The Experts below are selected from a list of 8118 Experts worldwide ranked by ideXlab platform
Hugh P. Possingham - One of the best experts on this subject based on the ideXlab platform.
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trade offs between data resolution accuracy and cost when choosing information to plan Reserves for coral reef ecosystems
2017Co-Authors: Vivitskaia J D Tulloch, Ayesha I T Tulloch, Chris Roelfsema, Carissa J Klein, Stacy D Jupiter, Hugh P. PossinghamAbstract:Conservation planners must reconcile trade-offs associated with using biodiversity data of differing qualities to make decisions. Coarse habitat classifications are commonly used as surrogates to design marine Reserve Networks when fine-scale biodiversity data are incomplete or unavailable. Although finely-classified habitat maps provide more detail, they may have more misclassification errors, a common problem when remotely-sensed imagery is used. Despite these issues, planners rarely consider the effects of errors when choosing data for spatially explicit conservation prioritizations. Here we evaluate trade-offs between accuracy and resolution of hierarchical coral reef habitat data (geomorphology and benthic substrate) derived from remote sensing, in spatial planning for Kubulau District, Fiji. For both, we use accuracy information describing the probability that a mapped habitat classification is correct to design marine Reserve Networks that achieve habitat conservation targets, and demonstrate inadequacies of using habitat maps without accuracy data. We show that using more detailed habitat information ensures better representation of biogenic habitats (i.e. coral and seagrass), but leads to larger and more costly Reserves, because these data have more misclassification errors, and are also more expensive to obtain. Reduced impacts on fishers are possible using coarsely-classified data, which are also more cost-effective for planning Reserves if we account for data collection costs, but using these data may under-represent reef habitats that are important for fisheries and biodiversity, due to the maps low thematic resolution. Finally, we show that explicitly accounting for accuracy information in decisions maximizes the chance of successful conservation outcomes by reducing the risk of missing conservation representation targets, particularly when using finely classified data.
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using multivariate statistics to explore trade offs among spatial planning scenarios
2014Co-Authors: Linda R Harris, Hugh P. Possingham, Matthew E Watts, Ronel Nel, David S SchoemanAbstract:Scenario planning can be useful to guide decision-making under uncertainty. While systematic conservation planning can create protected-area Networks for multiple and complex Reserve-design scenarios, planners rarely compare different Reserve Networks explicitly, or quantify trade-offs among scenarios. We demonstrate the use of multivariate statistics traditionally applied in community ecology to compare Reserves designed under different scenarios, using conservation planning for beaches in South Africa as an example. Twelve Reserve-design scenarios were run in Marxan in a hierarchical experimental design with three levels: including/excluding the probability of site destruction; two different cost types; and three different configurations of existing terrestrial and marine Reserves. Multivariate statistics proved to be useful tools in the conservation planning context. In our case study, they showed that the trade-off associated with including the probability of site destruction during coastal Reserve design depended on the cost type: if the cost is related to the site-destruction probability then Reserves are significantly larger; if not, then Reserves are significantly more costly. In both cases, the configuration of existing Reserves locked a priori into the solutions was more important and resulted in significantly larger and more costly Reserves.Synthesis and applications. This study demonstrates a novel application of multivariate statistical tools to robustly quantify potential trade-offs among diverse sets of Reserve-design scenarios. These statistics can be applied: to support negotiations with stakeholders and decision-makers regarding Reserve configurations in the face of uncertainty; in Reserve-design sensitivity analyses; and in priority setting for future research and data collection to improve conservation plans.
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incorporating uncertainty associated with habitat data in marine Reserve design
2013Co-Authors: Vivitskaia J D Tulloch, Ayesha I T Tulloch, Chris Roelfsema, Hugh P. Possingham, Stacy D Jupiter, Carissa J KleinAbstract:Abstract One of the most pervasive forms of uncertainty in data used to make conservation decisions is error associated with mapping of conservation features. Whilst conservation planners should consider uncertainty associated with ecological data to make informed decisions, mapping error is rarely, if ever, accommodated in the planning process. Here, we develop a spatial conservation prioritization approach that accounts for the uncertainty inherent in coral reef habitat maps and apply it in the Kubulau District fisheries management area, Fiji. We use accuracy information describing the probability of occurrence of each habitat type, derived from remote sensing data validated by field surveys, to design a marine Reserve network that has a high probability of protecting a fixed percentage (10–90%) of every habitat type. We compare the outcomes of our approach to those of standard Reserve design approaches, where habitat-mapping errors are not known or ignored. We show that the locations of priority areas change between the standard and probabilistic approaches, with errors of omission and commission likely to occur if Reserve design does not accommodate mapping accuracy. Although consideration of habitat mapping accuracy leads to bigger Reserve Networks, they are unlikely to miss habitat conservation targets. We explore the trade-off between conservation feature representation and Reserve network area, with smaller Reserve Networks possible if we give up on trying to meet targets for habitats mapped with a low accuracy. The approach can be used with any habitat type at any scale to inform more robust and defensible conservation decisions in marine or terrestrial environments.
