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Antalffy JM, Rowley MG, Johnson SB, Cant-Woodside S, Freid EH, Omland KE, Fagan ME. Comparing global and local maps of the Caribbean pine forests of Andros, home of the critically endangered Bahama Oriole. Environ Monit Assess 2021; 193:817. [PMID: 34791534 DOI: 10.1007/s10661-021-09560-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 10/19/2021] [Indexed: 06/13/2023]
Abstract
Forest loss is occurring at alarming rates across the globe. The pine rockland forests of Andros, The Bahamas, likely represent some of the largest stands of Bahamian subspecies of Caribbean pine in the world. Given the unique species that inhabit these pine forests, such as the endemic and critically endangered Bahama Oriole, monitoring habitats on Andros is crucial to inform conservation planning. We developed a 2019 land classification map to assess the status of nine terrestrial habitats on Andros. Our Random Forest classification model predicted habitat classes with high overall accuracy. Caribbean pine was the dominant land class making up roughly one-third of the total terrestrial area. Whereas much of the pine forest area was found as small patches, most were close to other patches of pine suggesting isolation of forest patches is low. We compared our known intact forest areas to recent forest loss identified by the Hansen et al. Global Forest Change product and assessed areas of habitat disturbance in high-resolution imagery. Our results suggest that this global map overpredicted forest loss on Andros. The small degree of true forest loss on Andros was driven mostly by anthropogenic activity. A cross-tabulation of the Hansen forest loss with fire data showed that understory fires were frequently associated with falsely classified deforestation. Given the threats of climate change to this open forest type-intensifying fire regimes, strengthening hurricanes, and sea level rise-monitoring changes in open forest extent is a critical task across the Caribbean region and the world.
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Affiliation(s)
- Janine M Antalffy
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, USA
| | - Michael G Rowley
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, USA
| | | | | | | | - Kevin E Omland
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, USA
| | - Matthew E Fagan
- Department of Geography and Environmental Systems, University of Maryland, Baltimore County, Baltimore, USA
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Fagan ME. A lesson unlearned? Underestimating tree cover in drylands biases global restoration maps. Glob Chang Biol 2020; 26:4679-4690. [PMID: 32614489 DOI: 10.1111/gcb.15187] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/02/2020] [Indexed: 06/11/2023]
Abstract
Two recent global maps of tree restoration potential have identified vast regions where tree cover could be increased, ranging from 0.9 to 2.3 billion hectares. Both maps, however, emphasized dryland regions, with arid biomes making up 36%-42% of potential restoration area. Dryland biomes have repeatedly been recognized as inappropriate regions for expanding tree cover due to the risks of biodiversity loss, water overconsumption, and fire, so maps that highlight these regions for restoration must sustain careful scrutiny. Here, I show that both recent attempts to map restoration potential in arid regions have been hindered by underlying errors in the global tree cover maps they used. Systematic underestimates of existing sparse tree cover led directly to large overestimates of the potential for tree recovery in drylands. The Atlas of Forest Landscape Restoration Opportunities (Laestadius et al., Unasylva, 2011, 62, 47) overestimated tree restoration potential across a third of arid biomes by between 7% and 20% (55-166 million hectares [Mha]). Similarly, Bastin, Finegold, Garcia, Mollicone, et al. (Science, 2019, 365, 76) overestimated tree restoration potential across all arid biomes by 33%-45% (316-440 Mha). These inaccuracies limit the utility of this research for policy decisions in drylands and overstate the potential for tree planting to address climate change. Given this long-standing but underappreciated challenge in mapping global tree cover, I propose various ways forward that keep this lesson in mind. To better monitor and restore tree cover, I call for re-interpretation and correction of existing global maps, and for a new focus on quantifying sparse tree cover in drylands and other systems.
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Affiliation(s)
- M E Fagan
- Department of Geography and Environmental Systems, University of Maryland Baltimore County, Baltimore, MD, USA
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3
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Zahawi RA, Reid JL, Fagan ME. Potential impacts of COVID-19 on tropical forest recovery. Biotropica 2020; 52:803-807. [PMID: 33173235 PMCID: PMC7646646 DOI: 10.1111/btp.12851] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/28/2020] [Accepted: 08/09/2020] [Indexed: 11/29/2022]
Abstract
COVID-19 has impacted humanity and the global environment in myriad ways, and more changes are on the horizon. Here we consider the impact of COVID-19 on our collective ability to restore degraded habitats and facilitate forest recovery in the tropics.
