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Balseiro A, Herrero-García G, García Marín JF, Balsera R, Monasterio JM, Cubero D, de Pedro G, Oleaga Á, García-Rodríguez A, Espinoza I, Rabanal B, Aduriz G, Tuñón J, Gortázar C, Royo LJ. New threats in the recovery of large carnivores inhabiting human-modified landscapes: the case of the Cantabrian brown bear (Ursus arctos). Vet Res 2024; 55:24. [PMID: 38395920 PMCID: PMC10893660 DOI: 10.1186/s13567-024-01279-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 02/02/2024] [Indexed: 02/25/2024] Open
Abstract
Understanding mortality causes is important for the conservation of endangered species, especially in small and isolated populations inhabiting anthropized landscapes where both natural and human-caused mortality may hinder the conservation of these species. We investigated the mortality causes of 53 free-ranging brown bears (Ursus arctos) found dead between 1998 and 2023 in the Cantabrian Mountains (northwestern Spain), a highly human-modified region where bears are currently recovering after being critically threatened in the last century. We detected natural traumatic injuries in 52.63% and infectious diseases in 39.47% of the 38 bears for which the mortality causes were registered, with 21.05% of these cases presenting signs of both infectious diseases and traumas. More specifically, almost 30% of the bears died during or after intraspecific fights, including sexually selected infanticide (10.53%). In addition, primary infectious diseases such as infectious canine hepatitis, distemper, clostridiosis and colibacillosis caused the death of 15.79% of the bears. The number of direct human-caused deaths (i.e., shooting, poisoning, snare) decreased over the study period. This study also reveals three new mortality causes triggered by pathogens, two of which-Clostridium novyi and verotoxigenic Escherichia coli-not previously described in ursids, and the other one, canine distemper virus, never reported in brown bears as cause of death. New management strategies for the conservation of Cantabrian bears, which are urgently needed due to the rapid expansion of the population, should consider the mortality causes described in this study and must promote further research to elucidate how the high prevalence of infectious diseases may threaten the current recovery of the population.
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Affiliation(s)
- Ana Balseiro
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, 24071, León, Spain.
| | - Gloria Herrero-García
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, 24071, León, Spain
| | | | - Ramón Balsera
- Dirección General de Medio Natural y Planificación Rural del Principado de Asturias, 33007, Oviedo, Asturias, Spain
| | - Juana María Monasterio
- Dirección General de Medio Natural y Planificación Rural del Principado de Asturias, 33007, Oviedo, Asturias, Spain
| | - David Cubero
- Dirección General de Patrimonio Natural y Política Forestal de La Junta de Castilla y León, 47014, Valladolid, Castilla y León, Spain
| | - Gabriel de Pedro
- Dirección General de Patrimonio Natural y Política Forestal de La Junta de Castilla y León, 47014, Valladolid, Castilla y León, Spain
| | - Álvaro Oleaga
- Sociedad de Servicios del Principado de Asturias S.A. (SERPA), La Laboral, 33203, Gijón, Spain
| | - Alberto García-Rodríguez
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, 24071, León, Spain
| | - Israel Espinoza
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, 24071, León, Spain
| | - Benjamín Rabanal
- Laboratorio de Técnicas Instrumentales, Facultad de Veterinaria, Universidad de León, 24071, León, Spain
| | - Gorka Aduriz
- Departamento de Sanidad Animal, NEIKER-Instituto Vasco de Investigación y Desarrollo Agrario, 48160, Derio (Bizkaia), Spain
| | - José Tuñón
- Fundación Oso de Asturias, 33114, Proaza, Asturias, Spain
| | | | - Luis José Royo
- Departamento de Biología Funcional, Genética, Universidad de Oviedo, 33006, Oviedo, Spain
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2
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Díaz‐Fernández M, Naves J, Revilla E. Conservation implications of range dynamics in endangered populations: An example with brown bears. CONSERVATION SCIENCE AND PRACTICE 2023. [DOI: 10.1111/csp2.12894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- Manuel Díaz‐Fernández
- Department of Conservation Biology Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (EBD‐CSIC) Américo Vespucio, 26 Seville Spain
| | - Javier Naves
- Department of Conservation Biology Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (EBD‐CSIC) Américo Vespucio, 26 Seville Spain
| | - Eloy Revilla
