WorldWideScience

Sample records for coral reef ecosystems

  1. Coral reefs - Specialized ecosystems

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.

    This paper discusses briefly some aspects that characterize and differentiate coral reef ecosystems from other tropical marine ecosystems. A brief account on the resources that are extractable from coral reefs, their susceptibility to natural...

  2. Coral Reef Ecosystems

    Science.gov (United States)

    Yap, Helen T.

    Coral reefs are geological structures of significant dimensions, constructed over millions of years by calcifying organisms. The present day reef-builders are hard corals belonging to the order Scleractinia, phylum Cnidaria. The greatest concentrations of coral reefs are in the tropics, with highest levels of biodiversity situated in reefs of the Indo-West Pacific region. These ecosystems have provided coastal protection and livelihood to human populations over the millennia. Human activities have caused destruction of these habitats, the intensity of which has increased alarmingly since the latter decades of the twentieth century. The severity of this impact is directly related to exponential growth rates of human populations especially in the coastal areas of the developing world. However, a more recently recognized phenomenon concerns disturbances brought about by the changing climate, manifested mainly as rising sea surface temperatures, and increasing acidification of ocean waters due to greater drawdown of higher concentrations of atmospheric carbon dioxide. Management efforts have so far not kept pace with the rates of degradation, so that the spatial extent of damaged reefs and the incidences of localized extinction of reef species are increasing year after year. The major management efforts to date consist of establishing marine protected areas and promoting the active restoration of coral habitats.

  3. Coral reef ecosystem

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.; Wafar, S.

    communication). Fossil reefs, drowned as a result of the Holocene sea level rise, occur at 92, 85, 75 and 55 m depth along .. ~ !! ":2 0. ~ Figure 3.1 Graphical Representation of the SO-Box Model of a Caribbean Coral Reef Key: 1. Benthic producers. 2. Detritus... explain the low species diversity and the absence of branching corals in the intertidal regions. H.aised fossil reefs, proba bly as a result of local upheavals, arc found in Minicoy island (Gardiner 1903), in Ramanalhapuram district in Tamil Nadu...

  4. Coral Reef Ecosystems Monitoring Feature Service

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coral Reef Ecosystem Monitoring feature service hosted on ArcGIS Online provides access to data collected in the Mariana Archipelago by the Coral Reef Ecosystem...

  5. Cyanobacteria in coral reef ecosystems : a review

    OpenAIRE

    Charpy, L.; Casareto, B.E.; Langlade, M. J.; Suzuki, Y.

    2012-01-01

    Cyanobacteria have dominated marine environments and have been reef builders on Earth for more than three million years (myr). Cyanobacteria still play an essential role in modern coral reef ecosystems by forming a major component of epiphytic, epilithic, and endolithic communities as well as of microbial mats. Cyanobacteria are grazed by reef organisms and also provide nitrogen to the coral reef ecosystems through nitrogen fixation. Recently, new unicellular cyanobacteria that express nitrog...

  6. Bioindication in coral reef ecosystems.

    Science.gov (United States)

    Yap, H T

    1986-01-01

    The concept of bioindication in the sense of the use of organisms for detecting environmental stress has been employed in coral reef conservation and management for the past several years. Important tools are coral growth rates and various community parameters, notably hard coral cover. The present need is the optimal coordination of international efforts for the earliest possible institution of an effective monitoring system.

  7. Cyanobacteria in Coral Reef Ecosystems: A Review

    Directory of Open Access Journals (Sweden)

    L. Charpy

    2012-01-01

    Full Text Available Cyanobacteria have dominated marine environments and have been reef builders on Earth for more than three million years (myr. Cyanobacteria still play an essential role in modern coral reef ecosystems by forming a major component of epiphytic, epilithic, and endolithic communities as well as of microbial mats. Cyanobacteria are grazed by reef organisms and also provide nitrogen to the coral reef ecosystems through nitrogen fixation. Recently, new unicellular cyanobacteria that express nitrogenase were found in the open ocean and in coral reef lagoons. Furthermore, cyanobacteria are important in calcification and decalcification. All limestone surfaces have a layer of boring algae in which cyanobacteria often play a dominant role. Cyanobacterial symbioses are abundant in coral reefs; the most common hosts are sponges and ascidians. Cyanobacteria use tactics beyond space occupation to inhibit coral recruitment. Cyanobacteria can also form pathogenic microbial consortia in association with other microbes on living coral tissues, causing coral tissue lysis and death, and considerable declines in coral reefs. In deep lagoons, coccoid cyanobacteria are abundant and are grazed by ciliates, heteroflagellates, and the benthic coral reef community. Cyanobacteria produce metabolites that act as attractants for some species and deterrents for some grazers of the reef communities.

  8. Ecosystem function and biodiversity on coral reefs

    OpenAIRE

    1994-01-01

    The article highlights a workshop held in Key West, Florida in November 1993 attended by a group of 35 international scientists where topics of ecosystem function and biodiversity on coral reefs were discussed.

  9. Resetting predator baselines in coral reef ecosystems

    Science.gov (United States)

    Bradley, Darcy; Conklin, Eric; Papastamatiou, Yannis P.; McCauley, Douglas J.; Pollock, Kydd; Pollock, Amanda; Kendall, Bruce E.; Gaines, Steven D.; Caselle, Jennifer E.

    2017-01-01

    What did coral reef ecosystems look like before human impacts became pervasive? Early efforts to reconstruct baselines resulted in the controversial suggestion that pristine coral reefs have inverted trophic pyramids, with disproportionally large top predator biomass. The validity of the coral reef inverted trophic pyramid has been questioned, but until now, was not resolved empirically. We use data from an eight-year tag-recapture program with spatially explicit, capture-recapture models to re-examine the population size and density of a key top predator at Palmyra atoll, the same location that inspired the idea of inverted trophic biomass pyramids in coral reef ecosystems. Given that animal movement is suspected to have significantly biased early biomass estimates of highly mobile top predators, we focused our reassessment on the most mobile and most abundant predator at Palmyra, the grey reef shark (Carcharhinus amblyrhynchos). We estimated a density of 21.3 (95% CI 17.8, 24.7) grey reef sharks/km2, which is an order of magnitude lower than the estimates that suggested an inverted trophic pyramid. Our results indicate that the trophic structure of an unexploited reef fish community is not inverted, and that even healthy top predator populations may be considerably smaller, and more precarious, than previously thought. PMID:28220895

  10. Human impacts on Caribbean coral reef ecosystems

    OpenAIRE

    Hardt, Marah Justine

    2007-01-01

    Fishing is one of the oldest anthropogenic disturbances in the ocean, differing from other impacts in its direct removal of biomass from the ecosystem. Despite the centuries of fishing activities, there is much we still do not understand regarding the effects of fish removal on the benthic community. I use an interdisciplinary approach to investigate the affect of human disturbance, primarily the alteration of fish communities, on major functional groups of coral reefs, over extended temporal...

  11. Quantifying climatological ranges and anomalies for Pacific coral reef ecosystems.

    Science.gov (United States)

    Gove, Jamison M; Williams, Gareth J; McManus, Margaret A; Heron, Scott F; Sandin, Stuart A; Vetter, Oliver J; Foley, David G

    2013-01-01

    Coral reef ecosystems are exposed to a range of environmental forcings that vary on daily to decadal time scales and across spatial scales spanning from reefs to archipelagos. Environmental variability is a major determinant of reef ecosystem structure and function, including coral reef extent and growth rates, and the abundance, diversity, and morphology of reef organisms. Proper characterization of environmental forcings on coral reef ecosystems is critical if we are to understand the dynamics and implications of abiotic-biotic interactions on reef ecosystems. This study combines high-resolution bathymetric information with remotely sensed sea surface temperature, chlorophyll-a and irradiance data, and modeled wave data to quantify environmental forcings on coral reefs. We present a methodological approach to develop spatially constrained, island- and atoll-scale metrics that quantify climatological range limits and anomalous environmental forcings across U.S. Pacific coral reef ecosystems. Our results indicate considerable spatial heterogeneity in climatological ranges and anomalies across 41 islands and atolls, with emergent spatial patterns specific to each environmental forcing. For example, wave energy was greatest at northern latitudes and generally decreased with latitude. In contrast, chlorophyll-a was greatest at reef ecosystems proximate to the equator and northern-most locations, showing little synchrony with latitude. In addition, we find that the reef ecosystems with the highest chlorophyll-a concentrations; Jarvis, Howland, Baker, Palmyra and Kingman are each uninhabited and are characterized by high hard coral cover and large numbers of predatory fishes. Finally, we find that scaling environmental data to the spatial footprint of individual islands and atolls is more likely to capture local environmental forcings, as chlorophyll-a concentrations decreased at relatively short distances (>7 km) from 85% of our study locations. These metrics will help

  12. Quantifying climatological ranges and anomalies for Pacific coral reef ecosystems.

    Directory of Open Access Journals (Sweden)

    Jamison M Gove

    Full Text Available Coral reef ecosystems are exposed to a range of environmental forcings that vary on daily to decadal time scales and across spatial scales spanning from reefs to archipelagos. Environmental variability is a major determinant of reef ecosystem structure and function, including coral reef extent and growth rates, and the abundance, diversity, and morphology of reef organisms. Proper characterization of environmental forcings on coral reef ecosystems is critical if we are to understand the dynamics and implications of abiotic-biotic interactions on reef ecosystems. This study combines high-resolution bathymetric information with remotely sensed sea surface temperature, chlorophyll-a and irradiance data, and modeled wave data to quantify environmental forcings on coral reefs. We present a methodological approach to develop spatially constrained, island- and atoll-scale metrics that quantify climatological range limits and anomalous environmental forcings across U.S. Pacific coral reef ecosystems. Our results indicate considerable spatial heterogeneity in climatological ranges and anomalies across 41 islands and atolls, with emergent spatial patterns specific to each environmental forcing. For example, wave energy was greatest at northern latitudes and generally decreased with latitude. In contrast, chlorophyll-a was greatest at reef ecosystems proximate to the equator and northern-most locations, showing little synchrony with latitude. In addition, we find that the reef ecosystems with the highest chlorophyll-a concentrations; Jarvis, Howland, Baker, Palmyra and Kingman are each uninhabited and are characterized by high hard coral cover and large numbers of predatory fishes. Finally, we find that scaling environmental data to the spatial footprint of individual islands and atolls is more likely to capture local environmental forcings, as chlorophyll-a concentrations decreased at relatively short distances (>7 km from 85% of our study locations

  13. 77 FR 12567 - Proposed Information Collection; Comment Request; Pacific Islands Region Coral Reef Ecosystems...

    Science.gov (United States)

    2012-03-01

    ... Islands Region Coral Reef Ecosystems Logbook and Reporting AGENCY: National Oceanic and Atmospheric... Special Coral Reef Ecosystem Fishing Permit (authorized under the Fishery Management Plan for Coral Reef... the logbooks is used to obtain fish catch/fishing effort data on coral reef fishes and invertebrates...

  14. 77 FR 12243 - Proposed Information Collection; Comment Request; Pacific Islands Region Coral Reef Ecosystems...

    Science.gov (United States)

    2012-02-29

    ... Islands Region Coral Reef Ecosystems Permit Form AGENCY: National Oceanic and Atmospheric Administration... vessel to fish for Western Pacific coral reef ecosystem management unit species in the designated low-use... regulations; or (3) fishing for, taking, or retaining any Potentially Harvested Coral Reef Taxa in the coral...

  15. Coral Reef Ecosystems under Climate Change and Ocean Acidification

    Directory of Open Access Journals (Sweden)

    Ove Hoegh-Guldberg

    2017-05-01

    Full Text Available Coral reefs are found in a wide range of environments, where they provide food and habitat to a large range of organisms as well as providing many other ecological goods and services. Warm-water coral reefs, for example, occupy shallow sunlit, warm, and alkaline waters in order to grow and calcify at the high rates necessary to build and maintain their calcium carbonate structures. At deeper locations (40–150 m, “mesophotic” (low light coral reefs accumulate calcium carbonate at much lower rates (if at all in some cases yet remain important as habitat for a wide range of organisms, including those important for fisheries. Finally, even deeper, down to 2,000 m or more, the so-called “cold-water” coral reefs are found in the dark depths. Despite their importance, coral reefs are facing significant challenges from human activities including pollution, over-harvesting, physical destruction, and climate change. In the latter case, even lower greenhouse gas emission scenarios (such as Representative Concentration Pathway RCP 4.5 are likely drive the elimination of most warm-water coral reefs by 2040–2050. Cold-water corals are also threatened by warming temperatures and ocean acidification although evidence of the direct effect of climate change is less clear. Evidence that coral reefs can adapt at rates which are sufficient for them to keep up with rapid ocean warming and acidification is minimal, especially given that corals are long-lived and hence have slow rates of evolution. Conclusions that coral reefs will migrate to higher latitudes as they warm are equally unfounded, with the observations of tropical species appearing at high latitudes “necessary but not sufficient” evidence that entire coral reef ecosystems are shifting. On the contrary, coral reefs are likely to degrade rapidly over the next 20 years, presenting fundamental challenges for the 500 million people who derive food, income, coastal protection, and a range of

  16. Comparison of Coral Reef Ecosystems along a Fishing Pressure Gradient

    NARCIS (Netherlands)

    Weijerman, M.W.; Fulton, E.A.; Parrish, F.A.

    2013-01-01

    Three trophic mass-balance models representing coral reef ecosystems along a fishery gradient were compared to evaluate ecosystem effects of fishing. The majority of the biomass estimates came directly from a large-scale visual survey program; therefore, data were collected in the same way for all t

  17. 76 FR 77779 - Availability of Seats for the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve Advisory...

    Science.gov (United States)

    2011-12-14

    ... Coral Reef Ecosystem Reserve Advisory Council AGENCY: Office of National Marine Sanctuaries (ONMS... the following vacant seats on the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve Advisory....byers@noaa.gov . SUPPLEMENTARY INFORMATION: The NWHI Coral Reef Ecosystem Reserve is a ] marine...

  18. 78 FR 49258 - Fisheries in the Western Pacific; Special Coral Reef Ecosystem Fishing Permit

    Science.gov (United States)

    2013-08-13

    ... Coral Reef Ecosystem Fishing Permit AGENCY: National Marine Fisheries Service (NMFS), National Oceanic... assessment; request for comments. SUMMARY: NMFS proposes to issue a Special Coral Reef Ecosystem Fishing Permit that would authorize Kampachi Farms, LLC, to culture and harvest a coral reef ecosystem management...

  19. 77 FR 16211 - Availability of Seats for the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve Advisory...

    Science.gov (United States)

    2012-03-20

    ... Coral Reef Ecosystem Reserve Advisory Council AGENCY: Office of National Marine Sanctuaries (ONMS... the following vacant seats on the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve Advisory... . SUPPLEMENTARY INFORMATION: The NWHI Coral Reef Ecosystem Reserve is a marine protected area designed to conserve...

  20. 78 FR 66683 - Fisheries in the Western Pacific; Special Coral Reef Ecosystem Fishing Permit

    Science.gov (United States)

    2013-11-06

    ... Coral Reef Ecosystem Fishing Permit AGENCY: National Marine Fisheries Service (NMFS), National Oceanic... assessment and finding of no significant impact for the issuance of a special coral reef ecosystem fishing permit. SUMMARY: NMFS issued a Special Coral Reef Ecosystem Fishing Permit that authorizes Kampachi Farms...

  1. Current status, crisis and conservation of coral reef ecosystems in China

    OpenAIRE

    ShaoHong Wu; WenJun Zhang

    2012-01-01

    Harboring rich marine species and playing important ecological functions, coral reef ecosystems have attracted widespread concern around the world. Ecosystem diversity, conservation and management of coral reefs are becoming a hot research area. Coral reefs in China are mainly distributed in the South China Sea and Hainan, Taiwan, Hong Kong, Guangdong, and Guangxi coastal waters. In recent years, due to the global climate change and the growing impact of human activities, coral reef biodivers...

  2. Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems.

    Science.gov (United States)

    Rix, Laura; de Goeij, Jasper M; Mueller, Christina E; Struck, Ulrich; Middelburg, Jack J; van Duyl, Fleur C; Al-Horani, Fuad A; Wild, Christian; Naumann, Malik S; van Oevelen, Dick

    2016-01-07

    Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrients in DOM to higher trophic levels on Caribbean reefs via the so-called sponge loop. Coral mucus may be a major DOM source for the sponge loop, but mucus uptake by sponges has not been demonstrated. Here we used laboratory stable isotope tracer experiments to show the transfer of coral mucus into the bulk tissue and phospholipid fatty acids of the warm-water sponge Mycale fistulifera and cold-water sponge Hymedesmia coriacea, demonstrating a direct trophic link between corals and reef sponges. Furthermore, 21-40% of the mucus carbon and 32-39% of the nitrogen assimilated by the sponges was subsequently released as detritus, confirming a sponge loop on Red Sea warm-water and north Atlantic cold-water coral reefs. The presence of a sponge loop in two vastly different reef environments suggests it is a ubiquitous feature of reef ecosystems contributing to the high biogeochemical cycling that may enable coral reefs to thrive in nutrient-limited (warm-water) and energy-limited (cold-water) environments.

  3. Current status, crisis and conservation of coral reef ecosystems in China

    Directory of Open Access Journals (Sweden)

    ShaoHong Wu

    2012-03-01

    Full Text Available Harboring rich marine species and playing important ecological functions, coral reef ecosystems have attracted widespread concern around the world. Ecosystem diversity, conservation and management of coral reefs are becoming a hot research area. Coral reefs in China are mainly distributed in the South China Sea and Hainan, Taiwan, Hong Kong, Guangdong, and Guangxi coastal waters. In recent years, due to the global climate change and the growing impact of human activities, coral reef biodiversity in China have been reducing and the ecological functions of coral reef ecosystems are severely degenerating. In this paper we summarized the current status, crisis and conservation of coral reef ecosystems in China. Some progress in coral reef research was discussed.

  4. Coral Reef and Coastal Ecosystems Decision Support Workshop April 27-29, 2010 Caribbean Coral Reef Institute, La Parguera, Puerto Rico

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) and Caribbean Coral Reef Institute (CCRI) hosted a Coral Reef and Coastal Ecosystems Decision Support Workshop on April 27-28, 2010 at the Caribbean Coral Reef Institute in La Parguera, Puerto Rico. Forty-three participants, includin...

  5. Coral Reef and Coastal Ecosystems Decision Support Workshop April 27-29, 2010 Caribbean Coral Reef Institute, La Parguera, Puerto Rico

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) and Caribbean Coral Reef Institute (CCRI) hosted a Coral Reef and Coastal Ecosystems Decision Support Workshop on April 27-28, 2010 at the Caribbean Coral Reef Institute in La Parguera, Puerto Rico. Forty-three participants, includin...

  6. How models can support ecosystem-based management of coral reefs

    NARCIS (Netherlands)

    Weijerman, Mariska; Fulton, Elizabeth A.; Janssen, Annette B.G.; Kuiper, Jan J.; Leemans, Rik; Robson, Barbara J.; Leemput, Ingrid A. van de; Mooij, Wolf M.

    2015-01-01

    Despite the importance of coral reef ecosystems to the social and economic welfare of coastal communities, the condition of these marine ecosystems have generally degraded over the past decades. With an increased knowledge of coral reef ecosystem processes and a rise in computer power, dynamic model

  7. How models can support ecosystem-based management of coral reefs

    NARCIS (Netherlands)

    Weijerman, M.W.; Fulton, E.A.; Janssen, A.B.G.; Kuiper, J.J.; Leemans, R.; Leemput, van de I.A.; Mooij, W.M.

    2015-01-01

    Despite the importance of coral reef ecosystems to the social and economic welfare of coastal communities, the condition of these marine ecosystems have generally degraded over the past decades. With an increased knowledge of coral reef ecosystem processes and a rise in computer power, dynamic model

  8. Management strategy evaluation applied to coral reef ecosystems in support of ecosystem-based management

    NARCIS (Netherlands)

    Weijerman, M.; Fulton, Elizabeth A.; Brainard, Russell E.

    2016-01-01

    Ecosystem modelling is increasingly used to explore ecosystem-level effects of changing environmental conditions and management actions. For coral reefs there has been increasing interest in recent decades in the use of ecosystem models for evaluating the effects of fishing and the efficacy of ma

  9. Linking Terrigenous Sediment Delivery to Declines in Coral Reef Ecosystem Services

    Science.gov (United States)

    Worldwide coral reef conditions continue to decline despite the valuable socioeconomic benefits of these ecosystems. There is growing recognition that quantifying reefs in terms reflecting what stakeholders value is vital for comparing inherent tradeoffs among coastal management ...

  10. Linking Terrigenous Sediment Delivery to Declines in Coral Reef Ecosystem Services

    Science.gov (United States)

    Worldwide coral reef conditions continue to decline despite the valuable socioeconomic benefits of these ecosystems. There is growing recognition that quantifying reefs in terms reflecting what stakeholders value is vital for comparing inherent tradeoffs among coastal management ...

  11. Atlantis Modeled Output Data for the Coral Reef Ecosystems of Guam

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A proof-of-concept Guam Atlantis Coral Reef Ecosystem Model has been developed and an added coral module to the Atlantis framework has been validated. The model is...

  12. 50 CFR 665.620 - PRIA coral reef ecosystem fisheries. [Reserved

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false PRIA coral reef ecosystem fisheries. 665.620 Section 665.620 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND... Island Area Fisheries § 665.620 PRIA coral reef ecosystem fisheries. ...

  13. 50 CFR 665.220 - Hawaii coral reef ecosystem fisheries. [Reserved

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Hawaii coral reef ecosystem fisheries. 665.220 Section 665.220 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND... Fisheries § 665.220 Hawaii coral reef ecosystem fisheries. ...

  14. 50 CFR 665.420 - Mariana coral reef ecosystem fisheries. [Reserved

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Mariana coral reef ecosystem fisheries. 665.420 Section 665.420 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC... Mariana Archipelago Fisheries § 665.420 Mariana coral reef ecosystem fisheries. ...

  15. 50 CFR 665.120 - American Samoa coral reef ecosystem fisheries. [Reserved

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false American Samoa coral reef ecosystem fisheries. 665.120 Section 665.120 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL... PACIFIC American Samoa Fisheries § 665.120 American Samoa coral reef ecosystem fisheries....

  16. Management Strategy Evaluation Applied to Coral Reef Ecosystems in Support of Ecosystem-Based Management.

    Science.gov (United States)

    Weijerman, Mariska; Fulton, Elizabeth A; Brainard, Russell E

    2016-01-01

    Ecosystem modelling is increasingly used to explore ecosystem-level effects of changing environmental conditions and management actions. For coral reefs there has been increasing interest in recent decades in the use of ecosystem models for evaluating the effects of fishing and the efficacy of marine protected areas. However, ecosystem models that integrate physical forcings, biogeochemical and ecological dynamics, and human induced perturbations are still underdeveloped. We applied an ecosystem model (Atlantis) to the coral reef ecosystem of Guam using a suite of management scenarios prioritized in consultation with local resource managers to review the effects of each scenario on performance measures related to the ecosystem, the reef-fish fishery (e.g., fish landings) and coral habitat. Comparing tradeoffs across the selected scenarios showed that each scenario performed best for at least one of the selected performance indicators. The integrated 'full regulation' scenario outperformed other scenarios with four out of the six performance metrics at the cost of reef-fish landings. This model application quantifies the socio-ecological costs and benefits of alternative management scenarios. When the effects of climate change were taken into account, several scenarios performed equally well, but none prevented a collapse in coral biomass over the next few decades assuming a business-as-usual greenhouse gas emissions scenario.

  17. Management Strategy Evaluation Applied to Coral Reef Ecosystems in Support of Ecosystem-Based Management.

    Directory of Open Access Journals (Sweden)

    Mariska Weijerman

    Full Text Available Ecosystem modelling is increasingly used to explore ecosystem-level effects of changing environmental conditions and management actions. For coral reefs there has been increasing interest in recent decades in the use of ecosystem models for evaluating the effects of fishing and the efficacy of marine protected areas. However, ecosystem models that integrate physical forcings, biogeochemical and ecological dynamics, and human induced perturbations are still underdeveloped. We applied an ecosystem model (Atlantis to the coral reef ecosystem of Guam using a suite of management scenarios prioritized in consultation with local resource managers to review the effects of each scenario on performance measures related to the ecosystem, the reef-fish fishery (e.g., fish landings and coral habitat. Comparing tradeoffs across the selected scenarios showed that each scenario performed best for at least one of the selected performance indicators. The integrated 'full regulation' scenario outperformed other scenarios with four out of the six performance metrics at the cost of reef-fish landings. This model application quantifies the socio-ecological costs and benefits of alternative management scenarios. When the effects of climate change were taken into account, several scenarios performed equally well, but none prevented a collapse in coral biomass over the next few decades assuming a business-as-usual greenhouse gas emissions scenario.

  18. Coral Reef Ecosystems under Climate Change and Ocean Acidification

    OpenAIRE

    Ove Hoegh-Guldberg; Poloczanska, Elvira S.; William Skirving; Sophie Dove

    2017-01-01

    Coral reefs are found in a wide range of environments, where they provide food and habitat to a large range of organisms as well as providing many other ecological goods and services. Warm-water coral reefs, for example, occupy shallow sunlit, warm, and alkaline waters in order to grow and calcify at the high rates necessary to build and maintain their calcium carbonate structures. At deeper locations (40–150 m), “mesophotic” (low light) coral reefs accumulate calcium carbonate at much lower ...

  19. An integrated ecosystem model for coral reef management where oceanography, ecology and socio-economics meet

    NARCIS (Netherlands)

    Weijerman, Mariska

    2015-01-01

    Widespread coral reef decline, including decline in reef fish populations upon which many coastal human populations depend, have led to phase-shifts from the coral-dominated systems, found desirable by humans, to algal-dominated systems that provide less ecosystem services, and the loss of functiona

  20. An integrated ecosystem model for coral reef management where oceanography, ecology and socio-economics meet

    NARCIS (Netherlands)

    Weijerman, M.