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Affiliation(s)
| | - J. Leighton Reid
- School of Plant and Environmental SciencesVirginia TechBlacksburgVAUSA
| | - Matthew E. Fagan
- Department of Geography and Environmental SystemsUniversity of MarylandBaltimore CountyBaltimoreMDUSA
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Gergel SE, Powell B, Baudron F, Wood SLR, Rhemtulla JM, Kennedy G, Rasmussen LV, Ickowitz A, Fagan ME, Smithwick EAH, Ranieri J, Wood SA, Groot JCJ, Sunderland TCH. Conceptual Links between Landscape Diversity and Diet Diversity: A Roadmap for Transdisciplinary Research. Bioscience 2020; 70:563-575. [PMID: 32665737 PMCID: PMC7340543 DOI: 10.1093/biosci/biaa048] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Malnutrition linked to poor quality diets affects at least 2 billion people. Forests, as well as agricultural systems linked to trees, are key sources of dietary diversity in rural settings. In the present article, we develop conceptual links between diet diversity and forested landscape mosaics within the rural tropics. First, we summarize the state of knowledge regarding diets obtained from forests, trees, and agroforests. We then hypothesize how disturbed secondary forests, edge habitats, forest access, and landscape diversity can function in bolstering dietary diversity. Taken together, these ideas help us build a framework illuminating four pathways (direct, agroecological, energy, and market pathways) connecting forested landscapes to diet diversity. Finally, we offer recommendations to fill remaining knowledge gaps related to diet and forest cover monitoring. We argue that better evaluation of the role of land cover complexity will help avoid overly simplistic views of food security and, instead, uncover nutritional synergies with forest conservation and restoration.
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Affiliation(s)
- Sarah E Gergel
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, Canada
| | - Bronwen Powell
- Department of Geography and BP is also affiliated with the Departments of African Studies and Anthropology at Pennsylvania State University, University Park, Pennsylvania
| | - FrÉdÉric Baudron
- International Maize and Wheat Improvement Center CIMMYT-Southern Africa Regional Office, Harare, Zimbabwe
| | | | - Jeanine M Rhemtulla
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, Canada
| | | | - Laura V Rasmussen
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, Canada
| | - Amy Ickowitz
- Center for International Forestry Research, Bogor, Indonesia
| | - Matthew E Fagan
- Department of Geography and Environmental Systems, University of Maryland—Baltimore County, Baltimore, Maryland
| | - Erica A H Smithwick
- Department of Geography and BP is also affiliated with the Departments of African Studies and Anthropology at Pennsylvania State University, University Park, Pennsylvania
| | | | - Stephen A Wood
- Nature Conservancy, Arlington, Virginia, and with the School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut
| | - Jeroen C J Groot
- Department of Farming Systems Ecology, Wageningen University and Research, Wageningen, The Netherlands
| | - Terry C H Sunderland
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, Canada
- Center for International Forestry Research, Bogor, Indonesia
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Rasmussen LV, Fagan ME, Ickowitz A, Wood SL, Kennedy G, Powell B, Baudron F, Gergel S, Jung S, Smithwick EA, Sunderland T, Wood S, Rhemtulla JM. Forest pattern, not just amount, influences dietary quality in five African countries. Global Food Security 2020. [DOI: 10.1016/j.gfs.2019.100331] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Affiliation(s)
- Matthew E. Fagan
- Department of Geography and Environmental SystemsUniversity of Maryland, Baltimore County Baltimore Maryland
| | - J. Leighton Reid
- School of Plant and Environmental SciencesVirginia Tech Blacksburg Virginia
| | - Margaret B. Holland
- Department of Geography and Environmental SystemsUniversity of Maryland, Baltimore County Baltimore Maryland
| | - Justin G. Drew
- Department of Geography and Environmental SystemsUniversity of Maryland, Baltimore County Baltimore Maryland
| | - Rakan A. Zahawi
- Lyon ArboretumUniversity of Hawai'i at Mānoa Honolulu Hawaii
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Affiliation(s)
- J. Leighton Reid
- Center for Conservation and Sustainable Development Missouri Botanical Garden St Louis Missouri 63110 USA
| | - Matthew E. Fagan
- Department of Geography and Environmental Systems University of Maryland Baltimore County Baltimore Maryland 21250 USA
| | - James Lucas
- Department of Biology Washington University in St Louis St Louis Missouri 63130 USA
| | - Joshua Slaughter
- Department of Geography and Environmental Systems University of Maryland Baltimore County Baltimore Maryland 21250 USA
| | - Rakan A. Zahawi
- Lyon Arboretum University of Hawai'i at Mānoa Honolulu Hawai'i 96822 USA
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Reid JL, Fagan ME, Zahawi RA. Positive site selection bias in meta-analyses comparing natural regeneration to active forest restoration. Sci Adv 2018; 4:eaas9143. [PMID: 29774239 PMCID: PMC5955619 DOI: 10.1126/sciadv.aas9143] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 03/28/2018] [Indexed: 05/07/2023]
Abstract
Several recent meta-analyses have aimed to determine whether natural regeneration is more effective at recovering tropical forests than active restoration (for example, tree planting). We reviewed this literature and found that comparisons between strategies are biased by positive site selection. Studies of natural forest regeneration are generally conducted at sites where a secondary forest was already present, whereas tree planting studies are done in a broad range of site conditions, including non-forested sites that may not have regenerated in the absence of planting. Thus, a level of success in forest regeneration is guaranteed for many studies representing natural regeneration, but not for those representing active restoration. The complexity of optimizing forest restoration is best addressed by paired experimentation at the same site, replicated across landscapes. Studies that have taken this approach reach different conclusions than those arising from meta-analyses; the results of paired experimental comparisons emphasize that natural regeneration is a highly variable process and that active restoration and natural regeneration are complementary strategies.
