1
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Lachs L. Ecosystem restoration: Healing blasts from the past. Curr Biol 2024; 34:R254-R256. [PMID: 38531321 DOI: 10.1016/j.cub.2024.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Blast fishing reduces coral reefs to fields of rubble. A new study of a project to restore blast-fished reefs reveals rapid recovery of reef carbonate budgets and reef health but highlights that further work is needed to restore coral biodiversity.
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Affiliation(s)
- Liam Lachs
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK.
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2
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Lange ID, Razak TB, Perry CT, Maulana PB, Prasetya ME, Irwan, Lamont TA. Coral restoration can drive rapid reef carbonate budget recovery. Curr Biol 2024; 34:1341-1348.e3. [PMID: 38460511 DOI: 10.1016/j.cub.2024.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/05/2023] [Accepted: 02/06/2024] [Indexed: 03/11/2024]
Abstract
Restoration is increasingly seen as a necessary tool to reverse ecological decline across terrestrial and marine ecosystems.1,2 Considering the unprecedented loss of coral cover and associated reef ecosystem services, active coral restoration is gaining traction in local management strategies and has recently seen major increases in scale. However, the extent to which coral restoration may restore key reef functions is poorly understood.3,4 Carbonate budgets, defined as the balance between calcium carbonate production and erosion, influence a reef's ability to provide important geo-ecological functions including structural complexity, reef framework production, and vertical accretion.5 Here we present the first assessment of reef carbonate budget trajectories at restoration sites. The study was conducted at one of the world's largest coral restoration programs, which transplants healthy coral fragments onto hexagonal metal frames to consolidate degraded rubble fields.6 Within 4 years, fast coral growth supports a rapid recovery of coral cover (from 17% ± 2% to 56% ± 4%), substrate rugosity (from 1.3 ± 0.1 to 1.7 ± 0.1) and carbonate production (from 7.2 ± 1.6 to 20.7 ± 2.2 kg m-2 yr-1). Four years after coral transplantation, net carbonate budgets have tripled and are indistinguishable from healthy control sites (19.1 ± 3.1 and 18.7 ± 2.2 kg m-2 yr-1, respectively). However, taxa-level contributions to carbonate production differ between restored and healthy reefs due to the preferential use of branching corals for transplantation. While longer observation times are necessary to observe any self-organization ability of restored reefs (natural recruitment, resilience to thermal stress), we demonstrate the potential of large-scale, well-managed coral restoration projects to recover important ecosystem functions within only 4 years.
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Affiliation(s)
- Ines D Lange
- Faculty of Environment, Science and Economy, University of Exeter, Exeter EX4 4RJ, UK.
| | - Tries B Razak
- Research Centre for Oceanography, National Research and Innovation Agency (BRIN), Jakarta Pusat 10340, Indonesia; School of Coral Reef Restoration (SCORES), Faculty of Fisheries and Marine Science, IPB University, Bogor 16680, Indonesia
| | - Chris T Perry
- Faculty of Environment, Science and Economy, University of Exeter, Exeter EX4 4RJ, UK
| | | | | | - Irwan
- Mars Sustainable Solutions, Makassar 90224, Indonesia
| | - Timothy Ac Lamont
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YW, UK
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3
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Horoszowski-Fridman YB, Izhaki I, Katz SM, Barkan R, Rinkevich B. Shifting reef restoration focus from coral survivorship to biodiversity using Reef Carpets. Commun Biol 2024; 7:141. [PMID: 38297065 PMCID: PMC10830465 DOI: 10.1038/s42003-024-05831-4] [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: 05/31/2023] [Accepted: 01/18/2024] [Indexed: 02/02/2024] Open
Abstract
To enhance the practice of farmed-coral transplantation, we conducted a trial of an approach called "Reef Carpets" (RC), which draws inspiration from the commercial turf-grass sod in land-based lawn gardening. Three 8.4m2 RCs were established on a sandy seabed, containing preselected combinations of branching corals (Acropora cf. variabilis, Pocillopora damicornis, Stylophora pistillata) with nursery recruited dwellers, and were monitored for 17-months. Corals within RCs grew, supported coral recruitment and offered ecological habitats for coral-associated organisms. While the unstable sediment underneath the RCs increased corals' partial mortalities, corals managed to grow and propagate. The extent of fish and gastropods corallivory varied among the coral species and planulation of Stylophora transplants was significantly higher than same-size natal-colonies. The RCs provided conducive environments for fish/invertebrate communities (183 taxa), and each coral species influenced specifically species-diversity and reef-associated communities. Even dead corals played crucial roles as habitats for reef biota, sustaining >80% of the RCs diversity; hence, they should not be considered automatically as indicators of failure. RCs scaled-up reef restoration and generated, in short periods, new reefs in denuded zones with enhanced biodiversity. Yet, RCs employment on soft-beds could be improved by using more structured artificial frameworks, requiring further research efforts.
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Affiliation(s)
- Yael B Horoszowski-Fridman
- Israel Oceanographic and Limnological Research, Tel-Shikmona, Haifa, 31080, Israel
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 31905, Israel
| | - Ido Izhaki
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 31905, Israel
| | - Sefano M Katz
- The School of Marine Sciences, Ruppin Academic Center, Michmoret, 40297, Israel
- Pacific Blue Foundation, PO Box 13306, Suva, Fiji Islands
| | - Ronen Barkan
- The School of Marine Sciences, Ruppin Academic Center, Michmoret, 40297, Israel
| | - Baruch Rinkevich
- Israel Oceanographic and Limnological Research, Tel-Shikmona, Haifa, 31080, Israel.
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4
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Leung SK, Mumby PJ. Mapping the susceptibility of reefs to rubble accumulation across the Great Barrier Reef. ENVIRONMENTAL MONITORING AND ASSESSMENT 2024; 196:211. [PMID: 38285268 PMCID: PMC10824869 DOI: 10.1007/s10661-024-12344-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 01/09/2024] [Indexed: 01/30/2024]
Abstract
Disturbance-induced rubble accumulations are described as "killing fields" on coral reefs as coral recruits suffer high post-settlement mortality, creating a bottleneck for reef recovery. The increasing frequency of coral bleaching events, that can generate rubble once coral dies, has heightened concerns that rubble beds will become more widespread and persistent. But we currently lack the tools to predict where rubble is most likely to accumulate. Here, we developed a modelling framework to identify areas that are likely to accumulate rubble on forereef slopes across the Great Barrier Reef. The algorithm uses new high-resolution bathymetric and geomorphic datasets from satellite remote sensing. We found that 47 km of reef slope (3% of the entire reef surveyed), primarily in the southern region, could potentially reach 50% rubble cover. Despite being statistically significant (p < 0.001), the effects of depth and aspect on rubble cover were minimal, with a 0.2% difference in rubble cover between deeper and shallower regions, as well as a maximum difference of 0.8% among slopes facing various directions. Therefore, we conclude that the effects of depth and aspect were insufficient to influence ecological processes such as larval recruitment and recovery in different coral communities. Maps of potential rubble accumulation can be used to prioritise surveys and potential restoration, particularly after major disturbances have occurred.
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Affiliation(s)
- Shu Kiu Leung
- Marine Spatial Ecology Lab, School of the Environment, University of Queensland, Level 5, Goddard Building, St. Lucia, QLD, Brisbane, 4072, Australia.
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of the Environment, University of Queensland, Level 5, Goddard Building, St. Lucia, QLD, Brisbane, 4072, Australia
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5
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Hadi TA, Utama RS, Arfianti T. Species richness and the dynamics of coral cover in Bangka Belitung Islands, Indonesia. PeerJ 2023; 11:e14625. [PMID: 36860768 PMCID: PMC9969856 DOI: 10.7717/peerj.14625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 12/02/2022] [Indexed: 03/03/2023] Open
Abstract
Pressures on the world's tropical coral reefs that threaten their existence have been reported worldwide due to many stressors. Loss of coral cover and declines in coral richness are two of the most common changes often reported in coral reefs. However, a precise estimate of species richness and the coral cover dynamics for most Indonesian regions, particularly in the Bangka Belitung Islands, have been poorly documented. Annual monitoring data from 2015 to 2018 at 11 fixed sites in the Bangka Belitung Islands using the photo quadrat transect method identified 342 coral species from 63 genera. Of these, 231 species (>65%) were rare or uncommon, occurring in <40% of all sites. The species richness of hard corals was categorized as moderate compared to other studies in Indonesia, averaging 53 species across sites and years, and there was an increasing number of sites with high species richness. The percent cover of live and dead hard corals was greater than other benthic and substrate categories in all sites; revealing a live-dead hard corals pattern with dead coral cover averaged 12% higher than live hard coral across the years, but they did not show a significant difference (P > 0.05). There was a slightly increasing trend in hard coral cover in ten out of 11 sites in 2018, indicating the reefs are in a recovery process. The results support the need to identify recovering or stable areas despite apparent anthropogenic and natural variations recently. This vital information is essential for early detection and preparation for management strategies in the current context of climate change and for ensuring future coral reef survival.