    2015-01-01

    Summary Widespread coral reef decline, including decline in reef fish populations upon which many coastal human populations depend, have led to phase-shifts from the coral-dominated systems, found desirable by humans, to algal-dominated systems that provide less ecosystem services,

  1. An integrated ecosystem model for coral reef management where oceanography, ecology and socio-economics meet

    NARCIS (Netherlands)

    Weijerman, Mariska

    2015-01-01

    Widespread coral reef decline, including decline in reef fish populations upon which many coastal human populations depend, have led to phase-shifts from the coral-dominated systems, found desirable by humans, to algal-dominated systems that provide less ecosystem services, and the loss of

  2. An integrated ecosystem model for coral reef management where oceanography, ecology and socio-economics meet

    NARCIS (Netherlands)

    Weijerman, M.

    2015-01-01

    Summary Widespread coral reef decline, including decline in reef fish populations upon which many coastal human populations depend, have led to phase-shifts from the coral-dominated systems, found desirable by humans, to algal-dominated systems that provide less ecosystem services,

  3. An integrated ecosystem model for coral reef management where oceanography, ecology and socio-economics meet

    NARCIS (Netherlands)

    Weijerman, Mariska

    2015-01-01

    Widespread coral reef decline, including decline in reef fish populations upon which many coastal human populations depend, have led to phase-shifts from the coral-dominated systems, found desirable by humans, to algal-dominated systems that provide less ecosystem services, and the loss of functiona

  4. Functional Valuation of Ecosystem Services on Bonaire: an ecological analysis of ecosystem functions provided by coral reefs

    NARCIS (Netherlands)

    Beek, van I.J.M.

    2011-01-01

    This research is a semi-quantitative analysis of the functional value of coral reef habitats on Bonaire to support ecosystem services. It is part of an economic valuation study of marine and terrestrial ecosystem services on Bonaire.

  5. Functional Valuation of Ecosystem Services on Bonaire: an ecological analysis of ecosystem functions provided by coral reefs

    NARCIS (Netherlands)

    Beek, van I.J.M.

    2011-01-01

    This research is a semi-quantitative analysis of the functional value of coral reef habitats on Bonaire to support ecosystem services. It is part of an economic valuation study of marine and terrestrial ecosystem services on Bonaire.

  6. Clues to Coral Reef Ecosystem Health: Spectral Analysis Coupled with Radiative Transfer Modeling

    Science.gov (United States)

    Guild, L.; Ganapol, B.; Kramer, P.; Armstrong, R.; Gleason, A.; Torres, J.; Johnson, L.; Garfield, N.

    2003-12-01

    Coral reefs are among the world's most productive and biologically rich ecosystems and are some of the oldest ecosystems on Earth. Coralline structures protect coastlines from storms, maintain high diversity of marine life, and provide nurseries for marine species. Coral reefs play a role in carbon cycling through high rates of organic carbon metabolism and calcification. Coral reefs provide fisheries habitat that are the sole protein source for humans on remote islands. Reefs respond immediately to environmental change and therefore are considered "canaries" of the oceans. However, the world's reefs are in peril: they have shrunk 10-50% from their historical extent due to climate change and anthropogenic activity. An important contribution to coral reef research is improved spectral distinction of reef species' health where anthropogenic activity and climate change impacts are high. Relatively little is known concerning the spectral properties of coral or how coral structures reflect and transmit light. New insights into optical processes of corals under stressed conditions can lead to improved interpretation of airborne and satellite data and forecasting of immediate or long-term impacts of events such as bleaching and disease in coral. We are investigating the spatial and spectral resolution required to detect remotely changes in reef health by coupling spectral analysis of in situ spectra and airborne spectral data with a new radiative transfer model called CorMOD2. Challenges include light attenuation by the water column, atmospheric scattering, and scattering caused by the coral themselves that confound the spectral signal. In CorMOD2, input coral reflectance measurements produce modeled absorption through an inversion at each visible wavelength. The first model development phase of CorMOD2 imposes a scattering baseline that is constant regardless of coral condition, and further specifies that coral is optically thick. Evolution of CorMOD2 is towards a coral

  7. Critical research needs for identifying future changes in Gulf coral reef ecosystems

    Science.gov (United States)

    Feary, David A.; Burt, John A.; Bauman, Andrew G.; Al Hazeem, Shaker; Abdel-Moati, Mohamed A.; Al-Khalifa, Khalifa A.; Anderson, Donald M.; Amos, Carl; Baker, Andrew; Bartholomew, Aaron; Bento, Rita; Cavalcante, Geórgenes H.; Chen, Chaolun Allen; Coles, Steve L.; Dab, Koosha; Fowler, Ashley M.; George, David; Grandcourt, Edwin; Hill, Ross; John, David M.; Jones, David A.; Keshavmurthy, Shashank; Mahmoud, Huda; Moradi Och Tapeh, Mahdi; Mostafavi, Pargol Ghavam; Naser, Humood; Pichon, Michel; Purkis, Sam; Riegl, Bernhard; Samimi-Namin, Kaveh; Sheppard, Charles; Vajed Samiei, Jahangir; Voolstra, Christian R.; Wiedenmann, Joerg

    2014-01-01

    Expert opinion was assessed to identify current knowledge gaps in determining future changes in Arabian/ Persian Gulf (thereafter ‘Gulf’) coral reefs. Thirty-one participants submitted 71 research questions that were peer-assessed in terms of scientific importance (i.e., filled a knowledge gap and was a research priority) and efficiency in resource use (i.e., was highly feasible and ecologically broad). Ten research questions, in six major research areas, were highly important for both understanding Gulf coral reef ecosystems and also an efficient use of limited research resources. These questions mirrored global evaluations of the importance of understanding and evaluating biodiversity, determining the potential impacts of climate change, the role of anthropogenic impacts in structuring coral reef communities, and economically evaluating coral reef communities. These questions provide guidance for future research on coral reef ecosystems within the Gulf, and enhance the potential for assessment and management of future changes in this globally significant region. PMID:23643407

  8. Critical research needs for identifying future changes in Gulf coral reef ecosystems

    KAUST Repository

    Feary, David A.

    2013-07-01

    Expert opinion was assessed to identify current knowledge gaps in determining future changes in Arabian/Persian Gulf (thereafter \\'Gulf\\') coral reefs. Thirty-one participants submitted 71 research questions that were peer-assessed in terms of scientific importance (i.e., filled a knowledge gap and was a research priority) and efficiency in resource use (i.e., was highly feasible and ecologically broad). Ten research questions, in six major research areas, were highly important for both understanding Gulf coral reef ecosystems and also an efficient use of limited research resources. These questions mirrored global evaluations of the importance of understanding and evaluating biodiversity, determining the potential impacts of climate change, the role of anthropogenic impacts in structuring coral reef communities, and economically evaluating coral reef communities. These questions provide guidance for future research on coral reef ecosystems within the Gulf, and enhance the potential for assessment and management of future changes in this globally significant region. © 2013 Elsevier Ltd.

  9. Critical research needs for identifying future changes in Gulf coral reef ecosystems.

    Science.gov (United States)

    Feary, David A; Burt, John A; Bauman, Andrew G; Al Hazeem, Shaker; Abdel-Moati, Mohamed A; Al-Khalifa, Khalifa A; Anderson, Donald M; Amos, Carl; Baker, Andrew; Bartholomew, Aaron; Bento, Rita; Cavalcante, Geórgenes H; Chen, Chaolun Allen; Coles, Steve L; Dab, Koosha; Fowler, Ashley M; George, David; Grandcourt, Edwin; Hill, Ross; John, David M; Jones, David A; Keshavmurthy, Shashank; Mahmoud, Huda; Moradi Och Tapeh, Mahdi; Mostafavi, Pargol Ghavam; Naser, Humood; Pichon, Michel; Purkis, Sam; Riegl, Bernhard; Samimi-Namin, Kaveh; Sheppard, Charles; Vajed Samiei, Jahangir; Voolstra, Christian R; Wiedenmann, Joerg

    2013-07-30

    Expert opinion was assessed to identify current knowledge gaps in determining future changes in Arabian/Persian Gulf (thereafter 'Gulf') coral reefs. Thirty-one participants submitted 71 research questions that were peer-assessed in terms of scientific importance (i.e., filled a knowledge gap and was a research priority) and efficiency in resource use (i.e., was highly feasible and ecologically broad). Ten research questions, in six major research areas, were highly important for both understanding Gulf coral reef ecosystems and also an efficient use of limited research resources. These questions mirrored global evaluations of the importance of understanding and evaluating biodiversity, determining the potential impacts of climate change, the role of anthropogenic impacts in structuring coral reef communities, and economically evaluating coral reef communities. These questions provide guidance for future research on coral reef ecosystems within the Gulf, and enhance the potential for assessment and management of future changes in this globally significant region.

  10. Fungi and their role in corals and coral reef ecosystems

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Ravindran, J.

    to colourful, hard and soft corals, sponges, a diverse population of fishes, holothurians, calciferous algae and other myriad communities (Connell 1978). They support tourism, food production and coastal protection from natural hazards. Corals fall in two... in the French Polynesia (Golubic et al. 2005). Bak and Laane (1987) observed a dark mycelial fungus with perithecia, probably belonging to Ascomycetes in black bands of Porites species in the eastern part of the Indonesian Archipelago. Partial dissolution...

  11. Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems

    NARCIS (Netherlands)

    Rix, L.; de Goeij, J.M.; Mueller, C.E.; Struck, U.; Middelburg, J.J.; van Duyl, F.C.; Al-Horani, F.A.; Wild, C.; Naumann, M.S.; van Oevelen, D.

    2016-01-01

    Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and

  12. Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems

    NARCIS (Netherlands)

    Rix, L.; de Goeij, J.M.; Mueller, C.E.; Struck, U.; Middelburg, J.J.; van Duyl, F.C.; Al-Horani, F.A.; Wild, C.; Naumann, M.S.; Van Oevelen, D.

    2016-01-01

    Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrient

  13. Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems

    NARCIS (Netherlands)

    Rix, L.; de Goeij, J.M.; Mueller, C.E.; Struck, U.; Middelburg, J.J.; van Duyl, F.C.; Al-Horani, F.A.; Wild, C.; Naumann, M.S.; Van Oevelen, D.

    2016-01-01

    Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrient

  14. EFFECTS OF GLOBAL CHANGE ON CORAL REEF ECOSYSTEMS

    Science.gov (United States)

    Corals and coral reefs of the Caribbean and through the world are deteriorating at an accelerated rate. Several stressors are believed to contrbute to this decline, including global changes in atmospheric gases and land use patterns. In particular, warmer water temperatures and...

  15. EFFECTS OF GLOBAL CHANGE ON CORAL REEF ECOSYSTEMS

    Science.gov (United States)

    Corals and coral reefs of the Caribbean and through the world are deteriorating at an accelerated rate. Several stressors are believed to contrbute to this decline, including global changes in atmospheric gases and land use patterns. In particular, warmer water temperatures and...

  16. Human activity selectively impacts the ecosystem roles of parrotfishes on coral reefs

    KAUST Repository

    Bellwood, David R.

    2011-11-16

    Around the globe, coral reefs and other marine ecosystems are increasingly overfished. Conventionally, studies of fishing impacts have focused on the population size and dynamics of targeted stocks rather than the broader ecosystem-wide effects of harvesting. Using parrotfishes as an example, we show how coral reef fish populations respond to escalating fishing pressure across the Indian and Pacific Oceans. Based on these fish abundance data, we infer the potential impact on four key functional roles performed by parrotfishes. Rates of bioerosion and coral predation are highly sensitive to human activity, whereas grazing and sediment removal are resilient to fishing. Our results offer new insights into the vulnerability and resilience of coral reefs to the ever-growing human footprint. The depletion of fishes causes differential decline of key ecosystem functions, radically changing the dynamics of coral reefs and setting the stage for future ecological surprises. © 2011 The Royal Society.

  17. Climate warming, marine protected areas and the ocean-scale integrity of coral reef ecosystems

    OpenAIRE

    Graham, N. A. J.; Mcclanahan, T.R.; MacNeil, M. Aaron; Wilson, Shaun K.; Polunin, Nicholas; Jennings, Simon; Chabanet, Pascale; Clark, Susan; Spalding, Mark; Letourneur, Yves; Bigot, Lionel; Galzin, René; Öhman, Marcus C; Garpe, Kajsa C.; Edwards, Alasdair J.

    2008-01-01

    Coral reefs have emerged as one of the ecosystems most vulnerable to climate variation and change. While the contribution\\ud of a warming climate to the loss of live coral cover has been well documented across large spatial and temporal scales, the\\ud associated effects on fish have not. Here, we respond to recent and repeated calls to assess the importance of local\\ud management in conserving coral reefs in the context of global climate change. Such information is important, as coral reef\\ud...

  18. An Integrated Coral Reef Ecosystem Model to Support Resource Management under a Changing Climate.

    NARCIS (Netherlands)

    Weijerman, Mariska; Fulton, Elizabeth A.; Kaplan, Isaac C.; Gorton, Rebecca; Leemans, Rik; Mooij, W.M.; Brainard, Russell E.

    2015-01-01

    Millions of people rely on the ecosystem services provided by coral reefs, but sustaining these benefits requires an understanding of how reefs and their biotic communities are affected by local human-induced disturbances and global climate change. Ecosystem-based management that explicitly

  19. An Integrated Coral Reef Ecosystem Model to Support Resource Management under a Changing Climate

    NARCIS (Netherlands)

    Weijerman, Mariska; Fulton, Elizabeth A.; Kaplan, Isaac C.; Gorton, Rebecca; Leemans, R.; Mooij, W.M.; Brainard, Russell E.

    2015-01-01

    Millions of people rely on the ecosystem services provided by coral reefs, but sustaining these benefits requires an understanding of how reefs and their biotic communities are affected by local human-induced disturbances and global climate change. Ecosystem-based management that explicitly

  20. An Integrated Coral Reef Ecosystem Model to Support Resource Management under a Changing Climate.

    NARCIS (Netherlands)

    Weijerman, Mariska; Fulton, Elizabeth A.; Kaplan, Isaac C.; Gorton, Rebecca; Leemans, Rik; Mooij, W.M.; Brainard, Russell E.

    2015-01-01

    Millions of people rely on the ecosystem services provided by coral reefs, but sustaining these benefits requires an understanding of how reefs and their biotic communities are affected by local human-induced disturbances and global climate change. Ecosystem-based management that explicitly consider

  1. An Integrated Coral Reef Ecosystem Model to Support Resource Management under a Changing Climate

    NARCIS (Netherlands)

    Weijerman, Mariska; Fulton, Elizabeth A.; Kaplan, Isaac C.; Gorton, Rebecca; Leemans, R.; Mooij, W.M.; Brainard, Russell E.

    2015-01-01

    Millions of people rely on the ecosystem services provided by coral reefs, but sustaining these benefits requires an understanding of how reefs and their biotic communities are affected by local human-induced disturbances and global climate change. Ecosystem-based management that explicitly consider

  2. Coral reef ecosystem decline: changing dynamics of coral reef carbonate production and implications for reef growth potential

    Science.gov (United States)

    Perry, Chris

    2016-04-01

    Global-scale deteriorations in coral reef health have caused major shifts in species composition and are likely to be exacerbated by climate change. It has been suggested that one effect of these ecological changes will be to lower reef carbonate production rates, which will impair reef growth potential and, ultimately, may lead to states of net reef erosion. However, quantitative data to support such assertions are limited, and linkages between the ecological state of coral reefs and their past and present geomorphic performance (in other words their growth potential) are poorly resolved. Using recently collected data from sites in the Caribbean and Indian Ocean, and which have undergone very different post-disturbance ecological trajectories over the last ~20-30 years, the differential impacts of disturbance on contemporary carbonate production regimes and on reef growth potential can be explored. In the Caribbean, a region which has been severely impacted ecological over the last 30+ years, our datasets show that average carbonate production rates on reefs are now less than 50% of pre-disturbance rates, and that calculated accretion rates (mm yr-1) are an about order of magnitude lower within shallow water habitats compared to Holocene averages. Collectively, these data suggest that recent ecological declines are now propagating through the system to impact on the geomorphic performance of Caribbean reefs and will impair their future growth potential. In contrast, the carbonate budgets of most reefs across the Chagos archipelago (central Indian Ocean), which is geographically remote and largely isolated from direct human disturbances, have recovered rapidly from major past disturbances (specifically the 1998 coral bleaching event). The carbonate budgets on these remote reefs now average +3.7 G (G = kg CaCO3 m-2 yr-1). Most significantly the production rates on Acropora-dominated reefs, which were most severely impacted by the 1998 bleaching event, average +8.4 G

  3. Integration of coral reef ecosystem process studies and remote sensing: Chapter 5

    Science.gov (United States)

    Brook, John; Yates, Kimberly; Halley, Robert

    2006-01-01

    Worldwide, local-scale anthropogenic stress combined with global climate change is driving shifts in the state of reef benthic communities from coral-rich to micro- or macroalgal-dominated (Knowlton, 1992; Done, 1999). Such phase shifts in reef benthic communities may be either abrupt or gradual, and case studies from diverse ocean basins demonstrate that recovery, while uncertain (Hughes, 1994), typically involves progression through successional stages (Done, 1992). These transitions in benthic community structure involve changes in community metabolism, and accordingly, the holistic evaluation of associated biogeochemical variables is of great intrinsic value (Done, 1992). Effective reef management requires advance prediction of coral reef alteration in the face of anthropogenic stress and change in the global environment (Hatcher, 1997a). In practice, this goal requires techniques that can rapidly discern, at an early stage, sublethal effects that may cause long-term increases in mortality (brown, 1988; Grigg and Dollar, 1990). Such methods would improve our understanding of the differences in the population, community, and ecosystem structure, as well as function, between pristine and degraded reefs. This knowledge base could then support scientifically based management strategies (Done, 1992). Brown (1988) noted the general lack of rigor in the assessment of stress on coral reefs and suggested that more quantitative approaches than currently exist are needed to allow objective understanding of coral reef dynamics. Sensitive techniques for the timely appraisal of pollution effects or generalized endemic stress in coral reefs are sorely lacking (Grigg and Dollar, 1990; Wilkinsin, 1992). Moreover, monitoring methods based on population inventories, sclerochronology, or reproductive biology tend to myopic and may give inconsistent results. Ideally, an improved means of evaluating reef stress would discriminate mortality due to natural causes from morality to

  4. Holocene aggradation of the Dry Tortugas coral reef ecosystem

    Science.gov (United States)

    Brock, J. C.; Palaseanu-Lovejoy, M.; Poore, R. Z.; Nayegandhi, A.; Wright, C. W.

    2010-12-01

    Radiometric age dating of reef cores acquired at the Dry Tortugas coral reef ecosystem (DTCRE) was merged with lidar topographic mapping to examine Holocene reef development linked to spatial variation in growth and erosion under the control of sea level. Analysis of variance of lidar topography confirmed the presence of three distinct terraces on all three major DTCRE banks (Loggerhead Bank, Garden Bank, and Pulaski Bank). Reef building on the middle terrace (T2) began atop Pleistocene edifices on Loggerhead Bank by 8.0 ka (thousands of years ago) and on Garden Bank by 7.2 ka at elevations of about -16.0 m and -11.9 m, respectively, relative to present mean sea level. Following this initiation at different elevations, T2 aggraded vertically on both banks at different rates during the early Holocene under foundering conditions until a highstand at 5.2 ka, resulting in a 2.21 m offset in present mean T2 elevation between these banks. Initiation of an upper terrace (T1) occurred on both Loggerhead Bank and Garden Bank in association with sea-level fall to a lowstand at near 4.8 ka. This upper terrace initiated on Garden Bank at about 5.0 ka and then grew upward at rate of 2.5 mm year-1 until approximately 3.8 ka. On Loggerhead Bank, the upper T1 terrace formed after 4.5 ka at a higher vertical aggradation rate of 4.1 mm year-1, but at a lower elevation than on Garden Bank. Terrace T1 aggraded on Loggerhead Bank below the elevation of lowstands during late Holocene sea-level oscillation, and consequently erosion on Loggerhead Bank was minimal and likely limited to the crest of the upper terrace. In contrast, after 3.8 ka terrace T1 on Garden Bank likely tracked sea level and consequently underwent erosion when sea level fell to second, third and fourth lowstands at 3.3, 1.1, and 0.3 ka.

  5. Holocene aggradation of the Dry Tortugas coral reef ecosystem

    Science.gov (United States)

    Brock, J.C.; Palaseanu-Lovejoy, M.; Poore, R.Z.; Nayegandhi, A.; Wright, C.W.

    2010-01-01

    Radiometric age dating of reef cores acquired at the Dry Tortugas coral reef ecosystem (DTCRE) was merged with lidar topographic mapping to examine Holocene reef development linked to spatial variation in growth and erosion under the control of sea level. Analysis of variance of lidar topography confirmed the presence of three distinct terraces on all three major DTCRE banks (Loggerhead Bank, Garden Bank, and Pulaski Bank). Reef building on the middle terrace (T2) began atop Pleistocene edifices on Loggerhead Bank by 8.0 ka (thousands of years ago) and on Garden Bank by 7.2 ka at elevations of about −16.0 m and −11.9 m, respectively, relative to present mean sea level. Following this initiation at different elevations, T2 aggraded vertically on both banks at different rates during the early Holocene under foundering conditions until a highstand at 5.2 ka, resulting in a 2.21 m offset in present mean T2 elevation between these banks. Initiation of an upper terrace (T1) occurred on both Loggerhead Bank and Garden Bank in association with sea-level fall to a lowstand at near 4.8 ka. This upper terrace initiated on Garden Bank at about 5.0 ka and then grew upward at rate of 2.5 mm year−1 until approximately 3.8 ka. On Loggerhead Bank, the upper T1 terrace formed after 4.5 ka at a higher vertical aggradation rate of 4.1 mm year−1, but at a lower elevation than on Garden Bank. Terrace T1 aggraded on Loggerhead Bank below the elevation of lowstands during late Holocene sea-level oscillation, and consequently erosion on Loggerhead Bank was minimal and likely limited to the crest of the upper terrace. In contrast, after 3.8 ka terrace T1 on Garden Bank likely tracked sea level and consequently underwent erosion when sea level fell to second, third and fourth lowstands at 3.3, 1.1, and 0.3 ka.

  6. Insights into the Coral Microbiome: Underpinning the Health and Resilience of Reef Ecosystems.

    Science.gov (United States)

    Bourne, David G; Morrow, Kathleen M; Webster, Nicole S

    2016-09-01

    Corals are fundamental ecosystem engineers, creating large, intricate reefs that support diverse and abundant marine life. At the core of a healthy coral animal is a dynamic relationship with microorganisms, including a mutually beneficial symbiosis with photosynthetic dinoflagellates (Symbiodinium spp.) and enduring partnerships with an array of bacterial, archaeal, fungal, protistan, and viral associates, collectively termed the coral holobiont. The combined genomes of this coral holobiont form a coral hologenome, and genomic interactions within the hologenome ultimately define the coral phenotype. Here we integrate contemporary scientific knowledge regarding the ecological, host-specific, and environmental forces shaping the diversity, specificity, and distribution of microbial symbionts within the coral holobiont, explore physiological pathways that contribute to holobiont fitness, and describe potential mechanisms for holobiont homeostasis. Understanding the role of the microbiome in coral resilience, acclimation, and environmental adaptation is a new frontier in reef science that will require large-scale collaborative research efforts.

  7. Towards an ecosystem-based approach of Guam's coral reefs

    NARCIS (Netherlands)

    Weijerman, M.; Grace-McCaskey, Cynthia; Grafeld, Shanna L.; Kotowicz, Dawn M.; Oleson, Kirsten L.L.; Putten, van Ingrid E.

    2016-01-01

    Management of tropical reef ecosystems under pressure from terrestrial and extractive marine activities is not straightforward, especially when the interests of extractive and non-extractive marine resource sectors compete. Before implementing management actions, potential outcomes of alternative

  8. Herbivory, connectivity, and ecosystem resilience: response of a coral reef to a large-scale perturbation.

    Directory of Open Access Journals (Sweden)

    Thomas C Adam

    Full Text Available Coral reefs world-wide are threatened by escalating local and global impacts, and some impacted reefs have shifted from coral dominance to a state dominated by macroalgae. Therefore, there is a growing need to understand the processes that affect the capacity of these ecosystems to return to coral dominance following disturbances, including those that prevent the establishment of persistent stands of macroalgae. Unlike many reefs in the Caribbean, over the last several decades, reefs around the Indo-Pacific island of Moorea, French Polynesia have consistently returned to coral dominance following major perturbations without shifting to a macroalgae-dominated state. Here, we present evidence of a rapid increase in populations of herbivorous fishes following the most recent perturbation, and show that grazing by these herbivores has prevented the establishment of macroalgae following near complete loss of coral on offshore reefs. Importantly, we found the positive response of herbivorous fishes to increased benthic primary productivity associated with coral loss was driven largely by parrotfishes that initially recruit to stable nursery habitat within the lagoons before moving to offshore reefs later in life. These results underscore the importance of connectivity between the lagoon and offshore reefs for preventing the establishment of macroalgae following disturbances, and indicate that protecting nearshore nursery habitat of herbivorous fishes is critical for maintaining reef resilience.

  9. Herbivory, connectivity, and ecosystem resilience: response of a coral reef to a large-scale perturbation.

    Science.gov (United States)

    Adam, Thomas C; Schmitt, Russell J; Holbrook, Sally J; Brooks, Andrew J; Edmunds, Peter J; Carpenter, Robert C; Bernardi, Giacomo

    2011-01-01

    Coral reefs world-wide are threatened by escalating local and global impacts, and some impacted reefs have shifted from coral dominance to a state dominated by macroalgae. Therefore, there is a growing need to understand the processes that affect the capacity of these ecosystems to return to coral dominance following disturbances, including those that prevent the establishment of persistent stands of macroalgae. Unlike many reefs in the Caribbean, over the last several decades, reefs around the Indo-Pacific island of Moorea, French Polynesia have consistently returned to coral dominance following major perturbations without shifting to a macroalgae-dominated state. Here, we present evidence of a rapid increase in populations of herbivorous fishes following the most recent perturbation, and show that grazing by these herbivores has prevented the establishment of macroalgae following near complete loss of coral on offshore reefs. Importantly, we found the positive response of herbivorous fishes to increased benthic primary productivity associated with coral loss was driven largely by parrotfishes that initially recruit to stable nursery habitat within the lagoons before moving to offshore reefs later in life. These results underscore the importance of connectivity between the lagoon and offshore reefs for preventing the establishment of macroalgae following disturbances, and indicate that protecting nearshore nursery habitat of herbivorous fishes is critical for maintaining reef resilience.