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Affiliation(s)
- J. Leighton Reid
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO 63110, USA
- Corresponding author.
| | - Matthew E. Fagan
- Department of Geography and Environmental Systems, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
| | - Rakan A. Zahawi
- Lyon Arboretum, University of Hawaii at Mānoa, 3860 Mānoa Road, Honolulu, HI 96822, USA
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Cove MV, Fernandez CM, Alvarez MV, Bird S, Jones DW, Fagan ME. Toucans descend to the forest floor to consume the eggs of ground-nesting birds. Food Webs 2017. [DOI: 10.1016/j.fooweb.2017.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cisneros LM, Fagan ME, Willig MR. Environmental and spatial drivers of taxonomic, functional, and phylogenetic characteristics of bat communities in human-modified landscapes. PeerJ 2016; 4:e2551. [PMID: 27761338 PMCID: PMC5068362 DOI: 10.7717/peerj.2551] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 09/12/2016] [Indexed: 11/20/2022] Open
Abstract
Background Assembly of species into communities following human disturbance (e.g., deforestation, fragmentation) may be governed by spatial (e.g., dispersal) or environmental (e.g., niche partitioning) mechanisms. Variation partitioning has been used to broadly disentangle spatial and environmental mechanisms, and approaches utilizing functional and phylogenetic characteristics of communities have been implemented to determine the relative importance of particular environmental (or niche-based) mechanisms. Nonetheless, few studies have integrated these quantitative approaches to comprehensively assess the relative importance of particular structuring processes. Methods We employed a novel variation partitioning approach to evaluate the relative importance of particular spatial and environmental drivers of taxonomic, functional, and phylogenetic aspects of bat communities in a human-modified landscape in Costa Rica. Specifically, we estimated the amount of variation in species composition (taxonomic structure) and in two aspects of functional and phylogenetic structure (i.e., composition and dispersion) along a forest loss and fragmentation gradient that are uniquely explained by landscape characteristics (i.e., environment) or space to assess the importance of competing mechanisms. Results The unique effects of space on taxonomic, functional and phylogenetic structure were consistently small. In contrast, landscape characteristics (i.e., environment) played an appreciable role in structuring bat communities. Spatially-structured landscape characteristics explained 84% of the variation in functional or phylogenetic dispersion, and the unique effects of landscape characteristics significantly explained 14% of the variation in species composition. Furthermore, variation in bat community structure was primarily due to differences in dispersion of species within functional or phylogenetic space along the gradient, rather than due to differences in functional or phylogenetic composition. Discussion Variation among bat communities was related to environmental mechanisms, especially niche-based (i.e., environmental) processes, rather than spatial mechanisms. High variation in functional or phylogenetic dispersion, as opposed to functional or phylogenetic composition, suggests that loss or gain of niche space is driving the progressive loss or gain of species with particular traits from communities along the human-modified gradient. Thus, environmental characteristics associated with landscape structure influence functional or phylogenetic aspects of bat communities by effectively altering the ways in which species partition niche space.