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planning for Reserve adequacy in dynamic landscapes maximizing future representation of vegetation communities under flood disturbance in the pantanal wetland
2011Co-Authors: Reinaldo Lourival, Matthew E Watts, Martin Drechsler, Edward T Game, Hugh P. PossinghamAbstract:Aim Using a probabilistic modelling framework, we aimed to incorporate landscape spatiotemporal dynamics into Reserve design. We employed a spatially explicit stochastic model, which integrates both hydrological and biological processes, to simulate the wetland’s biological succession. Location Pantanal wetland (with 140,000 km2) between Brazil, Bolivia and Paraguay. Methods We used the Reserve design software Marxan to optimize the current and future representation (up to 50 years) of 20% of five plant communities with maximum reliability (i.e. smallest uncertainty). The Kappa statistic was used to compare selection frequencies of individual sites through a set of planning timeframes (5, 17, 25 and 50 years) and the likely pattern of biological succession over these periods. Results Solutions based on static vegetation distributions were significantly dissimilar from solutions based on the expected modelled changes resulting from the flood disturbance and succession dynamics. Increasing the required reliability of biodiversity outcomes resulted in more expensive Reserve solutions. We demonstrated the flexibility of probabilistic decision-making methods to illuminate the trade-offs between reliability and efficiency of site selection. Main conclusions Considering the importance of habitat heterogeneity to the principles and practice of systematic conservation planning, it is notable that landscape dynamics have not been a central theme in conservation planning. In the case of the Pantanal hydrosere, acknowledging and planning for temporal dynamics required an ability to model succession and define acceptable levels of outcome reliability, but ultimately improved the long-term Adequacy of resulting Reserve Networks.
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effectiveness of marine Reserve Networks in representing biodiversity and minimizing impact to fishermen a comparison of two approaches used in california
2008Co-Authors: Carissa J Klein, Charles Steinback, Astrid Scholz, Hugh P. PossinghamAbstract:We compared the effectiveness of marine Reserve Networks designed using a numerical optimization tool with Networks designed by stakeholders during the course of California's Marine Life Protection Act Initiative at representing biodiversity and minimizing estimated negative impacts to fishermen. We used the same spatial data representing biodiversity and recreational fishing effort that were used by the stakeholders to design marine Reserves. In addition, we used commercial fishing data not explicitly available to the stakeholders. Networks of marine Reserves designed with numerical optimization tools represented the same amount of each habitat, or more, and had less of an estimated impact on commercial and recreational fisheries than Networks designed by the stakeholders. The Networks designed by the stakeholders could have represented 2.0–9.5% more of each habitat with no additional impact on the fisheries. Of four different marine Reserve proposals considered in the initiative, the proposal designed by fishermen was more efficient than the proposals designed by other stakeholder groups at representing biodiversity and minimizing impact to the fishing industry. These results highlight the necessity of using comprehensive information on fishing effort to design a Reserve network that efficiently minimizes negative socioeconomic impacts. We recommend that numerical optimization tools support, not replace, the stakeholder-driven Reserve design process along California's northern and southern coasts to help accomplish two of the initiative's core objectives: (1) Protect representative and unique marine habitats, and (2) Minimize negative socioeconomic impacts. The involvement of stakeholders is necessary as additional factors important to Reserve design can not be considered using a numerical optimization tool.
Geoff Wescott - One of the best experts on this subject based on the ideXlab platform.
