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Sommer B, Hodge JM, Lachs L, Cant J, Pandolfi JM, Beger M. Decadal demographic shifts and size-dependent disturbance responses of corals in a subtropical warming hotspot. Sci Rep 2024; 14:6327. [PMID: 38491152 PMCID: PMC10943097 DOI: 10.1038/s41598-024-56890-w] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 03/12/2024] [Indexed: 03/18/2024] Open
Abstract
Long-term demographic studies at biogeographic transition zones can elucidate how body size mediates disturbance responses. Focusing on subtropical reefs in eastern Australia, we examine trends in the size-structure of corals with contrasting life-histories and zoogeographies surrounding the 2016 coral bleaching event (2010-2019) to determine their resilience and recovery capacity. We document demographic shifts, with disproportionate declines in the number of small corals and long-term persistence of larger corals. The incidence of bleaching (Pocillopora, Turbinaria) and partial mortality (Acropora, Pocillopora) increased with coral size, and bleached corals had greater risk of partial mortality. While endemic Pocillopora experienced marked declines, decadal stability of Turbinaria despite bleaching, coupled with abundance increase and bleaching resistance in Acropora indicate remarkable resilience of these taxa in the subtropics. Declines in the number of small corals and variable associations with environmental drivers indicate bottlenecks to recovery mediated by inhibitory effects of thermal extremes for Pocillopora (heat stress) and Acropora (heat and cold stress), and stimulatory effects of chlorophyll-a for Turbinaria. Although our study reveals signs of resilience, it foreshadows the vulnerability of subtropical corals to changing disturbance regimes that include marine heatwaves. Disparity in population dynamics suggest that subtropical reefs are ecologically distinct from tropical coral reefs.
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Affiliation(s)
- Brigitte Sommer
- School of Life and Environmental Science, The University of Sydney, Sydney, NSW, 2006, Australia.
| | - Jessica M Hodge
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
- Maldives Underwater Initiative, Six Senses Laamu, Olhuveli Island, Laamu Atoll, Republic of Maldives
| | - Liam Lachs
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - James Cant
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
- Centre for Biological Diversity, University of St Andrews, St Andrews, KY16 9TH, Scotland, UK
| | - John M Pandolfi
- School of the Environment, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Maria Beger
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
- Centre for Biodiversity and Conservation Science, School of Biological Sciences, University of Queensland, Brisbane, QLD, 4072, Australia
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2
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Cantwell-Jones A, Tylianakis JM, Larson K, Gill RJ. Using individual-based trait frequency distributions to forecast plant-pollinator network responses to environmental change. Ecol Lett 2024; 27:e14368. [PMID: 38247047 DOI: 10.1111/ele.14368] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 01/02/2024] [Accepted: 01/04/2024] [Indexed: 01/23/2024]
Abstract
Determining how and why organisms interact is fundamental to understanding ecosystem responses to future environmental change. To assess the impact on plant-pollinator interactions, recent studies have examined how the effects of environmental change on individual interactions accumulate to generate species-level responses. Here, we review recent developments in using plant-pollinator networks of interacting individuals along with their functional traits, where individuals are nested within species nodes. We highlight how these individual-level, trait-based networks connect intraspecific trait variation (as frequency distributions of multiple traits) with dynamic responses within plant-pollinator communities. This approach can better explain interaction plasticity, and changes to interaction probabilities and network structure over spatiotemporal or other environmental gradients. We argue that only through appreciating such trait-based interaction plasticity can we accurately forecast the potential vulnerability of interactions to future environmental change. We follow this with general guidance on how future studies can collect and analyse high-resolution interaction and trait data, with the hope of improving predictions of future plant-pollinator network responses for targeted and effective conservation.