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Affiliation(s)
- Laura M Cisneros
- Department of Natural Resources and the Environment, University of Connecticut , Storrs , CT , United States
| | - Matthew E Fagan
- Department of Geography and Environmental Systems, University of Maryland Baltimore County , Baltimore , MD , United States
| | - Michael R Willig
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, United States; Center for Environmental Science and Engineering, University of Connecticut, Storrs, CT, United States
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Fagan ME, DeFries RS, Sesnie SE, Arroyo-Mora JP, Chazdon RL. Targeted reforestation could reverse declines in connectivity for understory birds in a tropical habitat corridor. Ecol Appl 2016; 26:1456-1474. [PMID: 27755750 DOI: 10.1890/14-2188] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 10/20/2015] [Accepted: 11/05/2015] [Indexed: 06/06/2023]
Abstract
Re-establishing connectivity between protected areas isolated by habitat clearing is a key conservation goal in the humid tropics. In northeastern Costa Rica, payments for environmental services (PES) and a government ban on deforestation have subsidized forest protection and reforestation in the San Juan-La Selva Biological Corridor (SJLSBC), resulting in a decline in mature forest loss and the expansion of tree plantations. We use field studies and graph models to assess how conservation efforts have altered functional connectivity over the last 25 years for four species of insectivorous understory birds. Field playback studies assessed how reforestation habitat quality affected the willingness of Myrmeciza exsul, Henicorhina leucosticta, Thamnophilus atrinucha, and Glyphorynchus spirurus to travel outside forest habitat for territorial defense. Observed travel distances were greatest in nonnative and native tree plantations with high understory stem density, regardless of overstory composition. In contrast, tree plantations with low stem density had travel responses comparable to open pasture for three of the four bird species. We modeled landscape connectivity for each species using graph models based on varying possible travel distances in tree plantations, gallery forests, and pastures. From 1986 to 2011, connectivity for all species declined in the SJLSBC landscape (5825 km2 ) by 14% to 21% despite only a 4.9% net loss in forest area and the rapid expansion of tree plantations over 2% of the landscape. Plantation placement in the landscape limited their potential facilitation of connectivity because they were located either far from forest cover or within already contiguous forest areas. We mapped current connectivity bottlenecks and identified priority areas for future reforestation. We estimate that reforestation of priority areas could improve connectivity by 2% with only a 1% gain in forest cover, an impressive gain given the small area reforested. Results indicate key locations where spatial targeting of PES within the SJLSBC study region would protect existing forest connectivity and enhance the connectivity benefits of reforestation.
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Affiliation(s)
- Matthew E Fagan
- Biospheric Sciences, Goddard Space Flight Center, NASA, Greenbelt, Maryland 20771, USA
| | - Ruth S DeFries
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, 10th Floor Schermerhorn Extension, New York, New York 10027, USA
| | - Steven E Sesnie
- U.S. Fish and Wildlife Service, P.O. Box 1306, Albuquerque, New Mexico 87103, USA
| | - J Pablo Arroyo-Mora
- Department of Geography, McGill University, 805 Sherbrooke Street, West Montreal, Quebec H3A 2K6, Canada
| | - Robin L Chazdon
- Department of Ecology and Evolutionary Biology, University of Connecticut, U-3043 75 North Eagleville Road, Storrs, Connecticut 06269-3043, USA
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Nowakowski AJ, DeWoody JA, Fagan ME, Willoughby JR, Donnelly MA. Mechanistic insights into landscape genetic structure of two tropical amphibians using field-derived resistance surfaces. Mol Ecol 2015; 24:580-95. [DOI: 10.1111/mec.13052] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 12/13/2014] [Accepted: 12/18/2014] [Indexed: 12/01/2022]
Affiliation(s)
- A. Justin Nowakowski
- Department of Biological Sciences; Florida International University; Miami FL 33199 USA
| | - J. Andrew DeWoody
- Department of Forestry & Natural Resources; Purdue University; West Lafayette IN 47907 USA
- Department of Biological Sciences; Purdue University; West Lafayette IN 47907 USA
| | | | - Janna R. Willoughby
- Department of Forestry & Natural Resources; Purdue University; West Lafayette IN 47907 USA
| | - Maureen A. Donnelly
- Department of Biological Sciences; Florida International University; Miami FL 33199 USA
- College of Arts and Sciences; Florida International University; Miami FL 33199 USA
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13
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Cisneros LM, Fagan ME, Willig MR. Effects of human-modified landscapes on taxonomic, functional and phylogenetic dimensions of bat biodiversity. DIVERS DISTRIB 2014. [DOI: 10.1111/ddi.12277] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Laura M. Cisneros
- Department of Ecology and Evolutionary Biology; University of Connecticut; 75 North Eagleville Road Storrs CT 06269-3043 USA
