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Fuzessy L, Pavoine S, Cardador L, Maspons J, Sol D. Loss of species and functions in a deforested megadiverse tropical forest. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024:e14250. [PMID: 38477227 DOI: 10.1111/cobi.14250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 12/23/2023] [Accepted: 01/04/2024] [Indexed: 03/14/2024]
Abstract
Tropical species richness is threatened by habitat degradation associated with land-use conversion, yet the consequences for functional diversity remain little understood. Progress has been hindered by difficulties in obtaining comprehensive species-level trait information to characterize entire assemblages and insufficient appreciation that increasing land-cover heterogeneity potentially compensates for species loss. We examined the impacts of tropical deforestation associated with land-use heterogeneity on bird species richness, functional redundancy, functional diversity, and associated components (i.e., alpha diversity, species dissimilarity, and interaction strength of the relationship between abundance and functional dissimilarity). We analyzed over 200 georeferenced bird assemblages in the Atlantic Forest of Brazil. We characterized the functional role of the species of each assemblage and modeled biodiversity metrics as a function of forest cover and land-cover heterogeneity. Replacement of native Atlantic Forest with a mosaic of land uses (e.g., agriculture, pastures, and urbanization) reduced bird species richness in a nonrandom way. Core forest species, or species considered sensitive to edges, tended to be absent in communities in heterogenous environments. Overall, functional diversity and functional redundancy of bird species were not affected by forest loss. However, birds in highly heterogenous habitats were functionally distinct from birds in forest, suggesting a shift in community composition toward mosaic-exclusive species led by land-cover heterogeneity. Threatened species of the Atlantic Forest did not seem to tolerate degraded and heterogeneous environments; they remained primarily in areas with large forest tracts. Our results shed light on the complex effects of native forest transformation to mosaics of anthropogenic landscapes and emphasize the importance of considering the effects of deforestation and land-use heterogeneity when assessing deforestation effects on Neotropical biodiversity.
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Affiliation(s)
- Lisieux Fuzessy
- CREAF, Bellaterra (Cerdanyola del Vallès), Barcelona, Spain
- Bioscience Institute, São Paulo State University (UNESP), Rio Claro, Brazil
| | - Sandrine Pavoine
- Centre d'Ecologie et des Sciences de la Conservation (CESCO), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, Paris, France
| | - Laura Cardador
- CREAF, Bellaterra (Cerdanyola del Vallès), Barcelona, Spain
| | - Joan Maspons
- CREAF, Bellaterra (Cerdanyola del Vallès), Barcelona, Spain
| | - Daniel Sol
- CREAF, Bellaterra (Cerdanyola del Vallès), Barcelona, Spain
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2
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Şekercioğlu ÇH, Fullwood MJ, Cerling T, Brenes FO, Daily GC, Ehrlich PR, Chamberlain P, Newsome SD. Using stable isotopes to measure the dietary responses of Costa Rican forest birds to agricultural countryside. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1086616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023] Open
Abstract
How human modification of native habitats changes the feeding patterns and nutritional ecology of tropical birds is critical to conserving avian biodiversity, but tropical bird diets are laborious to investigate using the traditional methods of diet analysis. Stable isotope analysis provides a cost-effective and efficient proxy to identify general foraging patterns, especially when dietary shifts spanning multiple trophic levels have occurred due to ecosystem disturbance or transformation. To characterize the diets of forest bird species that persist in tropical agricultural countryside, we compared feather carbon (δ13C) and nitrogen (δ15N) isotope values of four species caught and radio-tracked in a 270 hectare forest reserve, smaller forest remnants (including mature forest, secondary forest, and riparian strips), and coffee plantations in mid-elevation (ca. 800–1,400 m) southern Costa Rica. Bird habitat choice had a significant effect on diet composition as revealed by δ13C and δ15N values. Three of the four species studied showed evidence of significantly reduced consumption of invertebrates in coffee plantations, with the isotope values of two species (Tangara icterocephala and Turdus assimilis) indicating, by comparison, nearly a doubling of invertebrate consumption in forest remnants. Our results suggest that coffee plantations are deficient in invertebrates preferred by forest generalist birds that forage in both native forest remnants and coffee plantations. In this region, typical of mountainous American tropics, small forest remnants and a larger forest reserve provide critical dietary resources for native forest birds that utilize the agricultural countryside.
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3
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Ngo Bieng MA, Delgado-Rodríguez D, Vilchez-Mendoza S, López-Sampson A, García E, Sepúlveda N, Somarriba E. Tree diversity in a tropical agricultural-forest mosaic landscape in Honduras. Sci Rep 2022; 12:18544. [PMID: 36329120 PMCID: PMC9633691 DOI: 10.1038/s41598-022-21280-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 09/26/2022] [Indexed: 11/05/2022] Open
Abstract
Biodiversity decline in the tropics requires the implementation of comprehensive landscape management where agricultural systems are necessarily an integral element of biodiversity conservation. This study evaluates the potential for taxonomic biodiversity conservation within an intensive livestock-agricultural-forest mosaic landscape in Catacamas, Honduras. Tree sampling was performed in 448 plots set up within different forest and agricultural land uses: secondary forests, agroforestry coffee plantations, agriculture, pastures, live fences and riparian forest. All trees with a minimum diameter at breast height of 10 cm were identified and measured. We characterized their tree structure and diversity, and compared tree diversity between the different uses. The results indicate a high degree of tree species diversity: 375 species identified, belonging to 74 families among the 15,096 trees inventoried across 84.2 hectares, including many rare species (40% of the species registered three individuals or fewer). Biodiversity indices for agroforestry coffee were found equivalent to those for natural secondary forests in the Catacamas landscape. Combining biodiversity conservation and agricultural production is possible in human-pressured tropical landscapes through tree cover maintenance. Enrichment practices combining local producers and technical knowledge may improve tree diversity in agricultural landscapes by prioritizing a mix of forest and introduced tree species (rare and with multiple uses).
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Affiliation(s)
- Marie Ange Ngo Bieng
- grid.24753.370000 0001 2206 525XCATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica ,grid.121334.60000 0001 2097 0141CIRAD, Université de Montpellier, UR Forêts & Sociétés, 34398 Montpellier, France
| | - Diego Delgado-Rodríguez
- grid.24753.370000 0001 2206 525XCATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
| | - Sergio Vilchez-Mendoza
- grid.24753.370000 0001 2206 525XCATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
| | - Arlene López-Sampson
- grid.24753.370000 0001 2206 525XCATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
| | - Edwin García
- grid.24753.370000 0001 2206 525XCATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
| | - Norvin Sepúlveda
- grid.24753.370000 0001 2206 525XCATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
| | - Eduardo Somarriba
- grid.24753.370000 0001 2206 525XCATIE - Centro Agronómico Tropical de Investigación y Enseñanza, 30501 Turrialba, Costa Rica
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4
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Monge O, Schulze CH, Dullinger S, Fusani L, Maggini I. Unshaded coffee imposes a heavier load on thermoregulation than shaded coffee for birds in a tropical mountainous region. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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5
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Response of avian communities to edges of tropical montane forests: Implications for the future of endemic habitat specialists. Glob Ecol Conserv 2021. [DOI: 10.1016/j.gecco.2021.e01776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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6
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Hamer KC, Sasu MA, Ofosuhene L, Asare R, Ossom B, Parr CL, Scriven SA, Asante W, Addico R, Hill JK. Proximity to forest mediates trade‐offs between yields and biodiversity of birds in oil palm smallholdings. Biotropica 2021. [DOI: 10.1111/btp.12997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Michael A. Sasu
- School of Biology University of Leeds Leeds UK
- Nature Conservation Research Centre Accra Ghana
| | - Linda Ofosuhene
- School of Biology University of Leeds Leeds UK
- Nature Conservation Research Centre Accra Ghana
| | | | | | - Catherine L. Parr
- Department of Earth, Ocean and Ecological Sciences University of Liverpool Liverpool UK
| | - Sarah A. Scriven
- Leverhulme Centre for Anthropocene Biodiversity Department of Biology University of York York UK
| | - Winston Asante
- Department of Silviculture and Forest Management Kwame Nkrumah University of Science and Technology Kumasi Ghana
| | | | - Jane K. Hill
- Leverhulme Centre for Anthropocene Biodiversity Department of Biology University of York York UK
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7
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Blount JD, Horns JJ, Kittelberger KD, Neate-Clegg MHC, Şekercioğlu ÇH. Avian Use of Agricultural Areas as Migration Stopover Sites: A Review of Crop Management Practices and Ecological Correlates. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.650641] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
An estimated 17% of migratory bird species are threatened or near threatened with extinction. This represents an enormous potential loss of biodiversity and cost to human societies due to the economic benefits that birds provide through ecosystem services and ecotourism. Conservation of migratory bird species presents many unique challenges, as these birds rely on multiple geographically distinct habitats, including breeding grounds, non-breeding grounds, and stopover sites during migration. In particular, stopover habitats are seldom studied relative to breeding and non-breeding habitats, despite their importance as refueling stations for migratory birds. In this study, we summarize the current research on the use of temporary primary crops by birds during migration and we assess the species characteristics and agricultural practices most often associated with the use of cropland as stopover habitat. First, we conducted a systematic review of the literature to document the effects various farming practices and crop types have on the abundance and diversity of migratory birds using agricultural areas for stopovers. Second, we analyzed the ecological correlates of bird species in the Northern Hemisphere that predict which species may use these areas while migrating. We ran a GLMM to test whether primary diet, diet breadth, primary habitat, habitat breadth, or realm predicted stopover use of agricultural areas. Our review suggests that particular crop types (principally rice, corn, and sunflower), as well as farming practices that result in higher non-cultivated plant diversity, encourage the use of agricultural areas by migrating birds. We found that cropland is used as stopover habitat by bird species that can utilize a large breadth of habitats, as well as species with preferences for habitat similar in structure to agricultural areas.
