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Yu X, Yu K, Liao Z, Chen B, Qin Z, Liang J, Gao X. Adaptation strategies of relatively high-latitude marginal reef corals in response to severe temperature fluctuations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166439. [PMID: 37604380 DOI: 10.1016/j.scitotenv.2023.166439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 08/18/2023] [Indexed: 08/23/2023]
Abstract
The large seasonal temperature fluctuations caused by global warming and frequent marine heatwaves pose new challenges to survival of relatively high-latitude marginal reef corals. However, the adaptation strategies of high-latitude marginal corals are not fully understood. We employed integrated approach to investigate the response mechanism of hosts, Symbiodiniaceae, and symbiotic bacteria of marginal reef corals Acropora pruinosa and Pavona decussate in response to large seasonal temperature fluctuations. The coral holobiont maintained a high level of immunity to adapt to seasonal pressure by increasing Symbiodiniaceae energy supply. The symbiotic Symbiodiniaceae of two coral was dominated by C1 subgroup, and was stable across seasons. The α-diversity of symbiotic bacteria P. decussata and A. pruinosa in summer was higher than that in winter. The symbiotic bacterial community of two coral reorganized during different seasons. Scleractinian corals improve adaptability to seasonal stress by increasing energy supply to maintain high levels of immunity, increasing symbiotic bacterial α-diversity, and changing dominant bacteria. This study demonstrates the adaptation strategies of marginal reef corals to seasonal temperature fluctuations and provides novel insights into the study of the adaptation of corals and relatively high-latitude coral refuges in the context of global warming and intensified marine heatwaves.
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Affiliation(s)
- Xiaopeng Yu
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, Nanning, China
| | - Kefu Yu
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, Nanning, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China.
| | - Zhiheng Liao
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, Nanning, China
| | - Biao Chen
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, Nanning, China
| | - Zhenjun Qin
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, Nanning, China
| | - Jiayuan Liang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, Nanning, China
| | - Xu Gao
- Guangxi University of Chinese Medicine, Nanning, Guangxi, China
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2
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Chan YKS, Affendi YA, Ang PO, Baria-Rodriguez MV, Chen CA, Chui APY, Giyanto, Glue M, Huang H, Kuo CY, Kim SW, Lam VYY, Lane DJW, Lian JS, Lin SMNN, Lunn Z, Nañola CL, Nguyen VL, Park HS, Suharsono, Sutthacheep M, Vo ST, Vibol O, Waheed Z, Yamano H, Yeemin T, Yong E, Kimura T, Tun K, Chou LM, Huang D. Decadal stability in coral cover could mask hidden changes on reefs in the East Asian Seas. Commun Biol 2023; 6:630. [PMID: 37301948 PMCID: PMC10257672 DOI: 10.1038/s42003-023-05000-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 05/31/2023] [Indexed: 06/12/2023] Open
Abstract
Coral reefs in the Central Indo-Pacific region comprise some of the most diverse and yet threatened marine habitats. While reef monitoring has grown throughout the region in recent years, studies of coral reef benthic cover remain limited in spatial and temporal scales. Here, we analysed 24,365 reef surveys performed over 37 years at 1972 sites throughout East Asia by the Global Coral Reef Monitoring Network using Bayesian approaches. Our results show that overall coral cover at surveyed reefs has not declined as suggested in previous studies and compared to reef regions like the Caribbean. Concurrently, macroalgal cover has not increased, with no indications of phase shifts from coral to macroalgal dominance on reefs. Yet, models incorporating socio-economic and environmental variables reveal negative associations of coral cover with coastal urbanisation and sea surface temperature. The diversity of reef assemblages may have mitigated cover declines thus far, but climate change could threaten reef resilience. We recommend prioritisation of regionally coordinated, locally collaborative long-term studies for better contextualisation of monitoring data and analyses, which are essential for achieving reef conservation goals.
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Affiliation(s)
- Y K S Chan
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore.
| | - Y A Affendi
- Institute of Ocean and Earth Sciences, Universiti Malaya, Kuala Lumpur, Malaysia
| | - P O Ang
- Institute of Space and Earth Information Science, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - M V Baria-Rodriguez
- Marine Science Institute, University of the Philippines Diliman, Quezon, Philippines
| | - C A Chen
- Biodiversity Research Centre, Academia Sinica, Taipei, Taiwan
| | - A P Y Chui
- Institute of Space and Earth Information Science, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Giyanto
- Research Center for Oceanography, National Research and Innovation Agency (BRIN), Jakarta, Indonesia
| | - M Glue
- Fauna & Flora International, Phnom Penh, Cambodia
| | - H Huang
- South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - C-Y Kuo
- Biodiversity Research Centre, Academia Sinica, Taipei, Taiwan
| | - S W Kim
- School of Biological Sciences, The University of Queensland, Brisbane, Australia
| | - V Y Y Lam
- Global Coral Reef Monitoring Network, International Union for the Conservation of Nature, Washington D.C., USA
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, Brisbane, Australia
| | - D J W Lane
- Lee Kong Chian Natural History Museum, National University of Singapore, Singapore, Singapore
- Universiti Brunei Darussalam, Bandar Seri Begawan, Brunei Darussalam
| | - J S Lian
- South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - S M N N Lin
- Fauna & Flora International, Yangon, Myanmar
| | - Z Lunn
- Fauna & Flora International, Yangon, Myanmar
| | - C L Nañola
- University of the Philippines Mindanao, Davao, Philippines
| | - V L Nguyen
- Institute of Oceanography, Vietnam Academy of Science and Technology, Nha Trang, Vietnam
| | - H S Park
- Korean Institute of Ocean Science and Technology, Seoul, South Korea
| | - Suharsono
- Research Center for Oceanography, National Research and Innovation Agency (BRIN), Jakarta, Indonesia
| | - M Sutthacheep
- Department of Biological Sciences, Ramkhamhaeng University, Bangkok, Thailand
| | - S T Vo
- Institute of Oceanography, Vietnam Academy of Science and Technology, Nha Trang, Vietnam
| | - O Vibol
- Department of Fisheries Conservation, Ministry of Agriculture, Phnom Penh, Cambodia
| | - Z Waheed
- Borneo Marine Research Institute, Universiti Malaysia Sabah, Kota Kinabalu, Malaysia
| | - H Yamano
- National Institute for Environmental Studies, Tsukaba, Japan
| | - T Yeemin
- Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand
| | - E Yong
- Reef Check Brunei, Bandar Seri Begawan, Brunei Darussalam
| | - T Kimura
- Global Coral Reef Monitoring Network East Asia Region, Tokyo, Japan
- Palau International Coral Reef Center, Koror, Palau
| | - K Tun
- Global Coral Reef Monitoring Network East Asia Region, Tokyo, Japan
- National Biodiversity Centre, National Parks Board, Singapore, Singapore
| | - L M Chou
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Tropical Marine Science Institute, National University of Singapore, Singapore, Singapore
| | - D Huang
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Lee Kong Chian Natural History Museum, National University of Singapore, Singapore, Singapore
- Tropical Marine Science Institute, National University of Singapore, Singapore, Singapore
- Centre for Nature-based Climate Solutions, National University of Singapore, Singapore, Singapore
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3
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de Souza MR, Caruso C, Ruiz-Jones L, Drury C, Gates RD, Toonen RJ. Importance of depth and temperature variability as drivers of coral symbiont composition despite a mass bleaching event. Sci Rep 2023; 13:8957. [PMID: 37268692 DOI: 10.1038/s41598-023-35425-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 05/17/2023] [Indexed: 06/04/2023] Open
Abstract
Coral reefs are iconic examples of climate change impacts because climate-induced heat stress causes the breakdown of the coral-algal symbiosis leading to a spectacular loss of color, termed 'coral bleaching'. To examine the fine-scale dynamics of this process, we re-sampled 600 individually marked Montipora capitata colonies from across Kāne'ohe Bay, Hawai'i and compared the algal symbiont composition before and after the 2019 bleaching event. The relative proportion of the heat-tolerant symbiont Durusdinium in corals increased in most parts of the bay following the bleaching event. Despite this widespread increase in abundance of Durusdinium, the overall algal symbiont community composition was largely unchanged, and hydrodynamically defined regions of the bay retained their distinct pre-bleaching compositions. We explain ~ 21% of the total variation, of which depth and temperature variability were the most significant environmental drivers of Symbiodiniaceae community composition by site regardless of bleaching intensity or change in relative proportion of Durusdinium. We hypothesize that the plasticity of symbiont composition in corals may be constrained to adaptively match the long-term environmental conditions surrounding the holobiont, despite an individual coral's stress and bleaching response.