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Affiliation(s)
- Tri Aryono Hadi
- Research Center for Oceanography - National Research and Innovation Agency, North Jakarta, Jakarta, Indonesia
| | - Rizkie Satriya Utama
- Research Center for Oceanography - National Research and Innovation Agency, North Jakarta, Jakarta, Indonesia
| | - Tri Arfianti
- Research Center for Biosystematics and Evolution - National Research and Innovation Agency, Cibinong, West Java, Indonesia
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6
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Mezger SD, Klinke A, Tilstra A, El-Khaled YC, Thobor B, Wild C. The widely distributed soft coral Xenia umbellata exhibits high resistance against phosphate enrichment and temperature increase. Sci Rep 2022; 12:22135. [PMID: 36550166 PMCID: PMC9780247 DOI: 10.1038/s41598-022-26325-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
Both global and local factors affect coral reefs worldwide, sometimes simultaneously. An interplay of these factors can lead to phase shifts from hard coral dominance to algae or other invertebrates, particularly soft corals. However, most studies have targeted the effects of single factors, leaving pronounced knowledge gaps regarding the effects of combined factors on soft corals. Here, we investigated the single and combined effects of phosphate enrichment (1, 2, and 8 μM) and seawater temperature increase (26 to 32 °C) on the soft coral Xenia umbellata by quantifying oxygen fluxes, protein content, and stable isotope signatures in a 5-week laboratory experiment. Findings revealed no significant effects of temperature increase, phosphate enrichment, and the combination of both factors on oxygen fluxes. However, regardless of the phosphate treatment, total protein content and carbon stable isotope ratios decreased significantly by 62% and 7% under temperature increase, respectively, suggesting an increased assimilation of their energy reserves. Therefore, we hypothesize that heterotrophic feeding may be important for X. umbellata to sustain their energy reserves under temperature increase, highlighting the advantages of a mixotrophic strategy. Overall, X. umbellata shows a high tolerance towards changes in global and local factors, which may explain their competitive advantage observed at many Indo-Pacific reef locations.
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Affiliation(s)
- Selma D. Mezger
- grid.7704.40000 0001 2297 4381Department of Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany
| | - Annabell Klinke
- grid.7704.40000 0001 2297 4381Department of Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany ,grid.461729.f0000 0001 0215 3324Leibniz Centre for Tropical Marine Research, Fahrenheitstraße 6, 28359 Bremen, Germany
| | - Arjen Tilstra
- grid.7704.40000 0001 2297 4381Department of Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany
| | - Yusuf C. El-Khaled
- grid.7704.40000 0001 2297 4381Department of Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany
| | - Bianca Thobor
- grid.7704.40000 0001 2297 4381Department of Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany
| | - Christian Wild
- grid.7704.40000 0001 2297 4381Department of Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Str. 6, 28359 Bremen, Germany
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7
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Thobor B, Tilstra A, Bourne DG, Springer K, Mezger SD, Struck U, Bockelmann F, Zimmermann L, Yánez Suárez AB, Klinke A, Wild C. The pulsating soft coral Xenia umbellata shows high resistance to warming when nitrate concentrations are low. Sci Rep 2022; 12:16788. [PMID: 36202937 PMCID: PMC9537297 DOI: 10.1038/s41598-022-21110-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 09/22/2022] [Indexed: 11/27/2022] Open
Abstract
The resistance of hard corals to warming can be negatively affected by nitrate eutrophication, but related knowledge for soft corals is scarce. We thus investigated the ecophysiological response of the pulsating soft coral Xenia umbellata to different levels of nitrate eutrophication (control = 0.6, medium = 6, high = 37 μM nitrate) in a laboratory experiment, with additional warming (27.7 to 32.8 °C) from days 17 to 37. High nitrate eutrophication enhanced cellular chlorophyll a content of Symbiodiniaceae by 168%, while it reduced gross photosynthesis by 56%. After additional warming, polyp pulsation rate was reduced by 100% in both nitrate eutrophication treatments, and additional polyp loss of 7% d−1 and total fragment mortality of 26% was observed in the high nitrate eutrophication treatment. Warming alone did not affect any of the investigated response parameters. These results suggest that X. umbellata exhibits resistance to warming, which may facilitate ecological dominance over some hard corals as ocean temperatures warm, though a clear negative physiological response occurs when combined with nitrate eutrophication. This study thus confirms the importance of investigating combinations of global and local factors to understand and manage changing coral reefs.
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Affiliation(s)
- Bianca Thobor
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany.
| | - Arjen Tilstra
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany
| | - David G Bourne
- College of Science and Engineering, James Cook University, 1 Angus Smith Drive, Douglas, QLD, 4814, Australia.,Australian Institute of Marine Science, Cape Ferguson, Townsville, QLD, 4810, Australia
| | - Karin Springer
- Faculty of Biology and Chemistry, Marine Botany, University of Bremen, NW2 Building, Leobener Str. 5, 28359, Bremen, Germany
| | - Selma Deborah Mezger
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany
| | - Ulrich Struck
- Museum Für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstr. 43, 10115, Berlin, Germany.,Department of Earth Sciences, Free University Berlin, Malteserstr. 74-100, Haus D, 12249, Berlin, Germany
| | - Franziska Bockelmann
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany
| | - Lisa Zimmermann
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany
| | - Ana Belén Yánez Suárez
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany
| | - Annabell Klinke
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany
| | - Christian Wild
- Faculty of Biology and Chemistry, Department of Marine Ecology, University of Bremen, UFT Building, Leobener Str. 6, 28359, Bremen, Germany
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8
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Reverter M, Helber SB, Rohde S, de Goeij JM, Schupp PJ. Coral reef benthic community changes in the Anthropocene: Biogeographic heterogeneity, overlooked configurations, and methodology. GLOBAL CHANGE BIOLOGY 2022; 28:1956-1971. [PMID: 34951504 DOI: 10.1111/gcb.16034] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 12/04/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
Non-random community changes are becoming more frequent in many ecosystems. In coral reefs, changes towards communities dominated by other than hard corals are increasing in frequency, with severe impacts on ecosystem functioning and provision of ecosystem services. Although new research suggests that a variety of alternative communities (i.e. not dominated by hard corals) exist, knowledge on the global diversity and functioning of alternative coral reef benthic communities, especially those not dominated by algae, remains scattered. In this systematic review and meta-analysis of 523 articles, we analyse the different coral reef benthic community changes reported to date and discuss the advantages and limitations of the methods used to study these changes. Furthermore, we used field cover data (1116 reefs from the ReefCheck database) to explore the biogeographic and latitudinal patterns in dominant benthic organisms. We found a mismatch between literature focus on coral-algal changes (over half of the studies analysed) and observed global natural patterns. We identified strong biogeographic patterns, with the largest and most biodiverse biogeographic regions (Western and Central Indo-Pacific) presenting previously overlooked soft-coral-dominated communities as the most abundant alternative community. Finally, we discuss the potential biases associated with methods that overlook ecologically important cryptobenthic communities and the potential of new technological advances in improving monitoring efforts. As coral reef communities inevitably and swiftly change under changing ocean conditions, there is an urgent need to better understand the distribution, dynamics as well as the ecological and societal impacts of these new communities.
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Affiliation(s)
- Miriam Reverter
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University Oldenburg, Wilhelmshaven, Germany
| | - Stephanie B Helber
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University Oldenburg, Wilhelmshaven, Germany
| | - Sven Rohde
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University Oldenburg, Wilhelmshaven, Germany
| | - Jasper M de Goeij
- Department of Freshwater and Marine Ecology (FAME), Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, The Netherlands
| | - Peter J Schupp
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University Oldenburg, Wilhelmshaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, Germany
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9
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Bozec Y, Hock K, Mason RAB, Baird ME, Castro‐Sanguino C, Condie SA, Puotinen M, Thompson A, Mumby PJ. Cumulative impacts across Australia’s Great Barrier Reef: a mechanistic evaluation. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Yves‐Marie Bozec
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | - Karlo Hock
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | - Robert A. B. Mason
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | - Mark E. Baird
- CSIRO Oceans and Atmosphere Hobart Tasmania 7001 Australia
| | - Carolina Castro‐Sanguino
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | | | - Marji Puotinen
- Australian Institute of Marine Science & Indian Ocean Marine Research Centre Crawley Western Australia 6009 Australia
| | - Angus Thompson
- Australian Institute of Marine Science Townsville Queensland 4810 Australia
| | - Peter J. Mumby
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
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10
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Regime shifts on tropical coral reef ecosystems: future trajectories to animal-dominated states in response to anthropogenic stressors. Emerg Top Life Sci 2021; 6:95-106. [PMID: 34927689 DOI: 10.1042/etls20210231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/22/2021] [Accepted: 11/25/2021] [Indexed: 02/01/2023]
Abstract
Despite the global focus on the occurrence of regime shifts on shallow-water tropical coral reefs over the last two decades, most of this research continues to focus on changes to algal-dominated states. Here, we review recent reports (in approximately the last decade) of regime shifts to states dominated by animal groups other than zooxanthellate Scleractinian corals. We found that while there have been new reports of regime shifts to reefs dominated by Ascidacea, Porifera, Octocorallia, Zoantharia, Actiniaria and azooxanthellate Scleractinian corals, some of these changes occurred many decades ago, but have only just been reported in the literature. In most cases, these reports are over small to medium spatial scales (<4 × 104 m2 and 4 × 104 to 2 × 106 m2, respectively). Importantly, from the few studies where we were able to collect information on the persistence of the regime shifts, we determined that these non-scleractinian states are generally unstable, with further changes since the original regime shift. However, these changes were not generally back to coral dominance. While there has been some research to understand how sponge- and octocoral-dominated systems may function, there is still limited information on what ecosystem services have been disrupted or lost as a result of these shifts. Given that many coral reefs across the world are on the edge of tipping points due to increasing anthropogenic stress, we urgently need to understand the consequences of non-algal coral reef regime shifts.