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Affiliation(s)
- Aoife Cantwell-Jones
- Georgina Mace Centre for The Living Planet, Department of Life Sciences, Silwood Park, Imperial College London, Ascot, UK
| | - Jason M Tylianakis
- Georgina Mace Centre for The Living Planet, Department of Life Sciences, Silwood Park, Imperial College London, Ascot, UK
- Bioprotection Aotearoa, School of Biological Sciences, Private Bag 4800, University of Canterbury, Christchurch, New Zealand
| | - Keith Larson
- Climate Impacts Research Centre, Department of Ecology and Environmental Sciences, Umeå University, Umeå, Sweden
| | - Richard J Gill
- Georgina Mace Centre for The Living Planet, Department of Life Sciences, Silwood Park, Imperial College London, Ascot, UK
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3
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Cant J, Reimer JD, Sommer B, Cook KM, Kim SW, Sims CA, Mezaki T, O'Flaherty C, Brooks M, Malcolm HA, Pandolfi JM, Salguero‐Gómez R, Beger M. Coral assemblages at higher latitudes favor short-term potential over long-term performance. Ecology 2023; 104:e4138. [PMID: 37458125 PMCID: PMC10909567 DOI: 10.1002/ecy.4138] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 06/02/2023] [Accepted: 06/14/2023] [Indexed: 07/18/2023]
Abstract
The persistent exposure of coral assemblages to more variable abiotic regimes is assumed to augment their resilience to future climatic variability. Yet, while the determinants of coral population resilience across species remain unknown, we are unable to predict the winners and losers across reef ecosystems exposed to increasingly variable conditions. Using annual surveys of 3171 coral individuals across Australia and Japan (2016-2019), we explore spatial variation across the short- and long-term dynamics of competitive, stress-tolerant, and weedy assemblages to evaluate how abiotic variability mediates the structural composition of coral assemblages. We illustrate how, by promoting short-term potential over long-term performance, coral assemblages can reduce their vulnerability to stochastic environments. However, compared to stress-tolerant, and weedy assemblages, competitive coral taxa display a reduced capacity for elevating their short-term potential. Accordingly, future climatic shifts threaten the structural complexity of coral assemblages in variable environments, emulating the degradation expected across global tropical reefs.
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Affiliation(s)
- James Cant
- Centre for Biological DiversityUniversity of St AndrewsSt AndrewsUK
- School of Biology, Faculty of Biological SciencesUniversity of LeedsLeedsUK
| | - James D. Reimer
- Molecular Invertebrate Systematics and Ecology LaboratoryGraduate School of Engineering and Science, University of the RyukyusNishiharaJapan
- Tropical Biosphere Research CentreUniversity of the RyukyusNishiharaJapan
| | - Brigitte Sommer
- School of Life and Environmental ScienceThe University of SydneyCamperdownNew South WalesAustralia
- School of Life SciencesUniversity of Technology SydneyUltimoNew South WalesAustralia
| | - Katie M. Cook
- School of Biology, Faculty of Biological SciencesUniversity of LeedsLeedsUK
- National Institute of Water and Atmospheric ResearchHamiltonNew Zealand
| | - Sun W. Kim
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological SciencesThe University of QueenslandBrisbaneQueenslandAustralia
| | - Carrie A. Sims
- Smithsonian Tropical Research InstitutePanama CityRepublic of Panama
| | - Takuma Mezaki
- Kuroshio Biological Research Foundation, Nishidomari, Otsuki‐choKochiJapan
| | | | - Maxime Brooks
- School of Biology, Faculty of Biological SciencesUniversity of LeedsLeedsUK
| | - Hamish A. Malcolm
- Fisheries Research, Department of Primary IndustriesCoffs HarbourNew South WalesAustralia
| | - John M. Pandolfi
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological SciencesThe University of QueenslandBrisbaneQueenslandAustralia
| | - Roberto Salguero‐Gómez
- Department of ZoologyUniversity of OxfordOxfordUK
- Centre for Biodiversity and Conservation Science, School of Biological SciencesUniversity of QueenslandBrisbaneQueenslandAustralia
- Max Planck Institute for Demographic ResearchRostockGermany
| | - Maria Beger
- School of Biology, Faculty of Biological SciencesUniversity of LeedsLeedsUK
- Centre for Biodiversity and Conservation Science, School of Biological SciencesUniversity of QueenslandBrisbaneQueenslandAustralia
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4