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Affiliation(s)
- Mariana Rocha de Souza
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Kāne'ohe, HI, 96744, USA.
| | - Carlo Caruso
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Kāne'ohe, HI, 96744, USA
| | - Lupita Ruiz-Jones
- Chaminade University of Honolulu, 3140 Waialae Ave, Honolulu, HI, 96816, USA
| | - Crawford Drury
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Kāne'ohe, HI, 96744, USA
| | - Ruth D Gates
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Kāne'ohe, HI, 96744, USA
| | - Robert J Toonen
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Kāne'ohe, HI, 96744, USA
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4
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González-Barrios FJ, Estrada-Saldívar N, Pérez-Cervantes E, Secaira-Fajardo F, Álvarez-Filip L. Legacy effects of anthropogenic disturbances modulate dynamics in the world's coral reefs. GLOBAL CHANGE BIOLOGY 2023; 29:3285-3303. [PMID: 36932916 DOI: 10.1111/gcb.16686] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 03/03/2023] [Accepted: 03/07/2023] [Indexed: 05/16/2023]
Abstract
Rapidly changing conditions alter disturbance patterns, highlighting the need to better understand how the transition from pulse disturbances to more persistent stress will impact ecosystem dynamics. We conducted a global analysis of the impacts of 11 types of disturbances on reef integrity using the rate of change of coral cover as a measure of damage. Then, we evaluated how the magnitude of the damage due to thermal stress, cyclones, and diseases varied among tropical Atlantic and Indo-Pacific reefs and whether the cumulative impact of thermal stress and cyclones was able to modulate the responses of reefs to future events. We found that reef damage largely depends on the condition of a reef before a disturbance, disturbance intensity, and biogeographic region, regardless of the type of disturbance. Changes in coral cover after thermal stress events were largely influenced by the cumulative stress of past disturbances and did not depend on disturbance intensity or initial coral cover, which suggests that an ecological memory is present within coral communities. In contrast, the effect of cyclones (and likely other physical impacts) was primarily modulated by the initial reef condition and did not appear to be influenced by previous impacts. Our findings also underscore that coral reefs can recover if stressful conditions decrease, yet the lack of action to reduce anthropogenic impacts and greenhouse gas emissions continues to trigger reef degradation. We uphold that evidence-based strategies can guide managers to make better decisions to prepare for future disturbances.
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Affiliation(s)
- F Javier González-Barrios
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Mexico
| | - Nuria Estrada-Saldívar
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Mexico
| | - Esmeralda Pérez-Cervantes
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Mexico
| | | | - Lorenzo Álvarez-Filip
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Mexico
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5
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Mo S, Chen T, Chen Z, Zhang W, Li S. Marine heatwaves impair the thermal refugia potential of marginal reefs in the northern South China Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 825:154100. [PMID: 35218829 DOI: 10.1016/j.scitotenv.2022.154100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 02/17/2022] [Accepted: 02/19/2022] [Indexed: 06/14/2023]
Abstract
Frequent marine heatwaves (MHWs), concurrent with climate warming, threaten global low-latitude, pristine coral reefs, leading to growing interest in identifying marginal coral reefs (relatively high-latitude and/or turbid reef environments) that can serve as thermal refugia from mass coral bleaching. However, the thermal refugia potential of marginal reefs remains controversial. We evaluated the thermal refugia potential of inshore reefs in the northern South China Sea (nSCS), a globally typical marginal reef system, by characterizing the long-term trend of MHW intensity and frequency and assessing thermal stress during a mass bleaching event in summer 2020. An unprecedented peak intensity of around 20 °C-weeks of cumulative heat stress, associated with a prolonged anomalous western Pacific subtropical high (WPSH) and weakened monsoon activity, induced record-breaking bleaching. The geographical variability of bleaching was strongly related to the extent of heat exposure and satellite-derived temperature anomalies. Under ongoing global warming, the frequency and intensity of MHWs over nSCS coral habitats show a markedly increasing trend, especially during the last decade. Intense MHWs and coral bleaching have already occurred throughout all El Niño-Southern Oscillation (ENSO) phases (e.g., 2010, 2015, and 2020). Climate change has pushed marginal coral reefs to or beyond the limits of their resilience, and frequent MHW events have amplified the increasing risk of thermal stress. There are no long-term thermal refugia for marginal reefs in the nSCS.
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Affiliation(s)
- Shaohua Mo
- Beihai Marine Environmental Monitoring Center Station, State Oceanic Administration, Beihai 536000, China
| | - Tianran Chen
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China.
| | - Zesheng Chen
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
| | - Wenjing Zhang
- South China Sea Information Center, State Oceanic Administration, Guangzhou 510310, China
| | - Shu Li
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
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6
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Cook KM, Yamagiwa H, Beger M, Masucci GD, Ross S, Lee HYT, Stuart‐Smith RD, Reimer JD. A community and functional comparison of coral and reef fish assemblages between four decades of coastal urbanisation and thermal stress. Ecol Evol 2022; 12:e8736. [PMID: 35356574 PMCID: PMC8939291 DOI: 10.1002/ece3.8736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/24/2022] [Accepted: 02/24/2022] [Indexed: 01/29/2023] Open
Abstract
Urbanized coral reefs experience anthropogenic disturbances caused by coastal development, pollution, and nutrient runoff, resulting in turbid, marginal conditions in which only certain species can persist. Mortality effects are exacerbated by increasingly regular thermal stress events, leading to shifts towards novel communities dominated by habitat generalists and species with low structural complexity. There is limited data on the turnover processes that occur due to this convergence of anthropogenic stressors, and how novel urban ecosystems are structured both at the community and functional levels. As such, it is unclear how they will respond to future disturbance events. Here, we examine the patterns of coral reef community change and determine whether ecosystem functions provided by specialist species are lost post‐disturbance. We present a comparison of community and functional trait‐based changes for scleractinian coral genera and reef fish species assemblages subject to coastal development, coastal modification, and mass bleaching between two time periods, 1975–1976 and 2018, in Nakagusuku Bay, Okinawa, Japan. We observed an increase in fish habitat generalists, a dominance shift from branching to massive/sub‐massive corals and increasing site‐based coral genera richness between years. Fish and coral communities significantly reassembled, but functional trait‐based multivariate space remained constant, indicating a turnover of species with similar traits. A compression of coral habitat occurred, with shallow (<5 m) and deep (>8 m) coral genera shifting towards the mid‐depths (5–8 m). We show that although reef species assemblages altered post disturbance, new communities retained similar ecosystem functions. This result could be linked to the stressors experienced by urban reefs, which reflect those that will occur at an increasing frequency globally in the near future. Yet, even after shifts to disturbed communities, these fully functioning reef systems may maintain high conservation value.
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Affiliation(s)
- Katie M. Cook
- School of Biology Faculty of Biological Sciences University of Leeds LeedsUK
| | - Hirotaka Yamagiwa
- Molecular Invertebrate Systematics and Ecology Laboratory Graduate School of Engineering and Science University of the Ryukyus NishiharaJapan
| | - Maria Beger
- School of Biology Faculty of Biological Sciences University of Leeds LeedsUK
- Centre for Biodiversity and Conservation Science School of Biological Sciences The University of Queensland Brisbane QueenslandAustralia
| | - Giovanni Diego Masucci
- Molecular Invertebrate Systematics and Ecology Laboratory Graduate School of Engineering and Science University of the Ryukyus NishiharaJapan
| | - Stuart Ross
- School of Biology Faculty of Biological Sciences University of Leeds LeedsUK
| | - Hui Yian Theodora Lee
- Molecular Invertebrate Systematics and Ecology Laboratory Graduate School of Engineering and Science University of the Ryukyus NishiharaJapan
- Experimental Marine Ecology Laboratory Department of Biological Sciences National University of Singapore SingaporeSingapore
| | - Rick D. Stuart‐Smith
- Institute for Marine and Antarctic Studies University of Tasmania Taroona TasmaniaAustralia
| | - James Davis Reimer
- Molecular Invertebrate Systematics and Ecology Laboratory Graduate School of Engineering and Science University of the Ryukyus NishiharaJapan
- Tropical Biosphere Research Center University of the Ryukyus NishiharaJapan
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7
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Madeira C, Dias M, Ferreira A, Gouveia R, Cabral H, Diniz MS, Vinagre C. Does Predation Exacerbate the Risk of Endosymbiont Loss in Heat Stressed Hermatypic Corals? Molecular Cues Provide Insights Into Species-Specific Health Outcomes in a Multi-Stressor Ocean. Front Physiol 2022; 13:801672. [PMID: 35299660 PMCID: PMC8922028 DOI: 10.3389/fphys.2022.801672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/31/2022] [Indexed: 11/30/2022] Open
Abstract
Ocean warming has been a major driver of coral reef bleaching and mass mortality. Coupled to other biotic pressures, corals’ ability for acclimatization and adaptation may become compromised. Here, we tested the combined effects of warming scenarios (26, 30, and 32°C) and predation (wound vs. no wound) in coral health condition (paleness, bleaching, and mortality), cellular stress responses (heat shock protein 70 kDa Hsp70, total ubiquitin Ub, and total antioxidant capacity TAC), and physiological state (integrated biomarker response index, IBR) of seven Scleractinian coral species, after being exposed for 60 days. Results show that although temperature was the main factor driving coral health condition, thermotolerant species (Galaxea fascicularis, Psammocora contigua, and Turbinaria reniformis) displayed increased paleness, bleaching, and mortality in predation treatments at high temperature, whereas thermosensitive species (Acropora tenuis, Echinopora lamellosa, and Montipora capricornis brown and green morphotypes) all died at 32°C, regardless of predation condition. At the molecular level, results show that there were significant main and interactive effects of species, temperature, and predation in the biomarkers assessed. Temperature affected Hsp70, Ub, and TAC, evidencing the role of protein folding and turnover, as well as reactive oxygen species scavenging in heat stress management. Predation increased Hsp70 and Ub, suggesting the activation of the pro-phenoloxidase system and cytokine activity, whereas the combination of both stressors mainly affected TAC during moderate stress and Ub under severe stress, suggesting that redox balance and defense of homeostasis are crucial in tissue repair at high temperature. IBR levels showed an increasing trend at 32°C in predated coral fragments (although non-significant). We conclude that coral responses to the combination of high temperature and predation pressure display high inter-species variability, but these stressors may pose a higher risk of endosymbiont loss, depending on species physiology and stress intensity.