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11
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Lamont TAC, Williams B, Chapuis L, Prasetya ME, Seraphim MJ, Harding HR, May EB, Janetski N, Jompa J, Smith DJ, Radford AN, Simpson SD. The sound of recovery: Coral reef restoration success is detectable in the soundscape. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.14089] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Ben Williams
- Biosciences University of Exeter Exeter UK
- Centre for Biodiversity and Environment Research University College London London UK
| | | | | | - Marie J. Seraphim
- School of Health and Life Sciences University of the West of Scotland Paisley UK
| | | | | | | | - Jamaluddin Jompa
- Graduate School Universitas Hasanuddin Makassar Indonesia
- Faculty of Marine Science and Fisheries Universitas Hasanuddin Makassar Indonesia
| | - David J. Smith
- Mars Incorporated London UK
- Coral Reef Research Unit School of Life Sciences University of Essex Colchester UK
| | | | - Stephen D. Simpson
- Biosciences University of Exeter Exeter UK
- School of Biological Sciences University of Bristol Bristol UK
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12
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Warne DJ, Crossman KA, Jin W, Mengersen K, Osborne K, Simpson MJ, Thompson AA, Wu P, Ortiz J. Identification of two‐phase recovery for interpretation of coral reef monitoring data. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.14039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David J. Warne
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | | | - Wang Jin
- The Kirby Institute University of New South Wales Sydney New South Wales Australia
| | - Kerrie Mengersen
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | - Kate Osborne
- Australian Institute of Marine Science Townsville Qld. Australia
| | - Matthew J. Simpson
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | | | - Paul Wu
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | - Juan‐C. Ortiz
- Australian Institute of Marine Science Townsville Qld. Australia
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13
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Reverter M, Jackson M, Rohde S, Moeller M, Bara R, Lasut MT, Segre Reinach M, Schupp PJ. High taxonomic resolution surveys and trait-based analyses reveal multiple benthic regimes in North Sulawesi (Indonesia). Sci Rep 2021; 11:16554. [PMID: 34400684 PMCID: PMC8367970 DOI: 10.1038/s41598-021-95905-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 07/29/2021] [Indexed: 02/07/2023] Open
Abstract
As coral reef communities change and reorganise in response to increasing disturbances, there is a growing need for understanding species regimes and their contribution to ecosystem processes. Using a case study on coral reefs at the epicentre of tropical marine biodiversity (North Sulawesi, Indonesia), we explored how application of different biodiversity approaches (i.e., use of major taxonomic categories, high taxonomic resolution categories and trait-based approaches) affects the detection of distinct fish and benthic communities. Our results show that using major categories fails to identify distinct coral reef regimes. We also show that monitoring of only scleractinian coral communities is insufficient to detect different benthic regimes, especially communities dominated by non-coral organisms, and that all types of benthic organisms need to be considered. We have implemented the use of a trait-based approach to study the functional diversity of whole coral reef benthic assemblages, which allowed us to detect five different community regimes, only one of which was dominated by scleractinian corals. Furthermore, by the parallel study of benthic and fish communities we provide new insights into key processes and functions that might dominate or be compromised in the different community regimes.
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Affiliation(s)
- Miriam Reverter
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany.
| | - Matthew Jackson
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
| | - Sven Rohde
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
| | - Mareen Moeller
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
| | - Robert Bara
- Faculty of Fisheries and Marine Science, Sam Ratulangi University, Jl. Kampus UNSRAT Bahu, 95115, Manado, Sulawesi Utara, Indonesia
| | - Markus T Lasut
- Faculty of Fisheries and Marine Science, Sam Ratulangi University, Jl. Kampus UNSRAT Bahu, 95115, Manado, Sulawesi Utara, Indonesia
| | | | - Peter J Schupp
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), 26129, Oldenburg, Germany
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14
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Gouezo M, Fabricius K, Harrison P, Golbuu Y, Doropoulos C. Optimizing coral reef recovery with context-specific management actions at prioritized reefs. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 295:113209. [PMID: 34346392 DOI: 10.1016/j.jenvman.2021.113209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/06/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Assisting the natural recovery of coral reefs through local management actions is needed in response to increasing ecosystem disturbances in the Anthropocene. There is growing evidence that commonly used resilience-based passive management approaches may not be sufficient to maintain coral reef key functions. We synthesize and discuss advances in coral reef recovery research, and its application to coral reef conservation and restoration practices. We then present a framework to guide the decision-making of reef managers, scientists and other stakeholders, to best support reef recovery after a disturbance. The overall aim of this management framework is to catalyse reef recovery, to minimize recovery times, and to limit the need for ongoing management interventions into the future. Our framework includes two main stages: first, a prioritization method for assessment following a large-scale disturbance, which is based on a reef's social-ecological values, and on a classification of the likelihood of recovery or succession resulting in degraded, novel, hybrid or historical states. Second, a flow chart to assist with determining management actions for highly valued reefs. Potential actions are chosen based on the ecological attributes of the disturbed reef, defined during ecological assessments. Depending on the context, management actions may include (1) substrata rehabilitation actions to facilitate natural coral recruitment, (2) repopulating actions using active restoration techniques, (3) resilience-based management actions and (4) monitoring coral recruitment and growth to assess the effectiveness of management interventions. We illustrate the proposed decision framework with a case study of typhoon-damaged eastern outer reefs in Palau, Micronesia. The decisions made following this framework lead to the conclusion that some reefs may not return to their historical state for many decades. However, if motivation and funds are available, new management approaches can be explored to assist coral reefs at valued locations to return to a functional state providing key ecosystem services.
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Affiliation(s)
- Marine Gouezo
- Palau International Coral Reef Center, PO Box 7086, Koror, Palau; Marine Ecology Research Centre, Southern Cross University, PO Box 157, Lismore, NSW 2480, Australia.
| | - Katharina Fabricius
- Australian Institute of Marine Science, PMB 3, Townsville, QLD 4810, Australia.
| | - Peter Harrison
- Marine Ecology Research Centre, Southern Cross University, PO Box 157, Lismore, NSW 2480, Australia.
| | - Yimnang Golbuu
- Palau International Coral Reef Center, PO Box 7086, Koror, Palau.
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15
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El-Khaled YC, Roth F, Rädecker N, Tilstra A, Karcher DB, Kürten B, Jones BH, Voolstra CR, Wild C. Nitrogen fixation and denitrification activity differ between coral- and algae-dominated Red Sea reefs. Sci Rep 2021; 11:11820. [PMID: 34083565 PMCID: PMC8175748 DOI: 10.1038/s41598-021-90204-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 05/07/2021] [Indexed: 11/18/2022] Open
Abstract
Coral reefs experience phase shifts from coral- to algae-dominated benthic communities, which could affect the interplay between processes introducing and removing bioavailable nitrogen. However, the magnitude of such processes, i.e., dinitrogen (N2) fixation and denitrification levels, and their responses to phase shifts remain unknown in coral reefs. We assessed both processes for the dominant species of six benthic categories (hard corals, soft corals, turf algae, coral rubble, biogenic rock, and reef sands) accounting for > 98% of the benthic cover of a central Red Sea coral reef. Rates were extrapolated to the relative benthic cover of the studied organisms in co-occurring coral- and algae-dominated areas of the same reef. In general, benthic categories with high N2 fixation exhibited low denitrification activity. Extrapolated to the respective reef area, turf algae and coral rubble accounted for > 90% of overall N2 fixation, whereas corals contributed to more than half of reef denitrification. Total N2 fixation was twice as high in algae- compared to coral-dominated areas, whereas denitrification levels were similar. We conclude that algae-dominated reefs promote new nitrogen input through enhanced N2 fixation and comparatively low denitrification. The subsequent increased nitrogen availability could support net productivity, resulting in a positive feedback loop that increases the competitive advantage of algae over corals in reefs that experienced a phase shift.
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Affiliation(s)
- Yusuf C El-Khaled
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany.
| | - Florian Roth
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Baltic Sea Centre, Stockholm University, 10691, Stockholm, Sweden
- Faculty of Biological and Environmental Sciences, Tvärminne Zoological Station, University of Helsinki, 00014, Helsinki, Finland
| | - Nils Rädecker
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Arjen Tilstra
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany
| | - Denis B Karcher
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany
- Australian National Centre for the Public Awareness of Science, Australian National University, ACT, Canberra, 2601, Australia
| | - Benjamin Kürten
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Project Management Jülich, Jülich Research Centre GmbH, 18069, Rostock, Germany
| | - Burton H Jones
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
| | - Christian R Voolstra
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany
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16
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Desai RM, Shambaugh GE. Measuring the global impact of destructive and illegal fishing on maritime piracy: A spatial analysis. PLoS One 2021; 16:e0246835. [PMID: 33626091 PMCID: PMC7904167 DOI: 10.1371/journal.pone.0246835] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 01/27/2021] [Indexed: 11/20/2022] Open
Abstract
Maritime piracy constitutes a major threat to global shipping and international trade. We argue that fishers turn to piracy to smooth expected income losses and to deter illegal foreign fishing fleets. Previous investigations have generally focused on cross-national determinants of the incidence of piracy in territorial waters. These investigations neglect piracy in international waters and ignore its spatial dependence, whereby pirate attacks cluster in certain locations due to neighborhood and spillover effects. We conduct a geographically disaggregated analysis using geo-referenced data of piracy and its covariates between 2005 and 2014. We demonstrate that the incidence of piracy in a particular location is associated with higher catch volumes from high-bycatch and habitat-destroying fishing, even when controlling for conditions in proximate coastal areas. We find, additionally, that illegal, unreported, and unregulated fishing exerts an especially pronounced effect on piracy. These findings highlight the need for anti-piracy solutions beyond enforcement to include the policing of fishing practices that are illegal or are perceived by local fishers in vulnerable coastal areas to be harmful to small-scale fishing economies.
