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Horswill C, Manica A, Daunt F, Newell M, Wanless S, Wood M, Matthiopoulos J. Improving assessments of data‐limited populations using life‐history theory. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.13863] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Cat Horswill
- Institute of Biodiversity Animal Health & Comparative Medicine University of Glasgow Glasgow UK
- Department of Zoology University of Cambridge Cambridge UK
- ZSL Institute of Zoology London UK
- Centre for Biodiversity and Environmental Research Department of Genetics, Evolution and Environment University College London London UK
| | - Andrea Manica
- Department of Zoology University of Cambridge Cambridge UK
| | | | - Mark Newell
- UK Centre for Ecology & Hydrology Penicuik UK
| | | | - Matthew Wood
- School of Natural and Social Sciences University of Gloucestershire Cheltenham UK
| | - Jason Matthiopoulos
- Institute of Biodiversity Animal Health & Comparative Medicine University of Glasgow Glasgow UK
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Congruent Genetic and Demographic Dispersal Rates in a Natural Metapopulation at Equilibrium. Genes (Basel) 2021; 12:genes12030362. [PMID: 33802587 PMCID: PMC7999359 DOI: 10.3390/genes12030362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 01/01/2023] Open
Abstract
Understanding the functioning of natural metapopulations at relevant spatial and temporal scales is necessary to accurately feed both theoretical eco-evolutionary models and conservation plans. One key metric to describe the dynamics of metapopulations is dispersal rate. It can be estimated with either direct field estimates of individual movements or with indirect molecular methods, but the two approaches do not necessarily match. We present a field study in a large natural metapopulation of the butterfly Boloria eunomia in Belgium surveyed over three generations using synchronized demographic and genetic datasets with the aim to characterize its genetic structure, its dispersal dynamics, and its demographic stability. By comparing the census and effective population sizes, and the estimates of dispersal rates, we found evidence of stability at several levels: constant inter-generational ranking of population sizes without drastic historical changes, stable genetic structure and geographically-influenced dispersal movements. Interestingly, contemporary dispersal estimates matched between direct field and indirect genetic assessments. We discuss the eco-evolutionary mechanisms that could explain the described stability of the metapopulation, and suggest that destabilizing agents like inter-generational fluctuations in population sizes could be controlled by a long adaptive history of the species to its dynamic local environment. We finally propose methodological avenues to further improve the match between demographic and genetic estimates of dispersal.
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Messerman AF, Semlitsch RD, Leal M. Estimating Survival for Elusive Juvenile Pond‐Breeding Salamanders. J Wildl Manage 2020. [DOI: 10.1002/jwmg.21815] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Manuel Leal
- University of Missouri 612 Hitt Street, 209 Tucker Hall Columbia MO 65211 USA
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Radchuk V, Kramer-Schadt S, Grimm V. Transferability of Mechanistic Ecological Models Is About Emergence. Trends Ecol Evol 2019; 34:487-488. [PMID: 30795841 DOI: 10.1016/j.tree.2019.01.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/18/2019] [Accepted: 01/23/2019] [Indexed: 11/25/2022]
Affiliation(s)
- Viktoriia Radchuk
- Department of Ecological Dynamics, Leibniz Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Straße 17, Berlin, Germany.
| | - Stephanie Kramer-Schadt
- Department of Ecological Dynamics, Leibniz Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Straße 17, Berlin, Germany; Department of Ecology, Technische Universität Berlin, Rothenburgstrasse 12, 12165 Berlin, Germany
| | - Volker Grimm
- Department of Ecological Modelling, Helmholtz Centre for Environmental Research - UFZ, Permoserstr. 15, Leipzig, Germany; Institute for Biochemistry and Biology, University of Potsdam, Maulbeerallee 2, Potsdam, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, Leipzig, Germany
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Che-Castaldo J, Che-Castaldo C, Neel MC. Predictability of demographic rates based on phylogeny and biological similarity. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2018; 32:1290-1300. [PMID: 29790214 DOI: 10.1111/cobi.13135] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 05/06/2018] [Indexed: 06/08/2023]
Abstract
Lack of demographic data for most of the world's threatened species is a widespread problem that precludes viability-based status assessments for species conservation. A commonly suggested solution is to use data from species that are closely related or biologically similar to the focal species. This approach assumes similar species and populations of the same species have similar demographic rates, an assumption that has yet to be thoroughly tested. We constructed a Bayesian hierarchical model with data on 425 plant species to predict demographic rates (intrinsic rate of population growth, recruit survival, juvenile survival, adult survival, and fecundity) based on biological traits and phylogenetic relatedness. Generally, we found small effects of species-level traits (except woody polycarpic species tended to have high adult survival rates that increased with plant height) and a weak phylogenetic signal for 4 of the 5 demographic parameters examined. Patterns were stronger in adult survival and fecundity than other demographic rates; however, the unexplained variances at both the species and population levels were high for all demographic rates. For species lacking demographic data, our model produced large, often inaccurate, prediction intervals that may not be useful in a management context. Our findings do not support the assumption that biologically similar or closely related species have similar demographic rates and provide further evidence that direct monitoring of focal species and populations is necessary for informing conservation status assessments.