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Strampelli P, Henschel P, Searle CE, Macdonald DW, Dickman AJ. Spatial co-occurrence patterns of sympatric large carnivores in a multi-use African system. PLoS One 2023; 18:e0280420. [PMID: 36662874 PMCID: PMC9858824 DOI: 10.1371/journal.pone.0280420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 01/02/2023] [Indexed: 01/21/2023] Open
Abstract
Interspecific interactions can be a key driver of habitat use, and must be accounted for in conservation planning. However, spatial partitioning between African carnivores, and how this varies with scale, remains poorly understood. Furthermore, most studies have taken place within small or highly protected areas, rather than in the heterogeneous, mixed-use landscapes characteristic of much of modern Africa. Here, we provide one of the first empirical investigations into population-level competitive interactions among an African large carnivore guild. We collected detection/non-detection data for an eastern African large carnivore guild in Tanzania's Ruaha-Rungwa conservation landscape, over an area of ~45,000 km2. We then applied conditional co-occupancy models to investigate co-occurrence between lion, leopard, and African wild dog, at two biologically meaningful scales. Co-occurrence patterns of cheetah and spotted hyaena could not be modelled. After accounting for habitat and detection effects, we found some evidence of wild dog avoidance of lion at the home range scale, and strong evidence of fine-scale avoidance. We found no evidence of interspecific exclusion of leopard by lion; rather, positive associations were observed at both scales, suggesting shared habitat preferences. We found little evidence of leopard habitat use being affected by wild dog. Our findings also reveal some interspecific effects on species detection, at both scales. In most cases, habitat use was driven more strongly by other habitat effects, such as biotic resources or anthropogenic pressures, than by interspecific pressures, even where evidence of the latter was present. Overall, our results help shed light on interspecific effects within an assemblage that has rarely been examined at this scale. We also demonstrate the effectiveness of sign-based co-occurrence modelling to describe interspecific spatial patterns of sympatric large carnivores across large scales. We conclude by discussing the implications of our findings for large carnivore conservation in modern African systems.
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Affiliation(s)
- Paolo Strampelli
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
- Lion Landscapes, Iringa, Tanzania
- Panthera, New York, NY, United States of America
| | | | - Charlotte E. Searle
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
- Lion Landscapes, Iringa, Tanzania
| | - David W. Macdonald
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
| | - Amy J. Dickman
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
- Lion Landscapes, Iringa, Tanzania
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5
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Gibson SM, Bateman MD, Murton JB, Barrows TT, Fifield LK, Gibbard PL. Timing and dynamics of Late Wolstonian Substage 'Moreton Stadial' (MIS 6) glaciation in the English West Midlands, UK. R Soc Open Sci 2022; 9:220312. [PMID: 35774135 PMCID: PMC9240686 DOI: 10.1098/rsos.220312] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/23/2022] [Indexed: 05/03/2023]
Abstract
Glaciation during the late Middle Pleistocene is widely recognized across continental northwest Europe, but its extent and palaeoenvironmental significance in the British Isles are disputed. Although glaciogenic sediments at Wolston, Warwickshire, in the English West Midlands, have been used to define the stratotype of the Wolstonian Stage, their age has been variably assigned between marine isotope stages (MIS) 12 and 6. Here we present sedimentological and stratigraphical observations from five sites across the English West Midlands whose chronology is constrained by new luminescence ages from glaciofluvial sediments, supplemented by cosmogenic 36Cl exposure dating of erratic boulders. The ages suggest that between 199 ± 5 and 147 ± 2.5 ka the British Ice Sheet advanced into the English West Midlands as far south as Moreton-in-Marsh, Gloucestershire. This advance is assigned to the Moreton Stadial of the Late Wolstonian Substage. Dating of the glaciation to this substage allows correlation of the Moreton Stadial glacial deposits in the English West Midlands with those of the Drenthe Stadial during the Late Saalian Substage across continental northwest Europe.