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Affiliation(s)
- Raj M. Desai
- Edmund A. Walsh School of Foreign Service, Georgetown University, Washington, District of Columbia, United States of America
- Department of Government, Georgetown University, Washington, District of Columbia, United States of America
- The Brookings Institution, Washington, District of Columbia, United States of America
- * E-mail:
| | - George E. Shambaugh
- Edmund A. Walsh School of Foreign Service, Georgetown University, Washington, District of Columbia, United States of America
- Department of Government, Georgetown University, Washington, District of Columbia, United States of America
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17
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Ceccarelli DM, McLeod IM, Boström-Einarsson L, Bryan SE, Chartrand KM, Emslie MJ, Gibbs MT, Gonzalez Rivero M, Hein MY, Heyward A, Kenyon TM, Lewis BM, Mattocks N, Newlands M, Schläppy ML, Suggett DJ, Bay LK. Substrate stabilisation and small structures in coral restoration: State of knowledge, and considerations for management and implementation. PLoS One 2020; 15:e0240846. [PMID: 33108387 PMCID: PMC7591095 DOI: 10.1371/journal.pone.0240846] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Coral reef ecosystems are under increasing pressure from local and regional stressors and a changing climate. Current management focuses on reducing stressors to allow for natural recovery, but in many areas where coral reefs are damaged, natural recovery can be restricted, delayed or interrupted because of unstable, unconsolidated coral fragments, or rubble. Rubble fields are a natural component of coral reefs, but repeated or high-magnitude disturbances can prevent natural cementation and consolidation processes, so that coral recruits fail to survive. A suite of interventions have been used to target this issue globally, such as using mesh to stabilise rubble, removing the rubble to reveal hard substrate and deploying rocks or other hard substrates over the rubble to facilitate recruit survival. Small, modular structures can be used at multiple scales, with or without attached coral fragments, to create structural complexity and settlement surfaces. However, these can introduce foreign materials to the reef, and a limited understanding of natural recovery processes exists for the potential of this type of active intervention to successfully restore local coral reef structure. This review synthesises available knowledge about the ecological role of coral rubble, natural coral recolonisation and recovery rates and the potential benefits and risks associated with active interventions in this rapidly evolving field. Fundamental knowledge gaps include baseline levels of rubble, the structural complexity of reef habitats in space and time, natural rubble consolidation processes and the risks associated with each intervention method. Any restoration intervention needs to be underpinned by risk assessment, and the decision to repair rubble fields must arise from an understanding of when and where unconsolidated substrate and lack of structure impair natural reef recovery and ecological function. Monitoring is necessary to ascertain the success or failure of the intervention and impacts of potential risks, but there is a strong need to specify desired outcomes, the spatial and temporal context and indicators to be measured. With a focus on the Great Barrier Reef, we synthesise the techniques, successes and failures associated with rubble stabilisation and the use of small structures, review monitoring methods and indicators, and provide recommendations to ensure that we learn from past projects.
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Affiliation(s)
- Daniela M. Ceccarelli
- Marine Ecology Consultant, Nelly Bay, QLD, Australia
- ARC Centre of Excellence for Coral Reef Studies, Townsville, QLD, Australia
- * E-mail: (DMC); (IMM)
| | - Ian M. McLeod
- TropWATER (Centre for Tropical Water and Aquatic Ecosystem Research), James Cook University, Townsville, Queensland, Australia
- * E-mail: (DMC); (IMM)
| | - Lisa Boström-Einarsson
- TropWATER (Centre for Tropical Water and Aquatic Ecosystem Research), James Cook University, Townsville, Queensland, Australia
- Lancaster Environment Centre, Lancaster University, Lancaster, United Kingdom
| | - Scott E. Bryan
- School of Earth & Atmospheric Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Kathryn M. Chartrand
- TropWATER (Centre for Tropical Water and Aquatic Ecosystem Research), James Cook University, Townsville, Queensland, Australia
| | - Michael J. Emslie
- Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, Queensland, Australia
| | - Mark T. Gibbs
- Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, Queensland, Australia
- Division of Business Development, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Manuel Gonzalez Rivero
- Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, Queensland, Australia
| | - Margaux Y. Hein
- TropWATER (Centre for Tropical Water and Aquatic Ecosystem Research), James Cook University, Townsville, Queensland, Australia
| | - Andrew Heyward
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre, University of Western Australia, Crawley, Western Australia, Australia
| | - Tania M. Kenyon
- Marine Spatial Ecology Lab, The University of Queensland, St. Lucia, Queensland, Australia
| | - Brett M. Lewis
- School of Earth & Atmospheric Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Neil Mattocks
- Reef Joint Field Management Program, Great Barrier Reef Marine Park Authority, Townsville, Queensland, Australia
| | - Maxine Newlands
- TropWATER (Centre for Tropical Water and Aquatic Ecosystem Research), James Cook University, Townsville, Queensland, Australia
- School of Social Science, James Cook University, Townsville, Queensland, Australia
| | - Marie-Lise Schläppy
- Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, Queensland, Australia
- Faculty of Engineering, Oceans Graduate School, The University of Western Australia, Crawley, WA, Australia
| | - David J. Suggett
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Line K. Bay
- Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, Queensland, Australia
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18
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Seraphim MJ, Sloman KA, Alexander ME, Janetski N, Jompa J, Ambo-Rappe R, Snellgrove D, Mars F, Harborne AR. Interactions between coral restoration and fish assemblages: implications for reef management. JOURNAL OF FISH BIOLOGY 2020; 97:633-655. [PMID: 32564370 DOI: 10.1111/jfb.14440] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 06/01/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
Corals create complex reef structures that provide both habitat and food for many fish species. Because of numerous natural and anthropogenic threats, many coral reefs are currently being degraded, endangering the fish assemblages they support. Coral reef restoration, an active ecological management tool, may help reverse some of the current trends in reef degradation through the transplantation of stony corals. Although restoration techniques have been extensively reviewed in relation to coral survival, our understanding of the effects of adding live coral cover and complexity on fishes is in its infancy with a lack of scientifically validated research. This study reviews the limited data on reef restoration and fish assemblages, and complements this with the more extensive understanding of complex interactions between natural reefs and fishes and how this might inform restoration efforts. It also discusses which key fish species or functional groups may promote, facilitate or inhibit restoration efforts and, in turn, how restoration efforts can be optimised to enhance coral fish assemblages. By highlighting critical knowledge gaps in relation to fishes and restoration interactions, the study aims to stimulate research into the role of reef fishes in restoration projects. A greater understanding of the functional roles of reef fishes would also help inform whether restoration projects can return fish assemblages to their natural compositions or whether alternative species compositions develop, and over what timeframe. Although alleviation of local and global reef stressors remains a priority, reef restoration is an important tool; an increased understanding of the interactions between replanted corals and the fishes they support is critical for ensuring its success for people and nature.
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Affiliation(s)
- Marie J Seraphim
- School of Health and Life Sciences, University of the West of Scotland, Paisley, UK
| | - Katherine A Sloman
- School of Health and Life Sciences, University of the West of Scotland, Paisley, UK
| | - Mhairi E Alexander
- School of Health and Life Sciences, University of the West of Scotland, Paisley, UK
| | | | - Jamaluddin Jompa
- Faculty of Marine Science and Fisheries, Hasanuddin University, Makassar, Indonesia
| | - Rohani Ambo-Rappe
- Faculty of Marine Science and Fisheries, Hasanuddin University, Makassar, Indonesia
| | - Donna Snellgrove
- Waltham Petcare Science Institute, Melton Mowbray, Leicestershire, UK
| | | | - Alastair R Harborne
- Institute of Environment and Department of Biological Sciences, Florida International University, North Miami, Florida, USA
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19
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Raphael A, Dubinsky Z, Iluz D, Benichou JIC, Netanyahu NS. Deep neural network recognition of shallow water corals in the Gulf of Eilat (Aqaba). Sci Rep 2020; 10:12959. [PMID: 32737327 PMCID: PMC7395127 DOI: 10.1038/s41598-020-69201-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 07/01/2020] [Indexed: 11/08/2022] Open
Abstract
We describe the application of the computerized deep learning methodology to the recognition of corals in a shallow reef in the Gulf of Eilat, Red Sea. This project is aimed at applying deep neural network analysis, based on thousands of underwater images, to the automatic recognition of some common species among the 100 species reported to be found in the Eilat coral reefs. This is a challenging task, since even in the same colony, corals exhibit significant within-species morphological variability, in terms of age, depth, current, light, geographic location, and inter-specific competition. Since deep learning procedures are based on photographic images, the task is further challenged by image quality, distance from the object, angle of view, and light conditions. We produced a large dataset of over 5,000 coral images that were classified into 11 species in the present automated deep learning classification scheme. We demonstrate the efficiency and reliability of the method, as compared to painstaking manual classification. Specifically, we demonstrated that this method is readily adaptable to include additional species, thereby providing an excellent tool for future studies in the region, that would allow for real time monitoring the detrimental effects of global climate change and anthropogenic impacts on the coral reefs of the Gulf of Eilat and elsewhere, and that would help assess the success of various bioremediation efforts.
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Affiliation(s)
- Alina Raphael
- Faculty of Life Sciences, The Mina and Everard Goodman, Bar-Ilan University, 5290002, Ramat-Gan, Israel.