- Department of Conservation Biology Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (EBD‐CSIC) Américo Vespucio, 26 Seville Spain
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3
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Zarzo‐Arias A, Penteriani V, Gábor L, Šímová P, Grattarola F, Moudrý V. Importance of data selection and filtering in species distribution models: A case study on the Cantabrian brown bear. Ecosphere 2022. [DOI: 10.1002/ecs2.4284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Alejandra Zarzo‐Arias
- Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (MNCN‐CSIC) Madrid Spain
- Universidad de Oviedo Oviedo Spain
- Department of Spatial Sciences, Faculty of Environmental Sciences Czech University of Life Sciences Prague Prague Czech Republic
| | - Vincenzo Penteriani
- Department of Evolutionary Ecology Museo Nacional de Ciencias Naturales (MNCN‐CSIC) Madrid Spain
- Biodiversity Research Institute (IMIB, CSIC‐UO‐PA) Mieres Spain
| | - Lukáš Gábor
- Department of Spatial Sciences, Faculty of Environmental Sciences Czech University of Life Sciences Prague Prague Czech Republic
- Department of Ecology and Evolutionary Biology Yale University New Haven Connecticut USA
- Center for Biodiversity and Global Change Yale University New Haven Connecticut USA
| | - Petra Šímová
- Department of Spatial Sciences, Faculty of Environmental Sciences Czech University of Life Sciences Prague Prague Czech Republic
| | - Florencia Grattarola
- Department of Spatial Sciences, Faculty of Environmental Sciences Czech University of Life Sciences Prague Prague Czech Republic
| | - Vítězslav Moudrý
- Department of Spatial Sciences, Faculty of Environmental Sciences Czech University of Life Sciences Prague Prague Czech Republic
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González‐Bernardo E, Delgado MDM, Matos DGG, Zarzo‐Arias A, Morales‐González A, Ruiz‐Villar H, Skuban M, Maiorano L, Ciucci P, Balbontín J, Penteriani V. The influence of road networks on brown bear spatial distribution and habitat suitability in a human‐modified landscape. J Zool (1987) 2022. [DOI: 10.1111/jzo.13023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- E. González‐Bernardo
- Biodiversity Research Institute (IMIB, Spanish National Research Council CSIC‐ University of Oviedo‐Principality of Asturias) Mieres Spain
| | - M. d. M. Delgado
- Biodiversity Research Institute (IMIB, Spanish National Research Council CSIC‐ University of Oviedo‐Principality of Asturias) Mieres Spain
| | - D. G. G. Matos
- Biodiversity Research Institute (IMIB, Spanish National Research Council CSIC‐ University of Oviedo‐Principality of Asturias) Mieres Spain
| | - A. Zarzo‐Arias
- Department of Applied Geoinformatics and Spatial Planning Faculty of Environmental Sciences Czech University of Life Sciences Prague Suchdol Praha Czech Republic
- Universidad de Oviedo Oviedo Asturias Spain
- Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (MNCN‐CSIC) 28006 Madrid Spain
| | - A. Morales‐González
- Department of Conservation Biology Estación Biológica de Doñana (EBD‐CSIC) Sevilla Spain
| | - H. Ruiz‐Villar
- Biodiversity Research Institute (IMIB, Spanish National Research Council CSIC‐ University of Oviedo‐Principality of Asturias) Mieres Spain
| | - M. Skuban
- Carpathian Wildlife Society Zvolen Slovakia
- Slovak State Nature Conservancy Banská Bystrica Slovakia
| | - L. Maiorano
- Department of Biology and Biotechnologies “Charles Darwin” University of Rome “La Sapienza” Rome Italy
| | - P. Ciucci
- Department of Biology and Biotechnologies “Charles Darwin” University of Rome “La Sapienza” Rome Italy
| | - J. Balbontín
- Departament of Zoology Faculty of Biology University of Seville Sevilla Spain
| | - V. Penteriani
- Biodiversity Research Institute (IMIB, Spanish National Research Council CSIC‐ University of Oviedo‐Principality of Asturias) Mieres Spain
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Pérez-Girón JC, Díaz-Varela ER, Álvarez-Álvarez P, Hernández Palacios O, Ballesteros F, López-Bao JV. Linking landscape structure and vegetation productivity with nut consumption by the Cantabrian brown bear during hyperphagia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:152610. [PMID: 34963596 DOI: 10.1016/j.scitotenv.2021.152610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/18/2021] [Accepted: 12/18/2021] [Indexed: 06/14/2023]
Abstract