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Affiliation(s)
- Judy Che-Castaldo
- Department of Conservation and Science, Lincoln Park Zoo, 2001 N. Clark St., Chicago, IL 60614, U.S.A
| | - Christian Che-Castaldo
- Department of Ecology and Evolution, Stony Brook University, 113 Life Sciences Building, Stony Brook, NY 11794, U.S.A
| | - Maile C Neel
- Department of Plant Science and Landscape Architecture and Department of Entomology, University of Maryland, 6117 Plant Sciences Building, College Park, MD 20742, U.S.A
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Simple or complex: Relative impact of data availability and model purpose on the choice of model types for population viability analyses. Ecol Modell 2016. [DOI: 10.1016/j.ecolmodel.2015.11.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Hernández-Camacho CJ, Bakker VJ, Aurioles-Gamboa D, Laake J, Gerber LR. The Use of Surrogate Data in Demographic Population Viability Analysis: A Case Study of California Sea Lions. PLoS One 2015; 10:e0139158. [PMID: 26413746 PMCID: PMC4587556 DOI: 10.1371/journal.pone.0139158] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 09/08/2015] [Indexed: 11/18/2022] Open
Abstract
Reliable data necessary to parameterize population models are seldom available for imperiled species. As an alternative, data from populations of the same species or from ecologically similar species have been used to construct models. In this study, we evaluated the use of demographic data collected at one California sea lion colony (Los Islotes) to predict the population dynamics of the same species from two other colonies (San Jorge and Granito) in the Gulf of California, Mexico, for which demographic data are lacking. To do so, we developed a stochastic demographic age-structured matrix model and conducted a population viability analysis for each colony. For the Los Islotes colony we used site-specific pup, juvenile, and adult survival probabilities, as well as birth rates for older females. For the other colonies, we used site-specific pup and juvenile survival probabilities, but used surrogate data from Los Islotes for adult survival probabilities and birth rates. We assessed these models by comparing simulated retrospective population trajectories to observed population trends based on count data. The projected population trajectories approximated the observed trends when surrogate data were used for one colony but failed to match for a second colony. Our results indicate that species-specific and even region-specific surrogate data may lead to erroneous conservation decisions. These results highlight the importance of using population-specific demographic data in assessing extinction risk. When vital rates are not available and immediate management actions must be taken, in particular for imperiled species, we recommend the use of surrogate data only when the populations appear to have similar population trends.
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Affiliation(s)
| | - Victoria. J. Bakker
- Department of Ecology, Montana State University, Bozeman, Montana, United States of America
| | - David Aurioles-Gamboa
- Laboratorio de Ecología de Pinnípedos ‘‘Burney J. Le Boeuf”, Centro Interdisciplinario de Ciencias Marinas, Instituto Politécnico Nacional, La Paz, Baja California Sur, México
| | - Jeff Laake
- National Marine Mammal Laboratory, Alaska Fisheries Science Center, National Oceanic and Atmospheric Administration, Seattle, Washington, United States of America
| | - Leah R. Gerber
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
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Hawkes LA, McGowan A, Broderick AC, Gore S, Wheatley D, White J, Witt MJ, Godley BJ. High rates of growth recorded for hawksbill sea turtles in Anegada, British Virgin Islands. Ecol Evol 2014; 4:1255-66. [PMID: 24834324 PMCID: PMC4020687 DOI: 10.1002/ece3.1018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 02/04/2014] [Accepted: 02/08/2014] [Indexed: 12/01/2022] Open
Abstract
Management of species of conservation concern requires knowledge of demographic parameters, such as rates of recruitment, survival, and growth. In the Caribbean, hawksbill turtles (Eretmochelys imbricata) have been historically exploited in huge numbers to satisfy trade in their shells and meat. In the present study, we estimated growth rate of juvenile hawksbill turtles around Anegada, British Virgin Islands, using capture–mark–recapture of 59 turtles over periods of up to 649 days. Turtles were recaptured up to six times, having moved up to 5.9 km from the release location. Across all sizes, turtles grew at an average rate of 9.3 cm year−1 (range 2.3–20.3 cm year−1), and gained mass at an average of 3.9 kg year−1 (range 850 g–16.1 kg year−1). Carapace length was a significant predictor of growth rate and mass gain, but there was no relationship between either variable and sea surface temperature. These are among the fastest rates of growth reported for this species, with seven turtles growing at a rate that would increase their body size by more than half per year (51–69% increase in body length). This study also demonstrates the importance of shallow water reef systems for the developmental habitat for juvenile hawksbill turtles. Although growth rates for posthatching turtles in the pelagic, and turtles larger than 61 cm, are not known for this population, the implications of this study are that Caribbean hawksbill turtles in some areas may reach body sizes suggesting sexual maturity in less time than previously considered.