| | - Zvy Dubinsky
- Faculty of Life Sciences, The Mina and Everard Goodman, Bar-Ilan University, 5290002, Ramat-Gan, Israel
| | - David Iluz
- Faculty of Life Sciences, The Mina and Everard Goodman, Bar-Ilan University, 5290002, Ramat-Gan, Israel
- Department of Environmental Sciences and Agriculture, Beit Berl College, 4490500, Beit Berl, Israel
| | - Jennifer I C Benichou
- Faculty of Life Sciences, The Mina and Everard Goodman, Bar-Ilan University, 5290002, Ramat-Gan, Israel
| | - Nathan S Netanyahu
- Department of Computer Science, Bar-Ilan University, 5290002, Ramat-Gan, Israel
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20
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Vollstedt S, Xiang N, Simancas-Giraldo SM, Wild C. Organic eutrophication increases resistance of the pulsating soft coral Xenia umbellata to warming. PeerJ 2020; 8:e9182. [PMID: 32607278 PMCID: PMC7316076 DOI: 10.7717/peerj.9182] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 04/22/2020] [Indexed: 11/21/2022] Open
Abstract
Recent research indicates that hard corals in a process that is termed phase shift are often replaced by soft corals in reefs. The simultaneous occurrence of local (i.e. organic eutrophication as highly under-investigated parameter) and global (i.e. ocean warming) factors may facilitate these phase shifts as hard corals are negatively affected by both ocean warming and organic eutrophication. Knowledge about soft coral responses to environmental change remains incomplete, although these organisms are becoming important players in reefs. The present study thus investigated the individual and combined effects of organic eutrophication (as glucose addition) and warming on the ecological data of the pulsating soft coral Xenia umbellata. We assessed health status, growth and pulsation rates of soft corals in a 45 day aquarium experiment, with first manipulation of organic eutrophication (no, low, medium and high glucose addition) over 21 days followed by step-wise increases in water temperature from 26 to 32 °C over 24 days. Findings revealed that glucose addition did not affect health status, growth and pulsation rates of the investigated soft corals. Under simulated ocean warming, soft corals that had experienced organic eutrophication before, maintained significantly higher pulsation rates (averaging 22 beats per minute—bpm) and no mortality compared to the controls that showed a decrease of 56% (averaging 15 bpm) in pulsation rates and mortality of 30% at water temperatures of 32 °C compared to 26 °C. This apparently positive effect of organic eutrophication on the ecological data of soft corals under an ocean warming scenario decreased with increasing water temperature. This study thus indicates that (a) organic eutrophication as additional energy source up to a certain threshold may increase the resistance of soft corals to ocean warming and (b) pulsation rates of soft corals may be used as inexpensive, easily detectable, and non-invasive early warning indicator for ocean warming effects on benthic reef communities. When comparing findings of this study for soft corals with previous results for hard corals, it can be assumed that soft corals under the predicted increases of organic eutrophication and warming gain more and more competitive advantages. This may further facilitate phase shifts from hard to soft corals in warming reefs.
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Affiliation(s)
- Svea Vollstedt
- Faculty of Biology and Chemistry, Universität Bremen, Bremen, Germany
| | - Nan Xiang
- Faculty of Biology and Chemistry, Universität Bremen, Bremen, Germany.,WG Tropical Marine Microbiology, Leibniz Centre for Tropical Marine Research, Bremen, Germany
| | | | - Christian Wild
- Faculty of Biology and Chemistry, Universität Bremen, Bremen, Germany
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21
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Abstract
We present thorough this review the developments in the field, point out their current limitations, and outline its timelines and unique potential. In order to do so we introduce the methods used in each of the advances in the application of deep learning (DL) to coral research that took place between the years: 2016–2018. DL has unique capability of streamlining the description, analysis, and monitoring of coral reefs, saving time, and obtaining higher reliability and accuracy compared with error-prone human performance. Coral reefs are the most diverse and complex of marine ecosystems, undergoing a severe decline worldwide resulting from the adverse synergistic influences of global climate change, ocean acidification, and seawater warming, exacerbated by anthropogenic eutrophication and pollution. DL is an extension of some of the concepts originating from machine learning that join several multilayered neural networks. Machine learning refers to algorithms that automatically detect patterns in data. In the case of corals these data are underwater photographic images. Based on “learned” patterns, such programs can recognize new images. The novelty of DL is in the use of state-of-art computerized image analyses technologies, and its fully automated methodology of dealing with large data sets of images. Automated Image recognition refers to technologies that identify and detect objects or attributes in a digital video or image automatically. Image recognition classifies data into selected categories out of many. We show that Neural Network methods are already reliable in distinguishing corals from other benthos and non-coral organisms. Automated recognition of live coral cover is a powerful indicator of reef response to slow and transient changes in the environment. Improving automated recognition of coral species, DL methods already recognize decline of coral diversity due to natural and anthropogenic stressors. Diversity indicators can document the effectiveness of reef bioremediation initiatives. We explored the current applications of deep learning for corals and benthic image classification by discussing the most recent studies conducted by researchers. We review the developments in the field, point out their current limitations, and outline their timelines and unique potential. We also discussed a few future research directions in the fields of deep learning. Future needs are the age detection of single species, in order to track trends in their population recruitment, decline, and recovery. Fine resolution, at the polyp level, is still to be developed, in order to allow separation of species with similar macroscopic features. That refinement of DL will allow such comparisons and their analyses. We conclude that the usefulness of future, more refined automatic identification will allow reef comparison, and tracking long term changes in species diversity. The hitherto unused addition of intraspecific coral color parameters, will add the inclusion of physiological coral responses to environmental conditions and change thereof. The core aim of this review was to underscore the strength and reliability of the DL approach for documenting coral reef features based on an evaluation of the currently available published uses of this method. We expect that this review will encourage researchers from computer vision and marine societies to collaborate on similar long-term joint ventures.
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22
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Fox HE, Harris JL, Darling ES, Ahmadia GN, Estradivari, Razak TB. Rebuilding coral reefs: success (and failure) 16 years after low‐cost, low‐tech restoration. Restor Ecol 2019. [DOI: 10.1111/rec.12935] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Helen E. Fox
- Science and Exploration, National Geographic Society 1145 17th Street NW, Washington DC 20036 U.S.A
| | - Jill L. Harris
- Oceans Conservation Program, World Wildlife Fund‐US 1250 24th Street NW, Washington DC 20037 U.S.A
| | - Emily S. Darling
- Marine Program, Wildlife Conservation Society 2300 Southern Boulevard, Bronx NY 10460 U.S.A
| | - Gabby N. Ahmadia
- Oceans Conservation Program, World Wildlife Fund‐US 1250 24th Street NW, Washington DC 20037 U.S.A
| | - Estradivari
- Marine and Fisheries DirectorateWWF‐Indonesia Jakarta Indonesia
| | - Tries B. Razak
- Faculty of Fisheries and Marine Sciences, Universitas Padjadjaran Jl. Raya Bandung-Sumedang Km. 21 UBR Jatinangor 45363 Indonesia
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23
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Valderrama Ballesteros L, Matthews JL, Hoeksema BW. Pollution and coral damage caused by derelict fishing gear on coral reefs around Koh Tao, Gulf of Thailand. MARINE POLLUTION BULLETIN 2018; 135:1107-1116. [PMID: 30301009 DOI: 10.1016/j.marpolbul.2018.08.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 08/15/2018] [Accepted: 08/17/2018] [Indexed: 05/12/2023]
Abstract
Most lost fishing gear is made of non-biodegradable plastics that may sink to the sea floor or drift around in currents. It may remain unnoticed until it shows up on coral reefs, beaches and in other coastal habitats. Stony corals have fragile skeletons and soft tissues that can easily become damaged when they get in contact with lost fishing gear. During a dive survey around Koh Tao, a small island in the Gulf of Thailand, the impact of lost fishing gear (nets, ropes, cages, lines) was studied on corals representing six different growth forms: branching, encrusting, foliaceous, free-living, laminar, and massive. Most gear (>95%) contained plastic. Besides absence of damage (ND), three categories of coral damage were assessed: fresh tissue loss (FTL), tissue loss with algal growth (TLAG), and fragmentation (FR). The position of the corals in relation to the fishing gear was recorded as either growing underneath (Un) or on top (On), whereas corals adjacent to the gear (Ad) were used as controls. Nets formed the dominant type of lost gear, followed by ropes, lines and cages, respectively. Branching corals were most commonly found in contact with the gear and also around it. Tubastraea micranthus was the most commonly encountered coral species, either Un, On, or Ad. Corals underneath gear showed most damage, which predominantly consisted of tissue loss. Fragmentation was less common than expected, which may be related to the low fragility of T. micranthus as dominant branching species. Even if nets serve as substrate for corals, it is recommended to remove them from reefs, where they form a major component of the plastic pollution and cause damage to corals and other reef organisms.
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Affiliation(s)
| | | | - 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.
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24
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Williams SL, Sur C, Janetski N, Hollarsmith JA, Rapi S, Barron L, Heatwole SJ, Yusuf AM, Yusuf S, Jompa J, Mars F. Large‐scale coral reef rehabilitation after blast fishing in Indonesia. Restor Ecol 2018. [DOI: 10.1111/rec.12866] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Susan L. Williams
- Bodega Marine Laboratory and Department of Evolution and Ecology University of California—Davis PO Box 247, Bodega Bay CA 94923‐2047 U.S.A
| | - Christine Sur
- Bodega Marine Laboratory and Graduate Group in Ecology University of California—Davis PO Box 247, Bodega Bay California 94923‐2047 U.S.A
| | - Noel Janetski
- Jl. Kima 10 Kav A‐6 Daya Biringkanay, Makassar South Sulawesi 90241 Indonesia
| | - Jordan A. Hollarsmith
- Bodega Marine Laboratory and Graduate Group in Ecology University of California—Davis PO Box 247, Bodega Bay California 94923‐2047 U.S.A
| | - Saipul Rapi
- Jl. Kima 10 Kav A‐6 Daya Biringkanay, Makassar South Sulawesi 90241 Indonesia
| | - Luke Barron
- Jl. Kima 10 Kav A‐6 Daya Biringkanay, Makassar South Sulawesi 90241 Indonesia
| | - Siobhan J. Heatwole
- Jl. Kima 10 Kav A‐6 Daya Biringkanay, Makassar South Sulawesi 90241 Indonesia
- School of Biological Sciences University of Wollongong Wollongong NSW 2522 Australia
| | - Andi M. Yusuf
- Jl. Kima 10 Kav A‐6 Daya Biringkanay, Makassar South Sulawesi 90241 Indonesia
| | - Syafyudin Yusuf
- Department of Marine Science and Fisheries Hasanuddin University Makassar South Sulawesi Indonesia
| | - Jamaluddin Jompa
- Department of Marine Science and Fisheries Hasanuddin University Makassar South Sulawesi Indonesia
| | - Frank Mars
- Mars, Inc. 6885 Elm St., McLean VA 22101 U.S.A
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Johns KA, Emslie MJ, Hoey AS, Osborne K, Jonker MJ, Cheal AJ. Macroalgal feedbacks and substrate properties maintain a coral reef regime shift. Ecosphere 2018. [DOI: 10.1002/ecs2.2349] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Kerryn A. Johns
- Australian Institute of Marine Science; PMB 3, Townsville MC Townsville 4810 Queensland Australia
| | - Michael J. Emslie
- Australian Institute of Marine Science; PMB 3, Townsville MC Townsville 4810 Queensland Australia
| | - Andrew S. Hoey
- ARC Centre of Excellence for Coral Reef Studies; James Cook University; Townsville 4811 Queensland Australia
| | - Kate Osborne
- Australian Institute of Marine Science; PMB 3, Townsville MC Townsville 4810 Queensland Australia
| | - Michelle J. Jonker
- Australian Institute of Marine Science; PMB 3, Townsville MC Townsville 4810 Queensland Australia
| | - Alistair J. Cheal
- Australian Institute of Marine Science; PMB 3, Townsville MC Townsville 4810 Queensland Australia
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26
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Serge A, Berny S, Philippe G, Riza FA. INDESO project: Results from application of remote sensing and numerical models for the monitoring and management of Indonesia coasts and seas. MARINE POLLUTION BULLETIN 2018; 131:1-6. [PMID: 29449006 DOI: 10.1016/j.marpolbul.2018.01.056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 01/26/2018] [Indexed: 06/08/2023]
Affiliation(s)
- Andréfouët Serge
- UMR9220 ENTROPIE, IRD, Université de la Réunion, CNRS, B.P.A5, 98848 Noumea, New Caledonia.