  10. Resource-Fish surveys using timed-swims at 14 coral reef ecosystem sites of West Hawaii in 2005, (NODC Accession 0002627)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Effective management of coral reef ecosystems depends on adequate data on the status and trends of key ecosystem components. In spite of which, previous coral reef...

  11. Resource-Fish surveys using timed-swims at 14 coral reef ecosystem sites off West Hawaii and 39 sites off Maui in 2005 (NODC Accession 0002709)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Effective management of coral reef ecosystems depends on adequate data on the status and trends of key ecosystem components. In spite of which, previous coral reef...

  12. Resource-fish surveys using timed-swims at 14 coral reef ecosystem sites off West Hawaii and 39 sites off Maui in 2005 (NODC Accession 0002709)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Effective management of coral reef ecosystems depends on adequate data on the status and trends of key ecosystem components. In spite of which, previous coral reef...

  13. Resource-fish surveys using timed-swims at fourteen coral reef ecosystem sites of West Hawaii in 2005 (NODC Accession 0002627)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Effective management of coral reef ecosystems depends on adequate data on the status and trends of key ecosystem components. In spite of which, previous coral reef...

  14. Climate warming, marine protected areas and the ocean-scale integrity of coral reef ecosystems.

    Directory of Open Access Journals (Sweden)

    Nicholas A J Graham

    Full Text Available Coral reefs have emerged as one of the ecosystems most vulnerable to climate variation and change. While the contribution of a warming climate to the loss of live coral cover has been well documented across large spatial and temporal scales, the associated effects on fish have not. Here, we respond to recent and repeated calls to assess the importance of local management in conserving coral reefs in the context of global climate change. Such information is important, as coral reef fish assemblages are the most species dense vertebrate communities on earth, contributing critical ecosystem functions and providing crucial ecosystem services to human societies in tropical countries. Our assessment of the impacts of the 1998 mass bleaching event on coral cover, reef structural complexity, and reef associated fishes spans 7 countries, 66 sites and 26 degrees of latitude in the Indian Ocean. Using Bayesian meta-analysis we show that changes in the size structure, diversity and trophic composition of the reef fish community have followed coral declines. Although the ocean scale integrity of these coral reef ecosystems has been lost, it is positive to see the effects are spatially variable at multiple scales, with impacts and vulnerability affected by geography but not management regime. Existing no-take marine protected areas still support high biomass of fish, however they had no positive affect on the ecosystem response to large-scale disturbance. This suggests a need for future conservation and management efforts to identify and protect regional refugia, which should be integrated into existing management frameworks and combined with policies to improve system-wide resilience to climate variation and change.

  15. [A review of the role and function of microbes in coral reef ecosystem].

    Science.gov (United States)

    Zhou, Jin; Jin, Hui; Cai, Zhong-Hua

    2014-03-01

    Coral reef is consisted with several kinds of reef-associated organisms, including coral, fish, benthos, algae and microbes, which is an important marine ecosystem. Coral reef lives in the oligotrophic environment, has very highly primary productivity and net productivity, and is called "tropical rain forest in ocean". In corals, diverse microorganisms exert a significant influence on biogeochemical and ecological processes, including food webs, organism life cycles, and nutrient cycling. With the development of molecular biology, the role of microorganisms in a coral system is becoming more outstanding. In this article, we reviewed current understanding on 1) the onset of coral-bacterial associations; 2) the characteristics of microbes in coral (specificity, plasticity and co-evolution) ; 3) the role and signal regulation of microbes in the health and disease of coral; and 4) the response mechanism of microbes for global climatic change and consequent effects, such as temperature rise, ocean acidification and eutrophication. The aims of this article were to summarize the latest theories and achievements, clear the mechanism of microbial ecology in coral reefs and provide a theoretical reference for better protection and maintaining the coral's biodiversity.

  16. An assessment of global warming stress on Caribbean coral reef ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, D.K.; Hendec, J.C.; Mendez, A. (NOAA, Miami, FL (USA). Atlantic Oceanography and Meteorology Laboratory)

    1992-07-01

    There is evidence that stress on coral reef ecosystems in the Caribbean region is increasing. Recently numerous authors have stated that the major stress results from 'abnormally high' seasonal sea surface temperatures (SST) and have implicated global warming as a cause, stating that recent episodes of coral bleaching result therefrom. However, an analysis of available SST data sets shows no discernible warming trend that could cause an increase in coral bleaching. Given the lack of long-term records synoptic with observations of coral ecosystem health, there is insufficient evidence available to label temperatures observed in coincidence with recent regional bleaching events as 'abnormally' high.

  17. Ecosystem-scale effects of aragonite saturation, temperature, and nutrients on coral-reef calcification

    Science.gov (United States)

    Silverman, J.; Caldeira, K.; Lazar, B.; Erez, J.

    2008-12-01

    We investigated the relations between net calcification of an entire coral reef in the northern Red Sea and annual changes in aragonite saturation, temperature, and nutrient loading over a two year period, and augmented this study with similar observations in the Great Barrier Reef, Australia. In the Red Sea, average calcification rates varied between 60 ± 20 and 30 ± 20 mmol m-2 d-1 in the summer and winter, respectively. These changes primarily reflected seasonal differences in aragonite saturation and temperature. Data for the Great Barrier Reef are still being processed. Calcification rates at the ecosystem scale correlated remarkably well with the kinetics observed in inorganic aragonite precipitation experiments. This is a remarkable finding considering that calcification in coral reefs is primarily a biogenic process; this finding is yet to be explained mechanistically. These relationships are also in agreement with most laboratory studies on individual stony corals and coral mesocosms. The consistency of these responses at levels ranging from inorganic kinetics through the ecosystem scale suggests that these relationships are sufficiently robust to make predictions of coral reef response to ocean acidification and global warming. Finally, in a number of nighttime measurements, we observed net aragonite dissolution despite the supersaturated state of overlying reef water. This apparent dissolution is most likely biologically mediated. Aragonite dissolution, combined with decreasing aragonite precipitation, suggests that at least some reefs will be undergoing net dissolution by the time atmospheric carbon dioxide concentration doubles over its pre- industrial value.

  18. Challenges for Ecosystem Services Provided by Coral Reefs In the Face of Climate Change

    Science.gov (United States)

    Kikuchi, R. K.; Elliff, C. I.

    2014-12-01

    Coral reefs provide many ecosystem services of which coastal populations are especially dependent upon, both in cases of extreme events and in daily life. However, adaptation to climate change is still relatively unknown territory regarding the ecosystem services provided by coastal environments, such as coral reefs. Management strategies usually consider climate change as a distant issue and rarely include ecosystem services in decision-making. Coral reefs are among the most vulnerable environments to climate change, considering the impact that increased ocean temperature and acidity have on the organisms that compose this ecosystem. If no actions are taken, the most likely scenario to occur will be of extreme decline in the ecosystem services provided by coral reefs. Loss of biodiversity due to the pressures of ocean warming and acidification will lead to increased price of seafood products, negative impact on food security, and ecological imbalances. Also, sea-level rise and fragile structures due to carbonate dissolution will increase vulnerability to storms, which can lead to shoreline erosion and ultimately threaten coastal communities. Both these conditions will undoubtedly affect recreation and tourism, which are often the most important use values in the case of coral reef systems. Adaptation strategies to climate change must take on an ecosystem-based approach with continuous monitoring programs, so that multiple ecosystem services are considered and not only retrospective trends are analyzed. Brazilian coral reefs have been monitored on a regular basis since 2000 and, considering that these marginal coral reefs of the eastern Atlantic are naturally under stressful conditions (e.g. high sedimentation rates), inshore reefs of Brazil, such as those in Tinharé-Boipeba, have shown lower vitality rates due to greater impacts from the proximity to the coastal area (e.g. pollution, overfishing, sediment run-off). This chronic negative impact must be addressed

  19. Divergence of seafloor elevation and sea level rise in coral reef ecosystems

    Science.gov (United States)

    Yates, Kimberly K.; Zawada, David G.; Smiley, Nathan A.; Tiling-Range, Ginger

    2017-01-01

    Coral reefs serve as natural barriers that protect adjacent shorelines from coastal hazards such as storms, waves, and erosion. Projections indicate global degradation of coral reefs due to anthropogenic impacts and climate change will cause a transition to net erosion by mid-century. Here, we provide a comprehensive assessment of the combined effect of all of the processes affecting seafloor accretion and erosion by measuring changes in seafloor elevation and volume for five coral reef ecosystems in the Atlantic, Pacific, and Caribbean over the last several decades. Regional-scale mean elevation and volume losses were observed at all five study sites and in 77 % of the 60 individual habitats that we examined across all study sites. Mean seafloor elevation losses for whole coral reef ecosystems in our study ranged from −0.09 to −0.8 m, corresponding to net volume losses ranging from 3.4  ×  106 to 80.5  ×  106 m3 for all study sites. Erosion of both coral-dominated substrate and non-coral substrate suggests that the current rate of carbonate production is no longer sufficient to support net accretion of coral reefs or adjacent habitats. We show that regional-scale loss of seafloor elevation and volume has accelerated the rate of relative sea level rise in these regions. Current water depths have increased to levels not predicted until near the year 2100, placing these ecosystems and nearby communities at elevated and accelerating risk to coastal hazards. Our results set a new baseline for projecting future impacts to coastal communities resulting from degradation of coral reef systems and associated losses of natural and socioeconomic resources.

  20. Impacts of human activities on coral reef ecosystems of southern Taiwan: a long-term study.

    Science.gov (United States)

    Liu, Pi-Jen; Meng, Pei-Jie; Liu, Li-Lian; Wang, Jih-Terng; Leu, Ming-Yih

    2012-06-01

    In July 2001, the National Museum of Marine Biology and Aquarium, co-sponsored by the Kenting National Park Headquarters and Taiwan's National Science Council, launched a Long-Term Ecological Research (LTER) program to monitor anthropogenic impacts on the ecosystems of southern Taiwan, specifically the coral reefs of Kenting National Park (KNP), which are facing an increasing amount of anthropogenic pressure. We found that the seawater of the reef flats along Nanwan Bay, Taiwan's southernmost embayment, was polluted by sewage discharge at certain monitoring stations. Furthermore, the consequently higher nutrient and suspended sediment levels had led to algal blooms and sediment smothering of shallow water corals at some sampling sites. Finally, our results show that, in addition to this influx of anthropogenically-derived sewage, increasing tourist numbers are correlated with decreasing shallow water coral cover, highlighting the urgency of a more proactive management plan for KNP's coral reefs. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Critical thresholds and tangible targets for ecosystem-based management of coral reef fisheries.

    Science.gov (United States)

    McClanahan, Tim R; Graham, Nicholas A J; MacNeil, M Aaron; Muthiga, Nyawira A; Cinner, Joshua E; Bruggemann, J Henrich; Wilson, Shaun K

    2011-10-11

    Sustainably managing ecosystems is challenging, especially for complex systems such as coral reefs. This study develops critical reference points for sustainable management by using a large empirical dataset on the coral reefs of the western Indian Ocean to investigate associations between levels of target fish biomass (as an indicator of fishing intensity) and eight metrics of ecosystem state. These eight ecological metrics each exhibited specific thresholds along a continuum of fishable biomass ranging from heavily fished sites to old fisheries closures. Three thresholds lay above and five below a hypothesized window of fishable biomass expected to produce a maximum multispecies sustainable yield (B(MMSY)). Evaluating three management systems in nine countries, we found that unregulated fisheries often operate below the B(MMSY), whereas fisheries closures and, less frequently, gear-restricted fisheries were within or above this window. These findings provide tangible management targets for multispecies coral reef fisheries and highlight key tradeoffs required to achieve different fisheries and conservation goals.

  2. Environmental quality and preservation; reefs, corals, and carbonate sands; guides to reef-ecosystem health and environment

    Science.gov (United States)

    Lidz, Barbara H.

    2001-01-01

    Introduction In recent years, the health of the entire coral reef ecosystem that lines the outer shelf off the Florida Keys has declined markedly. In particular, loss of those coral species that are the building blocks of solid reef framework has significant negative implications for economic vitality of the region. What are the reasons for this decline? Is it due to natural change, or are human activities (recreational diving, ship groundings, farmland runoff, nutrient influx, air-borne contaminants, groundwater pollutants) a contributing factor and if so, to what extent? At risk of loss are biologic resources of the reefs, including habitats for endangered species in shoreline mangroves, productive marine and wetland nurseries, and economic fisheries. A healthy reef ecosystem builds a protective offshore barrier to catastrophic wave action and storm surges generated by tropical storms and hurricanes. In turn, a healthy reef protects the homes, marinas, and infrastructure on the Florida Keys that have been designed to capture a lucrative tourism industry. A healthy reef ecosystem also protects inland agricultural and livestock areas of South Florida whose produce and meat feed much of the United States and other parts of the world. In cooperation with the National Oceanic and Atmospheric Administration's (NOAA) National Marine Sanctuary Program, the U.S. Geological Survey (USGS) continues longterm investigations of factors that may affect Florida's reefs. One of the first steps in distinguishing between natural change and the effects of human activities, however, is to determine how coral reefs have responded to past environmental change, before the advent of man. By so doing, accurate scientific information becomes available for Marine Sanctuary management to understand natural change and thus to assess and regulate potential human impact better. The USGS studies described here evaluate the distribution (location) and historic vitality (thickness) of Holocene

  3. Reef-Scale Thermal Stress Monitoring of Coral Ecosystems: New 5-km Global Products from NOAA Coral Reef Watch

    Directory of Open Access Journals (Sweden)

    Gang Liu

    2014-11-01

    Full Text Available The U.S. National Oceanic and Atmospheric Administration (NOAA Coral Reef Watch (CRW program has developed a daily global 5-km product suite based on satellite observations to monitor thermal stress on coral reefs. These products fulfill requests from coral reef managers and researchers for higher resolution products by taking advantage of new satellites, sensors and algorithms. Improvements of the 5-km products over CRW’s heritage global 50-km products are derived from: (1 the higher resolution and greater data density of NOAA’s next-generation operational daily global 5-km geo-polar blended sea surface temperature (SST analysis; and (2 implementation of a new SST climatology derived from the Pathfinder SST climate data record. The new products increase near-shore coverage and now allow direct monitoring of 95% of coral reefs and significantly reduce data gaps caused by cloud cover. The 5-km product suite includes SST Anomaly, Coral Bleaching HotSpots, Degree Heating Weeks and Bleaching Alert Area, matching existing CRW products. When compared with the 50-km products and in situ bleaching observations for 2013–2014, the 5-km products identified known thermal stress events and matched bleaching observations. These near reef-scale products significantly advance the ability of coral reef researchers and managers to monitor coral thermal stress in near-real-time.

  4. Anticipative management for coral reef ecosystem services in the 21st century.

    Science.gov (United States)

    Rogers, Alice; Harborne, Alastair R; Brown, Christopher J; Bozec, Yves-Marie; Castro, Carolina; Chollett, Iliana; Hock, Karlo; Knowland, Cheryl A; Marshell, Alyssa; Ortiz, Juan C; Razak, Tries; Roff, George; Samper-Villarreal, Jimena; Saunders, Megan I; Wolff, Nicholas H; Mumby, Peter J

    2015-02-01

    Under projections of global climate change and other stressors, significant changes in the ecology, structure and function of coral reefs are predicted. Current management strategies tend to look to the past to set goals, focusing on halting declines and restoring baseline conditions. Here, we explore a complementary approach to decision making that is based on the anticipation of future changes in ecosystem state, function and services. Reviewing the existing literature and utilizing a scenario planning approach, we explore how the structure of coral reef communities might change in the future in response to global climate change and overfishing. We incorporate uncertainties in our predictions by considering heterogeneity in reef types in relation to structural complexity and primary productivity. We examine 14 ecosystem services provided by reefs, and rate their sensitivity to a range of future scenarios and management options. Our predictions suggest that the efficacy of management is highly dependent on biophysical characteristics and reef state. Reserves are currently widely used and are predicted to remain effective for reefs with high structural complexity. However, when complexity is lost, maximizing service provision requires a broader portfolio of management approaches, including the provision of artificial complexity, coral restoration, fish aggregation devices and herbivore management. Increased use of such management tools will require capacity building and technique refinement and we therefore conclude that diversification of our management toolbox should be considered urgently to prepare for the challenges of managing reefs into the 21st century. © 2014 John Wiley & Sons Ltd.

  5. Cold-water coral ecosystem (Tisler Reef, Norwegian Shelf) may be a hotspot for carbon cycling

    NARCIS (Netherlands)

    White, M.; Wolff, G.A.; Lundälv, T.; Guihen, D.; Kiriakoulakis, K.; Lavaleye, M.; Duineveld, G.

    2012-01-01

    Cold-water coral (CWC) reefs are recognised as an important marine benthic eco system at continental margins. Where abundant, they most likely play a role both in the maintenance of biodiversity and in the provision of ecosystem services provided by shelf seas. Here, we directly measure the

  6. Species diversity of Polychaete in coral reef ecosystem of Great Nicobar Island, India

    Directory of Open Access Journals (Sweden)

    V. SEKAR

    2016-01-01

    Full Text Available Abstract. Sekar V Rajasekaran R, Sachithanandam V, Sankar R, Sridhar R, Kingsley PW. 2016. Species diversity of Polychaete in coral reef ecosystem of Great Nicobar Island, India. Nusantara Bioscience 8: 71-76. Crypto fauna inhabiting the shelves of the coral reefs in Great Nicobar Islands are affected by bio-erosion caused by grazing and boring of organisms, hence present study revealed on two major components the opportunistic and true borers. Samples were collected from four stations from three different coral types (live coral, highly degraded & rubble of the Great Nicobar Islands. Of the total 401 individuals of Polychaetes collected from various sites 8 taxonomic species namely Terebella ehrenbergi, Idanthyrsus pennatus, Lysidice ninetta, L. collaris, Pseudonereis variegata, Perinereis cultrifera, P. nigropunctata, Eurythoe complanata were identified from the aforementioned three coral type sources. Among these P. variegata and L. collaris which accounted for 32.01% and 28.5% respectively, were the most dominant cryptic groups; whereas I. pennatus and T. ehrenbergi were the least records in all three habitats which accounted for 1.75%. In this study, the observations revealed that degraded corals were found in greater abundance than rubble and live corals. The species composition was observed maximum in Laxmi Nagar due to the availability of degraded coral patches than other stations. The study to evaluates the baseline knowledge of the coral inhabiting Polychaete distribution, it would be a pathway for forthcoming researchers on particular group taxonomy, and towards better understanding & utilization of coral reef ecosystem of the Great Nicobar Islands.

  7. Coral Ecosystem Resilience, Conservation and Management on the Reefs of Jamaica in the Face of Anthropogenic Activities and Climate Change

    Directory of Open Access Journals (Sweden)

    M. James C. Crabbe

    2010-06-01

    Full Text Available Knowledge of factors that are important in reef resilience and integrity help us understand how reef ecosystems react following major anthropogenic and environmental disturbances. The North Jamaican fringing reefs have shown some recent resilience to acute disturbances from hurricanes and bleaching, in addition to the recurring chronic stressors of over-fishing and land development. Factors that can improve coral reef resilience are reviewed, and reef rugosity is shown to correlate with coral cover and growth, particularly for branching Acropora species. The biodiversity index for the Jamaican reefs was lowered after the 2005 mass bleaching event, as were the numbers of coral colonies, but both had recovered by 2009. The importance of coastal zone reef management strategies and the economic value of reefs are discussed, and a protocol is suggested for future management of Jamaican reefs.

  8. Evaluating the attractiveness and effectiveness of artificial coral reefs as a recreational ecosystem service.

    Science.gov (United States)

    Belhassen, Yaniv; Rousseau, Meghan; Tynyakov, Jenny; Shashar, Nadav

    2017-12-01

    Artificial reefs are increasingly being used around the globe to attract recreational divers, for both environmental and commercial reasons. This paper examines artificial coral reefs as recreational ecosystem services (RES) by evaluating their attractiveness and effectiveness and by examining divers' attitudes toward them. An online survey targeted at divers in Israel (n = 263) indicated that 35% of the dives in Eilat (a resort city on the shore of the Red Sea) take place at artificial reefs. A second study monitored divers' behavior around the Tamar artificial reef, one of the most popular submerged artificial reefs in Eilat, and juxtaposed it with divers' activities around two adjacent natural reefs. Findings show that the average diver density at the artificial reef was higher than at the two nearby natural knolls and that the artificial reef effectively diverts divers from natural knolls. A third study that examined the attitudes towards natural vs. artificial reefs found that the artificial reefs are considered more appropriate for training, but that divers feel less relaxed around them. By utilizing the RES approach as a framework, the study offers a comprehensive methodology that brings together the aesthetic, behavioral, and attitudinal aspects in terms of which artificial reefs can be evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. mkk_benthic_habitats - Benthic habitat of the coral reef ecosystem on the south shore of Molokai Hawaii.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A benthic habitat polygon coverage has been created of the coral reef ecosystem on the south shore of Moloka'i. Polygons were hand-digitized from visual...

  10. A predictive regression model for the geochemical variability of iron and manganese in a coral reef ecosystem

    Digital Repository Service at National Institute of Oceanography (India)

    Gopinath, A.; Kumar, N.C.; Jayalakshmy, K.V.; Padmalal, D.; Nair, S.M.

    microenvironments of coral reef ecosystem of Lakshadweep Archipelago. Positive correlations of Fe/Mn with nutrient forms attributes to a similar pattern of remineralization and depositional characteristics involved in their accumulation. Negative correlations...

  11. Monitoring of Coral Reef Ecosystems on Maui, Hawaii during 1989-1998 (NODC Accession 9900242)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In an effort to detect spatial and temporal changes in the structure of the coral reef community, coral coverage and reef fish density and diversity were documented...

  12. Monitoring of Coral Reef Ecosystems on Maui, Hawaii during 1989-1998 (NODC Accession 9900242)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In an effort to detect spatial and temporal changes in the structure of the coral reef community, coral coverage and reef fish density and diversity were documented...

  13. Lag effects in the impacts of mass coral bleaching on coral reef fish, fisheries, and ecosystems.

    Science.gov (United States)

    Graham, Nicholas A J; Wilson, Shaun K; Jennings, Simon; Polunin, Nicholas V C; Robinson, Jan; Bijoux, Jude P; Daw, Tim M

    2007-10-01

    Recent episodes of coral bleaching have led to wide-scale loss of reef corals and raised concerns over the effectiveness of existing conservation and management efforts. The 1998 bleaching event was most severe in the western Indian Ocean, where coral declined by up to 90% in some locations. Using fisheries-independent data, we assessed the long-term impacts of this event on fishery target species in the Seychelles, the overall size structure of the fish assemblage, and the effectiveness of two marine protected areas (MPAs) in protecting fish communities. The biomass of fished species above the size retained in fish traps changed little between 1994 and 2005, indicating no current effect on fishery yields. Biomass remained higher in MPAs, indicating they were effective in protecting fish stocks. Nevertheless, the size structure of the fish communities, as described with size-spectra analysis, changed in both fished areas and MPAs, with a decline in smaller fish (45 cm). We believe this represents a time-lag response to a reduction in reef structural complexity brought about because fishes are being lost through natural mortality and fishing, and are not being replaced by juveniles. This effect is expected to be greater in terms of fisheries productivity and, because congruent patterns are observed for herbivores, suggests that MPAs do not offer coral reefs long-term resilience to bleaching events. Corallivores and planktivores declined strikingly in abundance, particularly in MPAs, and this decline was associated with a similar pattern of decline in their preferred corals. We suggest that climate-mediated disturbances, such as coral bleaching, be at the fore of conservation planning for coral reefs.

  14. Climate-Smart Design for Ecosystem Management: A Test Application for Coral Reefs

    Science.gov (United States)

    West, Jordan M.; Courtney, Catherine A.; Hamilton, Anna T.; Parker, Britt A.; Julius, Susan H.; Hoffman, Jennie; Koltes, Karen H.; MacGowan, Petra

    2017-01-01

    The interactive and cumulative impacts of climate change on natural resources such as coral reefs present numerous challenges for conservation planning and management. Climate change adaptation is complex due to climate-stressor interactions across multiple spatial and temporal scales. This leaves decision makers worldwide faced with local, regional, and global-scale threats to ecosystem processes and services, occurring over time frames that require both near-term and long-term planning. Thus there is a need for structured approaches to adaptation planning that integrate existing methods for vulnerability assessment with design and evaluation of effective adaptation responses. The Corals and Climate Adaptation Planning project of the U.S. Coral Reef Task Force seeks to develop guidance for improving coral reef management through tailored application of a climate-smart approach. This approach is based on principles from a recently-published guide which provides a framework for adopting forward-looking goals, based on assessing vulnerabilities to climate change and applying a structured process to design effective adaptation strategies. Work presented in this paper includes: (1) examination of the climate-smart management cycle as it relates to coral reefs; (2) a compilation of adaptation strategies for coral reefs drawn from a comprehensive review of the literature; (3) in-depth demonstration of climate-smart design for place-based crafting of robust adaptation actions; and (4) feedback from stakeholders on the perceived usefulness of the approach. We conclude with a discussion of lessons-learned on integrating climate-smart design into real-world management planning processes and a call from stakeholders for an "adaptation design tool" that is now under development.