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Affiliation(s)
- Carolina Madeira
- i4HB – Associate Laboratory Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University Lisbon, Caparica, Portugal
- UCIBIO – Applied Molecular Biosciences Unit, NOVA School of Science and Technology, NOVA University of Lisbon, Caparica, Portugal
- MARE – Marine and Environmental Sciences Centre, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
- *Correspondence: Carolina Madeira, , orcid.org/0000-0003-1632-634X
| | - Marta Dias
- MARE – Marine and Environmental Sciences Centre, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
- Marta Dias, , orcid.org/0000-0003-0447-6009
| | - Ana Ferreira
- Biology Department, Oceanário de Lisboa, Lisbon, Portugal
| | - Raúl Gouveia
- Biology Department, Oceanário de Lisboa, Lisbon, Portugal
| | - Henrique Cabral
- MARE – Marine and Environmental Sciences Centre, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
- INRAE – National Research Institute for Agriculture, Food and Environment, UR EABX, Cestas, France
| | - Mário S. Diniz
- i4HB – Associate Laboratory Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University Lisbon, Caparica, Portugal
- UCIBIO – Applied Molecular Biosciences Unit, NOVA School of Science and Technology, NOVA University of Lisbon, Caparica, Portugal
| | - Catarina Vinagre
- MARE – Marine and Environmental Sciences Centre, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
- CCMAR – Centre of Marine Sciences, University of Algarve, Faro, Portugal
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8
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Hayashi K, Kuwamura T, Tachihara K, Reimer JD. Large host anemones can be shelters of a diverse assemblage of fish species, not just anemonefish. JOURNAL OF FISH BIOLOGY 2022; 100:40-50. [PMID: 34590316 DOI: 10.1111/jfb.14916] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 09/18/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
The mutualistic relationships between anemonefish (Amphiprion; Pomacentridae) and host sea anemones are well known, but host anemones are also used as shelter by damselfish (Pomacentridae), wrasses (Labridae) and cardinalfish (Apogonidae). The threespot dascyllus Dascyllus trimaculatus (Pomacentridae) is known to live on or near host anemones in their immature phase. Nonetheless, detailed studies on the use of host anemones by other fish species have not yet been conducted. To understand the factors that influence the use of host anemones by other fish species, this study investigated the fish biota around host anemones in the Ryukyu Archipelago. Other than Amphiprion spp. and D. trimaculatus, 10 additional species of fish (9 species of damselfish and 1 species of cardinalfish) were confirmed to temporarily use host anemones as shelter, and five species of wrasse including Labroides dimidiatus came to clean anemonefish. Logistic regression analyses (independent variable: presence or absence of other species of fish; dependent variables: anemonefish aggressiveness, size of host anemone, number of D. trimaculatus) indicated that the size of host anemones is important for the presence of fish, both in species using the anemone as temporary shelter and in cleaner species. Large host anemones can provide shelter and food resources for other species of coral reef fish as well as for anemonefish.
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Affiliation(s)
- Kina Hayashi
- Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Japan
| | - Tetsuo Kuwamura
- Faculty of Liberal Arts and Sciences, Chukyo University, Nagoya, Japan
| | - Katsunori Tachihara
- Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Japan
| | - James Davis Reimer
- Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Japan
- Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Japan
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9
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Bollati E, Rosenberg Y, Simon-Blecher N, Tamir R, Levy O, Huang D. Untangling the molecular basis of coral response to sedimentation. Mol Ecol 2021; 31:884-901. [PMID: 34738686 DOI: 10.1111/mec.16263] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 10/25/2021] [Accepted: 10/28/2021] [Indexed: 12/23/2022]
Abstract
Urbanized coral reefs are often chronically affected by sedimentation and reduced light levels, yet many species of corals appear to be able to thrive under these highly disturbed conditions. Recently, these marginal ecosystems have gained attention as potential climate change refugia due to the shading effect of suspended sediment, as well as potential reservoirs for stress-tolerant species. However, little research exists on the impact of sedimentation on coral physiology, particularly at the molecular level. Here, we investigated the transcriptomic response to sediment stress in corals of the family Merulinidae from a chronically turbid reef (one genet each of Goniastrea pectinata and Mycedium elephantotus from Singapore) and a clear-water reef (multiple genets of G. pectinata from the Gulf of Aqaba/Eilat). In two ex-situ experiments, we exposed corals to either natural sediment or artificial sediment enriched with organic matter and used whole-transcriptome sequencing (RNA sequencing) to quantify gene expression. Analysis revealed a shared basis for the coral transcriptomic response to sediment stress, which involves the expression of genes broadly related to energy metabolism and immune response. In particular, sediment exposure induced upregulation of anaerobic glycolysis and glyoxylate bypass enzymes, as well as genes involved in hydrogen sulphide metabolism and in pathogen pattern recognition. Our results point towards hypoxia as a probable driver of this transcriptomic response, providing a molecular basis to previous work that identified hypoxia as a primary cause of tissue necrosis in sediment-stressed corals. Potential metabolic and immunity trade-offs of corals living under chronic sedimentation should be considered in future studies on the ecology and conservation of turbid reefs.
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Affiliation(s)
- Elena Bollati
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,Department of Biology, Marine Biology Section, University of Copenhagen, Helsingør, Denmark
| | - Yaeli Rosenberg
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Noa Simon-Blecher
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Raz Tamir
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.,The Interuniversity Institute for Marine Sciences in Eilat, Eilat, Israel
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel.,The Interuniversity Institute for Marine Sciences in Eilat, Eilat, Israel
| | - Danwei Huang
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,Tropical Marine Science Institute, National University of Singapore, Singapore, Singapore.,Centre for Nature-based Climate Solutions, National University of Singapore, Singapore, Singapore
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10
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Ribas-Deulofeu L, Denis V, Château PA, Chen CA. Impacts of heat stress and storm events on the benthic communities of Kenting National Park (Taiwan). PeerJ 2021; 9:e11744. [PMID: 34386301 PMCID: PMC8312492 DOI: 10.7717/peerj.11744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 06/17/2021] [Indexed: 11/20/2022] Open
Abstract
Over the past few decades, extreme events—such as ocean warming, typhoons, and coral bleaching—have been increasing in intensity and frequency, threatening coral reefs from the physiological to ecosystem level. In the present study, the impacts of rising seawater temperatures, typhoons, and coral bleaching events on benthic communities were seasonally assessed over a 21 month-period, using photo-transects at 11 sites in Kenting National Park (KNP), Taiwan. Between August 2015 and April 2017, seven typhoon events were recorded and in situ seawater temperatures in KNP reached a maximum of 31.2 °C, as opposed to an average maximum SST of 28.8 °C (2007–2016). The state and response of benthic communities to these events were interpreted based on the environmental conditions of KNP. The repeated storms lowered the levels of thermal stress during the 2015–2016 El Niño event and may have mitigated its impact on the Taiwanese coral reefs. However, storm-induced local shifts from coral to macro-algae dominance were observed. Storms may mitigate the negative effects of heatwaves, but the mechanical damage induced by the storms may also decrease the structural complexity of reefs and their associated diversity. Eventually, despite reef persistence, the composition and function of remnant communities may profoundly diverge from those in regions with less active storms.