| | - Subky Berny
- Agency for Marine and Fisheries Research and Development - Ministry of Marine Affairs and Fisheries, Jakarta, Indonesia
| | - Gaspar Philippe
- Collecte Localisation Satellites, 8-10 rue Hermès, Toulouse, 31520, France
| | - Farhan A Riza
- Agency for Marine and Fisheries Research and Development - Ministry of Marine Affairs and Fisheries, Jakarta, Indonesia
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27
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Ampou EE, Ouillon S, Iovan C, Andréfouët S. Change detection of Bunaken Island coral reefs using 15years of very high resolution satellite images: A kaleidoscope of habitat trajectories. MARINE POLLUTION BULLETIN 2018; 131:83-95. [PMID: 29096976 DOI: 10.1016/j.marpolbul.2017.10.067] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 10/21/2017] [Accepted: 10/23/2017] [Indexed: 06/07/2023]
Abstract
In Bunaken Island (Indonesia), a time-series of very high resolution (2-4m) satellite imagery was used to draw the long-term dynamics of shallow reef flat habitats from 2001 to 2015. Lack of historical georeferenced ground-truth data oriented the analysis towards a scenario-approach based on the monitoring of selected unambiguously-changing habitat polygons characterized in situ in 2014 and 2015. Eight representative scenarios (coral colonization, coral loss, coral stability, and sand colonization by seagrass) were identified. All occurred simultaneously in close vicinity, precluding the identification of a single general cause of changes that could have affected the whole reef. Likely, very fine differences in reef topography, exposure to wind/wave and sea level variations were responsible for the variety of trajectories. While trajectories of reef habitats is a way to measure resilience and coral recovery, here, the 15-year time-series was too short to be able to conclude on the resilience of Bunaken reefs.
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Affiliation(s)
- Eghbert Elvan Ampou
- UMR9220 ENTROPIE, IRD, Université de la Réunion, CNRS, B.P.A5, 98848 Noumea, New Caledonia; Institute for Marine Research and Observation, Ministry of Marine Affairs and Fisheries, SEACORM/INDESO center, Jl. Baru Perancak, Negara-Jembrana, Bali 82251, Indonesia; Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS), Université de Toulouse, IRD, CNRS, CNES, UPS, 14 avenue Edouard-Belin, 31400 Toulouse, France.
| | - Sylvain Ouillon
- Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS), Université de Toulouse, IRD, CNRS, CNES, UPS, 14 avenue Edouard-Belin, 31400 Toulouse, France
| | - Corina Iovan
- UMR9220 ENTROPIE, IRD, Université de la Réunion, CNRS, B.P.A5, 98848 Noumea, New Caledonia
| | - Serge Andréfouët
- UMR9220 ENTROPIE, IRD, Université de la Réunion, CNRS, B.P.A5, 98848 Noumea, New Caledonia
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van de Water JAJM, Allemand D, Ferrier-Pagès C. Host-microbe interactions in octocoral holobionts - recent advances and perspectives. MICROBIOME 2018; 6:64. [PMID: 29609655 PMCID: PMC5880021 DOI: 10.1186/s40168-018-0431-6] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 03/01/2018] [Indexed: 05/05/2023]
Abstract
Octocorals are one of the most ubiquitous benthic organisms in marine ecosystems from the shallow tropics to the Antarctic deep sea, providing habitat for numerous organisms as well as ecosystem services for humans. In contrast to the holobionts of reef-building scleractinian corals, the holobionts of octocorals have received relatively little attention, despite the devastating effects of disease outbreaks on many populations. Recent advances have shown that octocorals possess remarkably stable bacterial communities on geographical and temporal scales as well as under environmental stress. This may be the result of their high capacity to regulate their microbiome through the production of antimicrobial and quorum-sensing interfering compounds. Despite decades of research relating to octocoral-microbe interactions, a synthesis of this expanding field has not been conducted to date. We therefore provide an urgently needed review on our current knowledge about octocoral holobionts. Specifically, we briefly introduce the ecological role of octocorals and the concept of holobiont before providing detailed overviews of (I) the symbiosis between octocorals and the algal symbiont Symbiodinium; (II) the main fungal, viral, and bacterial taxa associated with octocorals; (III) the dominance of the microbial assemblages by a few microbial species, the stability of these associations, and their evolutionary history with the host organism; (IV) octocoral diseases; (V) how octocorals use their immune system to fight pathogens; (VI) microbiome regulation by the octocoral and its associated microbes; and (VII) the discovery of natural products with microbiome regulatory activities. Finally, we present our perspectives on how the field of octocoral research should move forward, and the recognition that these organisms may be suitable model organisms to study coral-microbe symbioses.
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Affiliation(s)
| | - Denis Allemand
- Centre Scientifique de Monaco, 8 Quai Antoine 1er, 98000, Monaco, Monaco
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29
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Showen R, Dunson C, Woodman GH, Christopher S, Lim T, Wilson SC. Locating fish bomb blasts in real-time using a networked acoustic system. MARINE POLLUTION BULLETIN 2018; 128:496-507. [PMID: 29571401 DOI: 10.1016/j.marpolbul.2018.01.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 01/13/2018] [Accepted: 01/15/2018] [Indexed: 06/08/2023]
Abstract
Results are presented of a demonstration of real-time fish blast location in Sabah, Malaysia using a networked hydroacoustic array based on the ShotSpotter gunshot location system. A total of six acoustic sensors - some fixed and others mobile - were deployed at ranges from 1 to 9 km to detect signals from controlled test blasts. This allowed the blast locations to be determined to within 60 m accuracy, and for the calculated locations to be displayed on a map on designated internet-connected computers within 10 s. A smaller three-sensor system was then installed near Semporna in Eastern Sabah that determined the locations of uncontrolled blasts set off by local fishermen. The success of these demonstrations shows that existing technology can be used to protect reefs and permit more effective management of blast fishing activity through improved detection and enforcement measures and enhanced community engagement.
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Affiliation(s)
- R Showen
- ShotSpotter Inc., Suite 210, 7979 Gateway Blvd, Newark, CA 94560, USA.
| | - C Dunson
- ShotSpotter Inc., Suite 210, 7979 Gateway Blvd, Newark, CA 94560, USA
| | - G H Woodman
- Teng Hoi Conservation Organization, Room 1906, 19/F, China Insurance Group Building, 141 Des Voeux Road, Central, Hong Kong
| | - S Christopher
- Scubazoo Images Sdn. Bhd., 3, Jalan Nosoob Hungab, 88300 Kota Kinabalu, Sabah, Malaysia
| | - T Lim
- Scubazoo Images Sdn. Bhd., 3, Jalan Nosoob Hungab, 88300 Kota Kinabalu, Sabah, Malaysia
| | - S C Wilson
- Five Oceans Environmental Services LLC, P.O. Box 660, Postal Code 131, Hamriyah, Oman
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Baum G, Januar I, Ferse SCA, Wild C, Kunzmann A. Abundance and physiology of dominant soft corals linked to water quality in Jakarta Bay, Indonesia. PeerJ 2016; 4:e2625. [PMID: 27904802 PMCID: PMC5127238 DOI: 10.7717/peerj.2625] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 09/25/2016] [Indexed: 12/03/2022] Open
Abstract
Declining water quality is one of the main reasons of coral reef degradation in the Thousand Islands off the megacity Jakarta, Indonesia. Shifts in benthic community composition to higher soft coral abundances have been reported for many degraded reefs throughout the Indo-Pacific. However, it is not clear to what extent soft coral abundance and physiology are influenced by water quality. In this study, live benthic cover and water quality (i.e. dissolved inorganic nutrients (DIN), turbidity (NTU), and sedimentation) were assessed at three sites (< 20 km north of Jakarta) in Jakarta Bay (JB) and five sites along the outer Thousand Islands (20–60 km north of Jakarta). This was supplemented by measurements of photosynthetic yield and, for the first time, respiratory electron transport system (ETS) activity of two dominant soft coral genera, Sarcophyton spp. and Nephthea spp. Findings revealed highly eutrophic water conditions in JB compared to the outer Thousand Islands, with 44% higher DIN load (7.65 μM/L), 67% higher NTU (1.49 NTU) and 47% higher sedimentation rate (30.4 g m−2 d−1). Soft corals were the dominant type of coral cover within the bay (2.4% hard and 12.8% soft coral cover) compared to the outer Thousand Islands (28.3% hard and 6.9% soft coral cover). Soft coral abundances, photosynthetic yield, and ETS activity were highly correlated with key water quality parameters, particularly DIN and sedimentation rates. The findings suggest water quality controls the relative abundance and physiology of dominant soft corals in JB and may thus contribute to phase shifts from hard to soft coral dominance, highlighting the need to better manage water quality in order to prevent or reverse phase shifts.