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Affiliation(s)
- Lucy A Hawkes
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus Penryn, TR10 9EZ, U.K
| | - Andrew McGowan
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus Penryn, TR10 9EZ, U.K
| | - Annette C Broderick
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus Penryn, TR10 9EZ, U.K
| | - Shannon Gore
- Conservation and Fisheries Department, Ministry of Natural Resources and Labour PO Box 3323, Road Town, Tortola, British Virgin Islands
| | | | - Jim White
- The Settlement Anegada, British Virgin Islands
| | - Matthew J Witt
- Environment and Sustainability Institute, University of Exeter, Penryn Campus Penryn, Cornwall, TR10 9EZ, U.K
| | - Brendan J Godley
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus Penryn, TR10 9EZ, U.K
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Moir ML, Hughes L, Vesk PA, Leng MC. Which host-dependent insects are most prone to coextinction under changed climates? Ecol Evol 2014; 4:1295-312. [PMID: 24834327 PMCID: PMC4020690 DOI: 10.1002/ece3.1021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 02/13/2014] [Accepted: 02/13/2014] [Indexed: 11/09/2022] Open
Abstract
Coextinction (loss of dependent species with their host or partner species) presents a threat to untold numbers of organisms. Climate change may act synergistically to accelerate rates of coextinction. In this review, we present the first synthesis of the available literature and propose a novel schematic diagram that can be used when assessing the potential risk climate change represents for dependent species. We highlight traits that may increase the susceptibility of insect species to coextinction induced by climate change, suggest the most influential host characteristics, and identify regions where climate change may have the greatest impact on dependent species. The aim of this review was to provide a platform for future research, directing efforts toward taxa and habitats at greatest risk of species loss through coextinction accelerated by climate change.
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Affiliation(s)
- Melinda L Moir
- School of Plant Biology, University of Western Australia Crawley, Western Australia, 6009, Australia ; School of Botany, University of Melbourne Parkville, Victoria, 3010, Australia
| | - Lesley Hughes
- Department of Biological Sciences, Macquarie University North Ryde, New South Wales, 2109, Australia
| | - Peter A Vesk
- School of Botany, University of Melbourne Parkville, Victoria, 3010, Australia
| | - Mei Chen Leng
- School of Plant Biology, University of Western Australia Crawley, Western Australia, 6009, Australia
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Turlure C, Radchuk V, Baguette M, Meijrink M, den Burg A, Vries MW, Duinen GJ. Plant quality and local adaptation undermine relocation in a bog specialist butterfly. Ecol Evol 2012; 3:244-54. [PMID: 23467336 PMCID: PMC3586634 DOI: 10.1002/ece3.427] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 10/16/2012] [Accepted: 10/16/2012] [Indexed: 11/25/2022] Open
Abstract
The butterfly Boloria aquilonaris is a specialist of oligotrophic ecosystems. Population viability analysis predicted the species to be stable in Belgium and to collapse in the Netherlands with reduced host plant quality expected to drive species decline in the latter. We tested this hypothesis by rearing B. aquilonaris caterpillars from Belgian and Dutch sites on host plants (the cranberry, Vaccinium oxycoccos). Dutch plant quality was lower than Belgian one conferring lower caterpillar growth rate and survival. Reintroduction and/or supplementation may be necessary to ensure the viability of the species in the Netherlands, but some traits may have been selected solely in Dutch caterpillars to cope with gradual changes in host plant quality. To test this hypothesis, the performance of Belgian and Dutch caterpillars fed with plants from both countries were compared. Dutch caterpillars performed well on both plant qualities, whereas Belgian caterpillars could not switch to lower quality plants. This can be considered as an environmentally induced plastic response of caterpillars and/or a local adaptation to plant quality, which precludes the use of Belgian individuals as a unique solution for strengthening Dutch populations. More generally, these results stress that the relevance of local adaptation in selecting source populations for relocation may be as important as restoring habitat quality.