  15. Climate-Smart Design for Ecosystem Management: A Test Application for Coral Reefs.

    Science.gov (United States)

    West, Jordan M; Courtney, Catherine A; Hamilton, Anna T; Parker, Britt A; Julius, Susan H; Hoffman, Jennie; Koltes, Karen H; MacGowan, Petra

    2017-01-01

    The interactive and cumulative impacts of climate change on natural resources such as coral reefs present numerous challenges for conservation planning and management. Climate change adaptation is complex due to climate-stressor interactions across multiple spatial and temporal scales. This leaves decision makers worldwide faced with local, regional, and global-scale threats to ecosystem processes and services, occurring over time frames that require both near-term and long-term planning. Thus there is a need for structured approaches to adaptation planning that integrate existing methods for vulnerability assessment with design and evaluation of effective adaptation responses. The Corals and Climate Adaptation Planning project of the U.S. Coral Reef Task Force seeks to develop guidance for improving coral reef management through tailored application of a climate-smart approach. This approach is based on principles from a recently-published guide which provides a framework for adopting forward-looking goals, based on assessing vulnerabilities to climate change and applying a structured process to design effective adaptation strategies. Work presented in this paper includes: (1) examination of the climate-smart management cycle as it relates to coral reefs; (2) a compilation of adaptation strategies for coral reefs drawn from a comprehensive review of the literature; (3) in-depth demonstration of climate-smart design for place-based crafting of robust adaptation actions; and (4) feedback from stakeholders on the perceived usefulness of the approach. We conclude with a discussion of lessons-learned on integrating climate-smart design into real-world management planning processes and a call from stakeholders for an "adaptation design tool" that is now under development.

  16. An Integrated Coral Reef Ecosystem Model to Support Resource Management under a Changing Climate.

    Directory of Open Access Journals (Sweden)

    Mariska Weijerman

    Full Text Available Millions of people rely on the ecosystem services provided by coral reefs, but sustaining these benefits requires an understanding of how reefs and their biotic communities are affected by local human-induced disturbances and global climate change. Ecosystem-based management that explicitly considers the indirect and cumulative effects of multiple disturbances has been recommended and adopted in policies in many places around the globe. Ecosystem models give insight into complex reef dynamics and their responses to multiple disturbances and are useful tools to support planning and implementation of ecosystem-based management. We adapted the Atlantis Ecosystem Model to incorporate key dynamics for a coral reef ecosystem around Guam in the tropical western Pacific. We used this model to quantify the effects of predicted climate and ocean changes and current levels of current land-based sources of pollution (LBSP and fishing. We used the following six ecosystem metrics as indicators of ecosystem state, resilience and harvest potential: 1 ratio of calcifying to non-calcifying benthic groups, 2 trophic level of the community, 3 biomass of apex predators, 4 biomass of herbivorous fishes, 5 total biomass of living groups and 6 the end-to-start ratio of exploited fish groups. Simulation tests of the effects of each of the three drivers separately suggest that by mid-century climate change will have the largest overall effect on this suite of ecosystem metrics due to substantial negative effects on coral cover. The effects of fishing were also important, negatively influencing five out of the six metrics. Moreover, LBSP exacerbates this effect for all metrics but not quite as badly as would be expected under additive assumptions, although the magnitude of the effects of LBSP are sensitive to uncertainty associated with primary productivity. Over longer time spans (i.e., 65 year simulations, climate change impacts have a slight positive interaction with

  17. An Integrated Coral Reef Ecosystem Model to Support Resource Management under a Changing Climate.

    Science.gov (United States)

    Weijerman, Mariska; Fulton, Elizabeth A; Kaplan, Isaac C; Gorton, Rebecca; Leemans, Rik; Mooij, Wolf M; Brainard, Russell E

    2015-01-01

    Millions of people rely on the ecosystem services provided by coral reefs, but sustaining these benefits requires an understanding of how reefs and their biotic communities are affected by local human-induced disturbances and global climate change. Ecosystem-based management that explicitly considers the indirect and cumulative effects of multiple disturbances has been recommended and adopted in policies in many places around the globe. Ecosystem models give insight into complex reef dynamics and their responses to multiple disturbances and are useful tools to support planning and implementation of ecosystem-based management. We adapted the Atlantis Ecosystem Model to incorporate key dynamics for a coral reef ecosystem around Guam in the tropical western Pacific. We used this model to quantify the effects of predicted climate and ocean changes and current levels of current land-based sources of pollution (LBSP) and fishing. We used the following six ecosystem metrics as indicators of ecosystem state, resilience and harvest potential: 1) ratio of calcifying to non-calcifying benthic groups, 2) trophic level of the community, 3) biomass of apex predators, 4) biomass of herbivorous fishes, 5) total biomass of living groups and 6) the end-to-start ratio of exploited fish groups. Simulation tests of the effects of each of the three drivers separately suggest that by mid-century climate change will have the largest overall effect on this suite of ecosystem metrics due to substantial negative effects on coral cover. The effects of fishing were also important, negatively influencing five out of the six metrics. Moreover, LBSP exacerbates this effect for all metrics but not quite as badly as would be expected under additive assumptions, although the magnitude of the effects of LBSP are sensitive to uncertainty associated with primary productivity. Over longer time spans (i.e., 65 year simulations), climate change impacts have a slight positive interaction with other drivers

  18. A continuous, real-time water quality monitoring system for the coral reef ecosystems of Nanwan Bay, Southern Taiwan.

    Science.gov (United States)

    Tew, Kwee Siong; Leu, Ming-Yih; Wang, Jih-Terng; Chang, Chia-Ming; Chen, Chung-Chi; Meng, Pei-Jie

    2014-08-30

    The coral reef ecosystems of Nanwan Bay, Southern Taiwan are undergoing degradation due to anthropogenic impacts, and as such have resulted in a decline in coral cover. As a first step in preventing the continual degradation of these coral reef environments, it is important to understand how changes in water quality affect these ecosystems on a fine-tuned timescale. To this end, a real-time water quality monitoring system was implemented in Nanwan Bay in 2010. We found that natural events, such as cold water intrusion due to upwelling, tended to elicit temporal shifts in coral spawning between 2010 and 2011. In addition, Degree Heating Weeks (DHWs), a commonly utilized predictor of coral bleaching, were 0.92 and 0.59 in summer 2010 and 2011, respectively. Though this quantity of DHW was below the presumed stress-inducing value for these reefs, a rise in DHWs in the future may stress the resident corals.

  19. Coral reefs in the Anthropocene

    Science.gov (United States)

    Hughes, Terry P.; Barnes, Michele L.; Bellwood, David R.; Cinner, Joshua E.; Cumming, Graeme S.; Jackson, Jeremy B. C.; Kleypas, Joanie; van de Leemput, Ingrid A.; Lough, Janice M.; Morrison, Tiffany H.; Palumbi, Stephen R.; van Nes, Egbert H.; Scheffer, Marten

    2017-06-01

    Coral reefs support immense biodiversity and provide important ecosystem services to many millions of people. Yet reefs are degrading rapidly in response to numerous anthropogenic drivers. In the coming centuries, reefs will run the gauntlet of climate change, and rising temperatures will transform them into new configurations, unlike anything observed previously by humans. Returning reefs to past configurations is no longer an option. Instead, the global challenge is to steer reefs through the Anthropocene era in a way that maintains their biological functions. Successful navigation of this transition will require radical changes in the science, management and governance of coral reefs.

  20. Ocean acidification and coral reefs: effects on breakdown, dissolution, and net ecosystem calcification.

    Science.gov (United States)

    Andersson, Andreas J; Gledhill, Dwight

    2013-01-01

    The persistence of carbonate structures on coral reefs is essential in providing habitats for a large number of species and maintaining the extraordinary biodiversity associated with these ecosystems. As a consequence of ocean acidification (OA), the ability of marine calcifiers to produce calcium carbonate (CaCO(3)) and their rate of CaCO(3) production could decrease while rates of bioerosion and CaCO(3) dissolution could increase, resulting in a transition from a condition of net accretion to one of net erosion. This would have negative consequences for the role and function of coral reefs and the eco-services they provide to dependent human communities. In this article, we review estimates of bioerosion, CaCO(3) dissolution, and net ecosystem calcification (NEC) and how these processes will change in response to OA. Furthermore, we critically evaluate the observed relationships between NEC and seawater aragonite saturation state (Ω(a)). Finally, we propose that standardized NEC rates combined with observed changes in the ratios of dissolved inorganic carbon to total alkalinity owing to net reef metabolism may provide a biogeochemical tool to monitor the effects of OA in coral reef environments.

  1. Economic valuation of ecosystem services from coral reefs in the South Pacific: taking stock of recent experience.

    Science.gov (United States)

    Laurans, Yann; Pascal, Nicolas; Binet, Thomas; Brander, Luke; Clua, Eric; David, Gilbert; Rojat, Dominique; Seidl, Andrew

    2013-02-15

    The economic valuation of coral reefs ecosystem services is currently seen as a promising approach to demonstrate the benefits of sustainable management of coral ecosystems to policymakers and to provide useful information for improved decisions. Most coral reefs economic studies have been conducted in the United States, Southeast Asia and the Caribbean, and only a few have covered the South Pacific region. In this region, coral reefs are essential assets for small island developing states as well as for developed countries. Accordingly, a series of ecosystem services valuations has been carried out recently in the South Pacific, to try and supply decision-makers with new information. Applying ecosystem services valuation to the specific ecological, social, economic and cultural contexts of the South Pacific is however not straightforward. This paper analyses how extant valuations address the various management challenges of coral reef regions in general and more specifically for the South Pacific. Bearing in mind that economic valuation has to match policy-making contexts, we emphasize a series of specific considerations when conducting and applying ecosystem services valuation in South Pacific ecological and social contexts. Finally, the paper examines the decision-making situations in which extant valuations took place. We conclude that, although ecosystem valuations have been effectively used as a means to raise awareness with respect to coral reef conservation, methodologies will have to be further developed, with multidisciplinary inputs, if they are to provide valuable inputs in local and technical decision-making.

  2. Coral reef resilience through biodiversity

    Science.gov (United States)

    Rogers, Caroline S.

    2013-01-01

    Irrefutable evidence of coral reef degradation worldwide and increasing pressure from rising seawater temperatures and ocean acidification associated with climate change have led to a focus on reef resilience and a call to “manage” coral reefs for resilience. Ideally, global action to reduce emission of carbon dioxide and other greenhouse gases will be accompanied by local action. Effective management requires reduction of local stressors, identification of the characteristics of resilient reefs, and design of marine protected area networks that include potentially resilient reefs. Future research is needed on how stressors interact, on how climate change will affect corals, fish, and other reef organisms as well as overall biodiversity, and on basic ecological processes such as connectivity. Not all reef species and reefs will respond similarly to local and global stressors. Because reef-building corals and other organisms have some potential to adapt to environmental changes, coral reefs will likely persist in spite of the unprecedented combination of stressors currently affecting them. The biodiversity of coral reefs is the basis for their remarkable beauty and for the benefits they provide to society. The extraordinary complexity of these ecosystems makes it both more difficult to predict their future and more likely they will have a future.

  3. The origins of ambient biological sound from coral reef ecosystems in the Line Islands archipelago.

    Science.gov (United States)

    Freeman, Simon E; Rohwer, Forest L; D'Spain, Gerald L; Friedlander, Alan M; Gregg, Allison K; Sandin, Stuart A; Buckingham, Michael J

    2014-04-01

    Although ambient biological underwater sound was first characterized more than 60 years ago, attributing specific components of ambient sound to their creators remains a challenge. Noise produced by snapping shrimp typically dominates the ambient spectra near tropical coasts, but significant unexplained spectral variation exists. Here, evidence is presented indicating that a discernible contribution to the ambient sound field over coral reef ecosystems in the Line Islands archipelago originates from the interaction of hard-shelled benthic macro-organisms with the coral substrate. Recordings show a broad spectral peak centered between 14.30 and 14.63 kHz, incoherently added to a noise floor typically associated with relatively "white" snapping shrimp sounds. A 4.6 to 6.2 dB increase of pressure spectral density level in the 11 to 17 kHz band occurs simultaneously with an increase in benthic invertebrate activity at night, quantified through time-lapse underwater photography. Spectral-level-filtered recordings of hermit crabs Clibanarius diugeti in quiet aquarium conditions reveal that transient sounds produced by the interaction between the crustaceans' carapace, shell, and coral substrate are spectrally consistent with Line Islands recordings. Coral reef ecosystems are highly interconnected and subtle yet important ecological changes may be detected quantitatively through passive monitoring that utilizes the acoustic byproducts of biological activity.

  4. Future habitat suitability for coral reef ecosystems under global warming and ocean acidification.

    Science.gov (United States)

    Couce, Elena; Ridgwell, Andy; Hendy, Erica J

    2013-12-01

    Rising atmospheric CO2 concentrations are placing spatially divergent stresses on the world's tropical coral reefs through increasing ocean surface temperatures and ocean acidification. We show how these two stressors combine to alter the global habitat suitability for shallow coral reef ecosystems, using statistical Bioclimatic Envelope Models rather than basing projections on any a priori assumptions of physiological tolerances or fixed thresholds. We apply two different modeling approaches (Maximum Entropy and Boosted Regression Trees) with two levels of complexity (one a simplified and reduced environmental variable version of the other). Our models project a marked temperature-driven decline in habitat suitability for many of the most significant and bio-diverse tropical coral regions, particularly in the central Indo-Pacific. This is accompanied by a temperature-driven poleward range expansion of favorable conditions accelerating up to 40-70 km per decade by 2070. We find that ocean acidification is less influential for determining future habitat suitability than warming, and its deleterious effects are centered evenly in both hemispheres between 5° and 20° latitude. Contrary to expectations, the combined impact of ocean surface temperature rise and acidification leads to little, if any, degradation in future habitat suitability across much of the Atlantic and areas currently considered 'marginal' for tropical corals, such as the eastern Equatorial Pacific. These results are consistent with fossil evidence of range expansions during past warm periods. In addition, the simplified models are particularly sensitive to short-term temperature variations and their projections correlate well with reported locations of bleaching events. Our approach offers new insights into the relative impact of two global environmental pressures associated with rising atmospheric CO2 on potential future habitats, but greater understanding of past and current controls on coral

  5. Holocene key coral species in the Northwest Pacific: indicators of reef formation and reef ecosystem responses to global climate change and anthropogenic stresses in the near future

    Science.gov (United States)

    Hongo, Chuki

    2012-03-01

    The geological record of key coral species that contribute to reef formation and maintenance of reef ecosystems is important for understanding the ecosystem response to global-scale climate change and anthropogenic stresses in the near future. Future responses can be predicted from accumulated data on Holocene reef species identified in drillcore and from data on raised reef terraces. The present study analyzes a dataset based on 27 drillcores, raised reef terraces, and 134 radiocarbon and U-Th ages from reefs of the Northwest Pacific, with the aim of examining the role of key coral species in reef growth and maintenance for reef ecosystem during Holocene sea-level change. The results indicate a latitudinal change in key coral species: arborescent Acropora (Acropora intermedia and Acropora muricata) was the dominant reef builder at reef crests in the tropics, whereas Porites (Porites australiensis, Porites lutea, and Porites lobata) was the dominant contributor to reef growth in the subtropics between 10,000 and 7000 cal. years BP (when the rate of sea-level rise was 10 m/ka). Acropora digitifera, Acropora hyacinthus, Acropora robusta/A. abrotanoides, Isopora palifera, Favia stelligera, and Goniastrea retiformis from the corymbose and tabular Acropora facies were the main key coral species at reef crests between 7000 and 5000 cal. years BP (when the rate of sea-level rise was 5 m/ka) and during the following period of stable sea-level. Massive Porites (P. australiensis, P. lutea, and P. lobata) contributed to reef growth in shallow lagoons during the period of stable sea level. Key coral species from the corymbose and tabular Acropora facies have the potential to build reefs and maintain ecosystems in the near future under a global sea-level rise of 2-6 m/ka, as do key coral species from the arborescent Acropora facies and massive Porites facies, which show vigorous growth and are tolerant to relatively deep-water, low-energy environments. However, these species

  6. Community production modulates coral reef pH and the sensitivity of ecosystem calcification to ocean acidification

    Science.gov (United States)

    DeCarlo, Thomas M.; Cohen, Anne L.; Wong, George T. F.; Shiah, Fuh-Kwo; Lentz, Steven J.; Davis, Kristen A.; Shamberger, Kathryn E. F.; Lohmann, Pat

    2017-01-01

    Coral reefs are built of calcium carbonate (CaCO3) produced biogenically by a diversity of calcifying plants, animals, and microbes. As the ocean warms and acidifies, there is mounting concern that declining calcification rates could shift coral reef CaCO3 budgets from net accretion to net dissolution. We quantified net ecosystem calcification (NEC) and production (NEP) on Dongsha Atoll, northern South China Sea, over a 2 week period that included a transient bleaching event. Peak daytime pH on the wide, shallow reef flat during the nonbleaching period was ˜8.5, significantly elevated above that of the surrounding open ocean (˜8.0-8.1) as a consequence of daytime NEP (up to 112 mmol C m-2 h-1). Diurnal-averaged NEC was 390 ± 90 mmol CaCO3 m-2 d-1, higher than any other coral reef studied to date despite comparable calcifier cover (25%) and relatively high fleshy algal cover (19%). Coral bleaching linked to elevated temperatures significantly reduced daytime NEP by 29 mmol C m-2 h-1. pH on the reef flat declined by 0.2 units, causing a 40% reduction in NEC in the absence of pH changes in the surrounding open ocean. Our findings highlight the interactive relationship between carbonate chemistry of coral reef ecosystems and ecosystem production and calcification rates, which are in turn impacted by ocean warming. As open-ocean waters bathing coral reefs warm and acidify over the 21st century, the health and composition of reef benthic communities will play a major role in determining on-reef conditions that will in turn dictate the ecosystem response to climate change.

  7. Coral mucus functions as an energy carrier and particle trap in the reef ecosystem

    DEFF Research Database (Denmark)

    Wild, C.; Huettel, M.; Klueter, A.

    2004-01-01

    Zooxanthellae, endosymbiotic algae of reef-building corals, substantially contribute to the high gross primary production of coral reefs(1), but corals exude up to half of the carbon assimilated by their zooxanthellae as mucus(2,3). Here we show that released coral mucus efficiently traps organic...... matter from the water column and rapidly carries energy and nutrients to the reef lagoon sediment, which acts as a biocatalytic mineralizing filter. In the Great Barrier Reef, the dominant genus of hard corals, Acropora, exudes up to 4.8 litres of mucus per square metre of reef area per day. Between 56......% and 80% of this mucus dissolves in the reef water, which is filtered through the lagoon sands. Here, coral mucus is degraded at a turnover rate of at least 7% per hour. Detached undissolved mucus traps suspended particles, increasing its initial organic carbon and nitrogen content by three orders...

  8. Coral mucus functions as an energy carrier and particle trap in the reef ecosystem

    DEFF Research Database (Denmark)

    Wild, C.; Huettel, M.; Klueter, A.

    2004-01-01

    Zooxanthellae, endosymbiotic algae of reef-building corals, substantially contribute to the high gross primary production of coral reefs(1), but corals exude up to half of the carbon assimilated by their zooxanthellae as mucus(2,3). Here we show that released coral mucus efficiently traps organic...... matter from the water column and rapidly carries energy and nutrients to the reef lagoon sediment, which acts as a biocatalytic mineralizing filter. In the Great Barrier Reef, the dominant genus of hard corals, Acropora, exudes up to 4.8 litres of mucus per square metre of reef area per day. Between 56......% and 80% of this mucus dissolves in the reef water, which is filtered through the lagoon sands. Here, coral mucus is degraded at a turnover rate of at least 7% per hour. Detached undissolved mucus traps suspended particles, increasing its initial organic carbon and nitrogen content by three orders...

  9. Confronting the coral reef crisis

    Science.gov (United States)

    Bellwood, D. R.; Hughes, T. P.; Folke, C.; Nyström, M.

    2004-06-01

    The worldwide decline of coral reefs calls for an urgent reassessment of current management practices. Confronting large-scale crises requires a major scaling-up of management efforts based on an improved understanding of the ecological processes that underlie reef resilience. Managing for improved resilience, incorporating the role of human activity in shaping ecosystems, provides a basis for coping with uncertainty, future changes and ecological surprises. Here we review the ecological roles of critical functional groups (for both corals and reef fishes) that are fundamental to understanding resilience and avoiding phase shifts from coral dominance to less desirable, degraded ecosystems. We identify striking biogeographic differences in the species richness and composition of functional groups, which highlight the vulnerability of Caribbean reef ecosystems. These findings have profound implications for restoration of degraded reefs, management of fisheries, and the focus on marine protected areas and biodiversity hotspots as priorities for conservation.

  10. The Paradoxical Roles of Climate Stressors on Disturbance and Recovery of Coral Reef Ecosystems

    Science.gov (United States)

    Manfrino, C.; Foster, G.; Camp, E.

    2013-05-01

    The geographic isolation, absence of significant anthropogenic impacts, compressed spatial scale, and habitat diversity of Little Cayman combine to make it a natural laboratory for elucidating the dualistic impacts of various climatic events. These events both impart ecosystem disturbances and aid in the subsequent recovery of coral reef habitats. Within the isolated microcosm of Little Cayman the environmental factors commonly associated with coral stress, mortality, resilience and recovery hinted at by regional-scale observations can be more clearly observed. The primary thrust of this study is to reveal the under-pinning biophysical and hydrologic factors pertinent to reef resilience and to better understand the various roles played by climatic disturbances that have led to the rapid recovery of corals at Little Cayman following a spate of high temperature anomalies. Six closely-spaced high-temperature events were recorded in the Caribbean between the years of 1987 and 2009. Of these, only the 1998 global ENSO event, with well-documented levels of elevated SST, reduced cloud cover and surface water texture with concomittant increases in UV and irradiance and reduced water velocity, resulted in significant mortality at Little Cayman. Following this event, island-wide live coral cover decreased by 40%, from 26% to 14%. Annual monitoring of live coral cover following the 1998 ENSO event revealed no significant recovery of live coral cover until 2009, at which point there was a rapid rebound to pre-disturbance levels by 2011. Such a protracted step-change in coral recovery is indicative of one or more episodic events. The proposed scenario is that the numerous thermal stress events damaged the photo-system of the zooxanthellae, limiting the scope for growth and recovery as the metabolic budgets of corals were diverted to cellular repair. It is posited that the rapid cooling effect of frequent Tropical Storms and Hurricanes between 2002 - 2008, coupled with the

  11. Monitoring Watershed Water Quality Impacts on Near-Shore Coral Reef Ecosystems in American Samoa using NASA Earth Observations

    Science.gov (United States)

    Teaby, A.; Price, J.; Minovitz, D.; Makely, L.; Torres-Perez, J. L.; Schmidt, C.; Guild, L. S.; Palacios, S. L.

    2014-12-01

    Land use changes can greatly increase erosion and sediment loads reaching watersheds and downstream coastal waters. In coastal environments with steep terrain and small drainage basins, sedimentation directly influences water quality in near-shore marine environments. Poor water quality indicators (i.e., dissolved nutrients and high particulates) affect coral calcification, photosynthesis, and coral cover. The abundance, recruitment, and biodiversity of American Samoa's coral reefs have been heavily affected by population growth, land cover change, pollution, and sediment influx. Monitoring, managing, and protecting these fragile ecosystems remains difficult due to limited resource availability, steep terrain, and local land ownership. Despite extensive field hours, traditional field and lab-based water quality research produces temporally and spatially limited datasets. Using a 'ridge to reef' effort, this project built a management tool to assess coral reef vulnerability using land use, hydrology, water quality, and coral reef cover in American Samoa to provide local agencies and partners with spatial representation of water quality parameters and site-specific implications for coral reef vulnerability. This project used land cover classified from Landsat 7 and 8 images, precipitation data from NOAA, and physical ocean factors from Terra MODIS. Changes in land cover from 2000 to 2014 were also estimated using Landsat imagery. Final products were distributed to partners to enhance water quality management, community outreach, and coral reef conservation.

  12. Biology of corals and coral reefs

    Digital Repository Service at National Institute of Oceanography (India)

    Rajkumar, R.; Parulekar, A.H.

    This chapter deals with biology of corals, coral reefs (in general) and coral reefs of the Indian Ocean. Biology of corals is lucidly dealt with, beginning from the clarification on hermatypic and ahermatypic forms. A complete account...

  13. Ecosystem-Scale Effects of Nutrients and Fishing on Coral Reefs

    Directory of Open Access Journals (Sweden)

    Sheila M. Walsh

    2011-01-01

    Full Text Available Nutrient pollution and fishing are the primary local causes of coral reef decline but their ecosystem-scale effects are poorly understood. Results from small-scale manipulative experiments of herbivores and nutrients suggest prioritizing management of fishing over nutrient pollution because herbivores can control macroalgae and turf in the presence of nutrients. However, ecological theory suggests that the opposite occurs at large scales. Moreover, it is unclear whether fishing decreases herbivores because fishing of predators may result in an increase in herbivores. To investigate this paradox, data on the fish and benthic communities, fishing, and nutrients were collected on Kiritimati, Kiribati. Oceanographic conditions and a population resettlement program created a natural experiment to compare sites with different levels of fishing and nutrients. Contrary to theory, herbivores controlled macroalgae in the presence of nutrients at large spatial scales, and herbivores had greater effects on macroalgae when nutrients were higher. In addition, fishing did not increase herbivores. These results suggest that protecting herbivores may have greater relative benefits than reducing nutrient pollution, especially on polluted reefs. Reallocating fishing effort from herbivores to invertivores or planktivores may be one way to protect herbivores and indirectly maintain coral dominance on reefs impacted by fishing and nutrient pollution.

  14. Informing policy to protect coastal coral reefs: insight from a global review of reducing agricultural pollution to coastal ecosystems.

    Science.gov (United States)

    Kroon, Frederieke J; Schaffelke, Britta; Bartley, Rebecca

    2014-08-15

    The continuing degradation of coral reefs has serious consequences for the provision of ecosystem goods and services to local and regional communities. While climate change is considered the most serious risk to coral reefs, agricultural pollution threatens approximately 25% of the total global reef area with further increases in sediment and nutrient fluxes projected over the next 50 years. Here, we aim to inform coral reef management using insights learned from management examples that were successful in reducing agricultural pollution to coastal ecosystems. We identify multiple examples reporting reduced fluxes of sediment and nutrients at end-of-river, and associated declines in nutrient concentrations and algal biomass in receiving coastal waters. Based on the insights obtained, we recommend that future protection of coral reef ecosystems demands policy focused on desired ecosystem outcomes, targeted regulatory approaches, up-scaling of watershed management, and long-term maintenance of scientifically robust monitoring programs linked with adaptive management. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  15. Social, institutional, and knowledge mechanisms mediate diverse ecosystem service benefits from coral reefs.