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Affiliation(s)
- Sebastian M. Gibson
- Cambridge Quaternary, Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK
| | - Mark D. Bateman
- Department of Geography, University of Sheffield, Winter Street, Sheffield S10 2TN, UK
| | - Julian B. Murton
- Department of Geography, University of Sussex, Falmer, Brighton, BN1 9QJ, UK
| | - Timothy T. Barrows
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Australia
- School of the Environment, Geography and Geosciences, University of Portsmouth, UK
| | - L. Keith Fifield
- Department of Nuclear Physics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200, Australia
| | - Philip L. Gibbard
- Cambridge Quaternary, Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK
- Scott Polar Research Institute, University of Cambridge, Lensfield Road, Cambridge CB2 1ER, UK
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6
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Marsh CD, Hill RA, Nowak MG, Hankinson E, Abdullah A, Gillingham P, Korstjens AH. Measuring and modelling microclimatic air temperature in a historically degraded tropical forest. Int J Biometeorol 2022; 66:1283-1295. [PMID: 35357567 PMCID: PMC9132844 DOI: 10.1007/s00484-022-02276-4] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 03/17/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Climate change is predicted to cause widespread disruptions to global biodiversity. Most climate models are at the macroscale, operating at a ~ 1 km resolution and predicting future temperatures at 1.5-2 m above ground level, making them unable to predict microclimates at the scale that many organisms experience temperature. We studied the effects of forest structure and vertical position on microclimatic air temperature within forest canopy in a historically degraded tropical forest in Sikundur, Northern Sumatra, Indonesia. We collected temperature measurements in fifteen plots over 20 months, alongside vegetation structure data from the same fifteen 25 × 25 m plots. We also performed airborne surveys using an unmanned aerial vehicle (UAV) to record canopy structure remotely, both over the plot locations and a wider area. We hypothesised that old-growth forest structure would moderate microclimatic air temperature. Our data showed that Sikundur is a thermally dynamic environment, with simultaneously recorded temperatures at different locations within the canopy varying by up to ~ 15 °C. Our models (R2 = 0.90 to 0.95) showed that temperature differences between data loggers at different sites were largely determined by variation in recording height and the amount of solar radiation reaching the topmost part of the canopy, although strong interactions between these abiotic factors and canopy structure shaped microclimate air temperature variation. The impacts of forest degradation have smaller relative influence on models of microclimatic air temperature than abiotic factors, but the loss of canopy density increases temperature. This may render areas of degraded tropical forests unsuitable for some forest-dwelling species with the advent of future climate change.
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Affiliation(s)
- Christopher D Marsh
- Department of Life and Environmental Sciences, Bournemouth University, Poole, UK.
- Department of Biology, University of New Mexico, Albuquerque, NM, USA.
| | - Ross A Hill
- Department of Life and Environmental Sciences, Bournemouth University, Poole, UK
| | - Matthew G Nowak
- The PanEco Foundation - Sumatran Orangutan Conservation Programme, Chileweg 5, Berg Am Irchel, Switzerland
- Department of Anthropology, Southern Illinois University, Carbondale, IL, USA
| | - Emma Hankinson
- Department of Life and Environmental Sciences, Bournemouth University, Poole, UK
| | - Abdullah Abdullah
- Department of Biology, Universitas Syiah Kuala, Banda Aceh, Aceh, Indonesia
| | - Phillipa Gillingham
- Department of Life and Environmental Sciences, Bournemouth University, Poole, UK
| | - Amanda H Korstjens
- Department of Life and Environmental Sciences, Bournemouth University, Poole, UK
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7
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Seary R, Spencer T, Bithell M, McOwen C, Ota Y. Defining mangrove-fisheries: A typology from the Perancak Estuary, Bali, Indonesia. PLoS One 2021; 16:e0249173. [PMID: 33882056 PMCID: PMC8059815 DOI: 10.1371/journal.pone.0249173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 03/12/2021] [Indexed: 11/19/2022] Open
Abstract
This study develops a definition of what mangrove-fisheries can encompass, incorporating a broad range of their possible characteristics. A detailed case study was conducted to develop a typology of mangrove-fishing in the Perancak Estuary, Bali, Indonesia, using interview surveys to investigate the fishing activities associated with mangroves. This case study demonstrated the complexity that a mangrove-fishery can entail, where fishing is connected to the mangrove forest by fishers of multiple sectors, functions, locations and temporal scales. Through a comparison with other mangrove-fishing communities in Bali, it also highlighted that mangrove-fisheries are variable even when in close proximity. With particular reference to this case study, a framework was developed as a flexible tool for identifying the multiple dimensions of a mangrove-fishery in a local context. Following this framework should encourage researchers and managers to look outside of the groups of fishers traditionally expected to benefit from mangrove fishing. This will enable the development of a broader definition of mangrove-fisheries in a site specific way. Identifying the full scope of fishers that contribute to or benefit from a mangrove-fishery is the first step towards building management measures that reflect the interests of groups of fishers that may otherwise remain under-represented. This is in line with international efforts for sustainability, especially in promoting small-scale fishers’ access to sustainable resources under the UN Sustainable Development Goals.