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Affiliation(s)
- Camille Turlure
- Earth and Life Institute, Universite catholique de Louvain - Biodiversity Research Centre Place Croix du Sud, 4, 1348, Louvain-la-Neuve, Belgium ; Muséum National d'Histoire Naturelle (MNHN) - Ecologie et Gestion de la Biodiversité, Avenue du Petit Château 1, 91800 Brunoy France
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Devenish-Nelson ES, Harris S, Soulsbury CD, Richards SA, Stephens PA. Demography of a carnivore, the red fox, Vulpes vulpes: what have we learnt from 70 years of published studies? OIKOS 2012. [DOI: 10.1111/j.1600-0706.2012.20706.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Radchuk V, Turlure C, Schtickzelle N. Each life stage matters: the importance of assessing the response to climate change over the complete life cycle in butterflies. J Anim Ecol 2012; 82:275-85. [PMID: 22924795 DOI: 10.1111/j.1365-2656.2012.02029.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 07/14/2012] [Indexed: 11/27/2022]
Abstract
As ectothermic organisms, butterflies have widely been used as models to explore the predicted impacts of climate change. However, most studies explore only one life stage; to our best knowledge, none have integrated the impact of temperature on the vital rates of all life stages for a species of conservation concern. Besides, most population viability analysis models for butterflies are based on yearly population growth rate, precluding the implementation and assessment of important climate change scenarios, where climate change occurs mainly, or differently, during some seasons. Here, we used a combination of laboratory and field experiments to quantify the impact of temperature on all life stages of a vulnerable glacial relict butterfly. Next, we integrated these impacts into an overall population response using a deterministic periodic matrix model and explored the impact of several climate change scenarios. Temperature positively affected egg, pre-diapause larva and pupal survival, and the number of eggs laid by a female; only the survival of overwintering larva was negatively affected by an increase in temperature. Despite the positive impact of warming on many life stages, population viability was reduced under all scenarios, with predictions of much shorter times to extinction than under the baseline (current temperature situation) scenario. Indeed, model predictions were the most sensitive to changes in survival of overwintering larva, the only stage negatively affected by warming. A proper consideration of every stage of the life cycle is important when designing conservation guidelines in the light of climate change. This is in line with the resource-based habitat view, which explicitly refers to the habitat as a collection of resources needed for all life stages of the species. We, therefore, encourage adopting a resource-based habitat view for population viability analysis and development of conservation guidelines for butterflies, and more generally, other organisms. Life stages that are cryptic or difficult to study should not be forsaken as they may be key determinants in the overall response to climate change, as we found with overwintering Boloria eunomia larvae.
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Affiliation(s)
- Viktoriia Radchuk
- Biodiversity Research Centre, Earth & Life Institute, Université catholique de Louvain, Place Croix du Sud, 4, L7.07.04, 1348, Louvain-la-Neuve, Belgium.