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the role of multi tenure Reserve Networks in improving Reserve design and connectivity
2008Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks aim to connect areas managed for biodiversity conservation across public and private land. This paper seeks to determine to what extent multi-tenure Reserve Networks improve the Reserve design and connectivity of the public protected area estate, using three Networks in southeastern Australia as case studies. Network configuration varied considerably and those Networks with generally larger parcels tended to be better connected. On average, public land components were larger than private land components in all Networks. Two Networks had 18 components physically adjoining other network components while another had only 6 components adjoining. Importantly for two of the Networks, the average distance between the nearest neighbouring component was significantly less than average distances between public protected areas in the subregion. Thus these multi-tenure Reserve Networks acted to enhance the existing public protected area estate by increasing the potential linkages in the landscape and therefore the viability of individual public protected areas.
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evolving governance arrangements in multi tenure Reserve Networks
2008Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks (MTRNs) aim to connect areas managed for biodiversity conservation across public and private land (for example biosphere Reserves (BRs) and conservation management Networks (CMNs)). A key function of MTRNs is facilitating communication, information exchange and management activities between land managers of differing tenures not usually in contact with each other; governance arrangements are therefore crucial. Australian MTRNs vary greatly in their goals and measures of success, criteria for entry, ecosystems targeted, geographic extent and financial arrangements. The successful operation of a MTRN is likely to be influenced by a manager's confidence in the governance model/coordination arrangements (Belcher & Wellman 1991). We analysed the organizational structure of three Australian MTRNs (Fig. 1) including the objectives and role of the coordinating body, entry requirements, goals and measures of success, restrictions placed on the geographic or ecological extent of the network and financial arrangements. We highlight how substantial changes in governance arrangements have occurred for two of three Networks studied, suggesting a fluid evolution of MTRN structures is likely.
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ecosystem conservation in multi tenure Reserve Networks the contribution of land outside of publicly protected areas
2008Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks have been developed as a mechanism to improve cross tenure management and protection of biodiversity, but also as a means of accounting for biodiversity assets managed for conservation outside of protected areas on public land. We evaluated the contribution of multi-tenure Reserve Networks to enhancing the comprehensiveness and representativeness of ecosystems in publicly protected areas, using three Australian case studies. All Networks contributed to enhancing comprehensiveness and representativeness, but this contribution varied between Networks and between components of those Networks. Significantly, components on private land and "other public land" in all three Networks greatly enhanced the protection of some ecosystems at a subregional scale. The Grassy Box Woodlands Conservation Management Network, in particular made a substantial contribution to conservation, with most components protecting remnants of an endangered and under-represented ecosystem. Multi-Reserve conservation Networks not only act to protect threatened and under-Reserved ecosystems, but they also provide a mechanism to account for this protection. Thus, multi-tenure Reserve Networks have the potential to provide increased knowledge and understanding to conservation planning decision making processes.
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perceptions and attitudes of land managers in multi tenure Reserve Networks and the implications for conservation
2007Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks aim to connect areas managed for biodiversity conservation across public and private land and address the impacts of fragmentation on both biotic and social systems. The operation and function of Australian multi-tenure Reserve Networks as perceived by their land managers was investigated. Overall, the conservation of natural assets was the most frequently reported primary reason for involvement in a network. The perceived aims of the respective Networks largely reflected the response identified for involvement and management. Over 88% of managers considered their involvement in multi-tenure Reserve Networks to be a positive or very positive experience. A lack of resources and time for management were considered major limitations of these Networks. The majority (80%) of private land managers within Networks were willing to be included in a national Reserve system of conservation lands. As the Australian National Reserve System currently incorporates mostly public land, these findings have important and potentially positive implications for a greater role for protected private land.
Atte Moilanen - One of the best experts on this subject based on the ideXlab platform.
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optimizing resiliency of Reserve Networks to climate change multispecies conservation planning in the pacific northwest usa
2010Co-Authors: Carlos Carroll, Jeffrey R Dunk, Atte MoilanenAbstract:The effectiveness of a system of Reserves may be compromised under climate change as species’ habitat shifts to nonReserved areas, a problem that may be compounded when well-studied vertebrate species are used as conservation umbrellas for other taxa. The Northwest Forest Plan was among the first efforts to integrate conservation of wideranging focal species and localized endemics into regional conservation planning. We evaluated how effectively the plan’s focal species, the Northern Spotted Owl, acts as an umbrella for localized species under current and projected future climates and how the regional system of Reserves can be made more resilient to climate change. We used the program MAXENT to develop distribution models integrating climate data with vegetation variables for the owl and 130 localized species. We used the program ZONATION to identify a system of areas that efficiently captures habitat for both the owl and localized species and prioritizes refugial areas of climatic and topographic heterogeneity where current and future habitat for dispersal-limited species is in proximity. We projected future species’ distributions based on an ensemble of contrasting climate models, and incorporating uncertainty between alternate climate projections into the prioritization process. Reserve solutions based on the owl overlap areas of high localized-species richness but poorly capture core areas of localized species’ distribution. Congruence between priority areas across taxa increases when refugial areas are prioritized. Although corearea selection strategies can potentially increase the conservation value and resilience of regional Reserve systems, they accentuate contrasts in priority areas between species and over time and should be combined with a broadened taxonomic scope and increased attention to potential effects of climate change. Our results suggest that systems of fixed Reserves designed for resilience can increase the likelihood of retaining the biological diversity of forest ecosystems under climate change.