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8
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Edwards FA, Massam MR, Cosset CCP, Cannon PG, Haugaasen T, Gilroy JJ, Edwards DP. Sparing land for secondary forest regeneration protects more tropical biodiversity than land sharing in cattle farming landscapes. Curr Biol 2021; 31:1284-1293.e4. [PMID: 33482111 DOI: 10.1016/j.cub.2020.12.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/19/2020] [Accepted: 12/21/2020] [Indexed: 11/29/2022]
Abstract
Effectively managing farming to meet food demand is vital for the future of biodiversity.1,2 Increasing yields on existing farmland can allow the abandonment (sparing) of low-yielding areas that subsequently recover as secondary forest.2-5 A key question is whether such "secondary sparing" conserves biodiversity more effectively than retaining wildlife-friendly habitat within farmland ("land sharing"). Focusing on the Colombian Choco-Andes, a global hotspot of threatened biodiversity,6 and on cattle farming, we examined the outcomes of secondary sparing and land sharing via simulated scenarios that maintained constant landscape-wide production and equal within-pasture yield: (1) for species and functional diversity of dung beetles and birds; (2) for avian phylogenetic diversity; and (3) across different stages of secondary forest regeneration, relative to spared primary forests. Sparing older secondary forests (15-30 years recovery) promotes substantial species, functional, and phylogenetic (birds only) diversity benefits for birds and dung beetles compared to land sharing. Species of conservation concern had higher occupancy estimates under land-sparing compared to land-sharing scenarios. Spared secondary forests accumulated equivalent diversity to primary forests for dung beetles within 15 years and within 15-30 years for birds, highlighting the need for longer term protection to maximize the biodiversity gains of secondary sparing. Promoting the recovery and protection of large expanses of secondary forests under the land-sparing model provides a critical mechanism for protecting tropical biodiversity, with important implications for concurrently assisting in the delivery of global targets to restore 350 million hectares of forested landscapes.7,8.
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Affiliation(s)
- Felicity A Edwards
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
| | - Mike R Massam
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Cindy C P Cosset
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Patrick G Cannon
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Torbjørn Haugaasen
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
| | - James J Gilroy
- School of Environmental Science, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - David P Edwards
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
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9
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Stouffer PC, Jirinec V, Rutt CL, Bierregaard RO, Hernández-Palma A, Johnson EI, Midway SR, Powell LL, Wolfe JD, Lovejoy TE. Long-term change in the avifauna of undisturbed Amazonian rainforest: ground-foraging birds disappear and the baseline shifts. Ecol Lett 2020; 24:186-195. [PMID: 33103837 DOI: 10.1111/ele.13628] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/06/2020] [Accepted: 09/14/2020] [Indexed: 01/10/2023]
Abstract
How are rainforest birds faring in the Anthropocene? We use bird captures spanning > 35 years from 55 sites within a vast area of intact Amazonian rainforest to reveal reduced abundance of terrestrial and near-ground insectivores in the absence of deforestation, edge effects or other direct anthropogenic landscape change. Because undisturbed forest includes far fewer terrestrial and near-ground insectivores than it did historically, today's fragments and second growth are more impoverished than shown by comparisons with modern 'control' sites. Any goals for bird community recovery in Amazonian second growth should recognise that a modern bird community will inevitably differ from a baseline from > 35 years ago. Abundance patterns driven by landscape change may be the most conspicuous manifestation of human activity, but biodiversity declines in undisturbed forest represent hidden losses, possibly driven by climate change, that may be pervasive in intact Amazonian forests and other systems considered to be undisturbed.
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Affiliation(s)
- Philip C Stouffer
- School of Renewable Natural Resources, Louisiana State University AgCenter and Louisiana State University, Baton Rouge, LA, 70803, USA.,Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil
| | - Vitek Jirinec
- School of Renewable Natural Resources, Louisiana State University AgCenter and Louisiana State University, Baton Rouge, LA, 70803, USA.,Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil
| | - Cameron L Rutt
- School of Renewable Natural Resources, Louisiana State University AgCenter and Louisiana State University, Baton Rouge, LA, 70803, USA.,Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil.,Department of Biology, George Mason University, Fairfax, VA, 22030, USA
| | - Richard O Bierregaard
- Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil
| | - Angélica Hernández-Palma
- School of Renewable Natural Resources, Louisiana State University AgCenter and Louisiana State University, Baton Rouge, LA, 70803, USA.,Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil.,Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, Avenida Paseo Bolívar 16-20, Bogotá, D.C, Colombia
| | - Erik I Johnson
- School of Renewable Natural Resources, Louisiana State University AgCenter and Louisiana State University, Baton Rouge, LA, 70803, USA.,Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil.,National Audubon Society, 5615 Corporate Blvd. #600b, Baton Rouge, LA, 70808, USA
| | - Stephen R Midway
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Luke L Powell
- School of Renewable Natural Resources, Louisiana State University AgCenter and Louisiana State University, Baton Rouge, LA, 70803, USA.,Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil.,School of Biological and Biomedical Sciences, Durham University, Durham, DH1 3LE, UK
| | - Jared D Wolfe
- School of Renewable Natural Resources, Louisiana State University AgCenter and Louisiana State University, Baton Rouge, LA, 70803, USA.,Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil.,College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, 49931, USA
| | - Thomas E Lovejoy
- Biological Dynamics of Forest Fragments Project, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69011, Brazil.,Department of Environmental Science and Policy, George Mason University, Fairfax, VA, 22030-4444, USA
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10
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Abstract
The coffee sector is working towards sector-wide commitments for sustainable production. Yet, knowledge of where coffee is cultivated and its environmental impact remains limited, in part due to the challenges of mapping coffee using satellite remote sensing. We recognize the urgency to capitalize on recent technological advances to improve remote sensing methods and generate more accurate, reliable, and scalable approaches to coffee mapping. In this study, we provide a systematic review of satellite-based approaches to mapping coffee extent, which produced 43 articles in the peer-reviewed and gray literature. We outline key considerations for employing effective approaches, focused on the need to balance data affordability and quality, classification complexity and accuracy, and generalizability and site-specificity. We discuss research opportunities for improved approaches by leveraging the recent expansion of diverse satellite sensors and constellations, optical/Synthetic Aperture Radar data fusion approaches, and advances in cloud computing and deep learning algorithms. We highlight the need for differentiating between production systems and the need for research in important coffee-growing geographies. By reviewing the range of techniques successfully used to map coffee extent, we provide technical recommendations and future directions to enable accurate and scalable coffee maps.
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11
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Li HD, Tang L, Jia C, Holyoak M, Fründ J, Huang X, Xiao Z. The functional roles of species in metacommunities, as revealed by metanetwork analyses of bird-plant frugivory networks. Ecol Lett 2020; 23:1252-1262. [PMID: 32436358 DOI: 10.1111/ele.13529] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/30/2020] [Accepted: 04/09/2020] [Indexed: 01/12/2023]
Abstract
Understanding how biodiversity and interaction networks change across environmental gradients is a major challenge in ecology. We integrated metacommunity and metanetwork perspectives to test species' functional roles in bird-plant frugivory interactions in a fragmented forest landscape in Southwest China, with consequences for seed dispersal. Availability of fruit resources both on and under trees created vertical feeding stratification for frugivorous birds. Bird-plant interactions involving birds feeding only on-the-tree or both on and under-the-tree (shared) had a higher centrality and contributed more to metanetwork organisation than interactions involving birds feeding only under-the-tree. Moreover, bird-plant interactions associated with large-seeded plants disproportionately contributed to metanetwork organisation and centrality. Consequently, on-the-tree and shared birds contributed more to metanetwork organisation whereas under-the-tree birds were more involved in local processes. We would expect that species' roles in the metanetwork will translate into different conservation values for maintaining functioning of seed-dispersal networks.
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Affiliation(s)
- Hai-Dong Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 10049, China
| | - Linfang Tang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China.,Key Laboratory of Zoological Systematics and Evolution, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Chenxi Jia
- State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China.,Key Laboratory of Zoological Systematics and Evolution, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Marcel Holyoak
- Department of Environmental Science and Policy, University of California, 1 Shields Ave, Davis, CA, 95616, USA
| | - Jochen Fründ
- Biometry and Environmental System Analysis, University of Freiburg, Tennenbacherstr. 4, 79106, Freiburg, Germany
| | - Xiaoqun Huang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Zhishu Xiao
- State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 10049, China
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12
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Abstract
This study visualizes and quantifies extant publications of rural landscape research (RLR) in Web of Science using CiteSpace for a wide range of research topics, from a multi-angle analysis of the overall research profile, while providing a method and approach for quantitative analysis of massive literature data. First, it presents the number of papers published, subject distribution, author network, the fundamental condition of countries, and research organizations involved in RLR through network analysis. Second, it identifies the high-frequency and high betweenness-centrality values of the basic research content of RLR through keyword co-occurrence analysis and keyword time zones. Finally, it identifies research fronts and trending topics of RLR in the decade from 2009 to 2018 by using co-citation clustering, and noun-term burst detection. The results show that basic research content involves protection, management, biodiversity, and land use. Five clearer research frontier pathways and top 20 research trending topics are extracted to show diversified research branch development. All this provides the reader with a general preliminary grasp of RLR, showing that cooperation and analysis involving multiple disciplines, specialties, and angles will become a dominant trend in the field.