In bears, reproduction is dependent on the body reserves accumulated during hyperphagia. The Cantabrian brown bear mainly feeds on nuts during the hyperphagia period. Understanding how landscape heterogeneity and vegetation productivity in human-dominated landscapes influence the feeding habits of bears may therefore be important for disentangling species-habitat relationships of conservation interest. We determined the spatial patterns of nut consumption by brown bears during the hyperphagia period in relation to landscape structure, characteristics of fruit-producing patches and vegetation productivity. For this purpose, we constructed foraging models based on nut consumption data (obtained by scat analysis), by combining vegetation productivity data, topographical variables and landscape metrics to identify nut foraging patterns during this critical period for bears. The average wooded area of patches where scats were collected and where the nuts that the bears had consumed were produced was larger than that of the corresponding patches where nuts were not produced. For scats collected outside of nut-producing patches, the distance between the scats and the patches was greatest for chestnut-producing patches. Elevation, Gross Primary Production (GPP) and the Aggregation Index (AI) were good predictors of acorn consumption in the models. Good model fits were not obtained for data on chestnut consumption in bears. The findings confirm that brown bears feeding on nuts show a preference for relatively large, highly aggregated patches with a high degree of diversity in the landscape pattern, which may help the bears to remain undetected. The nut prediction model highlights areas of particular importance for brown bears during hyperphagia. The human presence associated with sweet chestnut forest stands or orchards may make bears feel more vulnerable when feeding.
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Affiliation(s)
- José Carlos Pérez-Girón
- Department of Organisms and Systems Biology, Polytechnic School of Mieres, University of Oviedo, E-33600, Mieres, Asturias, Spain.
| | - Emilio Rafael Díaz-Varela
- Research Group on Planning and Management in Complex Adaptive Socio-Ecological Systems (COMPASSES), School of Engineering, University of Santiago de Compostela, E-27002 Lugo, Spain
| | - Pedro Álvarez-Álvarez
- Department of Organisms and Systems Biology, Polytechnic School of Mieres, University of Oviedo, E-33600, Mieres, Asturias, Spain
| | - Orencio Hernández Palacios
- Dirección General del Medio Natural y Planificación Rural, Gobierno del Principado de Asturias, E-33005 Oviedo, Spain
| | | | - José Vicente López-Bao
- Biodiversity Research Institute (CSIC - Oviedo University - Principality of Asturias), University of Oviedo, E-33600 Mieres, Spain
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And yet, migration, population growth or mortality are not balanced among Cantabrian brown bear subpopulations. Reply to Blanco et al (2020). PLoS One 2021; 16:e0256432. [PMID: 34644301 PMCID: PMC8513912 DOI: 10.1371/journal.pone.0256432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 08/06/2021] [Indexed: 11/19/2022] Open
Abstract
In a recent paper, we presented new evidence and provided new insights on the status of Cantabrian brown bear subpopulations, relevant for this species conservation. Namely, we revealed the likely phylogeographic relation between eastern Cantabrian subpopulation and the historical Pyrenean population. We have also detected an asymmetric flow of alleles and individuals from the eastern to the western subpopulation, including seven first-generation male migrants. Based on our results and on those of previous studies, we called the attention to the fact that Eastern Cantabrian brown bears might be taking advantage of increased connectivity to avoid higher human pressure and direct persecution in the areas occupied by the eastern Cantabrian subpopulation. In reply, Blanco et al (2020) [11] have criticized our ecological interpretation of the data presented in our paper. Namely, Blanco and co-authors criticize: (1) the use of the exodus concept in the title and discussion of the paper; (2) the apparent contradiction with source-sink theory; (3) the apparent overlooking of historical demographic data on Cantabrian brown bear and the use of the expression of population decline when referring to eastern subpopulation. Rather than contradicting the long and growing body of knowledge on the two brown bear subpopulations, the results presented in our paper allow a new perspective on the causes of the distinct pace of population growth of the two brown bear subpopulations in the last decades. Here, we reply to the criticisms by: clarifying our ecological interpretation of the results; refocusing the discussion on how the new genetic data suggest that currently, the flow of individuals and alleles is stronger westward, and how it may be linked to direct persecution and killing of brown bears. We provide detailed data on brown bear mortality in the Cantabrian Mountains and show that neither migration, gene flow, population increase nor mortality are balanced among the two subpopulations.