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the boundary quality penalty a quantitative method for approximating species responses to fragmentation in Reserve selection
2007Co-Authors: Atte Moilanen, Brendan A WintleAbstract:Aggregation of Reserve Networks is generally considered desirable for biological and economic reasons: aggregation reduces negative edge effects and facilitates metapopulation dynamics, which plausibly leads to improved persistence of species. Economically, aggregated Networks are less expensive to manage than fragmented ones. Therefore, many Reserve-design methods use qualitative heuristics, such as distance-based criteria or boundary-length penalties to induce Reserve aggregation. We devised a quantitative method that introduces aggregation into Reserve Networks. We call the method the boundary-quality penalty (BQP) because the biological value of a land unit (grid cell) is penalized when the unit occurs close enough to the edge of a Reserve such that a fragmentation or edge effect would reduce population densities in the Reserved cell. The BQP can be estimated for any habitat model that includes neighborhood (connectivity) effects, and it can be introduced into Reserve selection software in a standardized manner. We used the BQP in a Reserve-design case study of the Hunter Valley of southeastern Australia. The BQP resulted in a more highly aggregated Reserve network structure. The degree of aggregation required was specified by observed (albeit modeled) biological responses to fragmentation. Estimating the effects of fragmentation on individual species and incorporating estimated effects in the objective function of Reserve-selection algorithms is a coherent and defensible way to select aggregated Reserves. We implemented the BQP in the context of the Zonation method, but it could as well be implemented into any other spatially explicit Reserve-planning framework.
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planning for robust Reserve Networks using uncertainty analysis
2006Co-Authors: Atte Moilanen, Jane Elith, Mark A. Burgman, Brendan A Wintle, Michael C Runge, Andrew J Tyre, Yohay Carmel, Eric Fegraus, Yakov BenhaimAbstract:Abstract Planning land-use for biodiversity conservation frequently involves computer-assisted Reserve selection algorithms. Typically such algorithms operate on matrices of species presence–absence in sites, or on species-specific distributions of model predicted probabilities of occurrence in grid cells. There are practically always errors in input data—erroneous species presence–absence data, structural and parametric uncertainty in predictive habitat models, and lack of correspondence between temporal presence and long-run persistence. Despite these uncertainties, typical Reserve selection methods proceed as if there is no uncertainty in the data or models. Having two conservation options of apparently equal biological value, one would prefer the option whose value is relatively insensitive to errors in planning inputs. In this work we show how uncertainty analysis for Reserve planning can be implemented within a framework of information-gap decision theory, generating Reserve designs that are robust to uncertainty. Consideration of uncertainty involves modifications to the typical objective functions used in Reserve selection. Search for robust-optimal Reserve structures can still be implemented via typical Reserve selection optimization techniques, including stepwise heuristics, integer-programming and stochastic global search.
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uncertainty analysis favours selection of spatially aggregated Reserve Networks
2006Co-Authors: Atte Moilanen, Brendan A WintleAbstract:It has been widely argued that habitat fragmentation is bad for (meta)population persistence and that a high level of fragmentation is a similarly undesirable characteristic for a Reserve network. However, modelling the effects of fragmentation for many species is very difficult due to high data demands and uncertainty concerning its effect on particular species. Hence, several Reserve selection methods employ qualitative heuristics such as boundary length penalties that aggregate Reserve network structures. This aggregation usually comes at a cost because low quality habitats will be included for the sake of increased connectivity. Here a biologically justified method for designing aggregated Reserve Networks based on a technique called distribution smoothing is investigated. As with the boundary length penalty, its use incurs an apparent biological cost. However, taking a step further, potential negative effects of fragmentation on individual species are evaluated using a decision-theoretic uncertainty analysis approach. This analysis shows that the aggregated Reserve network (based on smoothed distributions) is likely to be biologically more valuable than a more fragmented one (based on habitat model predictions). The method is illustrated with a Reserve design case study in the Hunter Valley of south-eastern Australia. The uncertainty analysis method, based on information-gap decision theory, provides a systematic framework for making robust decisions under severe uncertainty, making it particularly well adapted to Reserve design problems.