    Science.gov (United States)

    Hicks, Christina C; Cinner, Joshua E

    2014-12-16

    Ecosystem services are supplied by nature but, by definition, are received by people. Ecosystem service assessments, intended to influence the decisions people make regarding their interactions with nature, need to understand how people benefit from different ecosystem services. A critical question is therefore, What determines the distribution of ecosystem service benefits between different sections of society? Here, we use an entitlements approach to examine how people perceive ecosystem service benefits across 28 coral reef fishing communities in four countries. In doing so, we quantitatively show that bundles of benefits are mediated by key access mechanisms (e.g., rights-based, economic, knowledge, social, and institutional). We find that specific access mechanisms influence which ecosystem services people prioritize. Social, institutional, and knowledge mechanisms are associated with the largest number and diversity of benefits. However, local context strongly determines whether specific access mechanisms enable or constrain benefits. Local ecological knowledge enabled people to prioritize a habitat benefit in Kenya, but constrained people from prioritizing the same benefit in Madagascar. Ecosystem service assessments, and their resultant policies, need to include the broad suite of access mechanisms that enable different people to benefit from a supply of ecosystem services.

  16. New perspectives on ecological mechanisms affecting coral recruitment on reefs

    NARCIS (Netherlands)

    Ritson-Williams, R.; Arnold, S.N.; Fogarty, N.D.; Steneck, R.S.; Vermeij, M.J.A.; Paul, V.J.

    2009-01-01

    Coral mortality has increased in recent decades, making coral recruitment more important than ever in sustaining coral reef ecosystems and contributing to their resilience. This review summarizes existing information on ecological factors affecting scleractinian coral recruitment. Successful recruit

  17. New perspectives on ecological mechanisms affecting coral recruitment on reefs

    NARCIS (Netherlands)

    Ritson-Williams, R.; Arnold, S.N.; Fogarty, N.D.; Steneck, R.S.; Vermeij, M.J.A.; Paul, V.J.

    2009-01-01

    Coral mortality has increased in recent decades, making coral recruitment more important than ever in sustaining coral reef ecosystems and contributing to their resilience. This review summarizes existing information on ecological factors affecting scleractinian coral recruitment. Successful

  18. Controls on Diel and Seasonal Aragonite Saturation State and Carbon Dioxide Variability in a Hawaiian Coral Reef Ecosystem

    Science.gov (United States)

    Shamberger, K. E.; Drupp, P.; Feely, R. A.; Sabine, C. L.; Solomon, R. F.; De Carlo, E. H.; Mackenzie, F. T.; Atkinson, M. J.

    2011-12-01

    The Coral Reef Instrumented Monitoring and CO2-Platform (CRIMP-CO2) was deployed in the southern Kaneohe Bay lagoon from December 2005 through May 2008, then on the Kaneohe Bay barrier reef from June 2008 to the present. The surface water temperature, partial pressure of carbon dioxide (pCO2sw), and aragonite saturation state (Ωarag) of barrier reef waters were similar to those in the southern bay lagoon on seasonal and annual time scales. The pCO2sw in Kaneohe Bay was higher in the summer than winter because temperature was also higher in summer. However, temperature and pCO2sw have opposing effects on Ωarag which resulted in a lack of seasonality in Ωarag. Deeper southern bay lagoon waters had attenuated diel cycles compared to the shallow and biogeochemically active barrier reef. Photosynthesis and respiration controlled the diel cycles of Ωarag and pCO2sw and resulted in large changes in both parameters on hourly time scales. The Ωarag levels in Kaneohe Bay were depressed, and pCO2sw levels elevated, compared to levels in the open ocean and in other coral reef systems because of high net ecosystem calcification (NEC) rates. NEC produced enough CO2 to maintain high pCO2sw levels while daily net photosynthesis consumed some CO2. As demonstrated for Kaneohe Bay, the biogeochemical cycles occurring in coral reef ecosystems strongly alter the Ωarag and pCO2sw of their open-ocean source waters. Taking into account the CO2 cycling within coral reef ecosystems may help determine which reefs will be negatively affected by ocean acidification in the near future.

  19. Community metabolism in shallow coral reef and seagrass ecosystems, lower Florida Keys

    Science.gov (United States)

    Turk, Daniela; Yates, Kimberly K.; Vega-Rodriguez, Maria; Toro-Farmer, Gerardo; L'Esperance, Chris; Melo, Nelson; Ramsewak, Deanesch; Estrada, S. Cerdeira; Muller-Karger, Frank E.; Herwitz, Stan R.; McGillis, Wade

    2016-01-01

    Diurnal variation of net community production (NEP) and net community calcification (NEC) were measured in coral reef and seagrass biomes during October 2012 in the lower Florida Keys using a mesocosm enclosure and the oxygen gradient flux technique. Seagrass and coral reef sites showed diurnal variations of NEP and NEC, with positive values at near-seafloor light levels >100–300 µEinstein m-2 s-1. During daylight hours, we detected an average NEP of 12.3 and 8.6 mmol O2 m-2 h-1 at the seagrass and coral reef site, respectively. At night, NEP at the seagrass site was relatively constant, while on the coral reef, net respiration was highest immediately after dusk and decreased during the rest of the night. At the seagrass site, NEC values ranged from 0.20 g CaCO3 m-2 h-1 during daylight to -0.15 g CaCO3 m-2 h-1 at night, and from 0.17 to -0.10 g CaCO3 m-2 h-1 at the coral reef site. There were no significant differences in pH and aragonite saturation states (Ωar) between the seagrass and coral reef sites. Decrease in light levels during thunderstorms significantly decreased NEP, transforming the system from net autotrophic to net heterotrophic.

  20. Palmyra Atoll coral reef habitat mapping completion report

    OpenAIRE

    2010-01-01

    The United States Coral Reef Task Force (USCRTF) was established in 1998 by Presidential Executive Order 13089 to lead U.S. efforts to preserve and protect coral reef ecosystems. Current, accurate, and consistent maps greatly enhance efforts to preserve and manage coral reef ecosystems. With comprehensive maps and habitat assessments, coral reef managers can be more effective in designing and implementing a variety of conservation measures, including: • Long-term monitoring programs with ...

  1. KAHO_BenthicHabitats - Benthic habitat of the coral reef ecosystem within and adjacent to Kaloko-Honokohau National Historical Park (KAHO) on the Kona Coast of Hawaii.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A benthic habitat polygon coverage has been created of the coral reef ecosystem within and adjacent to Kaloko-Honokohau National Historical Park (KAHO) on the Kona...

  2. PUHE_BenthicHabitats - Benthic habitat of the coral reef ecosystem off the coast of Puukohola Heiau (PUHE) National Historic Site on the Kona Coast of Hawaii.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A benthic habitat polygon coverage has been created of the coral reef ecosystem off the coast of Pu'ukohola Heiau (PUHE) National Historic Site on the Kona Coast of...

  3. PUHO_BenthicHabitats - Benthic habitat of the coral reef ecosystem off the coast of Puuhonua O Honaunau (PUHO) National Historical Park on the Kona Coast of Hawaii.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A benthic habitat polygon coverage has been created of the coral reef ecosystem off the coast of Pu'uhonua O Honaunau (PUHO) National Historical Park on the Kona...

  4. PUHO_BenthicHabitats - Benthic habitat of the coral reef ecosystem off the coast of Puuhonua O Honaunau (PUHO) National Historical Park on the Kona Coast of Hawaii.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A benthic habitat polygon coverage has been created of the coral reef ecosystem off the coast of Pu'uhonua O Honaunau (PUHO) National Historical Park on the Kona...

  5. Test of the Capability of Laser Line Scan Technology to Support Benthic Habitat Mapping in Coral Reef Ecosystems, Maui Island, November 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The utility of Laser Line Scan (LLS) Technology for optical validation of benthic habitat map data from coral reef ecosystems was tested with a deployment of a...

  6. PUHE_BenthicHabitats - Benthic habitat of the coral reef ecosystem off the coast of Puukohola Heiau (PUHE) National Historic Site on the Kona Coast of Hawaii.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A benthic habitat polygon coverage has been created of the coral reef ecosystem off the coast of Pu'ukohola Heiau (PUHE) National Historic Site on the Kona Coast of...

  7. Privately managed marine reserves as a mechanism for the conservation of coral reef ecosystems: a case study from Vietnam.

    Science.gov (United States)

    Svensson, Patrik; Rodwell, Lynda D; Attrill, Martin J

    2009-03-01

    Coral reef ecosystems have been declining at an alarming rate during recent decades, despite increasing numbers of marine protected areas (MPAs) encompassing coral reefs. However, many MPAs have not met reserve objectives, inhibiting effective protection. This study focuses on the potential effectiveness of a Hotel Managed Marine Reserve (HMMR) at enhancing reef fish stocks. Biannual visual fish census surveys were conducted at two marine reserves adjacent to Whale Island Resort, Vietnam, October 2005 to April 2007. The 6-year protected Whale Island Bay Reserve (11 ha) showed significantly higher fish densities, richness, average size, and number of fish >15 cm compared with two unprotected control sites. Fish stocks at a second newer reserve, Whale Island Bay Peninsula (5 ha), quickly increased after protection. This study has demonstrated the effectiveness of HMMRs, suggesting a global network of such privately managed reserves could play a part in the conservation of the world's coastal resources, while alleviating financial pressure on governments.

  8. Climate Change, Coral Reef Ecosystems, and Management Options for Marine Protected Areas

    Science.gov (United States)

    Keller, Brian D.; Gleason, Daniel F.; McLeod, Elizabeth; Woodley, Christa M.; Airamé, Satie; Causey, Billy D.; Friedlander, Alan M.; Grober-Dunsmore, Rikki; Johnson, Johanna E.; Miller, Steven L.; Steneck, Robert S.

    2009-12-01

    Marine protected areas (MPAs) provide place-based management of marine ecosystems through various degrees and types of protective actions. Habitats such as coral reefs are especially susceptible to degradation resulting from climate change, as evidenced by mass bleaching events over the past two decades. Marine ecosystems are being altered by direct effects of climate change including ocean warming, ocean acidification, rising sea level, changing circulation patterns, increasing severity of storms, and changing freshwater influxes. As impacts of climate change strengthen they may exacerbate effects of existing stressors and require new or modified management approaches; MPA networks are generally accepted as an improvement over individual MPAs to address multiple threats to the marine environment. While MPA networks are considered a potentially effective management approach for conserving marine biodiversity, they should be established in conjunction with other management strategies, such as fisheries regulations and reductions of nutrients and other forms of land-based pollution. Information about interactions between climate change and more “traditional” stressors is limited. MPA managers are faced with high levels of uncertainty about likely outcomes of management actions because climate change impacts have strong interactions with existing stressors, such as land-based sources of pollution, overfishing and destructive fishing practices, invasive species, and diseases. Management options include ameliorating existing stressors, protecting potentially resilient areas, developing networks of MPAs, and integrating climate change into MPA planning, management, and evaluation.

  9. Reefs for the future: Resilience of coral reefs in the main Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Declining health of coral reef ecosystems led scientists to search for factors that support reef resilience: the ability of reefs to resist and recover from...

  10. Climate change impacts on freshwater fish, coral reefs, and related ecosystem services in the United States

    Science.gov (United States)

    We analyzed the potential physical and economic impacts of climate change on freshwater fisheries and coral reefs in the United States, examining a reference scenario and two policy scenarios that limit global greenhouse gas (GHG) emissions. We modeled shifts in suitable habitat ...

  11. Degradation and recovery of Caribbean coral reefs

    OpenAIRE

    Paredes, Gustavo Adolfo

    2009-01-01

    Coral reef ecosystems worldwide have been seriously impacted by human activities. The current deteriorated state of coral reef communities is the result of a long history of exploitation. The scientific community has recognized the extent of degradation, its consequences, and how little we have done to avoid further degradation only in the last two decades. Marine reserves are one of the main conservation actions that could help to reduce the impacts of human activities on the ecosystem, part...

  12. Coral reefs in crisis.

    Science.gov (United States)

    Hinrichsen, D

    1997-01-01

    This article reports on the crisis facing reefs throughout the world and the struggle to save them. Coral reefs, one of the biological wonders of the world, are among the largest and oldest living communities of plants and animals on earth, having been evolved between 200 and 450 million years ago. Located mostly in the Pacific region, most established coral reefs are now dead and only the upper layer is covered by a thin changeable skin of living coral. Reefs, over the years, have been the main source of animal protein for over 1 billion people in Asia. Countries near the coastlines, which relied on the seas, have resorted to dynamite fishing, poisoning and other illegal and dangerous techniques. Overpopulation and pollution has caused the deteriorating conditions of the 600,000 sq. km of coral reefs worldwide. Despite these conditions, the government has ignored this problem as they struggle to develop their economies at the expense of common resources. In addition, this article narrates the efforts that are exerted by governments in promoting coral reef protection and management of these coastal resources, setting the Apo Island in the Philippines as an example of good management and sustainability.

  13. Coral reefs: Turning back time

    Science.gov (United States)

    Lough, Janice M.

    2016-03-01

    An in situ experiment finds that reducing the acidity of the seawater surrounding a natural coral reef significantly increases reef calcification, suggesting that ocean acidification may already be slowing coral growth. See Letter p.362

  14. Bleaching and stress in coral reef ecosystems: hsp70 expression by the giant barrel sponge Xestospongia muta.

    Science.gov (United States)

    López-Legentil, Susanna; Song, Bongkeun; McMurray, Steven E; Pawlik, Joseph R

    2008-04-01

    Sponges are a prominent component of coral reef ecosystems. Like reef-building corals, some sponges have been reported to bleach and die. The giant barrel sponge Xestospongia muta is one of the largest and most important components of Caribbean coral reef communities. Tissues of X. muta contain cyanobacterial symbionts of the Synechococcus group. Two types of bleaching have been described: cyclic bleaching, from which sponges recover, and fatal bleaching, which usually results in sponge death. We quantified hsp70 gene expression as an indicator of stress in X. muta undergoing cyclic and fatal bleaching and in response to thermal and salinity variability in both field and laboratory settings. Chlorophyll a content of sponge tissue was estimated to determine whether hsp70 expression was related to cyanobacterial abundance. We found that fatally bleached sponge tissue presented significantly higher hsp70 gene expression, but cyclically bleached tissue did not, yet both cyclic and fatally bleached tissues had lower chlorophyll a concentrations than nonbleached tissue. These results corroborate field observations suggesting that cyclic bleaching is a temporary, nonstressful state, while fatal bleaching causes significant levels of stress, leading to mortality. Our results support the hypothesis that Synechococcus symbionts are commensals that provide no clear advantage to their sponge host. In laboratory experiments, sponge pieces incubated at 30 degrees C exhibited significantly higher hsp70 expression than control pieces after 1.5 h, with sponge mortality after less than 15 h. In contrast, sponges at different salinities were not significantly stressed after the same period of time. Stress associated with increasing seawater temperatures may result in declining sponge populations in coral reef ecosystems.

  15. Are mesophotic coral ecosystems distinct communities and can they serve as refugia for shallow reefs?

    Science.gov (United States)

    Semmler, Robert F.; Hoot, Whitney C.; Reaka, Marjorie L.

    2017-06-01

    We analyzed an extensive dataset of over 9000 benthic and suprabenthic species found throughout the Gulf of Mexico (GoMx) to assess whether mesophotic coral ecosystems represent distinct assemblages and evaluate their potential to serve as refugia for shallow reef communities. We assessed community structure of the overall benthic community from 0 to 300 m via non-metric multidimensional scaling (NMDS) of species presence across depth bands. We used the Jaccard index of similarity to calculate the proportion of shared species between adjacent depth bands, measure species turnover with depth, and assess taxonomic overlap between shallow reefs versus progressively deeper depth bands. NMDS ordinations showed that the traditionally defined mesophotic range (30-150 m) as a whole is not a distinct community. In contrast, taxonomically distinct communities, determined by hierarchical clustering, were found at 0-70, 60-120, 110-200, and 190-300 m. Clustering highlighted an important separation in the benthic community at 60 m, which was especially important for actinopterygian fishes. Species turnover between adjacent depths decreased with depth for all taxa combined and individual taxa, with peaks at 60, 90-120, and 190-200 m. Fishes showed lower turnover from shallow to upper mesophotic depths (0-50 m) than all taxa combined, a substantial peak at 60 m, followed by a precipitous and continued decline in turnover thereafter. Taxonomic overlap between shallow (0-20 m) and progressively deeper zones declined steadily with depth in all taxa and individual taxa, suggesting that mid- and lower mesophotic habitats have less (but not inconsequential) potential to serve as refugia (60-150 m, 15-25% overlap with shallow habitats) than upper mesophotic zones (30-60 m, 30-45% overlap with shallow habitats) for all taxa combined. We conclude that the traditional mesophotic zone is home to three ecological communities in the GoMx, one that is confluent with shallow reefs, a distinct

  16. Population genetics of an ecosystem-defining reef coral Pocillopora damicornis in the Tropical Eastern Pacific.

    Directory of Open Access Journals (Sweden)

    David J Combosch

    Full Text Available BACKGROUND: Coral reefs in the Tropical Eastern Pacific (TEP are amongst the most peripheral and geographically isolated in the world. This isolation has shaped the biology of TEP organisms and lead to the formation of numerous endemic species. For example, the coral Pocillopora damicornis is a minor reef-builder elsewhere in the Indo-West Pacific, but is the dominant reef-building coral in the TEP, where it forms large, mono-specific stands, covering many hectares of reef. Moreover, TEP P. damicornis reproduces by broadcast spawning, while it broods mostly parthenogenetic larvae throughout the rest of the Indo-West Pacific. Population genetic surveys for P. damicornis from across its Indo-Pacific range indicate that gene flow (i.e. larval dispersal is generally limited over hundreds of kilometers or less. Little is known about the population genetic structure and the dispersal potential of P. damicornis in the TEP. METHODOLOGY: Using multilocus microsatellite data, we analyzed the population structure of TEP P. damicornis among and within nine reefs and test for significant genetic structure across three geographically and ecologically distinct regions in Panama. PRINCIPAL FINDINGS/CONCLUSIONS: We detected significant levels of population genetic structure (global R(ST = 0.162, indicating restricted gene flow (i.e. larvae dispersal, both among the three regions (R(RT = 0.081 as well as within regions (R(SR = 0.089. Limited gene flow across a distinct environmental cline, like the regional upwelling gradient in Panama, indicates a significant potential for differential adaptation and population differentiation. Individual reefs were characterized by unexpectedly high genet diversity (avg. 94%, relatively high inbreeding coefficients (global F(IS = 0.183, and localized spatial genetic structure among individuals (i.e. unique genets over 10 m intervals. These findings suggest that gene flow is limited in TEP P. damicornis

  17. Distribution and diversity of marine flora in coral reef ecosystems of Kadmat Island in Lakshadweep archipelago, Arabian Sea, India

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, V.V.; Komarpant, D.S.; Jagtap, T.G.

    is under constant threat of reclamation for cultivation of vegetables and dwellings. Poor composition, particularly of corals, indicated that the reefs around Kadmat Island were converting into algal or detrital reefs...

  18. Phytoplankton phenology indices in coral reef ecosystems: Application to ocean-color observations in the Red Sea

    KAUST Repository

    Racault, Marie-Fanny

    2015-02-18

    Phytoplankton, at the base of the marine food web, represent a fundamental food source in coral reef ecosystems. The timing (phenology) and magnitude of the phytoplankton biomass are major determinants of trophic interactions. The Red Sea is one of the warmest and most saline basins in the world, characterized by an arid tropical climate regulated by the monsoon. These extreme conditions are particularly challenging for marine life. Phytoplankton phenological indices provide objective and quantitative metrics to characterize phytoplankton seasonality. The indices i.e. timings of initiation, peak, termination and duration are estimated here using 15 years (1997–2012) of remote sensing ocean-color data from the European Space Agency (ESA) Climate Change Initiative project (OC-CCI) in the entire Red Sea basin. The OC-CCI product, comprising merged and bias-corrected observations from three independent ocean-color sensors (SeaWiFS, MODIS and MERIS), and processed using the POLYMER algorithm (MERIS period), shows a significant increase in chlorophyll data coverage, especially in the southern Red Sea during the months of summer NW monsoon. In open and reef-bound coastal waters, the performance of OC-CCI chlorophyll data is shown to be comparable with the performance of other standard chlorophyll products for the global oceans. These features have permitted us to investigate phytoplankton phenology in the entire Red Sea basin, and during both winter SE monsoon and summer NW monsoon periods. The phenological indices are estimated in the four open water provinces of the basin, and further examined at six coral reef complexes of particular socio-economic importance in the Red Sea, including Siyal Islands, Sharm El Sheikh, Al Wajh bank, Thuwal reefs, Al Lith reefs and Farasan Islands. Most of the open and deeper waters of the basin show an apparent higher chlorophyll concentration and longer duration of phytoplankton growth during the winter period (relative to the summer

  19. From ridge to reef—linking erosion and changing watersheds to impacts on the coral reef ecosystems of Hawai‘i and the Pacific Ocean

    Science.gov (United States)

    Stock, Jonathan D.; Cochran, Susan A.; Field, Michael E.; Jacobi, James D.; Tribble, Gordon

    2011-01-01

    Coral reef ecosystems are threatened by unprecedented watershed changes in the United States and worldwide. These ecosystems sustain fishing and tourism industries essential to the economic survival of many communities. Sediment, nutrients, and pollutants from watersheds are increasingly transported to coastal waters, where these contaminants damage corals. Although pollution from watersheds is one of many factors threatening coral survival, it is one that local people can have a profound influence on. U.S. Geological Survey scientists are using mapping, monitoring, and computer modeling to better forecast the effects of watershed changes on reef health. Working with communities in Hawai‘i and on other U.S. islands in the Pacific, they are helping to provide the science needed to make informed decisions on watershed and coral reef management.

  20. CORAL REEF BIOLOGICAL CRITERIA: USING THE CLEAN ...

    Science.gov (United States)

    Coral reefs are declining at unprecedented rates worldwide due to multiple interactive stressors including climate change and land-based sources of pollution. The Clean Water Act (CWA) can be a powerful legal instrument for protecting water resources, including the biological inhabitants of coral reefs. The objective of the CWA is to restore and maintain the chemical, physical and biological integrity of water resources. Coral reef protection and restoration under the Clean Water Act begins with water quality standards - provisions of state or Federal law that consist of a designated use(s) for the waters of the United States and water quality criteria sufficient to protect the uses. Aquatic life use is the designated use that is measured by biological criteria (biocriteria). Biocriteria are expectations set by a jurisdiction for the quality and quantity of living aquatic resources in a defined waterbody. Biocriteria are an important addition to existing management tools for coral reef ecosystems. The Technical Support Document “Coral Reef Biological Criteria: Using the Clean Water Act to Protect a National Treasure” will provide a framework to aid States and Territories in their development, adoption, and implementation of coral reef biocriteria in their respective water quality standards. The Technical Support Document “Coral Reef Biological Criteria: Using the Clean Water Act to Protect a National Treasure” will provide a framework for coral re

  1. Planktonic trophic structure in a coral reef ecosystem - Grazing versus microbial food webs and the production of mesozooplankton

    Science.gov (United States)

    Nakajima, Ryota; Yamazaki, Haruka; Lewis, Levi S.; Khen, Adi; Smith, Jennifer E.; Nakatomi, Nobuyuki; Kurihara, Haruko

    2017-08-01

    The relative contributions of grazing versus microbial food webs to the production of mesozooplankton communities in coral reef ecosystems remains an important and understudied field of inquiry. Here, we investigated the biomass and production of component organisms within these two food webs, and compared them to those of mesozooplankton on a coral reef in Okinawa, Japan throughout four seasons in 2011-2012. The relative production of grazing (phytoplankton) and microbial (nano and microzooplankton) food webs were on average 39% (7-77%) and 37% (19-57%), respectively, of the food requirements of particle-feeding mesozooplankton. Carbon flows within this planktonic food web suggested that primary production from the grazing food web could not satisfy the nutritional demands of mesozooplankton, and that the microbial food web contributed a significant amount of nutrition to their diets. These results also show that the heterotrophic components of the microbial food web (nano and microzooplankton) and mesozooplankton consume the equivalent of the entire phytoplankton production (particulate net production) each day, while the microzooplankton were almost entirely eaten by higher trophic levels (mesozooplankton) each day. However, even the combined production from both the grazing and microbial food webs did not fulfill mesozooplankton food requirements in some seasons, explaining 26-53%, suggesting that detritus was used to compensate for nutritional deficiencies during these periods. Understanding the flow of energy throughout coral reefs requires a detailed accounting of pelagic sources and sinks of carbon. Our results provide such an assessment and indicate that detailed investigation on the origin and production of detritus is necessary to better understand pelagic trophodynamics in coral ecosystems.

  2. 77 FR 48504 - Proposed Information Collection; Comment Request; Economic Value of Puerto Rico's Coral Reef...

    Science.gov (United States)

    2012-08-14

    ... Value of Puerto Rico's Coral Reef Ecosystems for Recreation-Tourism AGENCY: National Oceanic and... values of Puerto Rico's coral reef ecosystems. Estimates will be made for all ecosystem services for the Guanica Bay Watershed and for recreation-tourism for all of Puerto Rico's coral reef ecosystems. The...

  3. Coral reefs at risk

    Science.gov (United States)

    Showstack, Randy

    Eighty-eight percent of Southeast Asia's reefs are threatened by overfishing, destructive fishing, and sedimentation and pollution from inland activities, according to a new report by 35 regional scientists published by the World Resources Institute.Nearly 100,000 square kilometers of coral reefs—34% of the world's total—are located in Southeast Asia.