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Does genetic variation on the shy–bold continuum influence carnivore attacks on people? Evidence from the brown bear. ORYX 2021. [DOI: 10.1017/s0030605320000824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
AbstractLittle is known about the heritable behavioural traits of attacks by large carnivores on people. During the last 30 years attacks by brown bears Ursus arctos on people in the Cantabrian Mountains of Spain have been disproportionately concentrated in the eastern subpopulation. Excluding factors such as the existence of a single unusually bold bear, a higher human population density, particular human activities promoting encounters, or clear habitat differences in the area of this subpopulation, we propose that a plausible explanation for the unbalanced geographical attack pattern is that this subpopulation, separated a century earlier from the western subpopulation, may harbour a higher proportion of bolder bears. In the absence of genetic analyses this explanation remains speculative, but supports the hypothesis that genetic variation on the shy–bold continuum may influence attacks of large carnivores on people.
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González-Bernardo E, Bagnasco C, Bombieri G, Zarzo-Arias A, Ruiz-Villar H, Morales-González A, Lamamy C, Ordiz A, Cañedo D, Díaz J, Chamberlain DE, Penteriani V. Rubbing behavior of European brown bears: factors affecting rub tree selectivity and density. J Mammal 2021; 102:468-480. [PMID: 34121953 PMCID: PMC8189685 DOI: 10.1093/jmammal/gyaa170] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 12/03/2020] [Indexed: 11/13/2022] Open
Abstract
Scent-mediated communication is considered the principal communication channel in many mammal species. Compared with visual and vocal communication, odors persist for a longer time, enabling individuals to interact without being in the same place at the same time. The brown bear (Ursus arctos), like other mammals, carries out chemical communication, for example, by means of scents deposited on marking (or rub) trees. In this study, we assessed rub tree selectivity of the brown bear in the predominantly deciduous forests of the Cantabrian Mountains (NW Spain). We first compared the characteristics of 101 brown bear rub trees with 263 control trees. We then analyzed the potential factors affecting the density of rub trees along 35 survey routes along footpaths. We hypothesized that: (1) bears would select particular trees, or tree species, with characteristics that make them more conspicuous; and (2) that bears would select trees located in areas with the highest presence of conspecifics, depending on the population density or the position of the trees within the species' range. We used linear models and generalized additive models to test these hypotheses. Our results showed that brown bears generally selected more conspicuous trees with a preference for birches (Betula spp.). This choice may facilitate the marking and/or detection of chemical signals and, therefore, the effectiveness of intraspecific communication. Conversely, the abundance of rub trees along footpaths did not seem to depend on the density of bear observations or their relative position within the population center or its border. Our results suggest that Cantabrian brown bears select trees based on their individual characteristics and their location, with no influence of characteristics of the bear population itself. Our findings can be used to locate target trees that could help in population monitoring.