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metapopulation dynamics and Reserve network design
2004Co-Authors: Mar Cabeza, Atte Moilanen, Hugh P. PossinghamAbstract:The ecological theories of island biogeography and metapopulation dynamics provide some guidance for the selection of Reserves. While some general concepts provide broad guidance, they are not useful in helping one choose between different sites and they are not universally true. Since the early 1980s, there has been much attention on developing systematic quantitative methods that use empirical biodiversity data and economic considerations to select a set of sites for biodiversity conservation. This chapter reviews quantitative methods for Reserve selection and then concentrates on new ideas that incorporate concepts from spatial ecology, particularly, metapopulation biology and landscape ecology. It compares a range of methods that consider spatiotemporal dynamics in different ways, and shows that the persistence of species in Reserve Networks is enhanced when spatial considerations are taken into account in Reserve network design. The chapter ends with a discussion on the problems of dynamic Reserve selection in an uncertain world where one needs to deal with dynamic populations and a dynamic landscape.
James A Fitzsimons - One of the best experts on this subject based on the ideXlab platform.
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the role of multi tenure Reserve Networks in improving Reserve design and connectivity
2008Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks aim to connect areas managed for biodiversity conservation across public and private land. This paper seeks to determine to what extent multi-tenure Reserve Networks improve the Reserve design and connectivity of the public protected area estate, using three Networks in southeastern Australia as case studies. Network configuration varied considerably and those Networks with generally larger parcels tended to be better connected. On average, public land components were larger than private land components in all Networks. Two Networks had 18 components physically adjoining other network components while another had only 6 components adjoining. Importantly for two of the Networks, the average distance between the nearest neighbouring component was significantly less than average distances between public protected areas in the subregion. Thus these multi-tenure Reserve Networks acted to enhance the existing public protected area estate by increasing the potential linkages in the landscape and therefore the viability of individual public protected areas.
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evolving governance arrangements in multi tenure Reserve Networks
2008Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks (MTRNs) aim to connect areas managed for biodiversity conservation across public and private land (for example biosphere Reserves (BRs) and conservation management Networks (CMNs)). A key function of MTRNs is facilitating communication, information exchange and management activities between land managers of differing tenures not usually in contact with each other; governance arrangements are therefore crucial. Australian MTRNs vary greatly in their goals and measures of success, criteria for entry, ecosystems targeted, geographic extent and financial arrangements. The successful operation of a MTRN is likely to be influenced by a manager's confidence in the governance model/coordination arrangements (Belcher & Wellman 1991). We analysed the organizational structure of three Australian MTRNs (Fig. 1) including the objectives and role of the coordinating body, entry requirements, goals and measures of success, restrictions placed on the geographic or ecological extent of the network and financial arrangements. We highlight how substantial changes in governance arrangements have occurred for two of three Networks studied, suggesting a fluid evolution of MTRN structures is likely.
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ecosystem conservation in multi tenure Reserve Networks the contribution of land outside of publicly protected areas
2008Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks have been developed as a mechanism to improve cross tenure management and protection of biodiversity, but also as a means of accounting for biodiversity assets managed for conservation outside of protected areas on public land. We evaluated the contribution of multi-tenure Reserve Networks to enhancing the comprehensiveness and representativeness of ecosystems in publicly protected areas, using three Australian case studies. All Networks contributed to enhancing comprehensiveness and representativeness, but this contribution varied between Networks and between components of those Networks. Significantly, components on private land and "other public land" in all three Networks greatly enhanced the protection of some ecosystems at a subregional scale. The Grassy Box Woodlands Conservation Management Network, in particular made a substantial contribution to conservation, with most components protecting remnants of an endangered and under-represented ecosystem. Multi-Reserve conservation Networks not only act to protect threatened and under-Reserved ecosystems, but they also provide a mechanism to account for this protection. Thus, multi-tenure Reserve Networks have the potential to provide increased knowledge and understanding to conservation planning decision making processes.