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Affiliation(s)
- Lauriane Ribas-Deulofeu
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.,Taiwan International Graduate Program-Biodiversity, Academia Sinica, Taipei, Taiwan.,Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Vianney Denis
- Institute of Oceanography, National Taiwan University, Taipei, Taiwan
| | - Pierre-Alexandre Château
- Department of Marine Environment and Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Chaolun Allen Chen
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.,Taiwan International Graduate Program-Biodiversity, Academia Sinica, Taipei, Taiwan.,Department of Life Science, National Taiwan Normal University, Taipei, Taiwan.,Department of Life Science, Tunghai University, Taichung, Taiwan
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11
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Takeuchi Y, Muraoka H, Yamakita T, Kano Y, Nagai S, Bunthang T, Costello MJ, Darnaedi D, Diway B, Ganyai T, Grudpan C, Hughes A, Ishii R, Lim PT, Ma K, Muslim AM, Nakano S, Nakaoka M, Nakashizuka T, Onuma M, Park C, Pungga RS, Saito Y, Shakya MM, Sulaiman MK, Sumi M, Thach P, Trisurat Y, Xu X, Yamano H, Yao TL, Kim E, Vergara S, Yahara T. The
Asia‐Pacific
Biodiversity Observation Network: 10‐year achievements and new strategies to 2030. Ecol Res 2021. [DOI: 10.1111/1440-1703.12212] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Yayoi Takeuchi
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies 16‐2 Onogawa, Tsukuba, Ibaraki 305‐8506 Japan
| | - Hiroyuki Muraoka
- River Basin Research Center Gifu University 1‐1 Yanagido, Gifu 501‐1193 Japan
| | - Takehisa Yamakita
- Marine Biodiversity and Environmental Assessment Research Center (BioEnv) Research Institute for Global Change (RIGC), Japan Agency for Marine‐Earth Science and Technology (JAMSTEC) 2‐15, Natsushima‐cho, Yokosuka Kanagawa 237‐0061 Japan
| | - Yuichi Kano
- Institute of Decision Science for a Sustainable Society, Kyushu University 744 Motooka Nishi‐ku, Fukuoka 819‐0395 Japan
| | - Shin Nagai
- Department of Environmental Geochemical Cycle Research Japan Agency for Marine‐Earth Science and Technology Yokohama Kanagawa 236‐0001 Japan
| | - Touch Bunthang
- Inland Fisheries Research and Development Institute of Fisheries Administration #186, Norodom Blvd., Phnom Penh Cambodia
| | - Mark John Costello
- Faculty of Bioscience and Aquaculture Nord Universitet Bodø Norway
- School of Environment University of Auckland Auckland 1142 New Zealand
| | - Dedy Darnaedi
- Universitas Nasional Jakarta Selatan Jakarta 12520 Indonesia
| | - Bibian Diway
- Research, Development and Innovation Division Forest Department Sarawak Kuching Sarawak Malaysia
| | - Tonny Ganyai
- Research and Development Department Sarawak Energy Berhad Kuching Sarawak Malaysia
| | - Chaiwut Grudpan
- Department of Fisheries Ubon Ratchathani University 85 Sathonlamak Rd, Mueang Si Khai, Warin Chamrap District, Ubon Ratchathani 34190 Thailand
| | - Alice Hughes
- Centre for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun Jinghong 666303 China
| | - Reiichiro Ishii
- Research Institute for Humanity and Nature 457‐4 Motoyama, Kamigamo, Kita‐ku, Kyoto 603‐8047 Japan
| | - Po Teen Lim
- Bachok Marine Research Station Institute of Ocean and Earth Sciences, University of Malaya Kelantan 16310 Malaysia
| | - Keping Ma
- State Key Laboratory of Vegetation and Environmental Change Institute of Botany, Chinese Academy of Sciences Xiangshan, Haidian District, Beijing 100093 China
| | - Aidy M. Muslim
- Institute of Oceanography and Environment (INOS), Universiti Malaysia Terengganu (UMT) Kuala Terengganu 21030 Malaysia
| | - Shin‐ichi Nakano
- Center for Ecological Research Kyoto University 2‐509‐3 Hirano, Otsu Shiga, 520‐2113 Japan
| | - Masahiro Nakaoka
- Akkeshi Marine Station, Field Science Center for Northern Biosphere Hokkaido University Aikappu 1 Akkeshi Hokkaido 088‐1113 Japan
| | - Tohru Nakashizuka
- Research Institute for Humanity and Nature 457‐4 Motoyama, Kamigamo, Kita‐ku, Kyoto 603‐8047 Japan
- Forestry and Forest Products Research Institute Tsukuba Ibaraki Japan
| | - Manabu Onuma
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies 16‐2 Onogawa, Tsukuba, Ibaraki 305‐8506 Japan
| | - Chan‐Ho Park
- Genetic Resources Information Center National Institute of Biological Resources 42 Hwangyeoung‐ro 42, Seo‐gu, Incheon, 22689 Republic of Korea
| | - Runi Sylvester Pungga
- Research, Development and Innovation Division Forest Department Sarawak Kuching Sarawak Malaysia
| | - Yusuke Saito
- Biodiversity Center of Japan, Ministry of the Environment, Japan Fujiyoshida City Yamanashi 403‐0005 Japan
| | | | | | - Maya Sumi
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies 16‐2 Onogawa, Tsukuba, Ibaraki 305‐8506 Japan
| | - Phanara Thach
- Inland Fisheries Research and Development Institute of Fisheries Administration #186, Norodom Blvd., Phnom Penh Cambodia
| | - Yongyut Trisurat
- Department of Forest Biology, Faculty of Forestry Kasetsart University Bangkok 10900 Thailand
| | - Xuehong Xu
- State Key Laboratory of Vegetation and Environmental Change Institute of Botany, Chinese Academy of Sciences, Biodiversity Committee, Chinese Academy of Sciences Beijing 100093 China
| | - Hiroya Yamano
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies 16‐2 Onogawa, Tsukuba, Ibaraki 305‐8506 Japan
| | - Tze Leong Yao
- Forest Research Institute Malaysia Kepong Selangor 52109 Malaysia
| | - Eun‐Shik Kim
- Department of Forestry, Environment, and Systems Kookmin University Seoul 02707 South Korea
| | - Sheila Vergara
- Biodiversity Information Management, ASEAN Centre for Biodiversity, Forestry Campus, UPLB Los Banos Laguna 4031 Philippines
| | - Tetsukazu Yahara
- Department of Biology Kyushu University Hakozaki 6‐10‐1, Higashi‐ku, Fukuoka 812‐81 Japan
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12
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Ares Á, Brisbin MM, Sato KN, Martín JP, Iinuma Y, Mitarai S. Extreme storms cause rapid but short-lived shifts in nearshore subtropical bacterial communities. Environ Microbiol 2021; 22:4571-4588. [PMID: 33448616 DOI: 10.1111/1462-2920.15178] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/27/2020] [Accepted: 07/24/2020] [Indexed: 01/04/2023]
Abstract
Climate change scenarios predict tropical cyclones will increase in both frequency and intensity, which will escalate the amount of terrestrial run-off and mechanical disruption affecting coastal ecosystems. Bacteria are key contributors to ecosystem functioning, but relatively little is known about how they respond to extreme storm events, particularly in nearshore subtropical regions. In this study, we combine field observations and mesocosm experiments to assess bacterial community dynamics and changes in physicochemical properties during early- and late-season tropical cyclones affecting Okinawa, Japan. Storms caused large and fast influxes of freshwater and terrestrial sediment - locally known as red soil pollution - and caused moderate increases of macronutrients, especially SiO2 and PO4 3-, with up to 25 and 0.5 μM respectively. We detected shifts in relative abundances of marine and terrestrially derived bacteria, including putative coral and human pathogens, during storm events. Soil input alone did not substantially affect marine bacterial communities in mesocosms, indicating that other components of run-off or other storm effects likely exert a larger influence on bacterial communities. The storm effects were short-lived and bacterial communities quickly recovered following both storm events. The early- and late-season storms caused different physicochemical and bacterial community changes, demonstrating the context-dependency of extreme storm responses in a subtropical coastal ecosystem.
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Affiliation(s)
- Ángela Ares
- Marine Biophysics Unit, Okinawa Institute of Science and Technology (OIST), Okinawa, Japan
| | - Margaret Mars Brisbin
- Marine Biophysics Unit, Okinawa Institute of Science and Technology (OIST), Okinawa, Japan
| | - Kirk N Sato
- Marine Biophysics Unit, Okinawa Institute of Science and Technology (OIST), Okinawa, Japan.,Friday Harbor Laboratories, University of Washington, WA, USA
| | - Juan P Martín
- Marine Biophysics Unit, Okinawa Institute of Science and Technology (OIST), Okinawa, Japan
| | - Yoshiteru Iinuma
- Instrumental Analysis Section, Okinawa Institute of Science and Technology (OIST), Okinawa, Japan
| | - Satoshi Mitarai
- Marine Biophysics Unit, Okinawa Institute of Science and Technology (OIST), Okinawa, Japan
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13
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Kitano YF, Hongo C, Yara Y, Sugihara K, Kumagai NH, Yamano H. Data on coral species occurrences in Japan since 1929. Ecol Res 2020. [DOI: 10.1111/1440-1703.12136] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Yuko F. Kitano
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies Ibaraki Japan
| | - Chuki Hongo
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies Ibaraki Japan
| | - Yumiko Yara
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies Ibaraki Japan
| | - Kaoru Sugihara
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies Ibaraki Japan
| | - Naoki H. Kumagai
- Center for Climate Change Adaptation National Institute for Environmental Studies Ibaraki Japan
| | - Hiroya Yamano
- Center for Environmental Biology and Ecosystem Studies National Institute for Environmental Studies Ibaraki Japan
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14
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Biondi P, Masucci GD, Reimer JD. Coral cover and rubble cryptofauna abundance and diversity at outplanted reefs in Okinawa, Japan. PeerJ 2020; 8:e9185. [PMID: 33024621 PMCID: PMC7518162 DOI: 10.7717/peerj.9185] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 04/23/2020] [Indexed: 11/20/2022] Open
Abstract
Global climate change is leading to damage and loss of coral reef ecosystems. On subtropical Okinawa Island in southwestern Japan, the prefectural government is working on coral reef restoration by outplanting coral colonies from family Acroporidae back to reefs after initially farming colonies inside protected nurseries. In order to establish a baseline for future comparisons, in this study we documented the current status of reefs undergoing outplanting at Okinawa Island, and nearby locations where no human manipulation has occurred. We examined three sites on the coast of Onna Village on the west coast of the island; each site included an outplanted and control location. We used (1) coral rubble sampling to measure and compare abundance and diversity of rubble cryptofauna; and (2) coral reef monitoring using Line Intercept Transects to track live coral coverage. Results showed that rubble shape had a positive correlation with the numbers of animals found within rubble themselves and may therefore constitute a reliable abundance predictor. Each outplanted location did not show differences with the corresponding control location in terms of rubble cryptofauna abundance, but outplanted locations had significantly lower coral coverage. Overall, differences between sites (Maeganeku1, Maeganeku2 and Manza, each including both outplanted and control locations) were significant, for both rubble cryptofauna and coral coverage. We recommend (1) to outplant colonies from more stress-resistant genera in place of Acropora, and (2) to conduct regular surveys to monitor the situation closely. With a lack of baseline data preceding impacts, rigorous monitoring over time can highlight trends towards increases or decreases in evaluated variables, allowing to obtain a clearer idea of the effects of transplants and on the trajectory of impacts due to climate change and local stressors . Finally, we also recommend (3) to establish conservation and sustainable practices that could aid the ongoing restoration efforts such as installing anchoring buoys to reduce impacts from anchoring, which could reduce coral mortality of both outplanted and native coral colonies.