  4. Coral Reef Biological Criteria

    Science.gov (United States)

    Coral reefs worldwide are experiencing decline from a variety of stressors. Some important stressors are land-based sources of pollution and human activities in the coastal zone. However, few tools are available to offset the impact of these stressors. The Clean Water Act (CWA...

  5. Oman's coral reefs: A unique ecosystem challenged by natural and man-related stresses and in need of conservation.

    Science.gov (United States)

    Burt, J A; Coles, S; van Lavieren, H; Taylor, O; Looker, E; Samimi-Namin, K

    2016-04-30

    Oman contains diverse and abundant reef coral communities that extend along a coast that borders three environmentally distinct water bodies, with corals existing under unique and often stressful environmental conditions. In recent years Oman's reefs have undergone considerable change due to recurrent predatory starfish outbreaks, cyclone damage, harmful algal blooms, and other stressors. In this review we summarize current knowledge of the biology and status of corals in Oman, particularly in light of recent stressors and projected future threats, and examine current reef management practices. Oman's coral communities occur in marginal environmental conditions for reefs, and hence are quite vulnerable to anthropogenic effects. We recommend a focus on developing conservation-oriented coral research to guide proactive management and expansion of the number and size of designated protected areas in Oman, particularly those associated with critical coral habitat.

  6. Coral identity underpins architectural complexity on Caribbean reefs.

    Science.gov (United States)

    Alvarez-Filip, Lorenzo; Dulvy, Nicholas K; Côte, Isabelle M; Watkinson, Andrew R; Gill, Jennifer A

    2011-09-01

    The architectural complexity of ecosystems can greatly influence their capacity to support biodiversity and deliver ecosystem services. Understanding the components underlying this complexity can aid the development of effective strategies for ecosystem conservation. Caribbean coral reefs support and protect millions of livelihoods, but recent anthropogenic change is shifting communities toward reefs dominated by stress-resistant coral species, which are often less architecturally complex. With the regionwide decline in reef fish abundance, it is becoming increasingly important to understand changes in coral reef community structure and function. We quantify the influence of coral composition, diversity, and morpho-functional traits on the architectural complexity of reefs across 91 sites at Cozumel, Mexico. Although reef architectural complexity increases with coral cover and species richness, it is highest on sites that are low in taxonomic evenness and dominated by morpho-functionally important, reef-building coral genera, particularly Montastraea. Sites with similar coral community composition also tend to occur on reefs with very similar architectural complexity, suggesting that reef structure tends to be determined by the same key species across sites. Our findings provide support for prioritizing and protecting particular reef types, especially those dominated by key reef-building corals, in order to enhance reef complexity.

  7. The Global Coral Reef Crisis: Trends and Solutions (Coral Reefs: Values, Threats, and the Marine Aquarium Trade)

    Energy Technology Data Exchange (ETDEWEB)

    Shuman, Craig S. (Reef Check, UCLA)

    2003-02-05

    Second only to tropical rainforests, coral reefs support one of the world's most diverse natural habitats. Over 350 million individuals depend on coral reef resources for food and income. Unfortunately, the Earth is in the midst of a coral reef crisis. Anthropogenic impacts including overfishing, destructive fishing practices, sedimentation and pollution, as well as global climate change, have served to disrupt the natural processes that maintain the health of these ecosystems. Until recently, however, the global extent of the coral reef crisis was unknown. Reef Check was developed in 1996 as a volunteer, community-based monitoring protocol designed to measure the health of coral reefs on a global scale. With goals of education, monitoring, and management, Reef Check has activities in over 60 countries and territories. They have not only provided scientific evidence of the global extent of the coral reef crisis, but have provided the first community based steps to alleviate this urgent situation.

  8. Hawaii Institute for Marine Biology and NOAA National Ocean Service, Marine Sanctuary Program Partnership, in affiliation with the Coral Reef Assessment and Monitoring Program, 2007 Survey of the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve: Digital Still Images (NODC Accession 0052882)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Rapid Assessment Transects were conducted in 2007 in the Papahanaumokuakea Marine National Monument of the Northwest Hawaiian Islands Coral Reef Ecosystem Reserve....

  9. Hawaii Institute for Marine Biology and NOAA National Ocean Service, Marine Sanctuary Program Partnership, in affiliation with the Coral Reef Assessment and Monitoring Program, 2007 Survey of the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve: Benthic Data from Digital Still Images (NODC Accession 0000881)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Rapid Assessment Transects were conducted in 2007 in the Papahanaumokuakea Marine National Monument of the Northwest Hawaiian Islands Coral Reef Ecosystem Reserve....

  10. The Decline of Coral Reefs: a Political Economy Approach

    OpenAIRE

    Samuel, Asumadu-Sarkodie

    2015-01-01

    Coral reefs provide economic services like job, food and tourism. Yet, within the past decades, there has been an overwhelming decline in the vitality of coral reefs and their ecosystem. Scientist have not be able to set the record straight regarding their scientific argument on biodiversity and ecological wealth of natural environment. Therefore, actions to recover coral reefs from destruction have proved futile. This paper will analyze the economical values, economic valuation, socioeconomi...

  11. The influence of grain size, grain color, and suspended-sediment concentration on light attenuation: why fine-grained terrestrial sediment is bad for coral reef ecosystems

    Science.gov (United States)

    Storlazzi, Curt; Norris, Benjamin; Rosenberger, Kurt

    2015-01-01

    Sediment has been shown to be a major stressor to coral reefs globally. Although many researchers have tested the impact of sedimentation on coral reef ecosystems in both the laboratory and the field and some have measured the impact of suspended sediment on the photosynthetic response of corals, there has yet to be a detailed investigation on how properties of the sediment itself can affect light availability for photosynthesis. We show that finer-grained and darker-colored sediment at higher suspended-sediment concentrations attenuates photosynthetically active radiation (PAR) significantly more than coarser, lighter-colored sediment at lower concentrations and provide PAR attenuation coefficients for various grain sizes, colors, and suspended-sediment concentrations that are needed for biophysical modeling. Because finer-grained sediment particles settle more slowly and are more susceptible to resuspension, they remain in the water column longer, thus causing greater net impact by reducing light essential for photosynthesis over a greater duration. This indicates that coral reef monitoring studies investigating sediment impacts should concentrate on measuring fine-grained lateritic and volcanic soils, as opposed to coarser-grained siliceous and carbonate sediment. Similarly, coastal restoration efforts and engineering solutions addressing long-term coral reef ecosystem health should focus on preferentially retaining those fine-grained soils rather than coarse silt and sand particles.

  12. 76 FR 63904 - Proposed Information Collection; Comment Request; Coral Reef Conservation Program Administration

    Science.gov (United States)

    2011-10-14

    ..., extension 150, or Jenny.Waddell@noaagov. SUPPLEMENTARY INFORMATION: I. Abstract The Coral Reef Conservation... reef conservation to conduct activities to protect and conserve coral reef ecosystems. The information...) if a proposed project is consistent with the coral reef conservation priorities of authorities...

  13. Community Essay: Identifying management needs for sustainable coral-reef ecosystems

    Directory of Open Access Journals (Sweden)

    M. James Crabbe

    2009-04-01

    Full Text Available In 2007, I developed with the aid of the Earthwatch Institute and the Oak Foundation a capacity-building program in southern Belize to address issues of marine reserve management underpinned by science. The first component included group discussions on important issues related to the management of the reserves and review of scientific papers, strategic plans, and action plans. The second component included field research in the Sapodilla Cayes Marine Reserve and the Port Honduras Marine Reserve. The project’s overall objectives and outcomes were to increase the participants’ capacity to lead and educate regarding sustainable development and to promote networking among organizations that manage marine resources, enhancing their collective influence over policy decisions. From that program, the project group developed the concepts and management protocols for coral-reef sustainability elucidated below.

  14. Hydrology, plankton, and corals of the Maracajaú reefs (Northeastern Brazil: an ecosystem under severe thermal stress

    Directory of Open Access Journals (Sweden)

    Elga Miranda Mayal

    2009-06-01

    Full Text Available This study provides baseline information on the hydrological conditions and on the coral and plankton communities at the Maracajaú reef ecosystem (Northeastern Brazil. Studies were performed from February to June 2000, covering the transition from dry to rainy season. In this area, there is an offshore coral reef formation, where corals were observed in loco; the water samples were collected to obtain the hydrological and plankton data. Six scleractinian species were identified. Stable isotope analysis on the carbonate fraction of Favia gravida fragments showed that these corals were under severe thermal stress. Chlorophyll-a varied from 1.1 to 9.3 mg m-3, with higher values during the rainy season. Average zooplankton wet weight biomass were 117.0 (microzooplankton and 15.7 mg m -3(mesozooplankton. A total of 136 Phytoplankton and 61 zooplankton taxa were identified. Seasonal forcing determined the phyto-micro-and mesozooplankton community structure, rather than the coastal-offshore gradient.Esta pesquisa apresenta informações básicas sobre as condições hidrológicas e sobre as comunidades de corais e do plâncton no ecossistema recifal de Maracajaú (Nordeste do Brasil. Estudos foram realizados de fevereiro a junho de 2000, cobrindo o período de transição das estações seca a chuvosa. Nesta area existe uma formação de recife de coral afastada da costa, onde os corais foram observados in loco e amostras de água foram coletadas para a obtenção de dados hidrológicos e planctônicos. Foram identificadas seis espécies de escleractíneos. Análises com isótopos estáveis em fragmentos de carbonato de Favia gravida mostraram que este coral está sob estresse termal severo. As concentrações de clorofila-a variaram de 1,1 mg m-3 a 9,3 mg m-3, com maiores valores durante o período chuvoso. A biomassa média em peso úmido do zooplâncton foi de 117,0 mg m-3 para o microzooplâncton e de 15,7 mg m-3 para o mesozooplâncton. Foram

  15. Assessing the sensitivity of coral reef condition indicators to local and global stressors with Bayesian networks

    Science.gov (United States)

    Coral reefs are highly valued ecosystems that are currently imperiled. Although the value of coral reefs to human societies is only just being investigated and better understood, for many local and global economies coral reefs are important providers of ecosystem services that su...

  16. Assessing the sensitivity of coral reef condition indicators to local and global stressors with Bayesian networks

    Science.gov (United States)

    Coral reefs are highly valued ecosystems that are currently imperiled. Although the value of coral reefs to human societies is only just being investigated and better understood, for many local and global economies coral reefs are important providers of ecosystem services that su...

  17. Climate-driven coral reorganisation influences aggressive behaviour in juvenile coral-reef fishes

    Science.gov (United States)

    Kok, Judith E.; Graham, Nicholas A. J.; Hoogenboom, Mia O.

    2016-06-01

    Globally, habitat degradation is altering the abundance and diversity of species in a variety of ecosystems. This study aimed to determine how habitat degradation, in terms of changing coral composition under climate change, affected abundance, species richness and aggressive behaviour of juveniles of three damselfishes ( Pomacentrus moluccensis, P. amboinensis and Dischistodus perspicillatus, in order of decreasing reliance on coral). Patch reefs were constructed to simulate two types of reefs: present-day reefs that are vulnerable to climate-induced coral bleaching, and reefs with more bleaching-robust coral taxa, thereby simulating the likely future of coral reefs under a warming climate. Fish communities were allowed to establish naturally on the reefs during the summer recruitment period. Climate-robust reefs had lower total species richness of coral-reef fishes than climate-vulnerable reefs, but total fish abundance was not significantly different between reef types (pooled across all species and life-history stages). The nature of aggressive interactions, measured as the number of aggressive chases, varied according to coral composition; on climate-robust reefs, juveniles used the substratum less often to avoid aggression from competitors, and interspecific aggression became relatively more frequent than intraspecific aggression for juveniles of the coral-obligate P. moluccensis. This study highlights the importance of coral composition as a determinant of behaviour and diversity of coral-reef fishes.

  18. Coral Reef Ecosystem Data from the 2010-2011 Kahekili Herbivore Fisheries Management Area, West Maui, Herbivore Enhancement as a Tool for Reef Restoration Project (NODC Accession 0082869)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This research targets the Hawaii Coral Reef Initiative (HCRI) Priority Area A: Kahekili, Maui: Herbivore Fisheries Management Area (KHFMA). The project goal was to...

  19. 10th Anniversary Review: a changing climate for coral reefs.

    Science.gov (United States)

    Lough, Janice M

    2008-01-01

    Tropical coral reefs are charismatic ecosystems that house a significant proportion of the world's marine biodiversity. Their valuable goods and services are fundamental to the livelihood of large coastal populations in the tropics. The health of many of the world's coral reefs, and the goods and services they provide, have already been severely compromised, largely due to over-exploitation by a range of human activities. These local-scale impacts, with the appropriate government instruments, support and management actions, can potentially be controlled and even ameliorated. Unfortunately, other human actions (largely in countries outside of the tropics), by changing global climate, have added additional global-scale threats to the continued survival of present-day coral reefs. Moderate warming of the tropical oceans has already resulted in an increase in mass coral bleaching events, affecting nearly all of the world's coral reef regions. The frequency of these events will only increase as global temperatures continue to rise. Weakening of coral reef structures will be a more insidious effect of changing ocean chemistry, as the oceans absorb part of the excess atmospheric carbon dioxide. More intense tropical cyclones, changed atmospheric and ocean circulation patterns will all affect coral reef ecosystems and the many associated plants and animals. Coral reefs will not disappear but their appearance, structure and community make-up will radically change. Drastic greenhouse gas mitigation strategies are necessary to prevent the full consequences of human activities causing such alterations to coral reef ecosystems.

  20. Coral Reef Remote Sensing: Helping Managers Protect Reefs in a Changing Climate

    Science.gov (United States)

    Eakin, C.; Liu, G.; Li, J.; Muller-Karger, F. E.; Heron, S. F.; Gledhill, D. K.; Christensen, T.; Rauenzahn, J.; Morgan, J.; Parker, B. A.; Skirving, W. J.; Nim, C.; Burgess, T.; Strong, A. E.

    2010-12-01

    Climate change and ocean acidification are already having severe impacts on coral reef ecosystems. Warming oceans have caused corals to bleach, or expel their symbiotic algae (zooxanthellae) with alarming frequency and severity and have contributed to a rise in coral infectious diseases. Ocean acidification is reducing the availability of carbonate ions needed by corals and many other marine organisms to build structural components like skeletons and shells and may already be slowing the coral growth. These two impacts are already killing corals and slowing reef growth, reducing biodiversity and the structure needed to provide crucial ecosystem services. NOAA’s Coral Reef Watch (CRW) uses a combination of satellite data, in situ observations, and models to provide coral reef managers, scientists, and others with information needed to monitor threats to coral reefs. The advance notice provided by remote sensing and models allows resource managers to protect corals, coral reefs, and the services they provide, although managers often encounter barriers to implementation of adaptation strategies. This talk will focus on application of NOAA’s satellite and model-based tools that monitor the risk of mass coral bleaching on a global scale, ocean acidification in the Caribbean, and coral disease outbreaks in selected regions, as well as CRW work to train managers in their use, and barriers to taking action to adapt to climate change. As both anthropogenic CO2 and temperatures will continue to rise, local actions to protect reefs are becoming even more important.

  1. Acoustical Measurement and Biot Model for Coral Reef Detection and Quantification

    OpenAIRE

    Manik, Henry M.

    2016-01-01

    Coral reefs are coastal resources and very useful for marine ecosystems. Nowadays, the existence of coral reefs is seriously threatened due to the activities of blast fishing, coral mining, marine sedimentation, pollution, and global climate change. To determine the existence of coral reefs, it is necessary to study them comprehensively. One method to study a coral reef by using a propagation of sound waves is proposed. In this research, the measurement of reflection coefficient, transmission...

  2. Fishing down nutrients on coral reefs

    Science.gov (United States)

    Allgeier, Jacob E.; Valdivia, Abel; Cox, Courtney; Layman, Craig A.

    2016-08-01

    Fishing is widely considered a leading cause of biodiversity loss in marine environments, but the potential effect on ecosystem processes, such as nutrient fluxes, is less explored. Here, we test how fishing on Caribbean coral reefs influences biodiversity and ecosystem functions provided by the fish community, that is, fish-mediated nutrient capacity. Specifically, we modelled five processes of nutrient storage (in biomass) and supply (via excretion) of nutrients, as well as a measure of their multifunctionality, onto 143 species of coral reef fishes across 110 coral reef fish communities. These communities span a gradient from extreme fishing pressure to protected areas with little to no fishing. We find that in fished sites fish-mediated nutrient capacity is reduced almost 50%, despite no substantial changes in the number of species. Instead, changes in community size and trophic structure were the primary cause of shifts in ecosystem function. These findings suggest that a broader perspective that incorporates predictable impacts of fishing pressure on ecosystem function is imperative for effective coral reef conservation and management.

  3. Impact of Point and Non-point Source Pollution on Coral Reef Ecosystems In Mamala Bay, Oahu, Hawaii based on Water Quality Measurements and Benthic Surveys in 1993-1994 (NODC Accession 0001172)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The effects of both point and non-point sources of pollution on coral reef ecosystems in Mamala Bay were studied at three levels of biological organization; the...

  4. Impact of Global Warming on Coral Reefs

    Directory of Open Access Journals (Sweden)

    Sirilak CHUMKIEW

    2011-06-01

    Full Text Available In this paper, we review coral reef responses to climate variability and discuss the possible mechanisms by which climate impacts the coral reef ecosystem. Effects of oceanographic variables such as sea temperature, turbulence, salinity, and nutrients on the coral reef are discussed in terms of their influence on coral growth, reproduction, mortality, acclimation and adaptation. Organisms tend to be limited to specific thermal ranges with experimental findings showing that sufficient oxygen supply by ventilation and circulation only occurs within these ranges. Indirect effects of climate change on the food web are also discussed. Further integrative studies are required to improve our knowledge of the processes linking coral reef responses to future climate change scenarios.Graphical abstract► Incidence of coral reef bleaching on a worldwide scale: location of bleaching reports during 1979 - 2010. Maps are from ReefBase, www.reefbase.org: 1, Arabian Gulf (United Arab Emirates, Qatar, Iran; 2, Red Sea; 3, east Africa; 4, southern Africa (Mozambique, South Africa; 5, Madagascar; 6, Mauritius, Reunion; 7, Seychelles; 8, Chagos; 9, Maldives; 10, Sri Lanka/southern India; 11, Andaman Sea (Andamans, Thailand, Malaysia; 12, South China Sea (Vietnam, Paracel Islands; 13, Philippines; 14, Indonesia; 15, western Australia; 16, Great Barrier Reef; 17, Ryukyu Islands; 18, Mariana Islands; 19, Palau; 20, Papua New Guinea, Vanuatu; 21, Fiji; 22, Samoa; 23, French Polynesia (including Moorea; 24, Hawaiian Islands; 25, Easter Island; 26, Galapagos Islands; 27, equatorial eastern Pacific (Costa Rica, Cocos Island, Panama´, Colombia, Ecuador; 28, subtropical eastern Pacific (Mexico; 29, Mesoamerican reef system (Mexico, Belize, Honduras, Nicaragua; 30, Greater Antilles (Cuba, Haiti, Dominican Republic, Puerto Rico, Virgin Islands; 31, Bahamas, Florida; 32, Bermuda; 33, Lesser Antilles; 34, Curaçao, Aruba, Bonaire, Los Roques; 35, Brazil.

  5. Resilience of coral reefs in the main Hawaiian Islands from 2013 to 2014 (NCEI Accession 0128219)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Declining health of coral reef ecosystems led scientists to search for factors that support reef resilience: the ability of reefs to resist and recover from...

  6. Devising a Coral Reef Ocean Acidification Monitoring Portfolio

    Science.gov (United States)

    Gledhill, D. K.; Jewett, L.

    2012-12-01

    Coral reef monitoring has frequently been based only on descriptive science with limited capacity to assign specific attribution to agents of change. There is a requirement to engineer a diagnostic monitoring approach that can test predictions regarding the response of coral reef ecosystems to ocean acidification, and to identify potential areas of refugia or areas of particular concern. The approach should provide the means to detect not only changes in water chemistry but also changes in coral reef community structure and function which can be anticipated based upon our current understanding of paleo-OA events, experimental findings, process investigations, and modeling projections In August, 2012 a Coral Reef Ocean Acidification Monitoring Portfolio Workshop was hosted by the NOAA Ocean Acidification Program and the National Coral Reef Institute at the Nova Southeastern University Oceanographic Center. The workshop convened researchers and project managers from around the world engaged in coral reef ecosystems ocean acidification monitoring and research. The workshop sought to define a suite of metrics to include as part of long-term coral reef monitoring efforts that can contribute to discerning specific attribution of changes in coral reef ecosystems in response to ocean acidification. This portfolio of observations should leverage existing and proposed monitoring initiatives and would be derived from a suite of chemical, biogeochemical and ecological measurements. This talk will report out on the key findings from the workshop which should include identifying the most valuable that should be integrated into long-term coral reef ecosystem monitoring that will aid in discerning changes in coral reef ecosystems in response to ocean acidification. The outcomes should provide: recommendations of the most efficient and robust ways to monitor these metrics; identified augmentations that would be required to current ocean acidification monitoring necessary to achieve

  7. A trait-based approach to advance coral reef science

    DEFF Research Database (Denmark)

    Madin, Joshua S.; Hoogenboom, Mia O.; Connolly, Sean R.

    2016-01-01

    Coral reefs are biologically diverse and ecologically complex ecosystems constructed by stony corals. Despite decades of research, basic coral population biology and community ecology questions remain. Quantifying trait variation among species can help resolve these questions, but progress has been...... a large amount of variation for a range of biological and ecological processes. Such an approach can accelerate our understanding of coral ecology and our ability to protect critically threatened global ecosystems....

  8. Consequences of a government-controlled agricultural price increase on fishing and the coral reef ecosystem in the republic of kiribati.

    Directory of Open Access Journals (Sweden)

    Sheila M W Reddy

    Full Text Available BACKGROUND: Economic development policies may have important economic and ecological consequences beyond the sector they target. Understanding these consequences is important to improving these policies and finding opportunities to align economic development with natural resource conservation. These issues are of particular interest to governments and non-governmental organizations that have new mandates to pursue multiple benefits. In this case study, we examined the direct and indirect economic and ecological effects of an increase in the government-controlled price for the primary agricultural product in the Republic of Kiribati, Central Pacific. METHODS/PRINCIPAL FINDINGS: We conducted household surveys and underwater visual surveys of the coral reef to examine how the government increase in the price of copra directly affected copra labor and indirectly affected fishing and the coral reef ecosystem. The islands of Kiribati are coral reef atolls and the majority of households participate in copra agriculture and fishing on the coral reefs. Our household survey data suggest that the 30% increase in the price of copra resulted in a 32% increase in copra labor and a 38% increase in fishing labor. Households with the largest amount of land in coconut production increased copra labor the most and households with the smallest amount of land in coconut production increased fishing the most. Our ecological data suggests that increased fishing labor may result in a 20% decrease in fish stocks and 4% decrease in coral reef-builders. CONCLUSIONS/SIGNIFICANCE: We provide empirical evidence to suggest that the government increase in the copra price in Kiribati had unexpected and indirect economic and ecological consequences. In this case, the economic development policy was not in alignment with conservation. These results emphasize the importance of accounting for differences in household capital and taking a systems approach to policy design and

  9. 40 CFR 230.44 - Coral reefs.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Coral reefs. 230.44 Section 230.44... Aquatic Sites § 230.44 Coral reefs. (a) Coral reefs consist of the skeletal deposit, usually of calcareous... organisms present in growing portions of the reef. (b) Possible loss of values: The discharge of dredged or...

  10. Spatial analyses of benthic habitats to define coral reef ecosystem regions and potential biogeographic boundaries along a latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Brian K Walker

    Full Text Available Marine organism diversity typically attenuates latitudinally from tropical to colder climate regimes. Since the distribution of many marine species relates to certain habitats and depth regimes, mapping data provide valuable information in the absence of detailed ecological data that can be used to identify and spatially quantify smaller scale (10 s km coral reef ecosystem regions and potential physical biogeographic barriers. This study focused on the southeast Florida coast due to a recognized, but understudied, tropical to subtropical biogeographic gradient. GIS spatial analyses were conducted on recent, accurate, shallow-water (0-30 m benthic habitat maps to identify and quantify specific regions along the coast that were statistically distinct in the number and amount of major benthic habitat types. Habitat type and width were measured for 209 evenly-spaced cross-shelf transects. Evaluation of groupings from a cluster analysis at 75% similarity yielded five distinct regions. The number of benthic habitats and their area, width, distance from shore, distance from each other, and LIDAR depths were calculated in GIS and examined to determine regional statistical differences. The number of benthic habitats decreased with increasing latitude from 9 in the south to 4 in the north and many of the habitat metrics statistically differed between regions. Three potential biogeographic barriers were found at the Boca, Hillsboro, and Biscayne boundaries, where specific shallow-water habitats were absent further north; Middle Reef, Inner Reef, and oceanic seagrass beds respectively. The Bahamas Fault Zone boundary was also noted where changes in coastal morphologies occurred that could relate to subtle ecological changes. The analyses defined regions on a smaller scale more appropriate to regional management decisions, hence strengthening marine conservation planning with an objective, scientific foundation for decision making. They provide a framework

  11. Are coral reefs victims of their own past success?

    Science.gov (United States)

    Renema, Willem; Pandolfi, John M; Kiessling, Wolfgang; Bosellini, Francesca R; Klaus, James S; Korpanty, Chelsea; Rosen, Brian R; Santodomingo, Nadiezhda; Wallace, Carden C; Webster, Jody M; Johnson, Kenneth G

    2016-04-01

    As one of the most prolific and widespread reef builders, the staghorn coral Acropora holds a disproportionately large role in how coral reefs will respond to accelerating anthropogenic change. We show that although Acropora has a diverse history extended over the past 50 million years, it was not a dominant reef builder until the onset of high-amplitude glacioeustatic sea-level fluctuations 1.8 million years ago. High growth rates and propagation by fragmentation have favored staghorn corals since this time. In contrast, staghorn corals are among the most vulnerable corals to anthropogenic stressors, with marked global loss of abundance worldwide. The continued decline in staghorn coral abundance and the mounting challenges from both local stress and climate change will limit the coral reefs' ability to provide ecosystem services.