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Radchuk V, Wallisdevries MF, Schtickzelle N. Spatially and financially explicit population viability analysis of Maculinea alcon in The Netherlands. PLoS One 2012; 7:e38684. [PMID: 22719922 PMCID: PMC3375285 DOI: 10.1371/journal.pone.0038684] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 05/09/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The conservation of species structured in metapopulations involves an important dilemma of resource allocation: should investments be directed at restoring/enlarging habitat patches or increasing connectivity. This is still an open question for Maculinea species despite they are among the best studied and emblematic butterfly species, because none of the population dynamics models developed so far included dispersal. METHODOLOGY/PRINCIPAL FINDINGS We developed the first spatially and financially explicit Population Viability Analysis model for Maculinea alcon, using field data from The Netherlands. Implemented using the RAMAS/GIS platform, the model incorporated both local (contest density dependence, environmental and demographic stochasticities), and regional population dynamics (dispersal rates between habitat patches). We selected four habitat patch networks, contrasting in several basic features (number of habitat patches, their quality, connectivity, and occupancy rate) to test how these features are affecting the ability to enhance population viability of four basic management options, designed to incur the same costs: habitat enlargement, habitat quality improvement, creation of new stepping stone habitat patches, and reintroduction of captive-reared butterflies. The PVA model was validated by the close match between its predictions and independent field observations on the patch occupancy pattern. The four patch networks differed in their sensitivity to model parameters, as well as in the ranking of management options. Overall, the best cost-effective option was enlargement of existing habitat patches, followed by either habitat quality improvement or creation of stepping stones depending on the network features. Reintroduction was predicted to generally be inefficient, except in one specific patch network. CONCLUSIONS/SIGNIFICANCE Our results underline the importance of spatial and regional aspects (dispersal and connectivity) in determining the impact of conservation actions, even for a species previously considered as sedentary. They also illustrate that failure to account for the cost of management scenarios can lead to very different conclusions.
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Affiliation(s)
- Viktoriia Radchuk
- Biodiversity Research Centre, Earth & Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium.
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Stevens VM, Trochet A, Van Dyck H, Clobert J, Baguette M. How is dispersal integrated in life histories: a quantitative analysis using butterflies. Ecol Lett 2011; 15:74-86. [DOI: 10.1111/j.1461-0248.2011.01709.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Fric Z, Hula V, Klimova M, Zimmermann K, Konvicka M. Dispersal of four fritillary butterflies within identical landscape. Ecol Res 2010. [DOI: 10.1007/s11284-009-0684-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Wenger SJ. Use of surrogates to predict the stressor response of imperiled species. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2008; 22:1564-1571. [PMID: 18680507 DOI: 10.1111/j.1523-1739.2008.01013.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Rare or narrowly distributed species may be threatened by stressors to which they have never been exposed or for which data are very limited. In such cases the species response cannot be predicted on the basis of directly measured data, but may be inferred from the response of one or more appropriate surrogate species. Here, I propose a practical way to use the stressor response of one or more surrogate species to develop a working hypothesis or model of the stressor response of the target species. The process has 4 steps: (1) identify one or more candidate surrogate species, (2) model the relationship between the stressor and the response variable of interest for the surrogate species, (3) adapt the stressor-response relationship from the surrogate species to a model for the target species, possibly using Bayesian methods, and (4) incorporate additional data as they become available and adjust the response model of the target species appropriately. I applied the approach to an endangered fish species, the amber darter (Percina antesella), which is potentially threatened by urbanization. I used a Bayesian approach to combine data from a surrogate species (the bronze darter[Percina palmaris]) with available data for the amber darter to produce a model of expected amber darter response. Although this approach requires difficult decisions on the part of the manager, especially in the selection of surrogate species, its value lies in the fact that all assumptions are clearly stated in the form of hypotheses, which may be scrutinized and tested. It therefore provides a rational basis for instituting management policy even in the face of considerable uncertainty.
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Affiliation(s)
- Seth J Wenger
- University of Georgia River Basin Center, 110 Riverbend Road, Athens, GA 30602-1510, USA
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Baguette M, Schtickzelle N. Negative relationship between dispersal distance and demography in butterfly metapopulations. Ecology 2006; 87:648-54. [PMID: 16602294 DOI: 10.1890/04-1631] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Little is known about the connection between demography and dispersal in metapopulations. The meta-analysis of the population time series of five butterfly species indicated that (meta)population dynamics are driven by density-dependent factors. Inter-specific comparison reveals a significant inverse relationship between population growth rate and the magnitude of dispersal distance. As the range of dispersal distances is constrained by the patch system, dispersing individuals moving too far away would (probably) get lost. This generates selective pressures on individuals with a high dispersal propensity, but favors individuals investing more in reproduction and results in a higher (meta)population growth rate. From a conservation perspective, individuals from (meta)populations and species sacrificing dispersal for the sake of reproductive performances are most vulnerable because of their higher sensitivity to stochastic events: the temporal variation of growth rate was much higher in the two metapopulations where dispersal was limited.
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Affiliation(s)
- Michel Baguette
- Biodiversity Research Centre, University of Louvain (UCL), Unité d'Ecologie et de Biogéographie, Croix du Sud 4, Louvain-la-Neuve, B-1348 Belgium.
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