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Affiliation(s)
- Rachel Seary
- Cambridge Coastal Research Unit, Department of Geography, University of Cambridge, Cambridge, United Kingdom
- UN Environment Programme World Conservation Monitoring Centre (UNEP-WCMC), Cambridge, United Kingdom
- * E-mail:
| | - Tom Spencer
- Cambridge Coastal Research Unit, Department of Geography, University of Cambridge, Cambridge, United Kingdom
| | - Mike Bithell
- Cambridge Coastal Research Unit, Department of Geography, University of Cambridge, Cambridge, United Kingdom
| | - Chris McOwen
- UN Environment Programme World Conservation Monitoring Centre (UNEP-WCMC), Cambridge, United Kingdom
| | - Yoshitaka Ota
- School of Marine & Environmental Affairs, College of The Environment, University of Washington, Seattle, WA, United States of America
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Arnaud M, Baird AJ, Morris PJ, Dang TH, Nguyen TT. Sensitivity of mangrove soil organic matter decay to warming and sea level change. Glob Chang Biol 2020; 26:1899-1907. [PMID: 31750606 DOI: 10.1111/gcb.14931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/20/2019] [Indexed: 06/10/2023]
Abstract
Mangroves are among the world's most carbon-dense ecosystems, but they are threatened by rapid climate change and rising sea levels. The accumulation and decomposition of soil organic matter (SOM) are closely tied to mangroves' carbon sink functions and resistance to rising sea levels. However, few studies have investigated the response of mangrove SOM dynamics to likely future environmental conditions. We quantified how mangrove SOM decay is affected by predicted global warming (+4°C), sea level changes (simulated by altering of the inundation duration to 0, 2, and 6 hr/day), and their interaction. Whilst changes in inundation duration between 2 and 6 hr/day did not affect SOM decay, the treatment without inundation led to a 60% increase. A warming of 4°C caused SOM decay to increase by 21%, but longer inundation moderated this temperature-driven increase. Our results indicate that (a) sea level rise is unlikely to decrease the SOM decay rate, suggesting that previous mangrove elevation gain, which has allowed mangroves to persist in areas of sea level rise, might result from changes in root production and/or mineral sedimentation; (b) sea level fall events, predicted to double in frequency and area, will cause periods of intensified SOM decay; (c) changing tidal regimes in mangroves due to sea level rise might attenuate increases in SOM decay caused by global warming. Our results have important implications for forecasting mangrove carbon dynamics and the persistence of mangroves and other coastal wetlands under future scenarios of climate change.
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Affiliation(s)
- Marie Arnaud
- School of Geography, University of Leeds, Leeds, UK
| | - Andy J Baird
- School of Geography, University of Leeds, Leeds, UK
| | | | - Thuong Huyen Dang
- Faculty of Geology and Petroleum Engineering, Ho Chí Minh City University of Technology (HCMUT), Ho Chí Minh, Vietnam
| | - Tai Tue Nguyen
- Faculty of Geology, VNU University of Science, Vietnam National University, Hanoi, Ha Noi, Vietnam
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Thorpe CJ, Lewis TR, Fisher MC, Wierzbicki CJ, Kulkarni S, Pryce D, Davies L, Watve A, Knight ME. Climate structuring of Batrachochytrium dendrobatidis infection in the threatened amphibians of the northern Western Ghats, India. R Soc Open Sci 2018; 5:180211. [PMID: 30110422 PMCID: PMC6030269 DOI: 10.1098/rsos.180211] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 05/04/2018] [Indexed: 05/08/2023]
Abstract
Batrachochytrium dendrobatidis (Bd) is a pathogen killing amphibians worldwide. Its impact across much of Asia is poorly characterized. This study systematically surveyed amphibians for Bd across rocky plateaus in the northern section of the Western Ghats biodiversity hotspot, India, including the first surveys of the plateaus in the coastal region. These ecosystems offer an epidemiological model system since they are characterized by differing levels of connectivity, edaphic and climatic conditions, and anthropogenic stressors. One hundred and eighteen individuals of 21 species of Anura and Apoda on 13 plateaus ranging from 67 to 1179 m above sea level and 15.89 to 17.92° North latitude were sampled. Using qPCR protocols, 79% of species and 27% of individuals tested were positive for Bd. This is the first record of Bd in caecilians in India, the Critically Endangered Xanthophryne tigerina and Endangered Fejervarya cf. sahyadris. Mean site prevalence was 28.15%. Prevalence below the escarpment was 31.2% and 25.4% above. The intensity of infection (GE) showed the reverse pattern. Infection may be related to elevational temperature changes, thermal exclusion, inter-site connectivity and anthropogenic disturbance. Coastal plateaus may be thermal refuges from Bd. Infected amphibians represented a wide range of ecological traits posing interesting questions about transmission routes.