  12. 珊瑚礁区碳循环研究进展%Recent development in the research of carbon cycle in coral reef ecosystem

    Institute of Scientific and Technical Information of China (English)

    严宏强; 余克服; 谭烨辉

    2009-01-01

    The carbon cycle in coral reefs, one of the most productive ecosystems in the ocean, includes the combination of organic carbon metabolism (photosynthesis/ respiration) and inorganic carbon metabolism (calcification / dissolution). The photosynthesis of plants in coral reefs converts CO_2 into organic carbon, making a useful supplement to organic carbon cycle. Because of the highly efficient organic carbon cycle facilitated by coral reef animals′ feeding activities and micro-biological degradation, there are no more than 7% of organic carbon being precipitated into sediment. While the horizontal flux of organic carbon transported into ocean is greatly controlled by hydrodynamic conditions and can vary widely. The carbonate precipitated during inorganic carbon metabolism on coral reefs is an important part of global carbonate reservoir, which contributes 23%-26% of global CaCO_3 accumulation and affects atmospheric CO_2 concentration. Net organic-to-inorganic carbon production ratio (ROI) is developed as a criterion in reflecting the sink/source behavior of CO_2 on coral reefs. When ROI is less than 0.6, the coral reef is the source of atmospheric CO_2, otherwise the coral reef acts as a sink of atmospheric CO_2. The recent work has established the preliminary understanding on the biogeochemical process of coral reef carbon cycle, thus the ongoing research will cover the mechanism of efficient organic carbon cycle of coral reefs, the function of coral reef organisms on carbon cycle, and the response of coral reef carbon cycle to climate change etc.%珊瑚礁是海洋中生产力水平最高的生态系统之一,其碳循环受到有机碳代谢(光合作用/呼吸作用)和无机碳代谢(钙化/溶解)两大代谢过程的共同作用,过程十分复杂.珊瑚礁植物的光合作用保证了有机碳的有效补充,动物摄食及微生物降解等生物过程驱动了珊瑚礁区有机碳高效循环,只有不超过7%的有机碳进入沉积物,而向大洋

  13. 77 FR 39724 - U.S. Coral Reef Task Force Public Meeting and Public Comment

    Science.gov (United States)

    2012-07-05

    ...-123D0102DM-DS61200000] U.S. Coral Reef Task Force Public Meeting and Public Comment AGENCY: Fish and Wildlife.... Fish and Wildlife Service (Service), announce a public meeting of the U.S. Coral Reef Task Force... better preserve and protect coral reef ecosystems. The Departments of Commerce and the Interior co-chair...

  14. Experimental Bleaching of a Reef-Building Coral Using a Simplified Recirculating Laboratory Exposure System

    Science.gov (United States)

    Determining stressor-response relationships in reef building corals is a critical need for researchers because of global declines in coral reef ecosystems. A simplified recirculating coral exposure system for laboratory testing of a diversity of species and morphologies of reef b...

  15. Experimental Bleaching of a Reef-Building Coral Using a Simplified Recirculating Laboratory Exposure System

    Science.gov (United States)

    Determining stressor-response relationships in reef building corals is a critical need for researchers because of global declines in coral reef ecosystems. A simplified recirculating coral exposure system for laboratory testing of a diversity of species and morphologies of reef b...

  16. Understanding coral reefs in an impacted world: Physiological responses of coral reef organisms to coastal pollution and global warming

    OpenAIRE

    Kegler, Pia

    2015-01-01

    Coral reefs are facing a multitude of anthropogenic disturbances at ever higher frequencies and magnitudes. As a consequence, these ecologically and economically important ecosystems are degrading worldwide. Reef managers lack knowledge on how fish, corals and coral larvae respond to the effects of local and global stressors. This thesis reveals the significance of chemical pollution from localized sources. Two common pollutants (diesel and a surfactant) caused metabolic changes in a fish and...

  17. Shifts in coral-assemblage composition do not ensure persistence of reef functionality.

    Science.gov (United States)

    Alvarez-Filip, Lorenzo; Carricart-Ganivet, Juan P; Horta-Puga, Guillermo; Iglesias-Prieto, Roberto

    2013-12-12

    Coral communities are changing rapidly worldwide through loss of coral cover and shifts in species composition. Although many reef-building corals are likely to decline, some weedy opportunistic species might increase in abundance. Here we explore whether the reshuffling of species can maintain ecosystem integrity and functioning. Using four common Caribbean reef-building coral genera we modeled rates of reef construction and complexity. We show that shifting coral assemblages result in rapid losses in coral-community calcification and reef rugosity that are independent of changes in the total abundance of reef corals. These losses are considerably higher than those recently attributed to climate change. Dominance patterns of coral assemblages seem to be the most important driver of the functioning of coral reefs and thus, the future of these ecosystems might depend not only on reductions of local and global stressors, but also on the maintenance of keystone coral species.

  18. Human Impacts to Coastal Ecosystems in Puerto Rico (HICE-PR): Actual Condition of Coral Reefs Associated with the Guanica and Manati Watersheds in Puerto Rico

    Science.gov (United States)

    Torres-Perez, J. L.; Barreto, M.; Guild, L. S.; Ortiz, J.; Setegn, S. G.; Ramos-Scharron, C. E.; Armstrong, R.; Santiago, L.

    2015-12-01

    For several decades Puerto Rico's coastal and marine ecosystems (CMEs), particularly coral reefs, have suffered the effects of anthropogenic stresses associated to population growth and varying land use. Here we present an overview of the first year of findings of a NASA-funded project that studies human impacts in two priority watersheds (Manatí and Guánica). The project includes remote sensing analysis and hydrological, ecological and socio-economic modeling to provide a multi-decadal assessment of change of CMEs. The project's main goal is to evaluate the impacts of land use/land cover changes on the quality and extent of CMEs in priority watersheds in the north and south coasts of Puerto Rico. This project will include imagery from Landsat 8 to assess coastal ecosystems extent. Habitat and species distribution maps will be created by incorporating field and remotely-sensed data into an Ecological Niche Factor Analysis. The social component will allow us to study the valuation of specific CMEs attributes from the stakeholder's point of view. Field data was collected through a series of phototransects at the main reefs associated with these two priority watersheds. A preliminary assessment shows a range in coral cover from 0.2-30% depending on the site (Guánica) whereas apparently healthy corals dominate the reef in the north coast (Manatí). Reefs on the southwest coast of PR (Guánica) show an apparent shift from hard corals to a more algae and soft corals dominance after decades of anthropogenic impacts (sedimentation, eutrophication, mechanical damage through poorly supervised recreational activities, etc.). Additionally preliminary results from land cover/land use changes analyses show dynamic historical shoreline changes in beaches located west of the Manatí river mouth and a degradation of water quality in Guánica possibly being one of the main factors affecting the actual condition of its CMEs.

  19. Climate change and coral reef connectivity

    Science.gov (United States)

    Munday, P. L.; Leis, J. M.; Lough, J. M.; Paris, C. B.; Kingsford, M. J.; Berumen, M. L.; Lambrechts, J.

    2009-06-01

    This review assesses and predicts the impacts that rapid climate change will have on population connectivity in coral reef ecosystems, using fishes as a model group. Increased ocean temperatures are expected to accelerate larval development, potentially leading to reduced pelagic durations and earlier reef-seeking behaviour. Depending on the spatial arrangement of reefs, the expectation would be a reduction in dispersal distances and the spatial scale of connectivity. Small increase in temperature might enhance the number of larvae surviving the pelagic phase, but larger increases are likely to reduce reproductive output and increase larval mortality. Changes to ocean currents could alter the dynamics of larval supply and changes to planktonic productivity could affect how many larvae survive the pelagic stage and their condition at settlement; however, these patterns are likely to vary greatly from place-to-place and projections of how oceanographic features will change in the future lack sufficient certainty and resolution to make robust predictions. Connectivity could also be compromised by the increased fragmentation of reef habitat due to the effects of coral bleaching and ocean acidification. Changes to the spatial and temporal scales of connectivity have implications for the management of coral reef ecosystems, especially the design and placement of marine-protected areas. The size and spacing of protected areas may need to be strategically adjusted if reserve networks are to retain their efficacy in the future.

  20. Fisheries management: what chance on coral reefs?

    OpenAIRE

    1996-01-01

    Failures of fishery management to control fishing effort globally and how this affects the coral reef fisheries are discussed. The use of marine reserves in coral reef fisheries management is also emphasized.

  1. {delta}{sup 15}N of seagrass leaves for monitoring anthropogenic nutrient increases in coral reef ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Yamamuro, M.; Kayanne, H.; Yamano, H

    2003-04-01

    In a coral reef environment, a slight increase in dissolved inorganic nitrogen (DIN;{>=}1.0 {mu}M) can alter the ecosystem via macroalgal blooms. We collected seagrass leaves from the tropical and subtropical Pacific Ocean in five countries and examined the interactions between nutrient concentrations (C, N, P), molar ratios of nutrients, and {delta}{sup 15}N to find a possible indicator of the DIN conditions. Within most sites, the concentrations of nutrients and their molar ratios showed large variations owing to species-specific values. On the other hand, almost identical {delta}{sup 15}N values were found in seagrass leaves of several species at each site. The correlations between {delta}{sup 15}N and nutrient concentrations and between {delta}{sup 15}N and molar ratios of nutrients suggested that nutrient availability did not affect the {delta}{sup 15}N value of seagrass leaves by altering the physiological condition of the plants. Increases in {delta}{sup 15}N of seagrass leaves mostly matched increases in DIN concentrations in the bottom water. We suggest that {delta}{sup 15}N in seagrass leaves can be a good tool to monitor time-integrated decrease/increase of DIN concentrations at a site, both in the water column and the interstitial water.

  2. Sediments and herbivory as sensitive indicators of coral reef degradation

    Directory of Open Access Journals (Sweden)

    Christopher H. R. Goatley

    2016-03-01

    Full Text Available Around the world, the decreasing health of coral reef ecosystems has highlighted the need to better understand the processes of reef degradation. The development of more sensitive tools, which complement traditional methods of monitoring coral reefs, may reveal earlier signs of degradation and provide an opportunity for pre-emptive responses. We identify new, sensitive metrics of ecosystem processes and benthic composition that allow us to quantify subtle, yet destabilizing, changes in the ecosystem state of an inshore coral reef on the Great Barrier Reef. Following severe climatic disturbances over the period 2011-2012, the herbivorous reef fish community of the reef did not change in terms of biomass or functional groups present. However, fish-based ecosystem processes showed marked changes, with grazing by herbivorous fishes declining by over 90%. On the benthos, algal turf lengths in the epilithic algal matrix increased more than 50% while benthic sediment loads increased 37-fold. The profound changes in processes, despite no visible change in ecosystem state, i.e., no shift to macroalgal dominance, suggest that although the reef has not undergone a visible regime-shift, the ecosystem is highly unstable, and may sit on an ecological knife-edge. Sensitive, process-based metrics of ecosystem state, such as grazing or browsing rates thus appear to be effective in detecting subtle signs of degradation and may be critical in identifying ecosystems at risk for the future.

  3. Could some coral reefs become sponge reefs as our climate changes?

    Science.gov (United States)

    Bell, James J; Davy, Simon K; Jones, Timothy; Taylor, Michael W; Webster, Nicole S

    2013-09-01

    Coral reefs across the world have been seriously degraded and have a bleak future in response to predicted global warming and ocean acidification (OA). However, this is not the first time that biocalcifying organisms, including corals, have faced the threat of extinction. The end-Triassic mass extinction (200 million years ago) was the most severe biotic crisis experienced by modern marine invertebrates, which selected against biocalcifiers; this was followed by the proliferation of another invertebrate group, sponges. The duration of this sponge-dominated period far surpasses that of alternative stable-ecosystem or phase-shift states reported on modern day coral reefs and, as such, a shift to sponge-dominated reefs warrants serious consideration as one future trajectory of coral reefs. We hypothesise that some coral reefs of today may become sponge reefs in the future, as sponges and corals respond differently to changing ocean chemistry and environmental conditions. To support this hypothesis, we discuss: (i) the presence of sponge reefs in the geological record; (ii) reported shifts from coral- to sponge-dominated systems; and (iii) direct and indirect responses of the sponge holobiont and its constituent parts (host and symbionts) to changes in temperature and pH. Based on this evidence, we propose that sponges may be one group to benefit from projected climate change and ocean acidification scenarios, and that increased sponge abundance represents a possible future trajectory for some coral reefs, which would have important implications for overall reef functioning. © 2013 John Wiley & Sons Ltd.

  4. Coral Reef Ecosystems of American Samoa, a 2002-2010 Overview

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This booklet provides an overview of key findings and temporal trends from the Pacific Reef Assessment and Monitoring Program (Pacific RAMP) research surveys...

  5. Acoustic Tracking of Fish Movements in Coral Reef Ecosystems in St John (USVI), 2006-2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Acoustic Tracking of Reef Fishes to Elucidate Habitat Utilization Patterns and Residence Times Inside and Outside Marine Protected Areas Around the Island of St....

  6. Acoustic Tracking of Fish Movements in Coral Reef Ecosystems in St John (USVI), 2006-2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Acoustic Tracking of Reef Fishes to Elucidate Habitat Utilization Patterns and Residence Times Inside and Outside Marine Protected Areas Around the Island of St....

  7. The wicked problem of China's disappearing coral reefs.

    Science.gov (United States)

    Hughes, Terry P; Huang, Hui; Young, Matthew A L

    2013-04-01

    We examined the development of coral reef science and the policies, institutions, and governance frameworks for management of coral reefs in China in order to highlight the wicked problem of preserving reefs while simultaneously promoting human development and nation building. China and other sovereign states in the region are experiencing unprecedented economic expansion, rapid population growth, mass migration, widespread coastal development, and loss of habitat. We analyzed a large, fragmented literature on the condition of coral reefs in China and the disputed territories of the South China Sea. We found that coral abundance has declined by at least 80% over the past 30 years on coastal fringing reefs along the Chinese mainland and adjoining Hainan Island. On offshore atolls and archipelagos claimed by 6 countries in the South China Sea, coral cover has declined from an average of >60% to around 20% within the past 10-15 years. Climate change has affected these reefs far less than coastal development, pollution, overfishing, and destructive fishing practices. Ironically, these widespread declines in the condition of reefs are unfolding as China's research and reef-management capacity are rapidly expanding. Before the loss of corals becomes irreversible, governance of China's coastal reefs could be improved by increasing public awareness of declining ecosystem services, by providing financial support for training of reef scientists and managers, by improving monitoring of coral reef dynamics and condition to better inform policy development, and by enforcing existing regulations that could protect coral reefs. In the South China Sea, changes in policy and legal frameworks, refinement of governance structures, and cooperation among neighboring countries are urgently needed to develop cooperative management of contested offshore reefs.

  8. Do tabular corals constitute keystone structures for fishes on coral reefs?

    Science.gov (United States)

    Kerry, J. T.; Bellwood, D. R.

    2015-03-01

    This study examined the changes in community composition of reef fishes by experimentally manipulating the availability of shelter provided by tabular structures on a mid-shelf reef on the Great Barrier Reef. At locations where access to tabular corals ( Acropora hyacinthus and Acropora cytherea) was excluded, a rapid and sustained reduction in the abundance of large reef fishes occurred. At locations where tabular structure was added, the abundance and diversity of large reef fishes increased and the abundance of small reef fishes tended to decrease, although over a longer time frame. Based on their response to changes in the availability of tabular structures, nine families of large reef fishes were separated into three categories; designated as obligate, facultative or non-structure users. This relationship may relate to the particular ecological demands of each family, including avoidance of predation and ultraviolet radiation, access to feeding areas and reef navigation. This study highlights the importance of tabular corals for large reef fishes in shallow reef environments and provides a possible mechanism for local changes in the abundance of reef fishes following loss of structural complexity on coral reefs. Keystone structures have a distinct structure and disproportionate effect on their ecosystem relative to their abundance, as such the result of this study suggests tabular corals may constitute keystone structures on shallow coral reefs.

  9. NOAA's Coral Reef Conservation Program: 2016 Projects Monitoring the Effects of Thermal Stress on Coral Bleaching

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Climate change impacts have been identified as one of the greatest global threats to coral reef ecosystems. As temperature rise, mass bleaching, and infectious...

  10. CRED REA Belt Surveys of Coral Population and Disease Assessments at Kingman Reef, Pacific Remote Island Areas in 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 14-19 April 2010, belt...

  11. CRED REA Belt Surveys of Coral Population and Disease Assessments at Maro Reef, NW Hawaiian Islands in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To support a long-term NOAA Coral Reef Conservation Program (CRCP) for sustainable management and conservation of coral reef ecosystems, from 12 September - 12...

  12. Coral reef diseases in the Atlantic-Caribbean

    Science.gov (United States)

    Rogers, Caroline S.; Weil, Ernesto; Dubinsky, Zvy; Stambler, Noga

    2010-01-01

    Coral reefs are the jewels of the tropical oceans. They boast the highest diversity of all marine ecosystems, aid in the development and protection of other important, productive coastal marine communities, and have provided millions of people with food, building materials, protection from storms, recreation and social stability over thousands of years, and more recently, income, active pharmacological compounds and other benefits. These communities have been deteriorating rapidly in recent times. The continuous emergence of coral reef diseases and increase in bleaching events caused in part by high water temperatures among other factors underscore the need for intensive assessments of their ecological status and causes and their impact on coral reefs.

  13. Coral Reef Monitoring: From Cytological Parameters to Community Indices

    Directory of Open Access Journals (Sweden)

    Ofer Ben-Tzvi

    2011-01-01

    Full Text Available Sound-ecosystem-based management of coral reefs is largely based on indicators of reef health state. Currently there are various ecological parameters that serve as reef state indices; however, their practical implications are under debate. In the present study we examine an alternative parameter, the deterioration index (DI, which does not purport to replace the traditional indices but can provide a reliable, stand-alone indication of reef state. Patterns of cytological indices, which are considered as reliable indicators of environmental stressors, have been compared to ten selected reef community indices. The DI showed the highest correlations among community indices to the cytological indices in artificial reefs and high correlation in natural reefs as well. Our results suggest that in cases of lacking adequate monitoring abilities where a full set of community indices cannot be obtained, the DI can serve in many cases as the preferred, stand-alone indicator of coral reef state.

  14. Drivers and predictions of coral reef carbonate budget trajectories

    Science.gov (United States)

    Graham, Nicholas A. J.; Jennings, Simon; Perry, Chris T.

    2017-01-01

    Climate change is one of the greatest threats to the long-term maintenance of coral-dominated tropical ecosystems, and has received considerable attention over the past two decades. Coral bleaching and associated mortality events, which are predicted to become more frequent and intense, can alter the balance of different elements that are responsible for coral reef growth and maintenance. The geomorphic impacts of coral mass mortality have received relatively little attention, particularly questions concerning temporal recovery of reef carbonate production and the factors that promote resilience of reef growth potential. Here, we track the biological carbonate budgets of inner Seychelles reefs from 1994 to 2014, spanning the 1998 global bleaching event when these reefs lost more than 90% of coral cover. All 21 reefs had positive budgets in 1994, but in 2005 budgets were predominantly negative. By 2014, carbonate budgets on seven reefs were comparable with 1994, but on all reefs where an ecological regime shift to macroalgal dominance occurred, budgets remained negative through 2014. Reefs with higher massive coral cover, lower macroalgae cover and lower excavating parrotfish biomass in 1994 were more likely to have positive budgets post-bleaching. If mortality of corals from the 2016 bleaching event is as severe as that of 1998, our predictions based on past trends would suggest that six of eight reefs with positive budgets in 2014 would still have positive budgets by 2030. Our results highlight that reef accretion and framework maintenance cannot be assumed from the ecological state alone, and that managers should focus on conserving aspects of coral reefs that support resilient carbonate budgets. PMID:28123092

  15. Drivers and predictions of coral reef carbonate budget trajectories.

    Science.gov (United States)

    Januchowski-Hartley, Fraser A; Graham, Nicholas A J; Wilson, Shaun K; Jennings, Simon; Perry, Chris T

    2017-01-25

    Climate change is one of the greatest threats to the long-term maintenance of coral-dominated tropical ecosystems, and has received considerable attention over the past two decades. Coral bleaching and associated mortality events, which are predicted to become more frequent and intense, can alter the balance of different elements that are responsible for coral reef growth and maintenance. The geomorphic impacts of coral mass mortality have received relatively little attention, particularly questions concerning temporal recovery of reef carbonate production and the factors that promote resilience of reef growth potential. Here, we track the biological carbonate budgets of inner Seychelles reefs from 1994 to 2014, spanning the 1998 global bleaching event when these reefs lost more than 90% of coral cover. All 21 reefs had positive budgets in 1994, but in 2005 budgets were predominantly negative. By 2014, carbonate budgets on seven reefs were comparable with 1994, but on all reefs where an ecological regime shift to macroalgal dominance occurred, budgets remained negative through 2014. Reefs with higher massive coral cover, lower macroalgae cover and lower excavating parrotfish biomass in 1994 were more likely to have positive budgets post-bleaching. If mortality of corals from the 2016 bleaching event is as severe as that of 1998, our predictions based on past trends would suggest that six of eight reefs with positive budgets in 2014 would still have positive budgets by 2030. Our results highlight that reef accretion and framework maintenance cannot be assumed from the ecological state alone, and that managers should focus on conserving aspects of coral reefs that support resilient carbonate budgets. © 2017 The Authors.

  16. Predicting climate-driven regime shifts versus rebound potential in coral reefs.

    Science.gov (United States)

    Graham, Nicholas A J; Jennings, Simon; MacNeil, M Aaron; Mouillot, David; Wilson, Shaun K

    2015-02-05

    Climate-induced coral bleaching is among the greatest current threats to coral reefs, causing widespread loss of live coral cover. Conditions under which reefs bounce back from bleaching events or shift from coral to algal dominance are unknown, making it difficult to predict and plan for differing reef responses under climate change. Here we document and predict long-term reef responses to a major climate-induced coral bleaching event that caused unprecedented region-wide mortality of Indo-Pacific corals. Following loss of >90% live coral cover, 12 of 21 reefs recovered towards pre-disturbance live coral states, while nine reefs underwent regime shifts to fleshy macroalgae. Functional diversity of associated reef fish communities shifted substantially following bleaching, returning towards pre-disturbance structure on recovering reefs, while becoming progressively altered on regime shifting reefs. We identified threshold values for a range of factors that accurately predicted ecosystem response to the bleaching event. Recovery was favoured when reefs were structurally complex and in deeper water, when density of juvenile corals and herbivorous fishes was relatively high and when nutrient loads were low. Whether reefs were inside no-take marine reserves had no bearing on ecosystem trajectory. Although conditions governing regime shift or recovery dynamics were diverse, pre-disturbance quantification of simple factors such as structural complexity and water depth accurately predicted ecosystem trajectories. These findings foreshadow the likely divergent but predictable outcomes for reef ecosystems in response to climate change, thus guiding improved management and adaptation.

  17. Coral reef baselines: how much macroalgae is natural?

    Science.gov (United States)

    Bruno, John F; Precht, William F; Vroom, Peter S; Aronson, Richard B

    2014-03-15

    Identifying the baseline or natural state of an ecosystem is a critical step in effective conservation and restoration. Like most marine ecosystems, coral reefs are being degraded by human activities: corals and fish have declined in abundance and seaweeds, or macroalgae, have become more prevalent. The challenge for resource managers is to reverse these trends, but by how much? Based on surveys of Caribbean reefs in the 1970s, some reef scientists believe that the average cover of seaweed was very low in the natural state: perhaps less than 3%. On the other hand, evidence from remote Pacific reefs, ecological theory, and impacts of over-harvesting in other systems all suggest that, historically, macroalgal biomass may have been higher than assumed. Uncertainties about the natural state of coral reefs illustrate the difficulty of determining the baseline condition of even well studied systems.

  18. Morphogenesis of the branching reef coral Madracis mirabilis

    NARCIS (Netherlands)

    Kaandorp, J.A.; Sloot, P.M.A.; Merks, R.M.H.; Bak, R.P.M.; Vermeij, M.J.A.; Maier, C.

    2005-01-01

    Understanding external deciding factors in growth and morphology of reef corals is essential to elucidate the role of corals in marine ecosystems, and to explain their susceptibility to pollution and global climate change. Here, we extend on a previously presented model for simulating the growth and

  19. The Economic Impact of Ocean Acidification on Coral Reefs

    OpenAIRE

    Brander, Luke M.; Rehdanz, Katrin; Tol, Richard S. J.; van Beukering, Pieter J.H.

    2009-01-01

    Because ocean acidification has only recently been recognized as a problem caused by CO2 emissions, impact studies are still rare and estimates of the economic impact are absent. This paper estimates the economic impact of ocean acidification on coral reefs which are generally considered to be economically as well as ecologically important ecosystems. First, we conduct an impact assessment in which atmospheric concentration of CO2 is linked to ocean acidity causing coral reef area loss. Next,...

  20. Ophiuroidea (Echinodermata) from coral reefs in the Mexican Pacific

    OpenAIRE

    Rebeca Granja Fernández; María Dinorah Herrero Pérezrul; Ramón Andrés López Pérez; Luis Hernández; Fabián Rodríguez Zaragoza; Robert Wallace Jones; Rubén Pineda López

    2014-01-01

    Abstract There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of...

  1. Bacterial Diversity Associated with Cinachyra cavernosa and Haliclona pigmentifera, Cohabiting Sponges in the Coral Reef Ecosystem of Gulf of Mannar, Southeast Coast of India.