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Affiliation(s)
- Piera Biondi
- Molecular Invertebrate Systematics and Ecology Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Giovanni Diego Masucci
- Molecular Invertebrate Systematics and Ecology Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - James Davis Reimer
- Molecular Invertebrate Systematics and Ecology Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa, Japan.,University of the Ryukyus, Tropical Biosphere Research Center, Okinawa, Japan
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15
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Sangmanee K, Casareto BE, Nguyen TD, Sangsawang L, Toyoda K, Suzuki T, Suzuki Y. Influence of thermal stress and bleaching on heterotrophic feeding of two scleractinian corals on pico-nanoplankton. MARINE POLLUTION BULLETIN 2020; 158:111405. [PMID: 32753190 DOI: 10.1016/j.marpolbul.2020.111405] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 06/22/2020] [Accepted: 06/23/2020] [Indexed: 06/11/2023]
Abstract
The feeding strategies of Montipora digitata and Porites lutea, two dominant corals in the Okinawan reefs, were investigated. The focus was on pico- and nanoplankton feeding efficiencies, using 6-h incubations. Although healthy M. digitata consumed from 72% to 87% more pico-nanoplankton cells than P. lutea, feeding rates of bleached corals of both species were similarly low at heat stress (33 °C). Heterotrophic carbon acquisition with respect to dark respiration varied from 3% to 65% in M. digitata and from 7% to 68% in P. lutea. A decrease in the feeding efficiency of bleached M. digitata under heat stress shows its vulnerability to water heating events. Feeding rates of P. lutea were low under all conditions and treatments; therefore, this species is less vulnerable to heat stress due to the strategy of meeting metabolic costs by using translocated organic matter from endoliths and selecting pico-nanoplankton cells with a high C/N ratio.
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Affiliation(s)
- Kanwara Sangmanee
- Environment and Energy Systems, Graduate Schools of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan; Marine Biodiversity Research Group, Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand
| | - Beatriz E Casareto
- Environment and Energy Systems, Graduate Schools of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan.
| | - The Duc Nguyen
- Environment and Energy Systems, Graduate Schools of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan; Institute of Marine Environment and Resources, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet St., Ha Noi, Viet Nam
| | - Laddawan Sangsawang
- Environment and Energy Systems, Graduate Schools of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan; Marine and Coastal Resources Research and Development Center, the Eastern Gulf of Thailand, Rayong Province 21170, Thailand
| | - Keita Toyoda
- Environment and Energy Systems, Graduate Schools of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan.
| | - Toshiyuki Suzuki
- Environment and Energy Systems, Graduate Schools of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan.
| | - Yoshimi Suzuki
- Environment and Energy Systems, Graduate Schools of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan.
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16
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Nanami A. Spatial distribution and feeding substrate of butterflyfishes (family Chaetodontidae) on an Okinawan coral reef. PeerJ 2020; 8:e9666. [PMID: 32832278 PMCID: PMC7413084 DOI: 10.7717/peerj.9666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 07/15/2020] [Indexed: 11/20/2022] Open
Abstract
Coral reefs support diverse communities, and relationships among organisms within these communities are quite complex. Among the relationships, clarifying the habitat association and foraging substrate selection relative to habitat characteristics is of central importance to ecology since these two aspects are the fundamentals for survival and growth of organisms. The aims of the present study were to investigate the spatial distribution and feeding substrate selection of 14 species of butterflyfishes on an Okinawan coral reef in Japan. Species-specific spatial distributions varied with habitat characteristics (e.g., encrusting corals, massive corals, branching Acropora and rock). For feeding substrates, seven species of obligate coral polyp feeders exhibited significant positive selectivity for tabular Acropora, corymbose Acropora, encrusting corals and massive corals but significant negative selectivity for dead corals, coral rubble and rock. Among six species of facultative coral polyp feeders, two species exhibited significant positive selectivity for encrusting corals and massive corals, and one species showed significant positive selectivity for dead corals as feeding substrates. In contrast, three species exhibited no significant positive selectivity for any feeding substrates. A similar result was observed for one non-coralline invertebrate feeder. Among the 14 species, 12 species showed a relatively close relationship between spatial distribution and feeding substrates but the remaining two species did not. The present study is the first study to elucidate species-specific spatial distributions and feeding substrate selection of butterflyfishes on an Okinawan coral reef. The results of the present study suggest that diverse substrates, including various types of living corals (especially encrusting corals, massive corals, tabular Acropora, corymbose Acropora and branching Acropora) and non-coralline substrates (rock) are the primary determinants of spatial distributions and feeding sites. Thus, diverse substrates are important for maintaining high species diversity of butterflyfishes and changes of the substrates would likely change the spatial patterns and foraging behavior, although species-specific responses may be found, depending on their species-specific dependence on vulnerable substrates.
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Affiliation(s)
- Atsushi Nanami
- Research Center for Sub-tropical Fisheries, Seikai National Fisheries Research Institute, Japan Fisheries Research and Education Agency, Ishigaki, Okinawa, Japan
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17
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DiBattista JD, Reimer JD, Stat M, Masucci GD, Biondi P, De Brauwer M, Wilkinson SP, Chariton AA, Bunce M. Environmental DNA can act as a biodiversity barometer of anthropogenic pressures in coastal ecosystems. Sci Rep 2020; 10:8365. [PMID: 32433472 PMCID: PMC7239923 DOI: 10.1038/s41598-020-64858-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 04/23/2020] [Indexed: 01/29/2023] Open
Abstract
Loss of biodiversity from lower to upper trophic levels reduces overall productivity and stability of coastal ecosystems in our oceans, but rarely are these changes documented across both time and space. The characterisation of environmental DNA (eDNA) from sediment and seawater using metabarcoding offers a powerful molecular lens to observe marine biota and provides a series of ‘snapshots’ across a broad spectrum of eukaryotic organisms. Using these next-generation tools and downstream analytical innovations including machine learning sequence assignment algorithms and co-occurrence network analyses, we examined how anthropogenic pressures may have impacted marine biodiversity on subtropical coral reefs in Okinawa, Japan. Based on 18 S ribosomal RNA, but not ITS2 sequence data due to inconsistent amplification for this marker, as well as proxies for anthropogenic disturbance, we show that eukaryotic richness at the family level significantly increases with medium and high levels of disturbance. This change in richness coincides with compositional changes, a decrease in connectedness among taxa, an increase in fragmentation of taxon co-occurrence networks, and a shift in indicator taxa. Taken together, these findings demonstrate the ability of eDNA to act as a barometer of disturbance and provide an exemplar of how biotic networks and coral reefs may be impacted by anthropogenic activities.
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Affiliation(s)
- Joseph D DiBattista
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Perth, WA, 6102, Australia. .,Australian Museum Research Institute, Australian Museum, 1 William St, Sydney, NSW, 2010, Australia.
| | - James D Reimer
- Molecular Invertebrate and Systematics Ecology Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 903-0213, Japan.,Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 903-0213, Japan
| | - Michael Stat
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Perth, WA, 6102, Australia.,School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Giovanni D Masucci
- Molecular Invertebrate and Systematics Ecology Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 903-0213, Japan
| | - Piera Biondi
- Molecular Invertebrate and Systematics Ecology Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 903-0213, Japan
| | - Maarten De Brauwer
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Perth, WA, 6102, Australia.,School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Shaun P Wilkinson
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Anthony A Chariton
- Department of Biological Sciences, Macquarie University, North Ryde, 2113, Australia
| | - Michael Bunce
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Perth, WA, 6102, Australia.,Environmental Protection Authority, 215 Lambton Quay, Wellington, 6011, New Zealand
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18
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Ng CSL, Huang D, Toh KB, Sam SQ, Kikuzawa YP, Toh TC, Taira D, Chan YKS, Hung LZT, Sim WT, Rashid AR, Afiq-Rosli L, Ng NK, Chou LM. Responses of urban reef corals during the 2016 mass bleaching event. MARINE POLLUTION BULLETIN 2020; 154:111111. [PMID: 32319927 DOI: 10.1016/j.marpolbul.2020.111111] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/25/2020] [Accepted: 03/25/2020] [Indexed: 05/28/2023]
Abstract
Predicting the bleaching responses of corals is crucial in light of frequent heat stress events to manage further losses of biodiversity and ecosystem functioning, especially for reefs impacted by urbanisation. We examined if the coral cover and community at various Singapore sites changed during the 2016 global coral bleaching event. Bleaching prevalence varied widely among sites in June 2016, and was best explained by site and coral species. While some sites were minimally impacted, others registered significant decreases in coral cover and community changes persisting till March 2017, when normal colouration was mostly regained by corals. Bleaching susceptibility was associated with larger corallites in hermaphrodites and smaller corallites in gonochores (probably due to the cost of maintaining dual sexual functions in hermaphrodites), and with increasing proximity between polyps (likely because thermal damage would be less contained among polyps with greater physiological integration). However, bleaching resilience-the capacity to regain baseline pigmentation-was poorly explained by the traits studied. Our findings suggest that the interplay between local conditions and species composition strongly affects bleaching outcomes on urbanised reefs, and underscore the utility of coral traits for predicting bleaching responses to help in formulating appropriate management strategies.