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Affiliation(s)
- Christopher J. Thorpe
- Ecology, Behaviour and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
| | - Todd R. Lewis
- Westfield, 4 Worgret Road, Wareham, Dorset BH20 4PJ, UK
| | - Matthew C. Fisher
- Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, UK
| | - Claudia J. Wierzbicki
- Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, UK
| | - Siddharth Kulkarni
- Department of Biological Sciences, George Washington University, 2121 I St NW, Washington, DC 20052, USA
| | - David Pryce
- Ecology, Behaviour and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
| | - Lewis Davies
- Ecology, Behaviour and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
| | - Aparna Watve
- Tata Institute of Social Sciences, Apsinga Road, PO Box No. 09, Tuljapur 413 601, District-Osmanabad, Maharashtra, India
| | - Mairi E. Knight
- Ecology, Behaviour and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
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10
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Thorpe CJ, Lewis TR, Kulkarni S, Watve A, Gaitonde N, Pryce D, Davies L, Bilton DT, Knight ME. Micro-habitat distribution drives patch quality for sub-tropical rocky plateau amphibians in the northern Western Ghats, India. PLoS One 2018; 13:e0194810. [PMID: 29579111 PMCID: PMC5868820 DOI: 10.1371/journal.pone.0194810] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 03/09/2018] [Indexed: 12/04/2022] Open
Abstract
The importance of patch quality for amphibians is frequently overlooked in distribution models. Here we demonstrate that it is highly important for the persistence of endemic and endangered amphibians found in the threatened and fragile ecosystems that are the rocky plateaus in Western Maharashtra, India. These plateaus are ferricretes of laterite and characterise the northern section of the Western Ghats/Sri Lanka Biodiversity Hotspot, the eighth most important global hotspot and one of the three most threatened by population growth. We present statistically supported habitat associations for endangered and data-deficient Indian amphibians, demonstrating significant relationships between individual species and their microhabitats. Data were collected during early monsoon across two seasons. Twenty-one amphibian taxa were identified from 14 lateritic plateaus between 67 and 1179m above sea level. Twelve of the study taxa had significant associations with microhabitats using a stepwise analysis of the AICc subroutine (distLM, Primer-e, v7). Generalist taxa were associated with increased numbers of microhabitat types. Non-significant associations are reported for the remaining 9 taxa. Microhabitat distribution was spatially structured and driven by climate and human activity. Woody plants were associated with 44% of high-elevation taxa. Of the 8 low-elevation taxa 63% related to water bodies and 60% of those were associated with pools. Rock size and abundance were important for 33% of high elevation specialists. Three of the 4 caecilians were associated with rocks in addition to soil and stream presence. We conclude the plateaus are individualistic patches whose habitat quality is defined by their microhabitats within climatic zones.