- Center for Environmental Sciences and Engineering; University of Connecticut; 3107 Horsebarn Hill Road Storrs CT 06269-4210 USA
| | - Matthew E. Fagan
- Department of Ecology, Evolution, and Environmental Biology; Columbia University; 1200 Amsterdam Avenue New York NY 10027 USA
| | - Michael R. Willig
- Department of Ecology and Evolutionary Biology; University of Connecticut; 75 North Eagleville Road Storrs CT 06269-3043 USA
- Center for Environmental Sciences and Engineering; University of Connecticut; 3107 Horsebarn Hill Road Storrs CT 06269-4210 USA
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Cisneros LM, Fagan ME, Willig MR. Season-specific and guild-specific effects of anthropogenic landscape modification on metacommunity structure of tropical bats. J Anim Ecol 2014; 84:373-85. [DOI: 10.1111/1365-2656.12299] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 09/26/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Laura M. Cisneros
- Department of Ecology and Evolutionary Biology; University of Connecticut; 75 North Eagleville Road Storrs CT 06269-3043 USA
- Center for Environmental Sciences and Engineering; University of Connecticut; 3107 Horsebarn Hill Road Storrs CT 06269-4210 USA
| | - Matthew E. Fagan
- Department of Ecology, Evolution, and Environmental Biology; Columbia University; 1200 Amsterdam Avenue New York NY 10027 USA
| | - Michael R. Willig
- Department of Ecology and Evolutionary Biology; University of Connecticut; 75 North Eagleville Road Storrs CT 06269-3043 USA
- Center for Environmental Sciences and Engineering; University of Connecticut; 3107 Horsebarn Hill Road Storrs CT 06269-4210 USA
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Cisneros LM, Fagan ME, Willig MR. Season-specific and guild-specific effects of anthropogenic landscape modification on metacommunity structure of tropical bats. J Anim Ecol 2014. [PMID: 25283305 DOI: 10.1111/1365‐2656.12299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fragmentation per se due to human land conversion is a landscape-scale phenomenon. Accordingly, assessment of distributional patterns across a suite of potentially connected communities (i.e. metacommunity structure) is an appropriate approach for understanding the effects of landscape modification and complements the plethora of fragmentation studies that have focused on local community structure. To date, metacommunity structure within human-modified landscapes has been assessed with regard to nestedness along species richness gradients. This is problematic because there is little support that species richness gradients are associated with the factors moulding species distributions. More importantly, many alternative patterns are possible, and different patterns may manifest during different seasons and for different guilds because of variation in resource availability and resource requirements of taxa. We determined the best-fit metacommunity structure of a phyllostomid bat assemblage, frugivore ensemble, and gleaning animalivore ensemble within a human-modified landscape in the Caribbean lowlands of Costa Rica during the dry and wet seasons to elucidate important structuring mechanisms. Furthermore, we identified the landscape characteristics associated with the latent gradient underlying metacommunity structure. We discriminated among multiple metacommunity structures by assessing coherence, range turnover, and boundary clumping of an ordinated site-by-species matrix. We identified the landscape characteristics associated with the latent gradient underlying metacommunity structure via hierarchical partitioning. Metacommunity structure was never nested nor structured along a richness gradient. The phyllostomid assemblage and frugivore ensemble exhibited Gleasonian structure (range turnover along a common gradient) during the dry season and Clementsian structure (range turnover and shared boundaries along a common gradient) during the wet season. Distance between forest patches and forest edge density structured the phyllostomid metacommunity during the dry and wet seasons, respectively. Proportion of pasture and forest patch density structured the frugivore metacommunity during the dry season. Gleaning animalivores exhibited chequerboard structure (mutually exclusive species pairs) during the dry season and random structure during the wet season. Metacommunity structure was likely mediated by differential resource use or interspecific relationships. Furthermore, the interaction between landscape characteristics and seasonal variation in resources resulted in season-specific and guild-specific distributional patterns.
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Affiliation(s)
- Laura M Cisneros
- Department of Ecology and Evolutionary Biology, University of Connecticut, 75 North Eagleville Road, Storrs, CT, 06269-3043, USA.,Center for Environmental Sciences and Engineering, University of Connecticut, 3107 Horsebarn Hill Road, Storrs, CT, 06269-4210, USA
| | - Matthew E Fagan
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, 1200 Amsterdam Avenue, New York, NY, 10027, USA
| | - Michael R Willig
- Department of Ecology and Evolutionary Biology, University of Connecticut, 75 North Eagleville Road, Storrs, CT, 06269-3043, USA.,Center for Environmental Sciences and Engineering, University of Connecticut, 3107 Horsebarn Hill Road, Storrs, CT, 06269-4210, USA
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