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13
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Emer C, Jordano P, Pizo MA, Ribeiro MC, Silva FR, Galetti M. Seed dispersal networks in tropical forest fragments: Area effects, remnant species, and interaction diversity. Biotropica 2019. [DOI: 10.1111/btp.12738] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Carine Emer
- Departamento de Ecologia Instituto de Biociências Universidade Estadual Paulista (UNESP) Rio Claro Brazil
| | - Pedro Jordano
- Integrative Ecology Group Estación Biológica de Doñana (EBD‐CSIC) Consejo Superior de Investigaciones Científicas Sevilla Spain
| | - Marco A. Pizo
- Departamento de Zoologia Universidade Estadual Paulista (UNESP) Rio Claro Brazil
| | - Milton C. Ribeiro
- Departamento de Ecologia Instituto de Biociências Universidade Estadual Paulista (UNESP) Rio Claro Brazil
| | - Fernanda R. Silva
- Instituto de Biologia Universidade de Campinas (UNICAMP) Campinas Brazil
| | - Mauro Galetti
- Departamento de Ecologia Instituto de Biociências Universidade Estadual Paulista (UNESP) Rio Claro Brazil
- Department of Biology University of Miami Coral Gables FL USA
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14
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Sánchez‐Clavijo LM, Bayly NJ, Quintana‐Ascencio PF. Habitat selection in transformed landscapes and the role of forest remnants and shade coffee in the conservation of resident birds. J Anim Ecol 2019; 89:553-564. [DOI: 10.1111/1365-2656.13108] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 08/22/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Lina María Sánchez‐Clavijo
- Department of Biology University of Central Florida Orlando FL USA
- Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Bogotá Colombia
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15
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Heath SK, Long RF. Multiscale habitat mediates pest reduction by birds in an intensive agricultural region. Ecosphere 2019. [DOI: 10.1002/ecs2.2884] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Sacha K. Heath
- Graduate Group in Ecology and Department of Environmental Science and Policy University of California, Davis One Shields Avenue Davis California 95616USA
| | - Rachael F. Long
- University of California Cooperative Extension 70 Cottonwood Street Woodland California 95695 USA
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16
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Frishkoff LO, Karp DS. Species-specific responses to habitat conversion across scales synergistically restructure Neotropical bird communities. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2019; 29:e01910. [PMID: 31107576 DOI: 10.1002/eap.1910] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 01/31/2019] [Accepted: 03/29/2019] [Indexed: 06/09/2023]
Abstract
Ecologists are increasingly exploring methods for preserving biodiversity in agricultural landscapes. Yet because species vary in how they respond to habitat conversion, ecological communities in agriculture and more natural habitats are often distinct. Unpacking the heterogeneity in species responses to habitat conversion will be essential for predicting and mitigating community shifts. Here, we analyze two years of bird censuses at 150 sites across gradients of local land cover, landscape forest amount and configuration, and regional precipitation in Costa Rica to holistically characterize species responses to habitat conversion. Specifically, we used Poisson-binomial mixture models to (1) delineate groups of species that respond similarly to environmental gradients, (2) explore the relative importance of local vs. landscape-level habitat conversion, and (3) determine how landscape context influences species' local habitat preferences. We found that species fell into six groups: habitat generalists, abundant and rare forest specialists, and three groups of agricultural specialists that differed in their responses to landscape forest cover, fragmentation, and regional precipitation. Birds were most sensitive to local forest cover, but responses were contingent on landscape context. Specifically, forest specialists benefitted most when local forest cover increased in forested landscapes, while habitat generalists exhibited compensatory dynamics, peaking at sites with either local or landscape-level forest, but not both. Our study demonstrates that species responses to habitat conversion are complex but predictable. Characterizing species-level responses to environmental gradients represents a viable approach for forecasting the winners and losers of global change and designing interventions to minimize the ongoing restructuring of Earth's biota.
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Affiliation(s)
- Luke O Frishkoff
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019, USA
| | - Daniel S Karp
- Department of Wildlife, Fish, and Conservation Biology, University of California, Davis, California, 95616, USA
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17
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Countryside Biogeography: the Controls of Species Distributions in Human-Dominated Landscapes. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s40823-019-00037-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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18
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Cannon PG, Gilroy JJ, Tobias JA, Anderson A, Haugaasen T, Edwards DP. Land-sparing agriculture sustains higher levels of avian functional diversity than land sharing. GLOBAL CHANGE BIOLOGY 2019; 25:1576-1590. [PMID: 30793430 DOI: 10.1111/gcb.14601] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 12/05/2018] [Accepted: 01/15/2019] [Indexed: 06/09/2023]
Abstract
The ecological impacts of meeting rising demands for food production can potentially be mitigated by two competing land-use strategies: off-setting natural habitats through intensification of existing farmland (land sparing), or elevating biodiversity within the agricultural matrix via the integration of "wildlife-friendly" habitat features (land sharing). However, a key unanswered question is whether sparing or sharing farming would best conserve functional diversity, which can promote ecosystem stability and resilience to future land-use change. Focusing on bird communities in tropical cloud forests of the Colombian Andes, we test the performance of each strategy in conserving functional diversity. We show that multiple components of avian functional diversity in farmland are positively related to the proximity and extent of natural forest. Using landscape and community simulations, we also show that land-sparing agriculture conserves greater functional diversity and predicts higher abundance of species supplying key ecological functions than land sharing, with sharing becoming progressively inferior with increasing isolation from remnant forest. These results suggest low-intensity agriculture is likely to conserve little functional diversity unless large blocks of adjacent natural habitat are protected, consistent with land sparing. To ensure the retention of functionally diverse ecosystems, we urgently need to implement mechanisms for increasing farmland productivity whilst protecting spared land.
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Affiliation(s)
- Patrick G Cannon
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - James J Gilroy
- School of Environmental Sciences, University of East Anglia, Norwich, Norfolk, UK
| | - Joseph A Tobias
- Department of Life Sciences, Imperial College London, Ascot, UK
| | - Alex Anderson
- Faculty of Environmental Sciences and Natural Resource Management (MINA), Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Torbjørn Haugaasen
- Faculty of Environmental Sciences and Natural Resource Management (MINA), Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - David P Edwards
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
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19
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Long-term declines in bird populations in tropical agricultural countryside. Proc Natl Acad Sci U S A 2019; 116:9903-9912. [PMID: 31036662 DOI: 10.1073/pnas.1802732116] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Tropical agriculture is a major driver of biodiversity loss, yet it can provide conservation opportunities, especially where protected areas are inadequate. To investigate the long-term biodiversity capacity of agricultural countryside, we quantified bird population trends in Costa Rica by mist netting 57,255 birds of 265 species between 1999 and 2010 in sun coffee plantations, riparian corridors, secondary forests, forest fragments, and primary forest reserves. More bird populations (69) were declining than were stable (39) or increasing (4). Declines were common in resident, insectivorous, and more specialized species. There was no relationship between the species richness of a habitat and its conservation value. High-value forest bird communities were characterized by their distinct species composition and habitat and dietary functional signatures. While 49% of bird species preferred forest to coffee, 39% preferred coffee to forest and 12% used both habitats, indicating that coffee plantations have some conservation value. Coffee plantations, although lacking most of the forest specialists, hosted 185 bird species, had the highest capture rates, and supported increasing numbers of some forest species. Coffee plantations with higher tree cover (7% vs. 13%) had more species with increasing capture rates, twice as many forest specialists, and half as many nonforest species. Costa Rican countryside habitats, especially those with greater tree cover, host many bird species and are critical for connecting bird populations in forest remnants. Diversified agricultural landscapes can enhance the biodiversity capacity of tropical countryside, but, for the long-term persistence of all forest bird species, large (>1,000 ha) protected areas are essential.
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20
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Pfeifer M, Boyle MJW, Dunning S, Olivier PI. Forest floor temperature and greenness link significantly to canopy attributes in South Africa's fragmented coastal forests. PeerJ 2019; 7:e6190. [PMID: 30648017 PMCID: PMC6330204 DOI: 10.7717/peerj.6190] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 11/30/2018] [Indexed: 11/20/2022] Open
Abstract
Tropical landscapes are changing rapidly due to changes in land use and land management. Being able to predict and monitor land use change impacts on species for conservation or food security concerns requires the use of habitat quality metrics, that are consistent, can be mapped using above-ground sensor data and are relevant for species performance. Here, we focus on ground surface temperature (Thermalground) and ground vegetation greenness (NDVIdown) as potentially suitable metrics of habitat quality. Both have been linked to species demography and community structure in the literature. We test whether they can be measured consistently from the ground and whether they can be up-scaled indirectly using canopy structure maps (Leaf Area Index, LAI, and Fractional vegetation cover, FCover) developed from Landsat remote sensing data. We measured Thermalground and NDVIdown across habitats differing in tree cover (natural grassland to forest edges to forests and tree plantations) in the human-modified coastal forested landscapes of Kwa-Zulua Natal, South Africa. We show that both metrics decline significantly with increasing canopy closure and leaf area, implying a potential pathway for upscaling both metrics using canopy structure maps derived using earth observation. Specifically, our findings suggest that opening forest canopies by 20% or decreasing forest canopy LAI by one unit would result in increases of Thermalground by 1.2 °C across the range of observations studied. NDVIdown appears to decline by 0.1 in response to an increase in canopy LAI by 1 unit and declines nonlinearly with canopy closure. Accounting for micro-scale variation in temperature and resources is seen as essential to improve biodiversity impact predictions. Our study suggests that mapping ground surface temperature and ground vegetation greenness utilising remotely sensed canopy cover maps could provide a useful tool for mapping habitat quality metrics that matter to species. However, this approach will be constrained by the predictive capacity of models used to map field-derived forest canopy attributes. Furthermore, sampling efforts are needed to capture spatial and temporal variation in Thermalground within and across days and seasons to validate the transferability of our findings. Finally, whilst our approach shows that surface temperature and ground vegetation greenness might be suitable habitat quality metric used in biodiversity monitoring, the next step requires that we map demographic traits of species of different threat status onto maps of these metrics in landscapes differing in disturbance and management histories. The derived understanding could then be exploited for targeted landscape restoration that benefits biodiversity conservation at the landscape scale.
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Affiliation(s)
- Marion Pfeifer
- Modelling, Evidence & Policy Group, SNES, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Michael J W Boyle
- Forest Ecology and Conservation Group, Silwood Park Campus, Imperial College London, Ascot, Berkshire, United Kingdom
| | - Stuart Dunning
- School of Geography, Politics and Sociology, Newcastle University, Newcastle Upon Tyne, United Kingdom
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21
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Elsen PR, Ramesh K, Wilcove DS. Conserving Himalayan birds in highly seasonal forested and agricultural landscapes. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2018; 32:1313-1324. [PMID: 29855078 DOI: 10.1111/cobi.13145] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 04/05/2018] [Accepted: 05/25/2018] [Indexed: 06/08/2023]
Abstract
The Himalayas are a global biodiversity hotspot threatened by widespread agriculture and pasture expansion. To determine the impact of these threats on biodiversity and to formulate appropriate conservation strategies, we surveyed birds along elevational gradients in primary forest and in human-dominated lands spanning a gradient of habitat alteration, including forest-agriculture mosaics, mixed agriculture mosaics, and pasture. We surveyed birds during the breeding season and in winter to account for pronounced seasonal migrations. Bird abundance and richness in forest-agriculture and mixed agriculture mosaics were equal to or greater than in primary forest and greater than in pasture at local and landscape scales during both seasons. Pasture had greater abundance and richness of birds in winter than primary forest, but richness was greater in primary forest at the landscape scale during the breeding season. All 4 land-use types held unique species, suggesting that all must be retained in the landscape to conserve the entire avifauna. Our results suggest forest-agriculture and mixed agriculture mosaics are particularly important for sustaining Himalayan bird communities during winter and primary forests are vital for sustaining Himalayan bird communities during the breeding season. Further conversion of forest-agriculture and mixed agriculture mosaics to pasture would likely result in significant biodiversity losses that would disproportionately affect breeding species. To ensure comprehensive conservation, strategies in the western Himalayas must balance the protection of intact primary forest with the minimization of pasture expansion.