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Affiliation(s)
- Gunilla Baum
- Department of Ecology, Leibniz Center for Tropical Marine Ecology, Bremen, Germany; Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Indra Januar
- Indonesian Research Center for Marine and Fisheries Products Processing and Biotechnology , Jakarta, Jakarta Pusat , Indonesia
| | - Sebastian C A Ferse
- Department of Ecology, Leibniz Center for Tropical Marine Ecology , Bremen , Germany
| | - Christian Wild
- Faculty of Biology and Chemistry, University of Bremen , Bremen , Germany
| | - Andreas Kunzmann
- Department of Ecology, Leibniz Center for Tropical Marine Ecology , Bremen , Germany
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32
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Murphy JWA, Richmond RH. Changes to coral health and metabolic activity under oxygen deprivation. PeerJ 2016; 4:e1956. [PMID: 27114888 PMCID: PMC4841221 DOI: 10.7717/peerj.1956] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 03/31/2016] [Indexed: 11/20/2022] Open
Abstract
On Hawaiian reefs, the fast-growing, invasive algae Gracilaria salicornia overgrows coral heads, restricting water flow and light, thereby smothering corals. Field data shows hypoxic conditions (dissolved oxygen (DO2) < 2 mg/L) occurring underneath algal mats at night, and concurrent bleaching and partial tissue loss of shaded corals. To analyze the impact of nighttime oxygen-deprivation on coral health, this study evaluated changes in coral metabolism through the exposure of corals to chronic hypoxic conditions and subsequent analyses of lactate, octopine, alanopine, and strombine dehydrogenase activities, critical enzymes employed through anaerobic respiration. Following treatments, lactate and octopine dehydrogenase activities were found to have no significant response in activities with treatment and time. However, corals subjected to chronic nighttime hypoxia were found to exhibit significant increases in alanopine dehydrogenase activity after three days of exposure and strombine dehydrogenase activity starting after one overnight exposure cycle. These findings provide new insights into coral metabolic shifts in extremely low-oxygen environments and point to ADH and SDH assays as tools for quantifying the impact of hypoxia on coral health.
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Affiliation(s)
- James W A Murphy
- Kewalo Marine Laboratory, Pacific Biosciences Research Center, University of Hawaii at Manoa , Honolulu, HI , United States
| | - Robert H Richmond
- Kewalo Marine Laboratory, Pacific Biosciences Research Center, University of Hawaii at Manoa , Honolulu, HI , United States
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Coral Reefs at the Northernmost Tip of Borneo: An Assessment of Scleractinian Species Richness Patterns and Benthic Reef Assemblages. PLoS One 2015; 10:e0146006. [PMID: 26719987 PMCID: PMC4697805 DOI: 10.1371/journal.pone.0146006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 12/11/2015] [Indexed: 11/25/2022] Open
Abstract
The coral reefs at the northernmost tip of Sabah, Borneo will be established under a marine protected area: the Tun Mustapha Park (TMP) by the end of 2015. This area is a passage where the Sulu Sea meets the South China Sea and it is situated at the border of the area of maximum marine biodiversity, the Coral Triangle. The TMP includes fringing and patch reefs established on a relatively shallow sea floor. Surveys were carried out to examine features of the coral reefs in terms of scleractinian species richness, and benthic reef assemblages following the Reef Check substrate categories, with emphasis on hard coral cover. Variation in scleractinian diversity was based on the species composition of coral families Fungiidae (n = 39), Agariciidae (n = 30) and Euphylliidae (n = 15). The number of coral species was highest at reefs with a larger depth gradient i.e. at the periphery of the study area and in the deep South Banggi Channel. Average live hard coral cover across the sites was 49%. Only 7% of the examined reefs had > 75% hard coral cover, while the majority of the reef sites were rated fair (51%) and good (38%). Sites with low coral cover and high rubble fragments are evidence of blast fishing, although the observed damage appeared old. Depth was a dominant factor in influencing the coral species composition and benthic reef communities in the TMP. Besides filling in the information gaps regarding species richness and benthic cover for reef areas that were previously without any data, the results of this study together with information that is already available on the coral reefs of TMP will be used to make informed decisions on zoning plans for conservation priorities in the proposed park.
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Hehre EJ, Meeuwig JJ. Differential response of fish assemblages to coral reef-based seaweed farming. PLoS One 2015; 10:e0118838. [PMID: 25822342 PMCID: PMC4378911 DOI: 10.1371/journal.pone.0118838] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 01/21/2015] [Indexed: 11/19/2022] Open
Abstract
As the global demand for seaweed-derived products drives the expansion of seaweed farming onto shallow coral ecosystems, the effects of farms on fish assemblages remain largely unexplored. Shallow coral reefs provide food and shelter for highly diverse fish assemblages but are increasingly modified by anthropogenic activities. We hypothesized that the introduction of seaweed farms into degraded shallow coral reefs had potential to generate ecological benefits for fish by adding structural complexity and a possible food source. We conducted 210 transects at 14 locations, with sampling stratified across seaweed farms and sites adjacent to and distant from farms. At a seascape scale, locations were classified by their level of exposure to human disturbance. We compared sites where (1) marine protected areas (MPAs) were established, (2) neither MPAs nor blast fishing was present (hence “unprotected”), and (3) blast fishing occurred. We observed 80,186 fish representing 148 species from 38 families. The negative effects of seaweed farms on fish assemblages appeared stronger in the absence of blast fishing and were strongest when MPAs were present, likely reflecting the positive influence of the MPAs on fish within them. Species differentiating fish assemblages with respect to seaweed farming and disturbance were typically small but also included two key target species. The propensity for seaweed farms to increase fish diversity, abundance, and biomass is limited and may reduce MPA benefits. We suggest that careful consideration be given to the placement of seaweed farms relative to MPAs.
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Affiliation(s)
- E. James Hehre
- Sea Around Us Project /Fisheries Center, University of British Columbia, Vancouver, BC, Canada
- * E-mail:
| | - J. J. Meeuwig
- School of Animal Biology and Centre for Marine Futures (Oceans Institute), University of Western Australia, Crawley, WA, Australia
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McFadden CS, Reynolds AM, Janes MP. DNA barcoding of xeniid soft corals (Octocorallia: Alcyonacea: Xeniidae) from Indonesia: species richness and phylogenetic relationships. SYST BIODIVERS 2014. [DOI: 10.1080/14772000.2014.902866] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sawall Y, Jompa J, Litaay M, Maddusila A, Richter C. Coral recruitment and potential recovery of eutrophied and blast fishing impacted reefs in Spermonde Archipelago, Indonesia. MARINE POLLUTION BULLETIN 2013; 74:374-382. [PMID: 23838417 DOI: 10.1016/j.marpolbul.2013.06.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 06/05/2013] [Accepted: 06/08/2013] [Indexed: 06/02/2023]
Abstract
Coral recruitment was assessed in highly diverse and economically important Spermonde Archipelago, a reef system subjected to land-based sources of siltation/pollution and destructive fishing, over a period of 2 years. Recruitment on settlement tiles reached up to 705 spat m(-2) yr(-1) and was strongest in the dry season (July-October), except off-shore, where larvae settled earlier. Pocilloporidae dominated near-shore, while a more diverse community of Acroporidae, Poritidae and others settled in the less polluted mid-shelf and off-shore reefs. Non-coral fouling community appeared to hardly influence initial coral settlement on the tiles, although, this does not necessarily infer low coral post-settlement mortality, which may be enhanced at the near- and off-shore reefs as indicated by increased abundances of potential space competitors on natural substrate. Blast fishing showed no local reduction in coral recruitment and live hard coral cover increased in oligotrophic reefs, indicating potential for coral recovery, if managed effectively.
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Affiliation(s)
- Yvonne Sawall
- Leibniz Center for Tropical Marine Ecology, Fahrenheitstr. 6, 28359 Bremen, Germany.
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Effect of active water movement on energy and nutrient acquisition in coral reef-associated benthic organisms. Proc Natl Acad Sci U S A 2013; 110:8767-8. [PMID: 23671104 DOI: 10.1073/pnas.1306839110] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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38
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Using community knowledge in data-deficient regions: conserving the Vulnerable dugong Dugong dugon in the Sulu Sea, Malaysia. ORYX 2013. [DOI: 10.1017/s0030605312000154] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
AbstractCommunity knowledge of the status, threats and conservation issues affecting the dugong Dugong dugon was investigated in the Sulu Sea, Malaysia. Interviews with local fishermen were conducted in 12 villages from the tip of Tanjung Inaruntung to Jambongan Island, in northern Sabah, Malaysia. According to the respondents dugong numbers are low and sightings are rare. Dugongs have been sighted around Jambongan, Tigabu, Mandidarah and Malawali Islands. The apparent decline of the dugong in this area is possibly because of incidental entanglement in nets, and opportunistic hunting. Seagrasses are present and have economic importance to the community. The fishermen have difficulty in understanding issues of conservation in relation to dugongs. I recommend that conservation initiatives begin with dialogue and an education programme, followed by incentives for development of alternative livelihoods. Using community knowledge for conservation purposes may be the only option in data-deficient regions, especially where financial constraints are high and the need for management intervention for threatened species is urgent.