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Affiliation(s)
- Chin Soon Lionel Ng
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558; Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore.
| | - Danwei Huang
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558; Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
| | - Kok Ben Toh
- Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore; School of Natural Resources and Environment, University of Florida, 103 Black Hall, Gainsville, FL 32611, United States of America
| | - Shu Qin Sam
- Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
| | - Yuichi Preslie Kikuzawa
- Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
| | - Tai Chong Toh
- Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore; College of Alice and Peter Tan, National University of Singapore, 8 College Avenue East, 138615, Singapore
| | - Daisuke Taira
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558; Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
| | - Yong Kit Samuel Chan
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558
| | - Ling Zi Tracy Hung
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558
| | - Wan Ting Sim
- Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
| | - Ahmad Rafiuddin Rashid
- Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
| | - Lutfi Afiq-Rosli
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558; Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
| | - Ngan Kee Ng
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558
| | - Loke Ming Chou
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558; Tropical Marine Science Institute, National University of Singapore, 14 Kent Ridge Road, 119223, Singapore
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19
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Kim SW, Sampayo EM, Sommer B, Sims CA, Gómez-Cabrera MDC, Dalton SJ, Beger M, Malcolm HA, Ferrari R, Fraser N, Figueira WF, Smith SDA, Heron SF, Baird AH, Byrne M, Eakin CM, Edgar R, Hughes TP, Kyriacou N, Liu G, Matis PA, Skirving WJ, Pandolfi JM. Refugia under threat: Mass bleaching of coral assemblages in high-latitude eastern Australia. GLOBAL CHANGE BIOLOGY 2019; 25:3918-3931. [PMID: 31472029 DOI: 10.1111/gcb.14772] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/31/2019] [Accepted: 07/04/2019] [Indexed: 05/21/2023]
Abstract
Environmental anomalies that trigger adverse physiological responses and mortality are occurring with increasing frequency due to climate change. At species' range peripheries, environmental anomalies are particularly concerning because species often exist at their environmental tolerance limits and may not be able to migrate to escape unfavourable conditions. Here, we investigated the bleaching response and mortality of 14 coral genera across high-latitude eastern Australia during a global heat stress event in 2016. We evaluated whether the severity of assemblage-scale and genus-level bleaching responses was associated with cumulative heat stress and/or local environmental history, including long-term mean temperatures during the hottest month of each year (SSTLTMAX ), and annual fluctuations in water temperature (SSTVAR ) and solar irradiance (PARZVAR ). The most severely-bleached genera included species that were either endemic to the region (Pocillopora aliciae) or rare in the tropics (e.g. Porites heronensis). Pocillopora spp., in particular, showed high rates of immediate mortality. Bleaching severity of Pocillopora was high where SSTLTMAX was low or PARZVAR was high, whereas bleaching severity of Porites was directly associated with cumulative heat stress. While many tropical Acropora species are extremely vulnerable to bleaching, the Acropora species common at high latitudes, such as A. glauca and A. solitaryensis, showed little incidence of bleaching and immediate mortality. Two other regionally-abundant genera, Goniastrea and Turbinaria, were also largely unaffected by the thermal anomaly. The severity of assemblage-scale bleaching responses was poorly explained by the environmental parameters we examined. Instead, the severity of assemblage-scale bleaching was associated with local differences in species abundance and taxon-specific bleaching responses. The marked taxonomic disparity in bleaching severity, coupled with high mortality of high-latitude endemics, point to climate-driven simplification of assemblage structures and progressive homogenisation of reef functions at these high-latitude locations.
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Affiliation(s)
- Sun W Kim
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Eugenia M Sampayo
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Brigitte Sommer
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Carrie A Sims
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Maria Del C Gómez-Cabrera
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Steve J Dalton
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Maria Beger
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
- School of Biological Sciences, Centre for Biodiversity and Conservation Science, The University of Queensland, St. Lucia, QLD, Australia
| | - Hamish A Malcolm
- Fisheries Research, New South Wales Department of Primary Industries, Coffs Harbour, NSW, Australia
| | - Renata Ferrari
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
- Australian Institute of Marine Sciences, Townsville, QLD, Australia
| | - Nicola Fraser
- Solitary Islands Underwater Research Group, Coffs Harbour, NSW, Australia
| | - Will F Figueira
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Stephen D A Smith
- National Marine Science Centre, Southern Cross University, Coffs Harbour, NSW, Australia
| | - Scott F Heron
- Marine Geophysical Laboratory, Physics Department, College of Science and Engineering, James Cook University, Townsville, QLD, Australia
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
| | - Andrew H Baird
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
| | - Maria Byrne
- Anatomy and Histology, Bosch Institute, The University of Sydney, Sydney, NSW, Australia
| | - C Mark Eakin
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
| | - Robert Edgar
- Solitary Islands Underwater Research Group, Coffs Harbour, NSW, Australia
| | - Terry P Hughes
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
| | - Nicole Kyriacou
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Gang Liu
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
- Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USA
| | - Paloma A Matis
- School of Life Sciences, University of Technology Sydney, Broadway, NSW, Australia
| | - William J Skirving
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
| | - John M Pandolfi
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
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Repetitive sex change in the stony coral Herpolitha limax across a wide geographic range. Sci Rep 2019; 9:2936. [PMID: 30814532 PMCID: PMC6393666 DOI: 10.1038/s41598-018-37619-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 12/11/2018] [Indexed: 11/08/2022] Open
Abstract
Sex change has been widely studied in animals and plants. However, the conditions favoring sex change, its mode and timing remain poorly known. Here, for the first time in stony corals, we report on a protandrous (youngest individuals are males) repetitive sex change exhibited by the fungiid coral Herpolitha limax across large spatial scales (the coral reefs of Japan, Jordan and Israel) and temporal scales (2004-2017). In contrast to most corals, this species is a daytime spawner (08:00-10:00 AM) that spawned at the same time/same date across all the study sites. The sporadically scattered populations of H. limax among the coral reefs of Eilat (Israel) and Aqaba (Jordan) exhibited significantly slower growth, earlier sex change, and lower percentages of reproduction and sex change in comparison to the densely aggregated populations in Okinawa (Japan). At all sites, sex ratio varied among years, but was almost always biased towards maleness. Growth rate decreased with size. We conclude that comparable to dioecious plants that display labile sexuality in response to energetic and/or environmental constraints, the repetitive sex change displayed by H. limax increases its overall fitness reinforcing the important role of reproductive plasticity in the Phylum Cnidaria in determining their evolutionary success.
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21
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DiBattista JD, Reimer JD, Stat M, Masucci GD, Biondi P, De Brauwer M, Bunce M. Digging for DNA at depth: rapid universal metabarcoding surveys (RUMS) as a tool to detect coral reef biodiversity across a depth gradient. PeerJ 2019; 7:e6379. [PMID: 30755831 PMCID: PMC6368839 DOI: 10.7717/peerj.6379] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 12/24/2018] [Indexed: 11/20/2022] Open
Abstract
Background Effective biodiversity monitoring is fundamental in tracking changes in ecosystems as it relates to commercial, recreational, and conservation interests. Current approaches to survey coral reef ecosystems center on the use of indicator species and repeat surveying at specific sites. However, such approaches are often limited by the narrow snapshot of total marine biodiversity that they describe and are thus hindered in their ability to contribute to holistic ecosystem-based monitoring. In tandem, environmental DNA (eDNA) and next-generation sequencing metabarcoding methods provide a new opportunity to rapidly assess the presence of a broad spectrum of eukaryotic organisms within our oceans, ranging from microbes to macrofauna. Methods We here investigate the potential for rapid universal metabarcoding surveys (RUMS) of eDNA in sediment samples to provide snapshots of eukaryotic subtropical biodiversity along a depth gradient at two coral reefs in Okinawa, Japan based on 18S rRNA. Results Using 18S rRNA metabarcoding, we found that there were significant separations in eukaryotic community assemblages (at the family level) detected in sediments when compared across different depths ranging from 10 to 40 m (p = 0.001). Significant depth zonation was observed across operational taxonomic units assigned to the class Demospongiae (sponges), the most diverse class (contributing 81% of species) within the phylum Porifera; the oldest metazoan phylum on the planet. However, zonation was not observed across the class Anthozoa (i.e., anemones, stony corals, soft corals, and octocorals), suggesting that the former may serve as a better source of indicator species based on sampling over fine spatial scales and using this universal assay. Furthermore, despite their abundance on the examined coral reefs, we did not detect any octocoral DNA, which may be due to low cellular shedding rates, assay sensitivities, or primer biases. Discussion Overall, our pilot study demonstrates the importance of exploring depth effects in eDNA and suggest that RUMS may be applied to provide a baseline of information on eukaryotic marine taxa at coastal sites of economic and conservation importance.
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Affiliation(s)
- Joseph D DiBattista
- Trace and Environmental DNA (TrEnD) laboratory, School of Molecular and Life Sciences, Curtin University of Technology, Perth, WA, Australia.,Australian Museum Research Institute, Australian Museum, Sydney, NSW, Australia
| | - James D Reimer
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan.,Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | - Michael Stat
- Trace and Environmental DNA (TrEnD) laboratory, School of Molecular and Life Sciences, Curtin University of Technology, Perth, WA, Australia.,Department of Biological Sciences, Macquarie University, North Ryde, NSW, Australia
| | - Giovanni D Masucci
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan
| | - Piera Biondi
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan
| | - Maarten De Brauwer
- Trace and Environmental DNA (TrEnD) laboratory, School of Molecular and Life Sciences, Curtin University of Technology, Perth, WA, Australia
| | - Michael Bunce
- Trace and Environmental DNA (TrEnD) laboratory, School of Molecular and Life Sciences, Curtin University of Technology, Perth, WA, Australia
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22
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Nakajima Y, Chuang PS, Ueda N, Mitarai S. First evidence of asexual recruitment of Pocillopora acuta in Okinawa Island using genotypic identification. PeerJ 2018; 6:e5915. [PMID: 30473933 PMCID: PMC6237110 DOI: 10.7717/peerj.5915] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/10/2018] [Indexed: 11/20/2022] Open
Abstract
Okinawa Island is located near the center of the Nansei Islands (∼24–31°N), at a relatively high latitude for coral reefs. Nevertheless, more than 80 coral genera (over 400 species) are abundant in the Nansei Islands. Since March, 2017, scleractinian corals have been held in an outdoor tank at the OIST Marine Science Station at Seragaki, Onna with natural sea water flow-through in order to be used in molecular biological and physiological studies. In January, 2018, we found small pocilloporid-like colonies suspected to have originated asexually. We collected 25 small colonies and measured their sizes and weights. Also, we validated the classification and clonality of the colonies using a mitochondrial locus and nine microsatellite loci. Almost all of the small colonies collected in the outdoor tank were ≤1 cm in both width and height. The weight of dried skeletons ranged from 0.0287 to 0.1807 g. Genetic analysis determined that they were, in fact, Pocillopora acuta. Only one mitochondrial haplotype was shared and two microsatellite multilocus genotypes were detected (20 colonies of one and four colonies of the other). The mitochondrial haplotype and one microsatellite multilocus genotype for 20 colonies corresponded to those of one P. acuta colony being kept in the tank. One small colony matched both multilocus genotypes. This may have been a chimeric colony resulting from allogenic fusion. These small colonies were not produced sexually, because the only potential parent in the tank was the aforementioned P. acuta colony. Instead, they were more likely derived from asexual planula release or polyp bail-out. Corals as Pocillopora acuta have the capacity to produce clonal offspring rapidly and to adapt readily to local environments. This is the first report of asexual reproduction by planulae or expelled polyps in P. acuta at Okinawa Island.