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Affiliation(s)
- Paul R Elsen
- Woodrow Wilson School, Princeton University, Princeton, NJ, 08544, U.S.A
| | | | - David S Wilcove
- Woodrow Wilson School, Princeton University, Princeton, NJ, 08544, U.S.A
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22
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Neate-Clegg MHC, Jones SEI, Burdekin O, Jocque M, Şekercioğlu ÇH. Elevational changes in the avian community of a Mesoamerican cloud forest park. Biotropica 2018. [DOI: 10.1111/btp.12596] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Montague H. C. Neate-Clegg
- Department of Biology; University of Utah; 257 S 1400 E Salt Lake City UT 84112 USA
- Operation Wallacea Ltd.; Wallace House, Old Bolingbroke Spilsby Lincolnshire PE23 4EX UK
| | - Samuel E. I. Jones
- Operation Wallacea Ltd.; Wallace House, Old Bolingbroke Spilsby Lincolnshire PE23 4EX UK
- School of Biological Sciences; Royal Holloway; University of London; Egham Surrey TW20 0EX UK
| | - Oliver Burdekin
- Operation Wallacea Ltd.; Wallace House, Old Bolingbroke Spilsby Lincolnshire PE23 4EX UK
- burdGIS; Unit G37b; Market Walk Wakefield West Yorkshire WF1 1QR UK
| | - Merlijn Jocque
- Operation Wallacea Ltd.; Wallace House, Old Bolingbroke Spilsby Lincolnshire PE23 4EX UK
- Aquatic and Terrestrial Ecology (ATECO); Royal Belgian Institute of Natural Sciences (RBINS); Vautierstraat 29 1000 Brussels Belgium
| | - Çağan Hakkı Şekercioğlu
- Department of Biology; University of Utah; 257 S 1400 E Salt Lake City UT 84112 USA
- Koç University; Rumelifeneri Istanbul Sarıyer Turkey
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23
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Latta SC, Brouwer NL, Mejía DA, Paulino MM. Avian community characteristics and demographics reveal how conservation value of regenerating tropical dry forest changes with forest age. PeerJ 2018; 6:e5217. [PMID: 30018861 PMCID: PMC6044266 DOI: 10.7717/peerj.5217] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 06/21/2018] [Indexed: 11/20/2022] Open
Abstract
Expansion of secondary forests following the abandonment of agriculture may have important implications for bird conservation, but few studies have examined the dynamics of this process. We studied bird use of a chronosequence of differently-aged abandoned pastures regenerating to dry forest to better understand how the value of these habitats to birds changes over time. In a five year study on Hispaniola, we recorded 7,315 net captures of 60 species of landbirds in sites that began the study at two, five, 10, and 20 years post-abandonment, and in mature native dry forest. Twenty-five species made up 97% of all net captures. Highest capture rates were in the two youngest sites. These early-successional habitats had many over-wintering Neotropical migrants; among residents, granivores and frugivores predominated. In contrast, both the twenty-year-old and mature forest sites had few migrants, more resident insectivores and omnivorous species, and a greater proportion of endemics. Age and sex ratios, body condition and site persistence suggest early successional sites were sub-optimal for most over-wintering migrants, but habitat improved with age for three migratory species; results for permanent residents varied among species. Remnant trees and understory shrubs in the agroecological matrix likely contributed to avian diversity in regenerating dry forest sites, and proximity to mature forest also likely affected the diversity and abundance of birds in regenerating habitat. Our study shows that regenerating forests do not fully compensate for loss of mature dry forest habitat, even after 24 years of regeneration; natural restoration of complex microhabitats in dry forest sites converted to agriculture may take decades or longer. The highest value of regenerating forests may be as habitat for some over-wintering Neotropical migrants, and in creating a buffer zone that enhances biodiversity conservation by re-integrating these lands into the protected tracts of mature forest needed by the islands more unique and endemic bird species.
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Affiliation(s)
- Steven C Latta
- Department of Conservation and Field Research, National Aviary, Pittsburgh, PA, United States of America
| | - Nathan L Brouwer
- Department of Conservation and Field Research, National Aviary, Pittsburgh, PA, United States of America
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24
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Neam KD, Lacher TE. Multi-scale effects of habitat structure and landscape context on a vertebrate with limited dispersal ability (the brown-throated sloth, Bradypus variegatus
). Biotropica 2018. [DOI: 10.1111/btp.12540] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kelsey D. Neam
- Department of Wildlife and Fisheries Sciences; Texas A&M University; College Station TX 77843 USA
- Global Wildlife Conservation; Austin TX 78767 USA
| | - Thomas E. Lacher
- Department of Wildlife and Fisheries Sciences; Texas A&M University; College Station TX 77843 USA
- Global Wildlife Conservation; Austin TX 78767 USA
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25
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Chang CH, Karanth KK, Robbins P. Birds and beans: Comparing avian richness and endemism in arabica and robusta agroforests in India's Western Ghats. Sci Rep 2018; 8:3143. [PMID: 29453390 PMCID: PMC5816607 DOI: 10.1038/s41598-018-21401-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 01/29/2018] [Indexed: 11/29/2022] Open
Abstract
Coffee is a major tropical commodity crop that can provide supplementary habitat for native wildlife. In Asia, coffee production is an increasingly important driver of landscape transformation and shifts between different coffee species is a major dimension of agroforestry trends. Yet few studies have compared the ecological impacts of conversion between different coffee species. We evaluated whether or not the two species of coffee grown globally-Coffea arabica and C. canephora (denoted "robusta")-had equivalent avian conservation value in the Western Ghats, India, where robusta production has become increasingly dominant. We found that habitat specialist and functional guild diversity was higher in arabica, and that arabica was more profitable. However, robusta farms generally supported the same or slightly higher abundances of habitat specialists and functional guilds, largely due to dense canopy and landscape-level forest cover. Farming practices, chiefly pesticide use, may affect the suitability of coffee agroforests as habitat for avian specialists, and at present, robusta farmers tended to use less pesticide. Given future projections for arabica to robusta conversion in tropical Asia, our study indicates that certification efforts should prioritize maintaining native canopy shade trees and forest cover to ensure that coffee landscapes can continue providing biodiversity benefits.
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Affiliation(s)
- Charlotte H Chang
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, 08544, USA
| | - Krithi K Karanth
- Wildlife Conservation Society, 2300 Bronx Blvd, New York, USA.
- Centre for Wildlife Studies, 551, 7th Main Road Rajiv Gandhi Nagar, 2nd Phase, Kodigehalli, Bengaluru, 560097, India.
- Duke University, Durham, North Carolina, USA.
| | - Paul Robbins
- Nelson Institute, University of Wisconsin-Madison, Madison, Wisconsin, USA
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26
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Kormann UG, Hadley AS, Tscharntke T, Betts MG, Robinson WD, Scherber C. Primary rainforest amount at the landscape scale mitigates bird biodiversity loss and biotic homogenization. J Appl Ecol 2018. [DOI: 10.1111/1365-2664.13084] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Urs G. Kormann
- Agroecology Georg‐August University Göttingen Göttingen Germany
- Forest Biodiversity Research Network Department of Forest Ecosystems and Society Oregon State University Corvallis OR USA
| | - Adam S. Hadley
- Forest Biodiversity Research Network Department of Forest Ecosystems and Society Oregon State University Corvallis OR USA
| | - Teja Tscharntke
- Agroecology Georg‐August University Göttingen Göttingen Germany
| | - Matthew G. Betts
- Forest Biodiversity Research Network Department of Forest Ecosystems and Society Oregon State University Corvallis OR USA
| | - W. Douglas Robinson
- Oak Creek Lab of Biology Department of Fisheries and Wildlife Oregon State University Corvallis OR USA
| | - Christoph Scherber
- Agroecology Georg‐August University Göttingen Göttingen Germany
- Institute of Landscape Ecology Münster Germany
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27
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Emer C, Galetti M, Pizo MA, Guimarães PR, Moraes S, Piratelli A, Jordano P. Seed-dispersal interactions in fragmented landscapes - a metanetwork approach. Ecol Lett 2018; 21:484-493. [PMID: 29368364 DOI: 10.1111/ele.12909] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 11/25/2017] [Accepted: 12/12/2017] [Indexed: 01/11/2023]
Abstract
Mutualistic interactions repeatedly preserved across fragmented landscapes can scale-up to form a spatial metanetwork describing the distribution of interactions across patches. We explored the structure of a bird seed-dispersal (BSD) metanetwork in 16 Neotropical forest fragments to test whether a distinct subset of BSD-interactions may mediate landscape functional connectivity. The metanetwork is interaction-rich, modular and poorly connected, showing high beta-diversity and turnover of species and interactions. Interactions involving large-sized species were lost in fragments < 10 000 ha, indicating a strong filtering by habitat fragmentation on the functional diversity of BSD-interactions. Persistent interactions were performed by small-seeded, fast growing plant species and by generalist, small-bodied bird species able to cross the fragmented landscape. This reduced subset of interactions forms the metanetwork components persisting to defaunation and fragmentation, and may generate long-term deficits of carbon storage while delaying forest regeneration at the landscape level.