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perceptions and attitudes of land managers in multi tenure Reserve Networks and the implications for conservation
2007Co-Authors: James A Fitzsimons, Geoff WescottAbstract:Multi-tenure Reserve Networks aim to connect areas managed for biodiversity conservation across public and private land and address the impacts of fragmentation on both biotic and social systems. The operation and function of Australian multi-tenure Reserve Networks as perceived by their land managers was investigated. Overall, the conservation of natural assets was the most frequently reported primary reason for involvement in a network. The perceived aims of the respective Networks largely reflected the response identified for involvement and management. Over 88% of managers considered their involvement in multi-tenure Reserve Networks to be a positive or very positive experience. A lack of resources and time for management were considered major limitations of these Networks. The majority (80%) of private land managers within Networks were willing to be included in a national Reserve system of conservation lands. As the Australian National Reserve System currently incorporates mostly public land, these findings have important and potentially positive implications for a greater role for protected private land.
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history and attributes of selected australian multi tenure Reserve Networks
2005Co-Authors: James A Fitzsimons, Geoffrey WescottAbstract:The need for conservation planning across the landscape, regardless of tenure, is widely recognised. In Australia, attempts to coordinate the management of conservation lands are characterised by models such as Biosphere Reserves and Conservation Management Networks. This paper outlines the history behind the formation and development of three Networks in Australia—the Bookmark Biosphere Reserve, the Gippsland Plains Conservation Management Network, and the Grassy Box Woodlands Conservation Management Network—with particular emphasis on the tenure and protection attributes of the various components within these Networks. Despite having a similar number of components, the total area represented in the Networks varied markedly. There were few similarities in the proportion of components of various tenures and protection mechanisms among Networks. Composition of Networks is likely to be strongly influenced by both historical factors (degree of subdivision, land ownership and remaining vegetation) and contemporary factors (aims of the network and willingness of landowners to participate). Continued research into both the evolution and the physical and social dynamics of multi-tenure Reserve Networks enables a better understanding of their operation, and will ultimately assist in improved conservation planning across the landscape.
Glenn R. Almany - One of the best experts on this subject based on the ideXlab platform.
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planning marine Reserve Networks for both feature representation and demographic persistence using connectivity patterns
2016Co-Authors: Michael Bode, David H Williamson, Hugo B Harrison, Jess K Hopf, Rebecca Weeks, Glenn R. Almany, Geoff Jones, Robert L PresseyAbstract:Marine Reserve Networks must ensure the representation of important conservation features, and also guarantee the persistence of key populations. For many species, designing Reserve Networks is complicated by the absence or limited availability of spatial and life-history data. This is particularly true for data on larval dispersal, which has only recently become available. However, systematic conservation planning methods currently incorporate demographic processes through unsatisfactory surrogates. There are therefore two key challenges to designing marine Reserve Networks that achieve feature representation and demographic persistence constraints. First, constructing a method that efficiently incorporates persistence as well as complementary feature representation. Second, incorporating persistence using a mechanistic description of population viability, rather than a proxy such as size or distance. Here we construct a novel systematic conservation planning method that addresses both challenges, and parameterise it to design a hypothetical marine Reserve network for fringing coral reefs in the Keppel Islands, Great Barrier Reef, Australia. For this application, we describe how demographic persistence goals can be constructed for an important reef fish species in the region, the bar-cheeked trout (Plectropomus maculatus). We compare Reserve Networks that are optimally designed for either feature representation or demographic persistence, with a Reserve network that achieves both goals simultaneously. As well as being practically applicable, our analyses also provide general insights into marine Reserve planning for both representation and demographic persistence. First, persistence constraints for dispersive organisms are likely to be much harder to achieve than representation targets, due to their greater complexity. Second, persistence and representation constraints pull the Reserve network design process in divergent directions, making it difficult to efficiently achieve both constraints. Although our method can be readily applied to the data-rich Keppel Islands case study, we finally consider the factors that limit the method's utility in information-poor contexts common in marine conservation.
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marine ecology Reserve Networks are necessary but not sufficient
2015Co-Authors: Glenn R. AlmanyAbstract:New work reveals that the large network of no-take marine Reserves on the Great Barrier Reef is working splendidly. However, bold, global action is needed to eliminate threats that Reserves cannot guard against.