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Affiliation(s)
- Yuichi Nakajima
- Marine Biophysics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Po-Shun Chuang
- Marine Biophysics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Nobuo Ueda
- Okinawa Marine Science Support Section, OIST Marine Science Station, Onna, Okinawa, Japan
| | - Satoshi Mitarai
- Marine Biophysics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
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23
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Lam VYY, Chaloupka M, Thompson A, Doropoulos C, Mumby PJ. Acute drivers influence recent inshore Great Barrier Reef dynamics. Proc Biol Sci 2018; 285:rspb.2018.2063. [PMID: 30404884 DOI: 10.1098/rspb.2018.2063] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 10/12/2018] [Indexed: 11/12/2022] Open
Abstract
Understanding the dynamics of habitat-forming organisms is fundamental to managing natural ecosystems. Most studies of coral reef dynamics have focused on clear-water systems though corals inhabit many turbid regions. Here, we illustrate the key drivers of an inshore coral reef ecosystem using 10 years of biological, environmental, and disturbance data. Tropical cyclones, crown-of-thorns starfish, and coral bleaching are recognized as the major drivers of coral loss at mid- and offshore reefs along the Great Barrier Reef (GBR). In comparison, little is known about what drives temporal trends at inshore reefs closer to major anthropogenic stress. We assessed coral cover dynamics using state-space models within six major inshore GBR catchments. An overall decline was detected in nearly half (46%) of the 15 reefs at two depths (30 sites), while the rest exhibited fluctuating (23%), static (17%), or positive (13%) trends. Inshore reefs responded similarly to their offshore counterparts, where contemporary trends were predominantly influenced by acute disturbance events. Storms emerged as the major driver affecting the inshore GBR, with the effects of other drivers such as disease, juvenile coral density, and macroalgal and turf per cent cover varying from one catchment to another. Flooding was also associated with negative trends in live coral cover in two southern catchments, but the mechanism remains unclear as it is not reflected in available metrics of water quality and may act through indirect pathways.
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Affiliation(s)
- Vivian Y Y Lam
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia .,Australian Research Council Centre of Excellence for Coral Reef Studies, St. Lucia, Queensland, Australia
| | - Milani Chaloupka
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia.,Ecological Modelling Services Pty Ltd, The University of Queensland, Queensland, Australia
| | - Angus Thompson
- Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Christopher Doropoulos
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia.,CSIRO Oceans and Atmosphere, St. Lucia, Queensland, Australia
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia .,Australian Research Council Centre of Excellence for Coral Reef Studies, St. Lucia, Queensland, Australia
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24
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Heery EC, Hoeksema BW, Browne NK, Reimer JD, Ang PO, Huang D, Friess DA, Chou LM, Loke LHL, Saksena-Taylor P, Alsagoff N, Yeemin T, Sutthacheep M, Vo ST, Bos AR, Gumanao GS, Syed Hussein MA, Waheed Z, Lane DJW, Johan O, Kunzmann A, Jompa J, Taira D, Bauman AG, Todd PA. Urban coral reefs: Degradation and resilience of hard coral assemblages in coastal cities of East and Southeast Asia. MARINE POLLUTION BULLETIN 2018; 135:654-681. [PMID: 30301085 DOI: 10.1016/j.marpolbul.2018.07.041] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 07/10/2018] [Accepted: 07/16/2018] [Indexed: 05/28/2023]
Abstract
Given predicted increases in urbanization in tropical and subtropical regions, understanding the processes shaping urban coral reefs may be essential for anticipating future conservation challenges. We used a case study approach to identify unifying patterns of urban coral reefs and clarify the effects of urbanization on hard coral assemblages. Data were compiled from 11 cities throughout East and Southeast Asia, with particular focus on Singapore, Jakarta, Hong Kong, and Naha (Okinawa). Our review highlights several key characteristics of urban coral reefs, including "reef compression" (a decline in bathymetric range with increasing turbidity and decreasing water clarity over time and relative to shore), dominance by domed coral growth forms and low reef complexity, variable city-specific inshore-offshore gradients, early declines in coral cover with recent fluctuating periods of acute impacts and rapid recovery, and colonization of urban infrastructure by hard corals. We present hypotheses for urban reef community dynamics and discuss potential of ecological engineering for corals in urban areas.
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Affiliation(s)
- Eliza C Heery
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Bert W Hoeksema
- Taxonomy and Systematics Group, Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, the Netherlands; Institute of Biology Leiden, Leiden University, P.O. Box 9505, 2300 RA Leiden, the Netherlands.
| | - Nicola K Browne
- Molecular and Life Sciences, Faculty of Science and Engineering, Bentley Campus, Curtin University, Perth, WA 6102, Australia; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - James D Reimer
- Molecular Invertebrate Systematics and Ecology Laboratory, Department of Biology, Chemistry and Marine Sciences, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, Japan; Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Put O Ang
- Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Danwei Huang
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore; Tropical Marine Science Institute, National University of Singapore, Singapore 119227, Singapore
| | - Daniel A Friess
- Department of Geography, National University of Singapore, Singapore 117570, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Loke Ming Chou
- Tropical Marine Science Institute, National University of Singapore, Singapore 119227, Singapore
| | - Lynette H L Loke
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Poonam Saksena-Taylor
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Nadia Alsagoff
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Thamasak Yeemin
- Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University, Huamark, Bangkok 10240, Thailand
| | - Makamas Sutthacheep
- Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University, Huamark, Bangkok 10240, Thailand
| | - Si Tuan Vo
- Institute of Oceanography, Vietnam Academy of Science and Technology, 1 Cau Da, Nha Trang, Khanh Hoa, Viet Nam
| | - Arthur R Bos
- Department of Biology, The American University in Cairo, P.O. Box 74, New Cairo 11835, Egypt; Taxonomy and Systematics Group, Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, the Netherlands
| | - Girley S Gumanao
- Marine Biology Department, Davao del Norte State College, New Visayas, 8105 Panabo City, the Philippines
| | - Muhammad Ali Syed Hussein
- Endangered Marine Species Research Unit, Borneo Marine Research Institute, Universiti Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia
| | - Zarinah Waheed
- Endangered Marine Species Research Unit, Borneo Marine Research Institute, Universiti Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia
| | - David J W Lane
- Lee Kong Chian Natural History Museum, Faculty of Science, National University of Singapore, 2 Conservatory Drive, Singapore 117377, Singapore
| | - Ofri Johan
- Research Institute for Ornamental Fish Culture, Jl. Perikanan No. 13, Pancoran Mas, Kota Depok, Jawa Barat 16436, Indonesia
| | - Andreas Kunzmann
- Leibniz Center for Tropical Marine Research (ZMT), Fahrenheitstr. 6, 28359 Bremen, Germany
| | - Jamaluddin Jompa
- Department of Marine Science, Hasanuddin University, Makassar, Indonesia
| | - Daisuke Taira
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Andrew G Bauman
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Peter A Todd
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore.
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Zayasu Y, Satoh N, Shinzato C. Genetic diversity of farmed and wild populations of the reef-building coral, Acropora tenuis. Restor Ecol 2018. [DOI: 10.1111/rec.12687] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Yuna Zayasu
- Marine Genomics Unit; Okinawa Institute of Science and Technology Graduate University; 1919-1 Tancha, Onna-son, Okinawa, 904-0495 Japan
| | - Noriyuki Satoh
- Marine Genomics Unit; Okinawa Institute of Science and Technology Graduate University; 1919-1 Tancha, Onna-son, Okinawa, 904-0495 Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute; The University of Tokyo; Chiba, 277-8564 Japan
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26
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Kumagai NH, Yamano H. High-resolution modeling of thermal thresholds and environmental influences on coral bleaching for local and regional reef management. PeerJ 2018; 6:e4382. [PMID: 29473007 PMCID: PMC5817939 DOI: 10.7717/peerj.4382] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 01/29/2018] [Indexed: 11/28/2022] Open
Abstract
Coral reefs are one of the world's most threatened ecosystems, with global and local stressors contributing to their decline. Excessive sea-surface temperatures (SSTs) can cause coral bleaching, resulting in coral death and decreases in coral cover. A SST threshold of 1 °C over the climatological maximum is widely used to predict coral bleaching. In this study, we refined thermal indices predicting coral bleaching at high-spatial resolution (1 km) by statistically optimizing thermal thresholds, as well as considering other environmental influences on bleaching such as ultraviolet (UV) radiation, water turbidity, and cooling effects. We used a coral bleaching dataset derived from the web-based monitoring system Sango Map Project, at scales appropriate for the local and regional conservation of Japanese coral reefs. We recorded coral bleaching events in the years 2004-2016 in Japan. We revealed the influence of multiple factors on the ability to predict coral bleaching, including selection of thermal indices, statistical optimization of thermal thresholds, quantification of multiple environmental influences, and use of multiple modeling methods (generalized linear models and random forests). After optimization, differences in predictive ability among thermal indices were negligible. Thermal index, UV radiation, water turbidity, and cooling effects were important predictors of the occurrence of coral bleaching. Predictions based on the best model revealed that coral reefs in Japan have experienced recent and widespread bleaching. A practical method to reduce bleaching frequency by screening UV radiation was also demonstrated in this paper.