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Affiliation(s)
- Carine Emer
- Departmento de Ecologia, Instituto de Biociências, Universidade Estadual Paulista, CP 199, 13506-900, Rio Claro - SP, Brazil.,Integrative Ecology Group, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (EBD-CSIC), Av. Américo Vespucio 26, E-41092, Sevilla, Spain
| | - Mauro Galetti
- Departmento de Ecologia, Instituto de Biociências, Universidade Estadual Paulista, CP 199, 13506-900, Rio Claro - SP, Brazil
| | - Marco A Pizo
- Departmento de Zoologia, Instituto de Biociências, Universidade Estadual Paulista, CP 199, 13506-900, Rio Claro - SP, Brazil
| | - Paulo R Guimarães
- Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, 05508-090, São Paulo - SP, Brazil
| | - Suelen Moraes
- Departamento de Ciências Ambientais, Universidade Federal de São Carlos, Rodovia João Leme dos Santos, Km 110, SP-264, 18052-780, Sorocaba - SP, Brazil
| | - Augusto Piratelli
- Departamento de Ciências Ambientais, Universidade Federal de São Carlos, Rodovia João Leme dos Santos, Km 110, SP-264, 18052-780, Sorocaba - SP, Brazil
| | - Pedro Jordano
- Integrative Ecology Group, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (EBD-CSIC), Av. Américo Vespucio 26, E-41092, Sevilla, Spain
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28
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Deikumah JP, Kwafo R, Konadu VA. Land use types influenced avian assemblage structure in a forest-agriculture landscape in Ghana. Ecol Evol 2017; 7:8685-8697. [PMID: 29152169 PMCID: PMC5677502 DOI: 10.1002/ece3.3355] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 06/13/2017] [Accepted: 07/23/2017] [Indexed: 11/13/2022] Open
Abstract
The conservation of biodiversity within tropical forest regions does not lie only in the maintenance of natural forest areas, but on conservation strategies directed toward agricultural land types within which they are embedded. This study investigated variations in bird assemblages of different functional groups of forest-dependent birds in three agricultural land types, relative to distance from the interior of 34 tropical forest patches of varying sizes. Point counts were used to sample birds at each study site visited. Data from counts were used to estimate species richness, species evenness, and Simpson's diversity of birds. Mean species richness, evenness, and diversity were modeled as responses and as a function of agricultural land type, distance from the forest interior and three site-scale vegetation covariates (density of large trees, fruiting trees, and patch size) using generalized linear mixed-effect models. Mean observed species richness of birds varied significantly within habitat types. Mean observed species richness was highest in forest interior sites while sites located in farm centers recorded the lowest mean species richness. Species richness of forest specialists was strongly influenced by the type of agricultural land use. Fallow lands, density of large trees, and patch size strongly positively influenced forest specialists. Insectivorous and frugivorous birds were more species-rich in fallow lands while monoculture plantations favored nectarivorous birds. Our results suggest that poor agricultural practices can lead to population declines of forest-dependent birds particularly specialist species. Conservation actions should include proper land use management that ensures heterogeneity through retention of native tree species on farms in tropical forest-agriculture landscapes.
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Affiliation(s)
- Justus Precious Deikumah
- Department of Conservation Biology and EntomologySchool of Biological Sciences, University of Cape CoastCape CoastGhana
| | - Richard Kwafo
- Department of Conservation Biology and EntomologySchool of Biological Sciences, University of Cape CoastCape CoastGhana
| | - Vida Asieduwaa Konadu
- Department of Conservation Biology and EntomologySchool of Biological Sciences, University of Cape CoastCape CoastGhana
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29
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Latta SC, Brouwer NL, Olivieri A, Girard-Woolley J, Richardson JF. Long-term monitoring reveals an avian species credit in secondary forest patches of Costa Rica. PeerJ 2017; 5:e3539. [PMID: 28674671 PMCID: PMC5494173 DOI: 10.7717/peerj.3539] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 06/13/2017] [Indexed: 11/20/2022] Open
Abstract
Degraded and secondary forests comprise approximately 50% of remaining tropical forest. Bird community characteristics and population trends in secondary forests are infrequently studied, but secondary forest may serve as a “safety net” for tropical biodiversity. Less understood is the occurrence of time-delayed, community-level dynamics such as an extinction debt of specialist species or a species credit resulting from the recolonization of forest patches by extirpated species. We sought to elucidate patterns and magnitudes of temporal change in avian communities in secondary forest patches in Southern Costa Rica biannually over a 10 year period during the late breeding season and mid-winter. We classified birds caught in mist nets or recorded in point counts by residency status, and further grouped them based on preferred habitat, sensitivity to disturbance, conservation priority, foraging guild, and foraging strata. Using hierarchical, mixed-effects models we tested for trends among species that share traits. We found that permanent-resident species increased over time relative to migrants. In both seasons, primary forest species generally increased while species typical of secondary forest, scrub, or edge declined. Species relatively sensitive to habitat disturbance increased significantly over time, whereas birds less sensitive to disturbance decreased. Similarly, generalists with higher habitat breadth scores declined. Because, we found very few changes in vegetation characteristics in secondary forest patches, shifts in the avian community toward primary forest species represent a species credit and are likely related to vegetation changes in the broader landscape. We suggest that natural regeneration and maturation of secondary forests should be recognized as a positive conservation development of potential benefit even to species typical of primary forest.
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30
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Blendinger PG. Functional Equivalence in Seed Dispersal Effectiveness of Podocarpus parlatorei in Andean Fruit-Eating Bird Assemblages. Front Ecol Evol 2017. [DOI: 10.3389/fevo.2017.00057] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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31
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González-Varo JP, Carvalho CS, Arroyo JM, Jordano P. Unravelling seed dispersal through fragmented landscapes: Frugivore species operate unevenly as mobile links. Mol Ecol 2017; 26:4309-4321. [PMID: 28503829 DOI: 10.1111/mec.14181] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 04/19/2017] [Accepted: 05/05/2017] [Indexed: 11/27/2022]
Abstract
Seed dispersal constitutes a pivotal process in an increasingly fragmented world, promoting population connectivity, colonization and range shifts in plants. Unveiling how multiple frugivore species disperse seeds through fragmented landscapes, operating as mobile links, has remained elusive owing to methodological constraints for monitoring seed dispersal events. We combine for the first time DNA barcoding and DNA microsatellites to identify, respectively, the frugivore species and the source trees of animal-dispersed seeds in forest and matrix of a fragmented landscape. We found a high functional complementarity among frugivores in terms of seed deposition at different habitats (forest vs. matrix), perches (isolated trees vs. electricity pylons) and matrix sectors (close vs. far from the forest edge), cross-habitat seed fluxes, dispersal distances and canopy-cover dependency. Seed rain at the landscape-scale, from forest to distant matrix sectors, was characterized by turnovers in the contribution of frugivores and source-tree habitats: open-habitat frugivores replaced forest-dependent frugivores, whereas matrix trees replaced forest trees. As a result of such turnovers, the magnitude of seed rain was evenly distributed between habitats and landscape sectors. We thus uncover key mechanisms behind "biodiversity-ecosystem function" relationships, in this case, the relationship between frugivore diversity and landscape-scale seed dispersal. Our results reveal the importance of open-habitat frugivores, isolated fruiting trees and anthropogenic perching sites (infrastructures) in generating seed dispersal events far from the remnant forest, highlighting their potential to drive regeneration dynamics through the matrix. This study helps to broaden the "mobile-link" concept in seed dispersal studies by providing a comprehensive and integrative view of the way in which multiple frugivore species disseminate seeds through real-world landscapes.
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Affiliation(s)
- Juan P González-Varo
- Integrative Ecology Group, Estación Biológica de Doñana, EBD-CSIC, Sevilla, Spain.,Department of Zoology, Conservation Science Group, University of Cambridge, Cambridge, UK
| | - Carolina S Carvalho
- Departamento de Ecologia, Universidade Estadual Paulista (UNESP), Rio Claro, Brazil
| | - Juan M Arroyo
- Integrative Ecology Group, Estación Biológica de Doñana, EBD-CSIC, Sevilla, Spain
| | - Pedro Jordano
- Integrative Ecology Group, Estación Biológica de Doñana, EBD-CSIC, Sevilla, Spain
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32
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Elsen PR, Kalyanaraman R, Ramesh K, Wilcove DS. The importance of agricultural lands for Himalayan birds in winter. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2017; 31:416-426. [PMID: 27558794 DOI: 10.1111/cobi.12812] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 08/05/2016] [Accepted: 08/14/2016] [Indexed: 06/06/2023]
Abstract
The impacts of land-use change on biodiversity in the Himalayas are poorly known, notwithstanding widespread deforestation and agricultural intensification in this highly biodiverse region. Although intact primary forests harbor many Himalayan birds during breeding, a large number of bird species use agricultural lands during winter. We assessed how Himalayan bird species richness, abundance, and composition during winter are affected by forest loss stemming from agriculture and grazing. Bird surveys along 12 elevational transects within primary forest, low-intensity agriculture, mixed subsistence agriculture, and intensively grazed pastures in winter revealed that bird species richness and abundance were greatest in low-intensity and mixed agriculture, intermediate in grazed pastures, and lowest in primary forest at both local and landscape scales; over twice as many species and individuals were recorded in low-intensity agriculture than in primary forest. Bird communities in primary forests were distinct from those in all other land-use classes, but only 4 species were unique to primary forests. Low-, medium-, and high-intensity agriculture harbored 32 unique species. Of the species observed in primary forest, 80% had equal or greater abundance in low-intensity agricultural lands, underscoring the value of these lands in retaining diverse community assemblages at high densities in winter. Among disturbed landscapes, bird species richness and abundance declined as land-use intensity increased, especially in high-intensity pastures. Our results suggest that agricultural landscapes are important for most Himalayan bird species in winter. But agricultural intensification-especially increased grazing-will likely result in biodiversity losses. Given that forest reserves alone may inadequately conserve Himalayan birds in winter, comprehensive conservation strategies in the region must go beyond protecting intact primary forests and ensure that low-intensity agricultural lands are not extensively converted to high-intensity pastures.
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Affiliation(s)
- Paul R Elsen
- Woodrow Wilson School, Princeton University, Princeton, NJ, 08544, U.S.A
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, U.S.A
| | | | | | - David S Wilcove
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, U.S.A
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Kennedy CM, Zipkin EF, Marra PP. Differential matrix use by Neotropical birds based on species traits and landscape condition. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2017; 27:619-631. [PMID: 27859995 DOI: 10.1002/eap.1470] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 10/17/2016] [Accepted: 10/21/2016] [Indexed: 06/06/2023]
Abstract
There is considerable uncertainty about the role of human-modified habitats in supporting species in fragmented landscapes. This is because few studies sample outside of native habitats in the "matrix." Those that do, often fail to sample landscapes in a way that accounts for the confounding effects of native habitat pattern and species detection biases that can obscure species responses. We employed multi-species hierarchical occupancy models to determine the use of human-modified habitats by Neotropical birds in landscapes that were similar in forest amount and configuration but surrounded by a matrix of agriculture (predominately pasture), bauxite mining (surface mining for aluminum), or suburban development in central Jamaica. We found that the vast majority of bird species used the matrix: with the highest mean occurrences for open-associated, followed by generalist, and last forest-associated species. Migrant species had higher mean occurrences in all matrix types relative to resident species. Contrary to our expectation, mean occurrence for the entire species community, and for forest-associated and migrant species, were highest in bauxite, intermediate in suburban, and lowest in agriculture. Open-associated species had higher occurrences in both bauxite and agricultural matrices, whereas generalist species had higher occurrences in suburban matrices. Additional behavioral observations indicated that Neotropical birds used matrix areas, particularly scattered trees, to acquire food, and secondarily, as movement conduits. Matrix use patterns reflected the differential availability of potential resources and structural connectivity across the three landscape types, but only for those species adapted to open/edge environments and with generalized habitat requirements. Patterns of matrix use by forest specialists reflected the differential levels of degradation of the native forest; thus, we propose that higher matrix use for forest-dependent species may be induced by diminished within-forest resources. These results underscore that effective management of human-modified matrices requires in-depth understanding of the trade-offs between the benefits available in the matrix and the impacts on the disturbance of native habitats.