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Affiliation(s)
- Enrique González-Bernardo
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, Mieres, Spain
- Pyrenean Institute of Ecology (IPE), C.S.I.C., Avda. Montañana, Zaragoza, Spain
| | - Carlotta Bagnasco
- Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina, Turin, Italy
| | - Giulia Bombieri
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, Mieres, Spain
- Museo delle Scienze, Sezione Zoologia dei Vertebrati, Corso del Lavoro e della Scienza 3, Trento, Italy
| | - Alejandra Zarzo-Arias
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, Mieres, Spain
- Department of Applied Geoinformatics and Spatial Planning, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká, Praha – Suchdol, Czech Republic
| | - Héctor Ruiz-Villar
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, Mieres, Spain
| | - Ana Morales-González
- Estación Biológica de Doñana, C.S.I.C., Department of Conservation Biology, Avda. Americo Vespucio, Sevilla, Spain
| | - Cindy Lamamy
- Gembloux Agro-Bio Tech, Dpt. BIOSE, Liège University, Passage des Déportés, Gembloux, Belgium
| | - Andrés Ordiz
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
| | - David Cañedo
- Consejería de Ordenación del Territorio, Infraestructuras y Medio Ambiente, Dirección General de Biodiversidad, Principado de Asturias, Oviedo, Spain
| | - Juan Díaz
- Consejería de Ordenación del Territorio, Infraestructuras y Medio Ambiente, Dirección General de Biodiversidad, Principado de Asturias, Oviedo, Spain
| | - Daniel E Chamberlain
- Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina, Turin, Italy
| | - Vincenzo Penteriani
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, Mieres, Spain
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Blanco JC, Ballesteros F, Palomero G, López-Bao JV. Not exodus, but population increase and gene flow restoration in Cantabrian brown bear (Ursus arctos) subpopulations. Comment on Gregório et al. 2020. PLoS One 2020; 15:e0240698. [PMID: 33137146 PMCID: PMC7605620 DOI: 10.1371/journal.pone.0240698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/30/2020] [Indexed: 11/25/2022] Open
Abstract
In a genetic study on brown bears (Ursus arctos) in the Cantabrian Mountains, Gregório et al. (2020) interpreted the asymmetrical gene flow they found from the eastern subpopulation towards the western one as an exodus of bears forced to flee from the eastern nucleus “with higher human disturbance and poaching”, concluding that connectivity may be operating as a means for eastern Cantabrian bears to find more suitable territories. In this reply, we maintain that the explanations of Gregorio et al. contradict the source-sink theory and we also present demographic data not considered by these authors showing that the eastern subpopulation is not declining, but persistently increasing. After reviewing the demographic and genetic studies published during the last 20 years, we conclude that the connectivity between the two subpopulations is operating as a route which allows the regular movement of males and the restoration of the gene flow across the whole Cantabrian population.
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Zarzo‐Arias A, Delgado MM, Palazón S, Afonso Jordana I, Bombieri G, González‐Bernardo E, Ordiz A, Bettega C, García‐González R, Penteriani V. Seasonality, local resources and environmental factors influence patterns of brown bear damages: implications for management. J Zool (1987) 2020. [DOI: 10.1111/jzo.12839] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- A. Zarzo‐Arias
- Research Unit of Biodiversity (UMIB CSIC‐UO‐PA) Mieres Spain
| | - M. M. Delgado
- Research Unit of Biodiversity (UMIB CSIC‐UO‐PA) Mieres Spain
| | - S. Palazón
- Fauna and Flora Service, Territory and Sustainability Department Generalitat de Catalunya Barcelona Spain
| | | | - G. Bombieri
- Research Unit of Biodiversity (UMIB CSIC‐UO‐PA) Mieres Spain
- Sezione Zoologia dei Vertebrati Museo delle Scienze Trento Italy
| | | | - A. Ordiz
- Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences Ås Norway
| | - C. Bettega
- Research Unit of Biodiversity (UMIB CSIC‐UO‐PA) Mieres Spain
| | | | - V. Penteriani
- Research Unit of Biodiversity (UMIB CSIC‐UO‐PA) Mieres Spain
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11
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Gregório I, Barros T, Pando D, Morante J, Fonseca C, Ferreira E. Paths for colonization or exodus? New insights from the brown bear (Ursus arctos) population of the Cantabrian Mountains. PLoS One 2020; 15:e0227302. [PMID: 32004321 PMCID: PMC6996475 DOI: 10.1371/journal.pone.0227302] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 12/16/2019] [Indexed: 01/30/2023] Open