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designing marine Reserves for fisheries management biodiversity conservation and climate change adaptation
2014Co-Authors: Alison Green, Glenn R. Almany, Leanne Fernandes, Rene Abesamis, Elizabeth Mcleod, Porfirio M Alino, Alan T White, Rod Salm, John Tanzer, Robert L PresseyAbstract:Overfishing and habitat destruction due to local and global threats are undermining fisheries, biodiversity, and the long-term sustainability of tropical marine ecosystems worldwide, including in the Coral Triangle. Well-designed and effectively managed marine Reserve Networks can reduce local threats, and contribute to achieving multiple objectives regarding fisheries management, biodiversity conservation and adaptation to changes in climate and ocean chemistry. Previous studies provided advice regarding ecological guidelines for designing marine Reserves to achieve one or two of these objectives. While there are many similarities in these guidelines, there are key differences that provide conflicting advice. Thus, there is a need to provide integrated guidelines for practitioners who wish to design marine Reserves to achieve all three objectives simultaneously. Scientific advances regarding fish connectivity and recovery rates, and climate and ocean change vulnerability, also necessitate refining advice...
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larval export from marine Reserves and the recruitment benefit for fish and fisheries
2012Co-Authors: David H Williamson, Hugo B Harrison, Glenn R. Almany, Garry R Russ, Richard D Evans, Simon R Thorrold, Kevin A Feldheim, Lynne Van Herwerden, Serge PlanesAbstract:Marine Reserves, areas closed to all forms of fishing, continue to be advocated and implemented to supplement fisheries and conserve populations [ [1], [2], [3] and [4]]. However, although the reproductive potential of important fishery species can dramatically increase inside Reserves [ [5], [6], [7] and [8]], the extent to which larval offspring are exported and the relative contribution of Reserves to recruitment in fished and protected populations are unknown [ [4], [9], [10] and [11]]. Using genetic parentage analyses, we resolve patterns of larval dispersal for two species of exploited coral reef fish within a network of marine Reserves on the Great Barrier Reef. In a 1,000 km2 study area, populations resident in three Reserves exported 83% (coral trout, Plectropomus maculatus) and 55% (stripey snapper, Lutjanus carponotatus) of assigned offspring to fished reefs, with the remainder having recruited to natal Reserves or other Reserves in the region. We estimate that Reserves, which account for just 28% of the local reef area, produced approximately half of all juvenile recruitment to both Reserve and fished reefs within 30 km. Our results provide compelling evidence that adequately protected Reserve Networks can make a significant contribution to the replenishment of populations on both Reserve and fished reefs at a scale that benefits local stakeholders.
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Connectivity, biodiversity conservation and the design of marine Reserve Networks for coral reefs
2009Co-Authors: Glenn R. Almany, S. R. Connolly, J. D. Hogan, Laurence J. Mccook, M. Mills, D D Heath, Robert L Pressey, G. P. Jones, D H WilliamsonAbstract:Networks of no-take Reserves are important for protecting coral reef biodiversity from climate change and other human impacts. Ensuring that Reserve populations are connected to each other and non-Reserve populations by larval dispersal allows for recovery from disturbance and is a key aspect of resilience. In general, connectivity between Reserves should increase as the distance between them decreases. However, enhancing connectivity may often tradeoff against a network’s ability to representatively sample the system’s natural variability. This “representation” objective is typically measured in terms of species richness or diversity of habitats, but has other important elements (e.g., minimizing the risk that multiple Reserves will be impacted by catastrophic events). Such representation objectives tend to be better achieved as Reserves become more widely spaced. Thus, optimizing the location, size and spacing of Reserves requires both an understanding of larval dispersal and explicit consideration of how well the network represents the broader system; indeed the lack of an integrated theory for optimizing tradeoffs between connectivity and representation objectives has inhibited the incorporation of connectivity into Reserve selection algorithms. This article addresses these issues by (1) updating general recommendations for the location, size and spacing of Reserves based on emerging data on larval dispersal in corals and reef fishes, and on considerations for maintaining genetic diversity; (2) using a spatial analysis of the Great Barrier Reef Marine Park to examine potential tradeoffs between connectivity and representation of biodiversity and (3) describing a framework for incorporating environmental fluctuations into the conceptualization of the tradeoff between connectivity and representation, and that expresses both in a common, demographically meaningful currency, thus making optimization possible.