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Affiliation(s)
- Christina M Kennedy
- The Nature Conservancy, Global Conservation Lands Program, 117 East Mountain Avenue, Fort Collins, Colorado, 80524, USA
| | - Elise F Zipkin
- Department of Integrative Biology and Ecology, Evolutionary Biology, and Behavior Program, East Lansing, Michigan, 48824, USA
| | - Peter P Marra
- Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, 3001 Connecticut Avenue, Washington, D.C., 20008, USA
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Hiley JR, Bradbury RB, Thomas CD. Impacts of habitat change and protected areas on alpha and beta diversity of Mexican birds. DIVERS DISTRIB 2016. [DOI: 10.1111/ddi.12483] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Jonathan R. Hiley
- Department of Biology; University of York; York Yorkshire YO10 5DD UK
| | - Richard B. Bradbury
- RSPB Centre for Conservation Science; Royal Society for the Protection of Birds, The Lodge; Sandy Bedfordshire SG19 2DL UK
- RSPB Centre for Conservation Science; The David Attenborough Building Pembroke Street Cambridge CB2 3QZ UK
- Conservation Science Group; Department of Zoology; University of Cambridge; Downing Street Cambridge CB2 3EJ UK
| | - Chris D. Thomas
- Department of Biology; University of York; York Yorkshire YO10 5DD UK
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Da Silveira NS, Niebuhr BBS, Muylaert RDL, Ribeiro MC, Pizo MA. Effects of Land Cover on the Movement of Frugivorous Birds in a Heterogeneous Landscape. PLoS One 2016; 11:e0156688. [PMID: 27257810 PMCID: PMC4892584 DOI: 10.1371/journal.pone.0156688] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 05/18/2016] [Indexed: 11/30/2022] Open
Abstract
Movement is a key spatiotemporal process that enables interactions between animals and other elements of nature. The understanding of animal trajectories and the mechanisms that influence them at the landscape level can yield insight into ecological processes and potential solutions to specific ecological problems. Based upon optimal foraging models and empirical evidence, we hypothesized that movement by thrushes is highly tortuous (low average movement speeds and homogeneous distribution of turning angles) inside forests, moderately tortuous in urban areas, which present intermediary levels of resources, and minimally tortuous (high movement speeds and turning angles next to 0 radians) in open matrix types (e.g., crops and pasture). We used data on the trajectories of two common thrush species (Turdus rufiventris and Turdus leucomelas) collected by radio telemetry in a fragmented region in Brazil. Using a maximum likelihood model selection approach we fit four probability distribution models to average speed data, considering short-tailed, long-tailed, and scale-free distributions (to represent different regimes of movement variation), and one distribution to relative angle data. Models included land cover type and distance from forest-matrix edges as explanatory variables. Speed was greater farther away from forest edges and increased faster inside forest habitat compared to urban and open matrices. However, turning angle was not influenced by land cover. Thrushes presented a very tortuous trajectory, with many displacements followed by turns near 180 degrees. Thrush trajectories resembled habitat and edge dependent, tortuous random walks, with a well-defined movement scale inside each land cover type. Although thrushes are habitat generalists, they showed a greater preference for forest edges, and thus may be considered edge specialists. Our results reinforce the importance of studying animal movement patterns in order to understand ecological processes such as seed dispersal in fragmented areas, where the percentage of remaining habitat is dwindling.
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Affiliation(s)
- Natalia Stefanini Da Silveira
- Departament of Ecology, Spatial Ecology and Conservation Lab, Universidade Estadual Paulista Julio de Mesquita Filho, Rio Claro, São Paulo, Brazil
- * E-mail:
| | - Bernardo Brandão S. Niebuhr
- Departament of Ecology, Spatial Ecology and Conservation Lab, Universidade Estadual Paulista Julio de Mesquita Filho, Rio Claro, São Paulo, Brazil
| | - Renata de Lara Muylaert
- Departament of Ecology, Spatial Ecology and Conservation Lab, Universidade Estadual Paulista Julio de Mesquita Filho, Rio Claro, São Paulo, Brazil
| | - Milton Cezar Ribeiro
- Departament of Ecology, Spatial Ecology and Conservation Lab, Universidade Estadual Paulista Julio de Mesquita Filho, Rio Claro, São Paulo, Brazil
| | - Marco Aurélio Pizo
- Departament of Zoology, Universidade Estadual Paulista Julio de Mesquita Filho, Rio Claro, São Paulo, Brazil
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Modeling the effect of habitat selection mechanisms on population responses to landscape structure. Ecol Modell 2016. [DOI: 10.1016/j.ecolmodel.2016.03.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Cáceres A, Melo M, Barlow J, Mills MSL. Radiotelemetry reveals key data for the conservation of Sheppardia gabela
(Rand, 1957) in the Angolan Escarpment forest. Afr J Ecol 2016. [DOI: 10.1111/aje.12283] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Aimy Cáceres
- CIBIO-InBIO-Centro de Investigação em Biodiversidade e Recursos Genéticos; Universidade do Porto; Campus Agrário de Vairão Rua Padre Armando Quintas 4485-661 Vairão Portugal
- ISCED-Instituto Superior de Ciências da Educação da Huíla; Rua Sarmento Rodrigues s/n CP 230 Lubango Angola
| | - Martim Melo
- CIBIO-InBIO-Centro de Investigação em Biodiversidade e Recursos Genéticos; Universidade do Porto; Campus Agrário de Vairão Rua Padre Armando Quintas 4485-661 Vairão Portugal
- ISCED-Instituto Superior de Ciências da Educação da Huíla; Rua Sarmento Rodrigues s/n CP 230 Lubango Angola
- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute; University of Cape Town; Rondebosch 7701 Cape Town South Africa
| | - Jos Barlow
- Lancaster Environment Centre; Lancaster University; Lancaster LA1 4YQ U.K
| | - Michael S. L. Mills
- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute; University of Cape Town; Rondebosch 7701 Cape Town South Africa
- A. P. Leventis Ornithological Research Institute; University of Jos; PO Box 13404 Jos Plateau State Nigeria
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Zahawi RA, Duran G, Kormann U. Sixty-Seven Years of Land-Use Change in Southern Costa Rica. PLoS One 2015; 10:e0143554. [PMID: 26599325 PMCID: PMC4657907 DOI: 10.1371/journal.pone.0143554] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 11/05/2015] [Indexed: 11/19/2022] Open
Abstract
Habitat loss and fragmentation of forests are among the biggest threats to biodiversity and associated ecosystem services in tropical landscapes. We use the vicinity of the Las Cruces Biological Station in southern Costa Rica as a regional case study to document seven decades of land-use change in one of the most intensively studied sites in the Neotropics. Though the premontane wet forest was largely intact in 1947, a wave of immigration in 1952 initiated rapid changes over a short period. Overall forest cover was reduced during each time interval analyzed (1947-1960, 1960-1980, 1980-1997, 1997-2014), although the vast majority of forest loss (>90%) occurred during the first two time intervals (1947-1960, 1960-1980) with an annual deforestation rate of 2.14% and 3.86%, respectively. The rate dropped to <2% thereafter and has been offset by forest recovery in fallow areas more recently, but overall forest cover has continued to decline. Approximately 27.9% of the study area is forested currently. Concomitantly, the region shifted from a single contiguous forest to a series of progressively smaller forest fragments with each successive survey. A strong reduction in the amount of core habitat was paralleled by an increased proportion of edge habitat, due to the irregular shape of many forest fragments. Structural connectivity, however, remains high, with an expansive network of >100 km of linear strips of vegetation within a 3 km radius of the station, which may facilitate landscape-level movement for some species. Despite the extent of forest loss, a substantial number of regional landscape-level studies over the past two decades have demonstrated the persistence of many groups of organisms such as birds and mammals. Nonetheless, the continued decline in the quantity and quality of remaining habitat (~30% of remaining forest is secondary), as well as the threat of an extinction debt (or time lag in species loss), may result in the extirpation of additional species if more proactive conservation measures are not taken to reverse current trends-a pattern that reflects many other tropical regions the world over.
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Affiliation(s)
- Rakan A. Zahawi
- Las Cruces Biological Station, Organization for Tropical Studies, Apartado 73–8257, San Vito de Coto Brus, Costa Rica
- * E-mail:
| | - Guillermo Duran
- Centro de Recursos Hídricos para Centroamérica y el Caribe, Universidad Nacional de Costa Rica, Sede Chorotega, Liberia, Costa Rica
| | - Urs Kormann
- Department of Agroecology, University of Goettingen, Grisebachstr. 6, D-37077, Goettingen, Germany
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Edwards D, Gilroy J, Thomas G, Uribe C, Haugaasen T. Land-Sparing Agriculture Best Protects Avian Phylogenetic Diversity. Curr Biol 2015; 25:2384-91. [DOI: 10.1016/j.cub.2015.07.063] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 07/23/2015] [Accepted: 07/24/2015] [Indexed: 10/23/2022]
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40
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Maas B, Karp DS, Bumrungsri S, Darras K, Gonthier D, Huang JCC, Lindell CA, Maine JJ, Mestre L, Michel NL, Morrison EB, Perfecto I, Philpott SM, Şekercioğlu ÇH, Silva RM, Taylor PJ, Tscharntke T, Van Bael SA, Whelan CJ, Williams-Guillén K. Bird and bat predation services in tropical forests and agroforestry landscapes. Biol Rev Camb Philos Soc 2015. [PMID: 26202483 DOI: 10.1111/brv.12211] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Understanding distribution patterns and multitrophic interactions is critical for managing bat- and bird-mediated ecosystem services such as the suppression of pest and non-pest arthropods. Despite the ecological and economic importance of bats and birds in tropical forests, agroforestry systems, and agricultural systems mixed with natural forest, a systematic review of their impact is still missing. A growing number of bird and bat exclosure experiments has improved our knowledge allowing new conclusions regarding their roles in food webs and associated ecosystem services. Here, we review the distribution patterns of insectivorous birds and bats, their local and landscape drivers, and their effects on trophic cascades in tropical ecosystems. We report that for birds but not bats community composition and relative importance of functional groups changes conspicuously from forests to habitats including both agricultural areas and forests, here termed 'forest-agri' habitats, with reduced representation of insectivores in the latter. In contrast to previous theory regarding trophic cascade strength, we find that birds and bats reduce the density and biomass of arthropods in the tropics with effect sizes similar to those in temperate and boreal communities. The relative importance of birds versus bats in regulating pest abundances varies with season, geography and management. Birds and bats may even suppress tropical arthropod outbreaks, although positive effects on plant growth are not always reported. As both bats and birds are major agents of pest suppression, a better understanding of the local and landscape factors driving the variability of their impact is needed.