Abstract
Over the centuries, the geographical distribution of brown bear (Ursus arctos) across the Iberian Peninsula has been decreasing, with the species currently confined to North Iberia. The Cantabrian brown bear population is one of the smallest in Europe and is structured into two subpopulations, positioned along an east-west axis. Given the current critically endangered status of this population, it is essential to have a clear picture of its within-population genetic patterns and processes. We use a set of three molecular markers (mitochondrial DNA, autosomal microsatellites and sex markers) to clarify the genetic origins and assess the migration patterns and gene flow of the Cantabrian brown bear population. Our results reveal the presence of two different mitochondrial (matrilineal) haplotypes in the Cantabrian population, both belonging to European brown bear clade 1a. The two haplotypes are geographically structured between Eastern (haplotype CanE) and Western Cantabrian (haplotype CanW) subpopulations, which is consistent with the genetic structure previously identified using nuclear markers. Additionally, we show that CanE is closer to the historical Pyrenean (Pyr) haplotype than to CanW. Despite strong structuring at the levels of mtDNA and nuclear loci, there is evidence of bidirectional gene flow and admixture among subpopulations. Gene flow is asymmetrical and significantly more intense from the Eastern to the Western Cantabrian subpopulation. In fact, we only detected first generation male migrants from the Eastern to the Western Cantabrian subpopulation. These results suggest more intense migration from the smaller and more vulnerable Eastern Cantabrian subpopulation towards the larger and more stable Western Cantabrian subpopulation. These new insights are relevant for assessments of on-going conservation measures, namely the role of dispersal corridors and enhanced connectivity. We discuss the importance of complementary conservation measures, such as human-wildlife conflict mitigation and habitat improvement, for the conservation of a viable Cantabrian brown bear population.
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Affiliation(s)
- Inês Gregório
- Department of Biology & CESAM, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
| | - Tânia Barros
- Department of Biology & CESAM, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
| | - Doriana Pando
- Fondo para la Protección de los Animales Salvajes, Santo Adriano, Asturias, Spain
| | - Joaquín Morante
- Fondo para la Protección de los Animales Salvajes, Santo Adriano, Asturias, Spain
| | - Carlos Fonseca
- Department of Biology & CESAM, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
| | - Eduardo Ferreira
- Department of Biology & CESAM, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
- * E-mail:
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Relevance of the Cell Neighborhood Size in Landscape Metrics Evaluation and Free or Open Source Software Implementations. ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION 2019. [DOI: 10.3390/ijgi8120586] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Landscape metrics constitute one of the main tools for the study of the changes of the landscape and of the ecological structure of a region. The most popular software for landscape metrics evaluation is FRAGSTATS, which is free to use but does not have free or open source software (FOSS). Therefore, FOSS implementations, such as QGIS’s LecoS plugin and GRASS’ r.li modules suite, were developed. While metrics are defined in the same way, the “cell neighborhood” parameter, specifying the configuration of the moving window used for the analysis, is managed differently: FRAGSTATS can use values of 4 or 8 (8 is default), LecoS uses 8 and r.li 4. Tests were performed to evaluate the landscape metrics variability depending on the “cell neighborhood” values: some metrics, such as “edge density” and “landscape shape index”, do not change, other, for example “patch number”, “patch density”, and “mean patch area”, vary up to 100% for real maps and 500% for maps built to highlight this variation. A review of the scientific literature was carried out to check how often the value of the “cell neighborhood” parameter is explicitly declared. A method based on the “aggregation index” is proposed to estimate the effect of the uncertainty on the “cell neighborhood” parameter on landscape metrics for different maps.
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