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Affiliation(s)
- Naoki H. Kumagai
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
| | - Hiroya Yamano
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
| | - Committee Sango-Map-Project
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
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27
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Zayasu Y, Nakajima Y, Sakai K, Suzuki G, Satoh N, Shinzato C. Unexpectedly complex gradation of coral population structure in the Nansei Islands, Japan. Ecol Evol 2016; 6:5491-505. [PMID: 27551399 PMCID: PMC4984520 DOI: 10.1002/ece3.2296] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/08/2016] [Accepted: 06/10/2016] [Indexed: 12/11/2022] Open
Abstract
To establish effective locations and sizes of potential protected areas for reef ecosystems, detailed information about source and sink relationships between populations is critical, especially in archipelagic regions. Therefore, we assessed population structure and genetic diversity of Acropora tenuis, one of the dominant stony coral species in the Pacific, using 13 microsatellite markers to investigate 298 colonies from 15 locations across the Nansei Islands in southwestern Japan. Genetic diversity was not significant among sampling locations, even in possibly peripheral locations. In addition, our results showed that there are at least two populations of A. tenuis in the study area. The level of genetic differentiation between these populations was relatively low, but significant between many pairs of sampling locations. Directions of gene flow, which were estimated using a coalescence-based approach, suggest that gene flow not only occurs from south to north, but also from north to south in various locations. Consequently, the Yaeyama Islands and the Amami Islands are potential northern and southern sources of corals. On the other hand, the Miyako Islands and west central Okinawa Island are potential sink populations. The Kerama Islands and the vicinity of Taketomi Island are potential contact points of genetic subdivision of coral populations in the Nansei Islands. We found that genetic population structure of A. tenuis in the Nansei Islands is more complex than previously thought. These cryptic populations are very important for preserving genetic diversity and should be maintained.
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Affiliation(s)
- Yuna Zayasu
- Marine Genomics UnitOkinawa Institute of Science and Technology Graduate University1919‐1 TanchaOnna‐sonOkinawa904‐0405Japan
| | - Yuichi Nakajima
- Marine Biophysics UnitOkinawa Institute of Science and Technology Graduate University1919‐1 TanchaOnna‐sonOkinawa904‐0405Japan
| | - Kazuhiko Sakai
- Sesoko StationUniversity of the Ryukyus3422 SesokoMotobuOkinawa905‐0227Japan
| | - Go Suzuki
- Ishigaki Tropical StationSeikai National Fisheries Research InstituteFisheries Research Agency148‐446 Fukai‐otaIshigakiOkinawa907‐0451Japan
| | - Noriyuki Satoh
- Marine Genomics UnitOkinawa Institute of Science and Technology Graduate University1919‐1 TanchaOnna‐sonOkinawa904‐0405Japan
| | - Chuya Shinzato
- Marine Genomics UnitOkinawa Institute of Science and Technology Graduate University1919‐1 TanchaOnna‐sonOkinawa904‐0405Japan
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28
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Coupling Remote Sensing and Coral Annual Band Data to Investigate the History of Catchment Land Use and Coral Reef Status. ACTA ACUST UNITED AC 2016. [DOI: 10.1007/978-4-431-54364-0_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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29
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Renema W, Pandolfi JM, Kiessling W, Bosellini FR, Klaus JS, Korpanty C, Rosen BR, Santodomingo N, Wallace CC, Webster JM, Johnson KG. Are coral reefs victims of their own past success? SCIENCE ADVANCES 2016; 2:e1500850. [PMID: 27152330 PMCID: PMC4846430 DOI: 10.1126/sciadv.1500850] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 03/28/2016] [Indexed: 05/26/2023]
Abstract
As one of the most prolific and widespread reef builders, the staghorn coral Acropora holds a disproportionately large role in how coral reefs will respond to accelerating anthropogenic change. We show that although Acropora has a diverse history extended over the past 50 million years, it was not a dominant reef builder until the onset of high-amplitude glacioeustatic sea-level fluctuations 1.8 million years ago. High growth rates and propagation by fragmentation have favored staghorn corals since this time. In contrast, staghorn corals are among the most vulnerable corals to anthropogenic stressors, with marked global loss of abundance worldwide. The continued decline in staghorn coral abundance and the mounting challenges from both local stress and climate change will limit the coral reefs' ability to provide ecosystem services.
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Affiliation(s)
- Willem Renema
- Naturalis Biodiversity Center, PO Box 9517, 2300RA Leiden, Netherlands
| | - John M. Pandolfi
- School of Biological Sciences, ARC Centre of Excellence for Coral Reef Studies, University of Queensland, Brisbane, Queensland QLD 4072, Australia
| | - Wolfgang Kiessling
- GeoZentrum Nordbayern, Section Palaeoenvironmental Research, Universität Erlangen, Loewenichstrasse 28, 91054 Erlangen, Germany
| | - Francesca R. Bosellini
- Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - James S. Klaus
- Department of Geological Sciences, University of Miami, 43 Cox Science, Coral Gables, FL 33124–0401, USA
| | - Chelsea Korpanty
- School of Biological Sciences, ARC Centre of Excellence for Coral Reef Studies, University of Queensland, Brisbane, Queensland QLD 4072, Australia
| | - Brian R. Rosen
- Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | | | - Carden C. Wallace
- Biodiversity and Geosciences Program, Queensland Museum, Brisbane, Queensland 4101, Australia
| | - Jody M. Webster
- Geocoastal Research Group, School of Geosciences, The University of Sydney, Madsen Building F09, Sydney, New South Wales 2006, Australia
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Genome-wide SNP analysis explains coral diversity and recovery in the Ryukyu Archipelago. Sci Rep 2015; 5:18211. [PMID: 26656261 PMCID: PMC4674749 DOI: 10.1038/srep18211] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 11/12/2015] [Indexed: 01/16/2023] Open
Abstract
Following a global coral bleaching event in 1998, Acropora corals surrounding most of Okinawa island (OI) were devastated, although they are now gradually recovering. In contrast, the Kerama Islands (KIs) only 30 km west of OI, have continuously hosted a great variety of healthy corals. Taking advantage of the decoded Acropora digitifera genome and using genome-wide SNP analyses, we clarified Acropora population structure in the southern Ryukyu Archipelago (sRA). Despite small genetic distances, we identified distinct clusters corresponding to specific island groups, suggesting infrequent long-distance dispersal within the sRA. Although the KIs were believed to supply coral larvae to OI, admixture analyses showed that such dispersal is much more limited than previously realized, indicating independent recovery of OI coral populations and the necessity of local conservation efforts for each region. We detected strong historical migration from the Yaeyama Islands (YIs) to OI, and suggest that the YIs are the original source of OI corals. In addition, migration edges to the KIs suggest that they are a historical sink population in the sRA, resulting in high diversity. This population genomics study provides the highest resolution data to date regarding coral population structure and history.
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The effect of filamentous turf algal removal on the development of gametes of the coral Orbicella annularis. PLoS One 2015; 10:e0117936. [PMID: 25658586 PMCID: PMC4320090 DOI: 10.1371/journal.pone.0117936] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/05/2015] [Indexed: 11/19/2022] Open
Abstract
Macroalgae and filamentous turf algae (FTA) are abundant on degraded coral reefs, and the reproductive responses of corals may indicate sub-lethal stress under these conditions. The percentage of gametogenic stages (PGS) and the maximum diameter of eggs (MDE; or egg size) of Orbicella annularis were used to evaluate the effect of long- (7–10 months) and short-term (2.5 months) FTA removal (treatments T1 and T2, respectively) at both the beginning (May) and the end (August) of gametogenesis. Ramets (individual lobes of a colony) surrounded by FTA (T3) or crustose coralline algae (CCA; T4) were used as controls. The removal of FTA enhanced the development of gametes (i.e., a larger and higher percentage of mature gametes (PMG)) of O. annularis for T1 vs. T3 ramets in May and T1 and T2 vs. T3 ramets in August. Similar values of PGS and MDE between gametes from T3 and T4 in both May and August were unexpected because a previous study had shown that the same ramets of T4 (with higher tissue thickness, chlorophyll a cm-2 and zooxanthellae density and lower mitotic index values) were less stressed than ramets of T3. Evaluating coral stress through reproduction can reveal more sensitive responses than other biological parameters; within reproductive metrics, PGS can be a better stress indicator than egg size. The presence of turf algae strongly impacted the development of gametes and egg size (e.g., PMG in ramets with FTA removal increased almost twofold in comparison with ramets surrounded by FTA in August), most likely exerting negative chronic effects in the long run due to the ubiquity and permanence of turf algae in the Caribbean. These algae can be considered a stressor that affects coral sexual reproduction. Although the effects of turf algae on O. annularis are apparently less severe than those of other stressors, the future of this species is uncertain because of the combined impacts of these effects, the decline of O. annularis populations and the almost complete lack of recruitment.
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