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Affiliation(s)
- Bea Maas
- Agroecology, Georg-August University, Grisebachstraße 6, 37077, Goettingen, Germany. .,Division of Tropical Ecology and Animal Biodiversity, Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030, Vienna, Austria.
| | - Daniel S Karp
- The Nature Conservancy, 201 Mission Street, 4th Floor, San Francisco, CA, 94105, U.S.A.,Department of Environmental Science, Policy, and Management, University of California, Mulford Hall, 130 Hilgard Way, Berkeley, CA, 94720, U.S.A
| | - Sara Bumrungsri
- Department of Biology, Faculty of Science, Prince of Songkla University, Thailand 15 Karnjanavanich Rd., Hat Yai, Songkhla, 90110, Thailand
| | - Kevin Darras
- Agroecology, Georg-August University, Grisebachstraße 6, 37077, Goettingen, Germany
| | - David Gonthier
- The Nature Conservancy, 201 Mission Street, 4th Floor, San Francisco, CA, 94105, U.S.A.,School of Natural Resources and Environment, University of Michigan, 440 Church Street, Ann Arbor, MI, 48109, U.S.A
| | - Joe C-C Huang
- Department of Biological Sciences, Texas Tech University, Box 43131, Lubbock, TX, 79409, U.S.A.,Southeast Asian Bat Conservation and Research Unit, Department of Biological Science, Box 43131, Texas Tech University, Lubbock, TX, 79409-3131, U.S.A
| | - Catherine A Lindell
- Integrative Biology Department, Center for Global Change and Earth Observations, Michigan State University, 288 Farm Lane RM 203, East Lansing, MI, 48824, U.S.A
| | - Josiah J Maine
- Cooperative Wildlife Research Laboratory, Department of Zoology, Center for Ecology, Southern Illinois University, 1125 Lincoln Dr., Carbondale, IL, 62901, U.S.A
| | - Laia Mestre
- CREAF, Carretera de Bellaterra a l'Autònoma, s/n, 08193, Cerdanyola del Vallès,, Barcelona, Spain.,Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia, Universitat Autònoma, Carretera de Bellaterra a l'Autònoma, s/n, 08193 Cerdanyola del Vallès, Barcelona, Spain.,Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, 750 07, Uppsala, Sweden
| | - Nicole L Michel
- School of Environment and Sustainability, University of Saskatchewan, 117 Science Place, Saskatoon, Saskatchewan, S7N 5C8, Canada
| | - Emily B Morrison
- Integrative Biology Department, Center for Global Change and Earth Observations, Michigan State University, 288 Farm Lane RM 203, East Lansing, MI, 48824, U.S.A
| | - Ivette Perfecto
- School of Natural Resources and Environment, University of Michigan, 440 Church Street, Ann Arbor, MI, 48109, U.S.A
| | - Stacy M Philpott
- Environmental Studies Department, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA, 95062, U.S.A
| | - Çagan H Şekercioğlu
- Department of Biology, University of Utah, 257 South 1400 East, Rm. 201, Salt Lake City, UT, 84112, U.S.A.,College of Sciences, Koç University, Rumelifeneri, Sariyer, 34450, Istanbul, Turkey
| | - Roberta M Silva
- Programa de Pós-Graduação em Ecologia e Conservação da Biodiversidade, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, 45662-900, Bahia, Brazil
| | - Peter J Taylor
- School of Life Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa.,SARChI Chair on Biodiversity Value & Change and Centre for Invasion Biology, School of Mathematical & Natural Sciences, University of Venda, P. Bag X5050, Thohoyandou, 0950, South Africa
| | - Teja Tscharntke
- Agroecology, Georg-August University, Grisebachstraße 6, 37077, Goettingen, Germany
| | - Sunshine A Van Bael
- Department of Ecology and Evolutionary Biology, Tulane University, 6823 St. Charles Avenue, New Orleans, LA, 70118, U.S.A.,Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Balboa, Ancon, Republic of Panama
| | - Christopher J Whelan
- Illinois Natural History Survey, c/o Biological Sciences, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, U.S.A
| | - Kimberly Williams-Guillén
- School of Natural Resources and Environment, University of Michigan, 440 Church Street, Ann Arbor, MI, 48109, U.S.A.,Paso Pacífico, PO Box 1244, Ventura, CA, 94302, U.S.A
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Gilroy JJ, Medina Uribe CA, Haugaasen T, Edwards DP. Effect of scale on trait predictors of species responses to agriculture. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2015; 29:463-472. [PMID: 25395246 DOI: 10.1111/cobi.12422] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 08/11/2014] [Indexed: 06/04/2023]
Abstract
Species persistence in human-altered landscapes can depend on factors operating at multiple spatial scales. To understand anthropogenic impacts on biodiversity, it is useful to examine relationships between species traits and their responses to land-use change. A key knowledge gap concerns whether these relationships vary depending on the scale of response under consideration. We examined how local- and large-scale habitat variables influence the occupancy dynamics of a bird community in cloud forest zones in the Colombian Chocó-Andes. Using data collected across a continuum of forest and agriculture, we examined which traits best predict species responses to local variation in farmland and which traits best predict species responses to isolation from contiguous forest. Global range size was a strong predictor of species responses to agriculture at both scales; widespread species were less likely to decline as local habitat cover decreased and as distance from forest increased. Habitat specialization was a strong predictor of species responses only at the local scale. Open-habitat species were particularly likely to increase as pasture increased, but they were relatively insensitive to variation in distance to forest. Foraging plasticity and flocking behavior were strong predictors of species responses to distance from forest, but not their responses to local habitat. Species with lower plasticity in foraging behaviors and obligate flock-following species were more likely to decline as distance from contiguous forest increased. For species exhibiting these latter traits, persistence in tropical landscapes may depend on the protection of larger contiguous blocks of forest, rather than the integration of smaller-scale woodland areas within farmland. Species listed as threatened or near threatened on the International Union for Conservation of Nature Red List were also more likely to decline in response to both local habitat quality and isolation from forest relative to least-concern species, underlining the importance of contiguous forests for threatened taxa.
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Affiliation(s)
- James J Gilroy
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
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Gilroy JJ, Edwards FA, Medina Uribe CA, Haugaasen T, Edwards DP. EDITOR'S CHOICE: Surrounding habitats mediate the trade-off between land-sharing and land-sparing agriculture in the tropics. J Appl Ecol 2014. [DOI: 10.1111/1365-2664.12284] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- James J. Gilroy
- Department of Ecology and Natural Resource Management; Norwegian University of Life Sciences; 1430 Ås Norway
| | | | - Claudia A. Medina Uribe
- Instituto de Investigación de Recursos Biológicos Alexander von Humboldt; Calle 28A # 15-09 Bogotá Colombia
| | - Torbjørn Haugaasen
- Department of Ecology and Natural Resource Management; Norwegian University of Life Sciences; 1430 Ås Norway
| | - David P. Edwards
- Department of Animal and Plant Sciences; University of Sheffield; Sheffield S10 2TN UK
- School of Marine & Tropical Biology; James Cook University; Cairns Queensland 4811 Australia
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43
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Berens DG, Chama L, Albrecht J, Farwig N. High Conservation Value of Forest Fragments for Plant and Frugivore Communities in a Fragmented Forest Landscape in South Africa. Biotropica 2014. [DOI: 10.1111/btp.12104] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Dana G. Berens
- Department of Ecology - Conservation Ecology; Fachbereich Biologie; Philipps-Universität Marburg; Karl-von-Frisch Str. 8 DE-35043 Marburg Germany
| | - Lackson Chama
- Department of Ecology - Conservation Ecology; Fachbereich Biologie; Philipps-Universität Marburg; Karl-von-Frisch Str. 8 DE-35043 Marburg Germany
| | - Jörg Albrecht
- Department of Ecology - Conservation Ecology; Fachbereich Biologie; Philipps-Universität Marburg; Karl-von-Frisch Str. 8 DE-35043 Marburg Germany
| | - Nina Farwig
- Department of Ecology - Conservation Ecology; Fachbereich Biologie; Philipps-Universität Marburg; Karl-von-Frisch Str. 8 DE-35043 Marburg Germany
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44
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Cox WA, Thompson FR, Cox AS, Faaborg J. Post-fledging survival in passerine birds and the value of post-fledging studies to conservation. J Wildl Manage 2014. [DOI: 10.1002/jwmg.670] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- W. Andrew Cox
- Department of Fisheries and Wildlife Sciences; University of Missouri; 302 ABNR Columbia MO 65211 USA
| | - Frank R. Thompson
- USDA Forest Service Northern Research Station; University of Missouri; 202 ABNR Columbia MO 65211 USA
| | - Allison S. Cox
- Independent Researcher; 5537 N. Autumn Drive Columbia MO 65202 USA
| | - John Faaborg
- Division of Biological Sciences; University of Missouri; 105 Tucker Hall Columbia MO 65211 USA
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Sandor ME, Chazdon RL. Remnant trees affect species composition but not structure of tropical second-growth forest. PLoS One 2014; 9:e83284. [PMID: 24454700 PMCID: PMC3890367 DOI: 10.1371/journal.pone.0083284] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 11/12/2013] [Indexed: 11/18/2022] Open
Abstract
Remnant trees, spared from cutting when tropical forests are cleared for agriculture or grazing, act as nuclei of forest regeneration following field abandonment. Previous studies on remnant trees were primarily conducted in active pasture or old fields abandoned in the previous 2-3 years, and focused on structure and species richness of regenerating forest, but not species composition. Our study is among the first to investigate the effects of remnant trees on neighborhood forest structure, biodiversity, and species composition 20 years post-abandonment. We compared the woody vegetation around individual remnant trees to nearby plots without remnant trees in the same second-growth forests ("control plots"). Forest structure beneath remnant trees did not differ significantly from control plots. Species richness and species diversity were significantly higher around remnant trees. The species composition around remnant trees differed significantly from control plots and more closely resembled the species composition of nearby old-growth forest. The proportion of old-growth specialists and generalists around remnant trees was significantly greater than in control plots. Although previous studies show that remnant trees may initially accelerate secondary forest growth, we found no evidence that they locally affect stem density, basal area, and seedling density at later stages of regrowth. Remnant trees do, however, have a clear effect on the species diversity, composition, and ecological groups of the surrounding woody vegetation, even after 20 years of forest regeneration. To accelerate the return of diversity and old-growth forest species into regrowing forest on abandoned land, landowners should be encouraged to retain remnant trees in agricultural or pastoral fields.