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Bednarz VN, Naumann MS, Niggl W, Wild C. Inorganic nutrient availability affects organic matter fluxes and metabolic activity in the soft coral genus Xenia. ACTA ACUST UNITED AC 2012; 215:3672-9. [PMID: 22811248 DOI: 10.1242/jeb.072884] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The release of organic matter (OM) by scleractinian corals represents a key physiological process that importantly contributes to coral reef ecosystem functioning, and is affected by inorganic nutrient availability. Although OM fluxes have been studied for several dominant reef taxa, no information is available for soft corals, one of the major benthic groups in tropical reef environments. Thus, this study investigates OM fluxes along with other key physiological parameters (i.e. photosynthesis, respiration and chlorophyll a tissue content) in the common soft coral genus Xenia after a 4-week exposure period to elevated ammonium (N; 20.0 μmol l(-1)), phosphate (P; 2.0 μmol l(-1)) and combined inorganic nutrient enrichment treatment (N+P). Corals maintained without nutrient enrichment served as non-treated controls and revealed constant uptake rates for particulate organic carbon (POC) (-0.315±0.161 mg POC m(-2) coral surface area h(-1)), particulate nitrogen (PN) (-0.053±0.018 mg PN m(-2) h(-1)) and dissolved organic carbon (DOC) (-4.8±2.1 mg DOC m(-2) h(-1)). Although DOC uptake significantly increased in the N treatment, POC flux was not affected. The P treatment significantly enhanced PN release as well as photosynthesis and respiration rates, suggesting that autotrophic carbon acquisition of zooxanthellae endosymbionts influences OM fluxes by the coral host. Our physiological findings confirm the significant effect of inorganic nutrient availability on OM fluxes and key metabolic processes for the soft coral Xenia, and provide the first clues on OM cycles initiated by soft corals in reef environments exposed to ambient and elevated inorganic nutrient concentrations.
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Affiliation(s)
- Vanessa N Bednarz
- Coral Reef Ecology Group, University of Bremen and Leibniz Center for Tropical Marine Ecology, Fahrenheitstrasse 6, 28359 Bremen, Germany.
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Goatley CHR, Bellwood DR. The roles of dimensionality, canopies and complexity in ecosystem monitoring. PLoS One 2011; 6:e27307. [PMID: 22073311 PMCID: PMC3207849 DOI: 10.1371/journal.pone.0027307] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 10/13/2011] [Indexed: 11/19/2022] Open
Abstract
Canopies are common among autotrophs, increasing their access to light and thereby increasing competitive abilities. If viewed from above canopies may conceal objects beneath them creating a ‘canopy effect’. Due to complexities in collecting 3-dimensional data, most ecosystem monitoring programmes reduce dimensionality when sampling, resorting to planar views. The resultant ‘canopy effects’ may bias data interpretation, particularly following disturbances. Canopy effects are especially relevant on coral reefs where coral cover is often used to evaluate and communicate ecosystem health. We show that canopies hide benthic components including massive corals and algal turfs, and as planar views are almost ubiquitously used to monitor disturbances, the loss of vulnerable canopy-forming corals may bias findings by presenting pre-existing benthic components as an altered system. Our reliance on planar views in monitoring ecosystems, especially coral cover on reefs, needs to be reassessed if we are to better understand the ecological consequences of ever more frequent disturbances.
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Affiliation(s)
- Christopher H R Goatley
- Australian Research Council Centre of Excellence for Coral Reef Studies, and School of Marine and Tropical Biology, James Cook University, Townsville, Queensland, Australia.
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Haisfield KM, Fox HE, Yen S, Mangubhai S, Mous PJ. An ounce of prevention: cost-effectiveness of coral reef rehabilitation relative to enforcement. Conserv Lett 2010. [DOI: 10.1111/j.1755-263x.2010.00104.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Ainsworth C, Varkey D, Pitcher T. Ecosystem simulations supporting ecosystem-based fisheries management in the Coral Triangle, Indonesia. Ecol Modell 2008. [DOI: 10.1016/j.ecolmodel.2008.02.039] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Raymundo LJ, Maypa AP, Gomez ED, Cadiz P. Can dynamite-blasted reefs recover? A novel, low-tech approach to stimulating natural recovery in fish and coral populations. MARINE POLLUTION BULLETIN 2007; 54:1009-19. [PMID: 17383687 DOI: 10.1016/j.marpolbul.2007.02.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 02/05/2007] [Accepted: 02/06/2007] [Indexed: 05/14/2023]
Abstract
Throughout Southeast Asia, blast fishing creates persistent rubble fields with low coral cover and depauperate fish communities. We stabilized a 20-year-old rubble field in a Marine Protected Area in the Philippines, using plastic mesh and rock piles in replicated 17.5m(2) plots, thereby increasing topographic complexity, fish habitat, and recruitment substrate surface area. Multivariate analysis revealed fish community shifts within the rehabilitated area from that characteristic of rubble fields to one similar to the adjacent healthy reef within three years, as measured by changes in fish abundance and body size. Coral recruitment and percent cover increased over time, with 63.5% recruit survivorship within plots, compared with 6% on rubble. Our low-cost approach created a stable substrate favoring natural recovery processes. Both rehabilitation and the elimination of poaching were integral to success, emphasizing the synergism between the two and the need to incorporate both when considering mitigation.
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Affiliation(s)
- L J Raymundo
- University of Guam Marine Laboratory, UOG Station, Mangilao, GU 96923, Guam.
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Fox HE, Caldwell RL. Recovery from blast fishing on coral reefs: a tale of two scales. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2006; 16:1631-5. [PMID: 17069358 DOI: 10.1890/1051-0761(2006)016[1631:rfbfoc]2.0.co;2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Dynamite or "blast" fishing is one of the most immediate and destructive threats to coral reefs worldwide. However, little is known about the long-term ecosystem effects of such blasts or the dynamics of recovery. Here, we examine coral reef recovery in the simplest case of acute single blasts of known age, as well as recovery from chronic blasting over greater spatial and temporal scales. Rubble resulting from single blasts slowly stabilized, and craters filled in with surrounding coral and new colonies. After five years, coral cover within craters no longer differed significantly from control plots. In contrast, extensively bombed areas showed no significant recovery over the six years of this study, despite adequate supply of coral larvae. After extensive blasting, the resulting coral rubble shifts in ocean currents, forming unstable "killing fields" for new recruits. While recently tested rehabilitation methods might be feasible on a small scale, human intervention is unlikely to be effective on large spatial scales, highlighting the need for effective management to prevent blast fishing in the first place.
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Affiliation(s)
- Helen E Fox
- Department of Integrative Biology, University of California, Berkeley 94720-3140, USA.
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Dizon RM, Yap HT. Effects of multiple perturbations on the survivorship of fragments of three coral species. MARINE POLLUTION BULLETIN 2006; 52:928-34. [PMID: 16458939 DOI: 10.1016/j.marpolbul.2005.12.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Fist-sized fragments of Porites cylindrica, Porites rus and Pavona frondifera were deployed in single-species (P. cylindrica) and mixed-species (all three) plots in a shallow reef area in the northwestern Philippines. After 6 months, the corals in half of the plots were broken into smaller pieces to simulate an episodic physical disturbance. The survival of all corals was monitored from March 2000 to July 2001 during which the corals experienced 2 typhoons and episodes of algal overgrowth. For both intact and broken treatments, there was significantly higher survival in the mixed-species plots than in the single-species treatments. Fragment mortality varied between disturbances of varying frequencies and magnitudes, namely: one-time fragmentation stress, seasonal overgrowth by cyanobacteria and macroalgae, short-term (1 day) and long-term (more than 1 week) burial. The mixed-species assemblages had higher fragment survivorship than the monospecific assemblages during small-scale perturbations (e.g., algal overgrowth), but not in the face of subsequent, larger scale disturbances. This study emphasizes that coral responses to disturbance are both species- and context-specific.
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Affiliation(s)
- Romeo M Dizon
- The Marine Science Institute, University of the Philippines, Diliman, 1101 Quezon City, Philippines
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Woodman GH, Wilson SC, Li VYF, Renneberg R. A direction-sensitive underwater blast detector and its application for managing blast fishing. MARINE POLLUTION BULLETIN 2004; 49:964-973. [PMID: 15556182 DOI: 10.1016/j.marpolbul.2004.06.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/17/2004] [Indexed: 05/24/2023]
Abstract
Little is known about the spatial and temporal distribution of blast fishing which hampers enforcement against this activity. We have demonstrated that a triangular array of hydrophones 1 m apart is capable of detecting blast events whilst effectively rejecting other sources of underwater noise such as snapping shrimp and nearby boat propellers. A total of 13 blasts were recorded in Sepangor bay, North of Kota Kinabalu, Sabah, Malaysia from 7th to 15th July 2002 at distances estimated to be up to 20 km, with a directional uncertainty of 0.2 degrees . With such precision, a network of similar hydrophone arrays has potential to locate individual blast events by triangulation to within 30 m at a range of 10 km.
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Affiliation(s)
- George H Woodman
- Teng Hoi Conservation Organization, 18 Sun King Terrace, Sai Kung, Kowloon, Hong Kong.
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Cornish AS, DiDonato EM. Resurvey of a reef flat in American Samoa after 85 years reveals devastation to a soft coral (Alcyonacea) community. MARINE POLLUTION BULLETIN 2004; 48:768-777. [PMID: 15041433 DOI: 10.1016/j.marpolbul.2003.11.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
One of the earliest quantitative surveys of soft corals, on a reef flat in Pago Pago Harbour, American Samoa, was repeated 85 years later. The alcyoniid communities there, which were the dominant benthic organisms during the initial survey, have suffered a drastic decline of 99% cover in the interim. The most likely causes of the decline are anthropogenic disturbance associated with reclamation along the harbour from the 1940s to early 1960s, compounded by chronic pollution from industrial wastewater discharge from the mid-1950s to late 1980s. The decline in one dominant species, Sinularia polydactyla, is likely to have serious consequences for the reef as unusually for a soft coral, this had been the major reef building species. Life-history traits of certain Sinularia and Sarcophyton, such as slow growth and low rates of sexual reproduction, mean they will be slower to recover from severe disturbance than many scleractinian corals.
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Affiliation(s)
- Andrew S Cornish
- Department of Marine and Wildlife Resources, Pago Pago, 96799 American Samoa.
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