshwater habitats, focusing on linkages from streams, large rivers and standing water bodies. Based on existing evidence, it is clear that biotic linkages throughout current mosaic have important consequences for biological integrity and biodiversity. The recent developments with regard to urbanization, expansion of urban centers, infrastructure development, and hydropower plant construction in Albania are in line with global destruction and fragmentation of habitats resulting in the parceling up of landscapes that, in this very case, have been caused by human population growth and development activities. The primary aim of this article is to address the landscape connectivity in a wider northeastern part of Albania considering various protected areas. The landscape connectivity is a pillar component of connectivity conservation that has emerged as a response approach to a range of threats to biodiversity, which include habitat degradation and destruction, fragmentation and climate changes. The approach analyses of landscape connectivity were defined from a human perspective in a linkage among different protected areas, including National Park Albanian Alps, Nature Park Korrab-Koritnik, National Park ShebenikJabllanica, Pogradec Landscape Protected Areas and National Park Prespa. The basis of this analysis lies in the Network of Protected Areas (NPAs) of Albania. Cumulatively, the protected areas connectivity, aquatic ecosystem linkage and individual movements connect populations within and among landscape mosaics and contribute to national and regional diversity and resilience to disturbance. This study highlights the importance of considering both terrestrial and aquatic ecosystems connectivity in conservation planning and management.

Conventional methods for enhancing connectivity in conservation planning do not always maintain gene flow

Abstract Protected area systems need to conserve species in places with suitable habitat that are configured to facilitate gene flow. Since genetic data require considerable resources to obtain, many proxy methods have been developed to generate plans for protected area systems (prioritizations) that facilitate gene flow without needing genetic data. However, the effectiveness of such methods—such as minimising fragmentation or enforcing contiguity among priority areas—remains largely untested. We investigated the ability of prioritizations to maintain gene flow when they are generated using conventional methods for promoting connectivity. Using existing environmental, genetic, and occurrence datasets, we created maps of habitat suitability and resistance to gene flow for nine alpine plant species. Next, we generated multispecies prioritizations that secured 10% of the suitable habitat for each species and attempted to maintain gene flow by (a) penalizing fragmentation, (b) representing species in contiguous areas of suitable habitat, and (c) representing species in contiguous areas with minimal resistance to gene flow as modelled from genetic data. We found that prioritizations generated using fragmentation penalties failed to represent seven of the nine species in areas that would maintain high levels of gene flow. Similarly, prioritizations that represented species in contiguous areas of suitable habitat were unable to maintain high levels of gene flow for six species—potentially because a few areas with high resistance can disrupt gene flow throughout an entire prioritization. Although prioritizations generated using genetic data successfully maintained gene flow, they also selected over three times more land than other prioritizations, suggesting that failing to account for gene flow when setting priorities may underestimate the scale of conservation action required. Synthesis and applications. We found that conventional methods for enhancing connectivity in conservation planning, such as spatially clustering priority areas or providing connected sections of suitable habitat, were generally unable to maintain high levels of gene flow. Our results suggest that conservation plans could be substantially improved by directly using genetic data, although whether this is a good choice for a particular situation will also depend on the costs of obtaining these data.

Using water residency time to enhance spatio‐temporal connectivity for conservation planning in seasonally dynamic freshwater ecosystems

SummaryAddressing spatial connectivity in conservation planning is important to ensure the maintenance of patterns and processes needed to support the persistence of biodiversity. In freshwater ecosystems, spatial connectivity is constrained by the presence of water, which exhibits marked temporal changes in regions with wet–dry seasonal climates. Previous studies have focused on spatial connectivity and overlooked the temporal component, which is required for the functionality of spatial connections (because of temporal changes in water availability).We identify priority areas for the conservation of freshwater fish, waterbirds and turtles in theMitchellRiver catchment in the wet–dry tropics of northernAustralia. We demonstrate how adequacy of freshwater conservation can be enhanced by integrating an estimate of water residency time (WRT) into the prioritization process.WRTreflects refugial potential and connectivity in freshwater ecosystems and was quantified usingModerateResolutionImagingSpectroradiometer (MODIS) flood and post‐floodLandsat satellite imagery. We compare the spatial allocation of priority areas and the spatial and temporal connectivity under two alternative scenarios: (i) accounting only for spatial connectivity and (ii) integrating spatial and temporal connectivity.Priority areas identified under the spatial and temporal connectivity scenario showed a 40% increase inWRTvalues with respect to the traditional spatial connectivity scenario. This was achieved at no additional cost in terms of total protected area and maintaining the same spatial connectivity.Despite priority areas identified under the two alternative scenarios showing intermediate spatial overlap (64%), the selection process was more efficiently biased towards planning units with highWRTvalues.WRTin planning units that were only selected under the temporal connectivity scenario was 2·5 times higher than in planning units that only appeared in the traditional connectivity scenario. This reveals the importance of accounting forWRTwhen identifying freshwater priority areas in wet–dry seasonal environments.Synthesis and applications: Considering the temporal connectivity in conservation prioritization as we propose here helps to assess periods of longest spatial connections, thereby maximizing the refugial role of freshwater priority areas during dry periods. Using publicly available satellite imagery data and software, our approach allows improved management of aquatic resources and biodiversity during periods of water scarcity, which may increase in incidence and duration with climate change.

LQGraph: A software package for optimizing connectivity in conservation planning

LQGraph implements methods for optimizing the connectivity of sites administered to protect biodiversity (a conservation area network). The methods are suitable for existing protected areas (for example, national parks) or a proposed network. We model the landscape using graphs. The user provides a quality score for each site in the landscape outside the conservation areas. Based on these scores, LQGraph finds contiguity areas of maximum quality to link the conservation areas. The contiguity areas can be filtered to prioritize those that connect the conservation areas with the minimum number of sites or area. Compared with existing methods for establishing connectivity in a conservation area network, LQGraph can analyze substantially larger networks. LQGraph also identifies sites that efficiently isolate conservation areas, which is useful for halting the spread of pathogens or invasive species. The software provides routines for constructing the required input files and for visualizing several properties of the landscape, including site quality and the shortest paths between conservation areas. LQGraph and the accompanying documentation can be freely downloaded from the worldwide web.

Ranging behaviour of greater flamingos during the breeding and post-breeding periods: Linking connectivity to biological processes

Connectivity among habitat patches has mainly been studied in relation to species-specific behaviours. However, the movements of animals among patches may have different functions, and tolerance to gaps between habitat patches may vary between these functions. We tracked the movements of greater flamingos during the breeding and post-breeding periods with the aim of illustrating how the degree of connectivity may vary depending on the biological processes underlying the movements between wetlands. Most foraging sites used by breeding adults in a colony in southern Spain were within 200 km of the colony site, although some birds eventually moved 400 km. After the breeding season, the adults remained for several weeks in specific wetlands, moving to other sites located 280–2100 km away to overwinter. During these movements the birds may use stopover sites, the conservation of which may be critical to facilitate long-range movements. Our results suggest that wetland connectivity during chick rearing does not seem to be determined by whether or not central-place foraging flamingos are able to reach wetlands located at the longest distance that they are able to fly during non-stop flights (>1000 km), but by whether they are able to sustain the energetic costs derived from frequent commuting. In contrast, long-distance movements were occasionally undertaken during the post-breeding period. The energetic costs of such flights could be paid by flamingos because these movements were infrequent. Thus, in the case of flamingos, connectedness thresholds between wetlands vary depending on the biological process involved (chick rearing or post-breeding movements). This emphasizes the need to consider different types of connectivity in conservation planning.