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Affiliation(s)
- Manette E. Sandor
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Robin L. Chazdon
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, United States of America
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Vilchez Mendoza S, Harvey CA, Sáenz JC, Casanoves F, Pablo Carvajal J, González Villalobos J, Hernandez B, Medina A, Montero J, Sánchez Merlo D, Sinclair FL. Consistency in bird use of tree cover across tropical agricultural landscapes. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2014; 24:158-168. [PMID: 24640541 DOI: 10.1890/13-0585.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In tropical regions where forests have been replaced by agriculture, the future of biodiversity is increasingly dependent on the presence of remnant forest patches and on-farm tree cover within agricultural landscapes. While there is growing evidence of the importance of tree cover within agricultural landscapes, most studies have been conducted in a single landscape, making it difficult to ascertain whether the conservation value of different types of tree cover can be generalized across landscapes. To explore whether use of different forms of tree cover by birds is consistent across landscapes, we compared the number of individuals, species richness, and diversity of birds associated with different forms of tree cover in four agricultural landscapes in Central America, using a standardized methodology and sampling effort. In each landscape, we compared bird assemblages in six tree cover types (secondary forests, riparian forests, forest fallows, live fences, pastures with high tree cover, and pastures with low tree cover). We observed a total of 10 723 birds of 283 species, with 83-196 species per landscape. The specific patterns of bird species richness, number of individuals, and diversity associated with tree cover types varied across the four landscapes, but these variables were consistently higher in the forest forms of tree cover (riparian forests, secondary forests, and forest fallows) than in non-forest habitats. In addition, forest forms of tree cover had distinct species composition from non-forest forms in all landscapes. There was also consistency in the use of different types of tree cover by forest birds across the four landscapes, with higher richness and number of individuals of forest birds in forested than non-forested forms of tree cover, and more forest bird species in pastures with high tree cover than in pastures with low tree cover. Our findings indicate that riparian and secondary forests are consistently of higher value for bird conservation (particularly for forest species) than live fences and pastures with tree cover. Consequently, agricultural and land use policies that promote the retention of secondary and riparian forests and increase tree cover within pastures would greatly benefit bird conservation, regardless of the landscape in which they are applied.
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The use of pasture trees by birds in a tropical montane landscape in Monteverde, Costa Rica. JOURNAL OF TROPICAL ECOLOGY 2013. [DOI: 10.1017/s0266467413000503] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Abstract:Conversion of forests to agricultural land may require many bird species to use resources in fragmented landscapes in order to persist. Pasture trees can make agricultural landscapes more hospitable for birds, but we do not know what factors promote bird visitation to pasture trees. Bird use of 26 focal trees of a common pasture species, Sapium glandulosum (Euphorbiaceae), was examined in three pastures in a montane landscape in Costa Rica to understand factors influencing bird visitation. Bird visits were analysed in relation to pasture tree size, distance from forest edge, degree of isolation and epiphyte load. Foraging resources (epiphyte or tree substrate) were also measured. From May–July 2012, 52 bird species from 20 families were recorded from 926 unique visits. Bird visitation was best explained by tree size, degree of isolation and epiphyte load such that larger, more isolated trees with higher epiphyte loads attracted more birds. Birds preferred food resources from focal trees (51% of visits) rather than their epiphytes (5% of visits). The results corroborate previous findings that mature pasture trees, even when isolated, may contribute more to species persistence than smaller trees.
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Deikumah JP, McAlpine CA, Maron M. Matrix intensification alters avian functional group composition in adjacent rainforest fragments. PLoS One 2013; 8:e74852. [PMID: 24058634 PMCID: PMC3772896 DOI: 10.1371/journal.pone.0074852] [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: 05/23/2013] [Accepted: 08/06/2013] [Indexed: 11/18/2022] Open
Abstract
Conversion of farmland land-use matrices to surface mining is an increasing threat to the habitat quality of forest remnants and their constituent biota, with consequences for ecosystem functionality. We evaluated the effects of matrix type on bird community composition and the abundance and evenness within avian functional groups in south-west Ghana. We hypothesized that surface mining near remnants may result in a shift in functional composition of avifaunal communities, potentially disrupting ecological processes within tropical forest ecosystems. Matrix intensification and proximity to the remnant edge strongly influenced the abundance of members of several functional guilds. Obligate frugivores, strict terrestrial insectivores, lower and upper strata birds, and insect gleaners were most negatively affected by adjacent mining matrices, suggesting certain ecosystem processes such as seed dispersal may be disrupted by landscape change in this region. Evenness of these functional guilds was also lower in remnants adjacent to surface mining, regardless of the distance from remnant edge, with the exception of strict terrestrial insectivores. These shifts suggest matrix intensification can influence avian functional group composition and related ecosystem-level processes in adjacent forest remnants. The management of matrix habitat quality near and within mine concessions is important for improving efforts to preserveavian biodiversity in landscapes undergoing intensification such as through increased surface mining.
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Affiliation(s)
- Justus P. Deikumah
- Landscape Ecology and Conservation Group, School of Geography, Planning and Environmental Management, The University of Queensland, Brisbane, Queensland, Australia
- * E-mail:
| | - Clive A. McAlpine
- Landscape Ecology and Conservation Group, School of Geography, Planning and Environmental Management, The University of Queensland, Brisbane, Queensland, Australia
| | - Martine Maron
- Landscape Ecology and Conservation Group, School of Geography, Planning and Environmental Management, The University of Queensland, Brisbane, Queensland, Australia
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Chandler RB, King DI, Raudales R, Trubey R, Chandler C, Chávez VJA. A small-scale land-sparing approach to conserving biological diversity in tropical agricultural landscapes. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2013; 27:785-795. [PMID: 23551570 DOI: 10.1111/cobi.12046] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 11/12/2012] [Indexed: 06/02/2023]
Abstract
Two contrasting strategies have been proposed for conserving biological diversity while meeting the increasing demand for agricultural products: land sparing and land sharing production systems. Land sparing involves increasing yield to reduce the amount of land needed for agriculture, whereas land-sharing agricultural practices incorporate elements of native ecosystems into the production system itself. Although the conservation value of these systems has been extensively debated, empirical studies are lacking. We compared bird communities in shade coffee, a widely practiced land-sharing system in which shade trees are maintained within the coffee plantation, with bird communities in a novel, small-scale, land-sparing coffee-production system (integrated open canopy or IOC coffee) in which farmers obtain higher yields under little or no shade while conserving an area of forest equal to the area under cultivation. Species richness and diversity of forest-dependent birds were higher in the IOC coffee farms than in the shade coffee farms, and community composition was more similar between IOC coffee and primary forest than between shade coffee and primary forest. Our study represents the first empirical comparison of well-defined land sparing and land sharing production systems. Because IOC coffee farms can be established by allowing forest to regenerate on degraded land, widespread adoption of this system could lead to substantial increases in forest cover and carbon sequestration without compromising agricultural yield or threatening the livelihoods of traditional small farmers. However, we studied small farms (<5 ha); thus, our results may not generalize to large-scale land-sharing systems. Furthermore, rather than concluding that land sparing is generally superior to land sharing, we suggest that the optimal approach depends on the crop, local climate, and existing land-use patterns.
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Affiliation(s)
- Richard B Chandler
- Department of Environmental Conservation, University of Massachusetts, 160 Holdsworth Way, Amherst, MA 01003, USA.
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The value of remnant trees in pastures for a neotropical poison frog. JOURNAL OF TROPICAL ECOLOGY 2013. [DOI: 10.1017/s0266467413000382] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Abstract:Conversion of natural habitats to anthropogenic land uses is a primary cause of amphibian declines in species-rich tropical regions. However, agricultural lands are frequently used by a subset of forest-associated species, and the habitat value of a given land use is likely modified by the presence and characteristics of remnant trees. Here we used mark–recapture methods to examine abundances and movement probability of the poison frog, Oophaga pumilio, at individual trees in forest-fragment edges and adjacent pastures in north-eastern Costa Rica. One hundred and forty-seven trees were surveyed at three replicate sites that each included a forest fragment and adjacent pasture. Trees were sampled at distances of ≤30 m into forest and ≤150 m into pastures for Oophaga pumilio, and local environmental characteristics were measured at each tree. We also measured indices of physical condition (size and endurance) of frogs captured in forest edges and in nearby pastures. Analyses of 167 marked individuals showed no difference in per-tree abundances or sex ratios between pasture and forest edges. We found significant interactions between habitat type and leaf-litter cover, tree dbh and number of logs, indicating greater influence of local variables on abundances in pastures. Movement among trees was infrequent and not predicted by sex, size, habitat type or environmental variables. While results of endurance tests did not differ for individuals from the two habitats, frogs captured in pastures were, on average, larger than frogs captured in forest edges. These data indicate that remnant trees are important habitat features for O. pumilio in pastures and corroborate research in other systems that suggests that large relictual trees should be retained to maximize the potential for altered landscapes to provide habitat for native species.
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