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Affiliation(s)
- Christopher J. Thorpe
- Ecology and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, United Kingdom
- * E-mail: (CJT); (TRL)
| | - Todd R. Lewis
- Westfield, Wareham, Dorset, United Kingdom
- * E-mail: (CJT); (TRL)
| | | | - Aparna Watve
- Tata Institute of Social Sciences, Taljapur, Osmanabad, Maharashtra, India
| | - Nikhil Gaitonde
- National Centre for Biological Sciences, Rajiv Gandhi Nagar, Kodigehalli, Bengaluru, Karnataka, India
| | - David Pryce
- Ecology and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, United Kingdom
| | - Lewis Davies
- Ecology and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, United Kingdom
| | - David T. Bilton
- Ecology and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, United Kingdom
| | - Mairi E. Knight
- Ecology and Evolution Research Group, School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, United Kingdom
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McGowan S, Gunn HV, Whiteford EJ, John Anderson N, Jones VJ, Law AC. Functional attributes of epilithic diatoms for palaeoenvironmental interpretations in South-West Greenland lakes. J Paleolimnol 2017; 60:273-298. [PMID: 30996516 PMCID: PMC6435045 DOI: 10.1007/s10933-017-9968-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 04/28/2017] [Indexed: 06/09/2023]
Abstract
Benthic diatoms are commonly used for palaeoenvironmental reconstruction in Arctic regions, but interpretation of their ecology remains challenging. We studied epilithic diatom assemblages from the shallow margins of 19 lakes from three areas (coast-inland-ice sheet margin) along a climate gradient in Kangerlussuaq, West Greenland during two periods; shortly after ice-off (spring) and in the middle of the growth season (summer). We aimed to understand the distribution of Arctic epilithic diatoms in relation to water chemistry gradients during the two seasons, to investigate their incorporation into lake sediments and to assess their applicability as palaeoenvironmental indicators. Diatoms were correlated with nutrients in the spring and alkalinity/major ions in the summer, when nutrients were depleted; approximately half of the variance explained was independent of spatial factors. When categorised by functional attributes, diatom seasonal succession differed among regions with the most obvious changes in inland lakes where summer temperatures are warmer, organic nutrient processing is prevalent and silicate is limiting. These conditions led to small, motile and adnate diatoms being abundant in inland lakes during the summer (Nitzschia spp., Encyonopsis microcephala), as these functional attributes are suited to living within complex mats of non-siliceous microbial biofilms. Seasonal succession in silica-rich lakes at the coast was less pronounced and assemblages included Tabellaria flocculosa (indicating more acidic conditions) and Hannaea arcus (indicating input from inflowing rivers). The nitrogen-fixing diatom Epithemia sorex increased from the coast to the ice sheet, negatively correlating with a gradient of reactive nitrogen. The presence of this diatom in Holocene sediment records alongside cyanobacterial carotenoids during arid periods of low nitrogen delivery, suggests that it is a useful indicator of nitrogen limitation. Nitzschia species appear to be associated with high concentrations of organic carbon and heterotrophy, but their poor representation in West Greenland lake sediments due to taphonomic processes limits their palaeoenvironmental application in this region. Proportions of epilithic taxa in lake sediment records of coastal lakes increased during some wetter periods of the Holocene, suggesting that snowpack-derived nutrient delivery may offer diatom taxa living at lake margins a competitive advantage over planktonic diatoms during the "moating" ice melt period. Thus, further research investigating linkages between epilithic diatoms, snowpack and nutrient delivery in seasonally frozen lakes is recommended as these taxa live on the 'front-line' during the spring and may be especially sensitive to changes in snowmelt conditions.
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Affiliation(s)
- Suzanne McGowan
- School of Geography, University of Nottingham, University Park, Nottingham, NG7 2RD UK
- School of Geography, University of Nottingham, Malaysia Campus, 43500 Semenyih, Selangor Darul Ehsan Malaysia
| | - Hazel V. Gunn
- School of Geography, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Erika J. Whiteford
- Department of Geography, Loughborough University, Loughborough, LE11 3TU Leicestershire UK
| | - N. John Anderson
- Department of Geography, Loughborough University, Loughborough, LE11 3TU Leicestershire UK
| | - Vivienne J. Jones
- Environmental Change Research Centre, Department of Geography, University College London, Gower Street, London, WC1E 6BT UK
| | - Antonia C. Law
- School of Physical and Geographical Sciences, Keele University, William Smith Building, Keele, Staffs ST55BG UK
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Andradi-Brown DA, Grey R, Hendrix A, Hitchner D, Hunt CL, Gress E, Madej K, Parry RL, Régnier-McKellar C, Jones OP, Arteaga M, Izaguirre AP, Rogers AD, Exton DA. Depth-dependent effects of culling-do mesophotic lionfish populations undermine current management? R Soc Open Sci 2017; 4:170027. [PMID: 28573007 PMCID: PMC5451808 DOI: 10.1098/rsos.170027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 04/27/2017] [Indexed: 05/15/2023]
Abstract
Invasive lionfish (Pterois volitans and P. miles) have spread widely across the western Atlantic and are recognized as a major threat to native marine biodiversity. Although lionfish inhabit both shallow reefs and mesophotic coral ecosystems (MCEs; reefs from 30 to 150 m depth), the primary management response implemented by many countries has been diver-led culling limited to reefs less than 30 m. However, many reef fish undergo ontogenetic migrations, with the largest and therefore most fecund individuals found at greatest depths. Here, we study lionfish density, body size, maturity and dietary patterns across the depth gradient from the surface down to 85 m on heavily culled reefs around Utila, Honduras. We found lionfish at increased densities, body size and weight on MCEs compared with shallow reefs, with MCEs also containing the greatest proportion of actively spawning females, while shallow reefs contained the greatest proportion of immature lionfish. We then compared lionfish behaviour in response to divers on shallow culled and mesophotic unculled Utilan reefs, and on shallow unculled reefs in Tela Bay, on the Honduran mainland. We found that mesophotic lionfish exhibited high alert distances, consistent with individuals previously exposed to culling despite being below the depth limits of removal. In addition, when examining stomach content, we found that fish were the major component of lionfish diets across the depth gradient. Importantly, our results suggest that despite adjacent shallow culling, MCEs retain substantial lionfish populations that may be disproportionately contributing towards continued lionfish recruitment onto the shallow reefs of Utila, potentially undermining current culling-based management.
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Affiliation(s)
- Dominic A. Andradi-Brown
- Department of Zoology, University of Oxford, The Tinbergen Building, South Parks Road, Oxford, OX1 3PS, UK
- Operation Wallacea, Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
- Author for correspondence: Dominic A. Andradi-Brown e-mail:
| | - Rachel Grey
- Operation Wallacea, Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
- College of Charleston, 205 Fort Johnson Road, Charleston, SC 29412, USA
| | - Alicia Hendrix
- Operation Wallacea, Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
| | - Drew Hitchner
- Operation Wallacea, Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
| | - Christina L. Hunt
- Department of Zoology, University of Oxford, The Tinbergen Building, South Parks Road, Oxford, OX1 3PS, UK
- Operation Wallacea, Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
| | - Erika Gress
- Operation Wallacea, Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
| | - Konrad Madej
- Whaleshark and Oceanic Research Center, Main Street, Utila, Bay Islands 34201, Honduras
| | - Rachel L. Parry
- Whaleshark and Oceanic Research Center, Main Street, Utila, Bay Islands 34201, Honduras
| | | | - Owen P. Jones
- Whaleshark and Oceanic Research Center, Main Street, Utila, Bay Islands 34201, Honduras
| | - María Arteaga
- Bay Islands Conservation Association—Utila Chapter, Airport Road, Utila, Bay Islands 34201, Honduras
| | - Andrea P. Izaguirre
- Bay Islands Conservation Association—Utila Chapter, Airport Road, Utila, Bay Islands 34201, Honduras
| | - Alex D. Rogers
- Department of Zoology, University of Oxford, The Tinbergen Building, South Parks Road, Oxford, OX1 3PS, UK
| | - Dan A. Exton
- Operation Wallacea, Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
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Abstract
In the drylands of Africa, pastoralists have been facing new challenges, including those related to environmental shocks and stresses. In northern Kenya, under conditions of reduced rainfall and more frequent droughts, one response has been for pastoralists to focus increasingly on camel herding. Camels have started to be kept at higher altitudes and by people who rarely kept camels before. The development has been understood as a climate change adaptation strategy and as a means to improve climate resilience. Since 2003, development organizations have started to further the trend by distributing camels in the region. Up to now, little has been known about the nature of, reasons for, or ramifications of the increased reliance on camels. The paper addresses these questions and concludes that camels improve resilience in this dryland region, but only under certain climate change scenarios, and only for some groups.
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Affiliation(s)
- Elizabeth E. Watson
- Department of Geography, University of Cambridge, Downing Place, Cambridge, CB2 3EN UK
| | - Hassan H. Kochore
- Max Planck Institute for Social Anthropology, Advokatenweg 36, 06114 Halle (Saale), Germany
| | - Bulle Hallo Dabasso
- Kenya Agricultural and Livestock Research Organisation, P.O. Box 147, Marsabit, Kenya
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