    Directory of Open Access Journals (Sweden)

    C Jasmin

    Full Text Available Sponges are abundant, diverse and functionally important organisms of coral reef ecosystems. Sponge-associated microorganisms have been receiving greater attention because of their significant contribution to sponge biomass, biogeochemical cycles and biotechnological potentials. However, our understanding of the sponge microbiome is limited to a few species of sponges from restricted geographical locations. Here, we report for the first time the bacterial diversity of two cohabiting sponges, viz. Cinachyra cavernosa and Haliclona pigmentifera, as well as that in the ambient water from the coral reef ecosystems of the Gulf of Mannar, located along the southeast coast of India. Two hundred and fifty two clones in the 16S rRNA gene library of these sponges were grouped into eight distinct phyla, of which four belonged to the core group that are associated only with sponges. Phylogenetic analysis of the core bacteria showed close affinity to other sponge-associated bacteria from different geographical locations. γ-Proteobacteria, Chloroflexi, Planctomycetes and Deferribacter were the core groups in C. cavernosa while β and δ-Proteobacteria performed this role in H. pigmentifera. We observed greater OTU diversity for C. cavernosa (Hǀ 2.07 compared to H. pigmentifera (Hǀ 1.97. UniFrac analysis confirmed the difference in bacterial diversity of the two sponge species and also between the sponges and the reef water (p<0.001. The results of our study restate the existence of a host driven force in shaping the sponge microbiome.

  2. Coral similarity and connectivity of some reefs of the Gulf of Mexico and the Mexican Caribbean

    OpenAIRE

    Chávez-Hidalgo, A.; De la Cruz-Agüero, G.; Chávez, E.A.

    2010-01-01

    Coral reef connectivity results from the export and import of species or reproductive product between localities. Possible exchange pathways between the reef ecosystems in the country are not known; such knowledge about coral reef connectivity could contribute to its management and conservation. The connectivity between reefs of the Gulf of Mexico and Mexican Caribbean was evaluated based on patterns of similarity — information for 55 stony coral species in 17 localities. Species richness sug...

  3. Experimental Bleaching of a Reef-Building Coral Using a Simplified Recirculating Laboratory Exposure System

    OpenAIRE

    Barron, Mace G.; McGill, Cheryl J.; Courtney, Lee A.; Marcovich, Dragoslav T.

    2010-01-01

    Determining stressor-response relationships in reef building corals continues to be a critical research need due to global declines in coral reef ecosystems and projected declines for the future. A simplified recirculating coral exposure system was coupled to a solar simulator to allow laboratory testing of a diversity of species and morphologies of reef building corals under ecologically relevant conditions of temperature and solar radiation. Combinations of lamps and attenuating filters al...

  4. Experimental Bleaching of a Reef-Building Coral Using a Simplified Recirculating Laboratory Exposure System

    OpenAIRE

    Barron, Mace G.; Cheryl J. McGill; Courtney, Lee A.; Marcovich, Dragoslav T

    2010-01-01

    Determining stressor-response relationships in reef building corals continues to be a critical research need due to global declines in coral reef ecosystems and projected declines for the future. A simplified recirculating coral exposure system was coupled to a solar simulator to allow laboratory testing of a diversity of species and morphologies of reef building corals under ecologically relevant conditions of temperature and solar radiation. Combinations of lamps and attenuating filters al...

  5. Short-term and seasonal pH,pCO2and saturation state variability in a coral-reef ecosystem

    Science.gov (United States)

    Gray, Sarah E. C.; Degrandpre, Michael D.; Langdon, Chris; Corredor, Jorge E.

    2012-09-01

    Coral reefs are predicted to be one of the ecosystems most sensitive to ocean acidification. To improve predictions of coral reef response to acidification, we need to better characterize the natural range of variability of pH, partial pressure of carbon dioxide (pCO2) and calcium carbonate saturation states (Ω). In this study, autonomous sensors for pH and pCO2 were deployed on Media Luna reef, Puerto Rico over three seasons from 2007 to 2008. High temporal resolution CaCO3 saturation states were calculated from the in situ data, giving a much more detailed characterization of reef saturation states than previously possible. Reef pH, pCO2 and aragonite saturation (ΩAr) ranged from 7.89 to 8.17 pH units, 176-613 μatm and 2.7-4.7, respectively, in the range characteristic of most other previously studied reef ecosystems. The diel pH, pCO2 and Ω cycles were also large, encompassing about half of the seasonal range of variability. Warming explained about 50% of the seasonal supersaturation in mean pCO2, with the remaining supersaturation primarily due to net heterotrophy and net CaCO3 production. Net heterotrophy was likely driven by remineralization of mangrove derived organic carbon which continued into the fall, sustaining high pCO2 levels until early winter when the pCO2 returned to offshore values. As a consequence, the reef was a source of CO2 to the atmosphere during the summer and fall and a sink during winter, resulting in a net annual source of 0.73 ± 1.7 mol m-2 year-1. These results show that reefs are exposed to a wide range of saturation states in their natural environment. Mean ΩAr levels will drop to 3.0 when atmospheric CO2 increases to 500 μatm and ΩAr will be less than 3.0 for greater than 70% of the time in the summer. Long duration exposure to these low ΩAr levels are expected to significantly decrease calcification rates on the reef.

  6. Sensing coral reef connectivity pathways from space

    KAUST Repository

    Raitsos, Dionysios E.

    2017-08-18

    Coral reefs rely on inter-habitat connectivity to maintain gene flow, biodiversity and ecosystem resilience. Coral reef communities of the Red Sea exhibit remarkable genetic homogeneity across most of the Arabian Peninsula coastline, with a genetic break towards the southern part of the basin. While previous studies have attributed these patterns to environmental heterogeneity, we hypothesize that they may also emerge as a result of dynamic circulation flow; yet, such linkages remain undemonstrated. Here, we integrate satellite-derived biophysical observations, particle dispersion model simulations, genetic population data and ship-borne in situ profiles to assess reef connectivity in the Red Sea. We simulated long-term (>20 yrs.) connectivity patterns driven by remotely-sensed sea surface height and evaluated results against estimates of genetic distance among populations of anemonefish, Amphiprion bicinctus, along the eastern Red Sea coastline. Predicted connectivity was remarkably consistent with genetic population data, demonstrating that circulation features (eddies, surface currents) formulate physical pathways for gene flow. The southern basin has lower physical connectivity than elsewhere, agreeing with known genetic structure of coral reef organisms. The central Red Sea provides key source regions, meriting conservation priority. Our analysis demonstrates a cost-effective tool to estimate biophysical connectivity remotely, supporting coastal management in data-limited regions.

  7. American Samoa: coral reef monitoring interactive map and information layers primarily from 2010 surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This interactive map displays American Samoa data collected by the NOAA Coral Reef Ecosystem Division (CRED) during the Pacific Reef Assessment and Monitoring...

  8. New tool to manage coral reefs

    Science.gov (United States)

    Showstack, Randy

    The National Oceanic and Atmospheric Administration is making available a new tool for coral reef managers to monitor the cumulative thermal stress of several coral reefs around the world, including the Great Barrier Reef, and reefs by the Galapagos Islands, the agency announced on 25 February.The agency's "Degree Heating Weeks" product uses satellite-derived information to allow continuous monitoring of the extent and acuteness of thermal stress, which are key predictors of coral bleaching, and which contribute to coral reef degradation.

  9. Changes in biodiversity and functioning of reef fish assemblages following coral bleaching and coral loss

    KAUST Repository

    Pratchett, M.S.

    2011-08-12

    Coral reef ecosystems are increasingly subject to severe, large-scale disturbances caused by climate change (e.g., coral bleaching) and other more direct anthropogenic impacts. Many of these disturbances cause coral loss and corresponding changes in habitat structure, which has further important effects on abundance and diversity of coral reef fishes. Declines in the abundance and diversity of coral reef fishes are of considerable concern, given the potential loss of ecosystem function. This study explored the effects of coral loss, recorded in studies conducted throughout the world, on the diversity of fishes and also on individual responses of fishes within different functional groups. Extensive (>60%) coral loss almost invariably led to declines in fish diversity. Moreover, most fishes declined in abundance following acute disturbances that caused >10% declines in local coral cover. Response diversity, which is considered critical in maintaining ecosystem function and promoting resilience, was very low for corallivores, but was much higher for herbivores, omnivores and carnivores. Sustained and ongoing climate change thus poses a significant threat to coral reef ecosystems and diversity hotspots are no less susceptible to projected changes in diversity and function.

  10. Changes in Biodiversity and Functioning of Reef Fish Assemblages following Coral Bleaching and Coral Loss

    Directory of Open Access Journals (Sweden)

    Nicholas A.J. Graham

    2011-08-01

    Full Text Available Coral reef ecosystems are increasingly subject to severe, large-scale disturbances caused by climate change (e.g., coral bleaching and other more direct anthropogenic impacts. Many of these disturbances cause coral loss and corresponding changes in habitat structure, which has further important effects on abundance and diversity of coral reef fishes. Declines in the abundance and diversity of coral reef fishes are of considerable concern, given the potential loss of ecosystem function. This study explored the effects of coral loss, recorded in studies conducted throughout the world, on the diversity of fishes and also on individual responses of fishes within different functional groups. Extensive (>60% coral loss almost invariably led to declines in fish diversity. Moreover, most fishes declined in abundance following acute disturbances that caused >10% declines in local coral cover. Response diversity, which is considered critical in maintaining ecosystem function and promoting resilience, was very low for corallivores, but was much higher for herbivores, omnivores and carnivores. Sustained and ongoing climate change thus poses a significant threat to coral reef ecosystems and diversity hotspots are no less susceptible to projected changes in diversity and function.

  11. First Record of Porpita porpita (Cnidaria: Hydrozoa) from the coral reef ecosystem, Bangladesh

    Science.gov (United States)

    Chowdhury, M. Shah Nawaz; Sharifuzzaman, S. M.; Chowdhury, Sayedur Rahman; Rashed-Un-Nabi, Md.; Hossain, M. Shahadat

    2016-03-01

    The occurrence of Porpita porpita is reported, for the first time, in the coral island of St. Martin's located in the southeastern coastal region of Bangladesh. P. porpita was found to occur in the lower littoral zone and beach rock pools, together with molluscan species, and collected during the pre-monsoon season when both water temperature (> 30°C) and salinity (> 30‰) tend to reach a maximum. This study recounts some details on the discovery and description of the species, and thus extends the global distribution and range limits of the genus Porpita.

  12. 75 FR 48934 - Coral Reef Conservation Program Implementation Guidelines

    Science.gov (United States)

    2010-08-12

    ... National Oceanic and Atmospheric Administration RIN 0648-ZC19 Coral Reef Conservation Program... Implementation Guidelines for the Coral Reef Conservation Program. SUMMARY: This document provides NOAA's revised Grant Program Implementation Guidelines (Guidelines) for the Coral Reef Conservation Program (CRCP or...

  13. Novel tradable instruments in the conservation of coral reefs, based on the coral gardening concept for reef restoration.

    Science.gov (United States)

    Rinkevich, Baruch

    2015-10-01

    Nearly all coral reefs bordering nations have experienced net losses in reef biodiversity, goods and services, even without considering the ever-developing global change impacts. In response, this overview wishes to reveal through prospects of active reef-restoration, the currently non-marketed or poorly marketed reef services, focusing on a single coral species (Stylophora pistillata). It is implied that the integration of equity capitals and other commodification with reef-restoration practices will improve total reef services. Two tiers of market-related activities are defined, the traditional first-tier instruments (valuating costs/gains for extracting tradable goods and services) and novel second-tier instruments (new/expanded monetary tools developed as by-products of reef restoration measures). The emerging new suite of economic mechanisms based on restoration methodologies could be served as an incentive for ecosystem conservation, enhancing the sum values of all services generated by coral reefs, where the same stocks of farmed/transplanted coral colonies will be used as market instruments. I found that active restoration measures disclose 12 classes of second-tier goods and services, which may partly/wholly finance restoration acts, bringing to light reef capitalizations that allow the expansion of markets with products that have not been considered before. The degree to which the second tier of market-related services could buffer coral-reef degradation is still unclear and would vary with different reef types and in various reef restoration scenarios; however, reducing the uncertainty associated with restoration. It is expected that the expansion of markets with the new products and the enhancement of those already existing will be materialized even if reef ecosystems will recover into different statuses.

  14. Coral Dominance”: A Dangerous Ecosystem Misnomer?

    Directory of Open Access Journals (Sweden)

    Peter S. Vroom

    2011-01-01

    Full Text Available Over 100 years ago, before threats such as global climate change and ocean acidification were issues engrossing marine scientists, numerous tropical reef biologists began expressing concern that too much emphasis was being placed on coral dominance in reef systems. These researchers believed that the scientific community was beginning to lose sight of the overall mix of calcifying organisms necessary for the healthy function of reef ecosystems and demonstrated that some reefs were naturally coral dominated with corals being the main organisms responsible for reef accretion, yet other healthy reef ecosystems were found to rely almost entirely on calcified algae and foraminifera for calcium carbonate accumulation. Despite these historical cautionary messages, many agencies today have inherited a coral-centric approach to reef management, likely to the detriment of reef ecosystems worldwide. For example, recent research has shown that crustose coralline algae, a group of plants essential for building and cementing reef systems, are in greater danger of exhibiting decreased calcification rates and increased solubility than corals in warmer and more acidic ocean environments. A shift from coral-centric views to broader ecosystem views is imperative in order to protect endangered reef systems worldwide.

  15. Variability in reef connectivity in the Coral Triangle

    Science.gov (United States)

    Thompson, D. M.; Kleypas, J. A.; Castruccio, F. S.; Watson, J. R.; Curchitser, E. N.

    2015-12-01

    The Coral Triangle (CT) is not only the global center of marine biodiversity, it also supports the livelihoods of millions of people. Unfortunately, it is also considered the most threatened of all reef regions, with rising temperature and coral bleaching already taking a toll. Reproductive connectivity between reefs plays a critical role in the reef's capacity to recover after such disturbances. Thus, oceanographic modeling efforts to understand patterns of reef connectivity are essential to the effective design of a network of Marine Protected Areas (MPAs) to conserve marine ecosystems in the Coral Triangle. Here, we combine a Regional Ocean Modeling System developed for the Coral Triangle (CT-ROMS) with a Lagrangian particle tracking tool (TRACMASS) to investigate the probability of coral larval transport between reefs. A 47-year hindcast simulation (1960-2006) was used to investigate the variability in larval transport of a broadcasting coral following mass spawning events in April and September. Potential connectivity between reefs was highly variable and stochastic from year to year, emphasizing the importance of decadal or longer simulations in identifying connectivity patterns, key source and sink regions, and thus marine management targets for MPAs. The influence of temperature on realized connectivity (future work) may add further uncertainty to year-to-year patterns of connectivity between reefs. Nonetheless, the potential connectivity results we present here suggest that although reefs in this region are primarily self-seeded, rare long-distance dispersal may promote recovery and genetic exchange between reefs in the region. The spatial pattern of "subpopulations" based solely on the physical drivers of connectivity between reefs closely match regional patterns of biodiversity, suggesting that physical barriers to larval dispersal may be a key driver of reef biodiversity. Finally, 21st Century simulations driven by the Community Earth System Model (CESM

  16. Quantifying water flow within aquatic ecosystems using load cell sensors: a profile of currents experienced by coral reef organisms around Lizard Island, Great Barrier Reef, Australia.

    Science.gov (United States)

    Johansen, Jacob L

    2014-01-01

    Current velocity in aquatic environments has major implications for the diversity, abundance and ecology of aquatic organisms, but quantifying these currents has proven difficult. This study utilises a simple and inexpensive instrument (reef system around Lizard Island (Great Barrier Reef, Australia) at a spatial and temporal scale relevant to the ecology of individual benthos and fish. The instrument uses load-cell sensors to provide a correlation between sensor output and ambient current velocity of 99%. Each instrument is able to continuously record current velocities to >500 cms⁻¹ and wave frequency to >100 Hz over several weeks. Sensor data are registered and processed at 16 MHz and 10 bit resolution, with a measuring precision of 0.06±0.04%, and accuracy of 0.51±0.65% (mean ±S.D.). Each instrument is also pressure rated to 120 m and shear stresses ≤20 kNm⁻² allowing deployment in harsh environments. The instrument was deployed across 27 coral reef sites covering the crest (3 m), mid-slope (6 m) and deep-slope (9 m depth) of habitats directly exposed, oblique or sheltered from prevailing winds. Measurements demonstrate that currents over the reef slope and crest varies immensely depending on depth and exposure: currents differ up to 9-fold within habitats only separated by 3 m depth and 15-fold between exposed, oblique and sheltered habitats. Comparisons to ambient weather conditions reveal that currents around Lizard Island are largely wind driven. Zero to 22.5 knot winds correspond directly to currents of 0 to >82 cms⁻¹, while tidal currents rarely exceed 5.5 cms⁻¹. Rather, current velocity increases exponentially as a function of wave height (0 to 1.6 m) and frequency (0.54 to 0.20 Hz), emphasizing the enormous effect of wind and waves on organisms in these shallow coral reef habitats.

  17. Avoiding coral reef functional collapse requires local and global action.

    Science.gov (United States)

    Kennedy, Emma V; Perry, Chris T; Halloran, Paul R; Iglesias-Prieto, Roberto; Schönberg, Christine H L; Wisshak, Max; Form, Armin U; Carricart-Ganivet, Juan P; Fine, Maoz; Eakin, C Mark; Mumby, Peter J

    2013-05-20

    Coral reefs face multiple anthropogenic threats, from pollution and overfishing to the dual effects of greenhouse gas emissions: rising sea temperature and ocean acidification. While the abundance of coral has declined in recent decades, the implications for humanity are difficult to quantify because they depend on ecosystem function rather than the corals themselves. Most reef functions and ecosystem services are founded on the ability of reefs to maintain their three-dimensional structure through net carbonate accumulation. Coral growth only constitutes part of a reef's carbonate budget; bioerosion processes are influential in determining the balance between net structural growth and disintegration. Here, we combine ecological models with carbonate budgets and drive the dynamics of Caribbean reefs with the latest generation of climate models. Budget reconstructions using documented ecological perturbations drive shallow (6-10 m) Caribbean forereefs toward an increasingly fragile carbonate balance. We then projected carbonate budgets toward 2080 and contrasted the benefits of local conservation and global action on climate change. Local management of fisheries (specifically, no-take marine reserves) and the watershed can delay reef loss by at least a decade under "business-as-usual" rises in greenhouse gas emissions. However, local action must be combined with a low-carbon economy to prevent degradation of reef structures and associated ecosystem services. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Climate-driven coral reorganisation influences aggressive behaviour in juvenile coral-reef fishes

    OpenAIRE

    Kok, Judith E.; Graham, Nicholas Anthony James; Mia O Hoogenboom

    2016-01-01

    Globally, habitat degradation is altering the abundance and diversity of species in a variety of ecosystems. This study aimed to determine how habitat degradation, in terms of changing coral composition under climate change, affected abundance, species richness and aggressive behaviour of juveniles of three damselfishes (Pomacentrus moluccensis, P. amboinensis and Dischistodus perspicillatus, in order of decreasing reliance on coral). Patch reefs were constructed to simulate two types of reef...

  19. The functioning of coral reef communities along environmental gradients

    OpenAIRE

    Plass-Johnson, Jeremiah

    2015-01-01

    One of the primary challenges in ecology is to understand how environmental disturbance affects diversity and community structure, and what are the subsequent consequences on ecosystem functioning. Coral reefs are some of the most diverse ecosystems on the planet resulting in complex sets of interactions between benthic, habitat-forming constituents and mobile fish consumers. However, scleractinian corals, the primary habitat engineers, are dependent on high-light, low-nutrient water conditio...

  20. Coral Reef Watch, Hotspots, 50 km

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Coral Reef Watch provides Coral Bleaching hotspot maps derived from NOAA's Polar Operational Environmental Satellites (POES). This data provides global area...

  1. Global warming and coral reefs

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.

    photosynthesis and survival of coral planulae, etc. Unfortunately, no such studies have been carried out on Indian corals so far, and a visualization of what will happen to Indian reefs if sea level rises rapidly will have to be constructed based on such dat... susceptible, as plankton living near the sea surface, and as hosts deriving nutri tional benefits from zooxanthtllar photosynthesis, which itself is susceptible to UV-B damage. Contrary to the misconception that UV is absorbed by the sea water, UV penetrates...

  2. Coral Reef Color: Remote and In-Situ Imaging Spectroscopy of Reef Structure and Function

    Science.gov (United States)

    Hochberg, E. J.

    2015-12-01

    Coral reefs are threatened at local to global scales by a litany of anthropogenic impacts, including overfishing, coastal development, marine and watershed pollution, rising ocean temperatures, and ocean acidification. However, available data for the primary indicator of coral reef condition — proportional cover of living coral — are surprisingly sparse and show patterns that contradict the prevailing understanding of how environment impacts reef condition. Remote sensing is the only available tool for acquiring synoptic, uniform data on reef condition at regional to global scales. Discrimination between coral and other reef benthos relies on narrow wavebands afforded by imaging spectroscopy. The same spectral information allows non-invasive quantification of photosynthetic pigment composition, which shows unexpected phenological trends. There is also potential to link biodiversity with optical diversity, though there has been no effort in that direction. Imaging spectroscopy underlies the light-use efficiency model for reef primary production by quantifying light capture, which in turn indicates biochemical capacity for CO2 assimilation. Reef calcification is strongly correlated with primary production, suggesting the possibility for an optics-based model of that aspect of reef function, as well. By scaling these spectral models for use with remote sensing, we can vastly improve our understanding of reef structure, function, and overall condition across regional to global scales. By analyzing those remote sensing products against ancillary environmental data, we can construct secondary models to predict reef futures in the era of global change. This final point is the objective of CORAL (COral Reef Airborne Laboratory), a three-year project funded under NASA's Earth Venture Suborbital-2 program to investigate the relationship between coral reef condition at the ecosystem scale and various nominal biogeophysical forcing parameters.

  3. Florida Integrated Science Center (FISC) Coral Reef Research

    Science.gov (United States)

    Poore, D.Z.

    2008-01-01

    Coral reefs provide important ecosystem services such as shoreline protection and the support of lucrative industries including fisheries and tourism. Such ecosystem services are being compromised as reefs decline due to coral disease, climate change, overfishing, and pollution. There is a need for focused, integrated science to understand the complex ecological interactions and effects of these many stressors and to provide information that will effectively guide policies and best management practices to preserve and restore these important resources. The U.S. Geological Survey Florida Integrated Science Center (USGS-FISC) is conducting a coordinated Coral Reef Research Project beginning in 2009. Specific research topics are aimed at addressing priorities identified in the 'Strategic Science for Coral Ecosystems 2007-2011' document (U.S. Geological Survey, 2007). Planned research will include a blend of historical, monitoring, and process studies aimed at improving our understanding of the development, current status and function, and likely future changes in coral ecosystems. Topics such as habitat characterization and distribution, coral disease, and trends in biogenic calcification are major themes of understanding reef structure, ecological integrity, and responses to global change.

  4. Embracing a world of subtlety and nuance on coral reefs

    Science.gov (United States)

    Mumby, Peter J.

    2017-09-01

    Climate change will homogenise the environment and generate a preponderance of mediocre reefs. Managing seascapes of mediocrity will be challenging because our science is ill prepared to deal with the `shades of grey' of reef health; we tend to study natural processes in the healthiest reefs available. Yet much can be gained by examining the drivers and implications of even subtle changes in reef state. Where strong ecological interactions are discovered, even small changes in abundance can have profound impacts on coral resilience. Indeed, if we are to develop effective early warnings of critical losses of resilience, then monitoring must place greater emphasis on measuring and interpreting changes in reef recovery rates. In terms of mechanism, a more nuanced approach is needed to explore the generality of what might be considered `dogma'. A more nuanced approach to science will serve managers needs well and help minimise the rise of mediocrity in coral reef ecosystems.

  5. Spatial and temporal behavior and acute ecotoxicological effects of Tributyltin (TBT) on coral reef and adjacent ecosystems around Okinawa Island, Japan.

    Science.gov (United States)

    Sheikh, M. A.; Higuchi, T.; Imo, T. S.; Fujimura, H.; Oomori, T.

    2007-12-01

    Spatial and temporal behavior of the tributyl tin (TBT) were investigated in the coastal areas around Okinawa Island, Japan. A seasonal monitoring study was conducted between February and October 2006. The effects of TBT on the carbon metabolisms (net production and calcification) on the intact coral-alga association Galaxea fascicularis were also investigated. Mean concentration of TBT (2.45 ng/L) found in the Manko estuary waters have exceeded some international permissible targets of waters quality guideline for TBT (1ng/L). The sediments in Manko estuary sediments can be considered lightly contaminated (0-20 ng/g dw) and Okukubi estuary as uncontaminated (below 3ng/g dw) with TBT. The seasonal concentration pattern of TBT at the Manko estuary was autumn > spring > summer > winter. The acute ecotoxicological results show that the photosynthesis rate and calcification rate were significantly reduced by 78 % and 72 % relative to the control (ANOVA, p0.05) were observed when corals were exposed to 1000 ng/LTBT. The present study reports the occurrence and continuous input of TBT in the coastal areas around Okinawa Island, even 16 years after legal restriction of TBT usage in coastal waters was implemented by the Japanese Environmental Authorities. However, the nominal sensitive concentration of TBT that causes alteration of carbon metabolisms of coral within 96 hrs exposure are much higher than those recently found in the coral reef waters and adjacent ecosystems.

  6. Persistence and change in community composition of reef corals through present, past, and future climates.

    Science.gov (United States)

    Edmunds, Peter J; Adjeroud, Mehdi; Baskett, Marissa L; Baums, Iliana B; Budd, Ann F; Carpenter, Robert C; Fabina, Nicholas S; Fan, Tung-Yung; Franklin, Erik C; Gross, Kevin; Han, Xueying; Jacobson, Lianne; Klaus, James S; McClanahan, Tim R; O'Leary, Jennifer K; van Oppen, Madeleine J H; Pochon, Xavier; Putnam, Hollie M; Smith, Tyler B; Stat, Michael; Sweatman, Hugh; van Woesik, Robert; Gates, Ruth D

    2014-01-01

    The reduction in coral cover on many contemporary tropical reefs suggests a different set of coral community assemblages will dominate future reefs. To evaluate the capacity of reef corals to persist over various time scales, we examined coral community dynamics in contemporary, fossil, and simulated future coral reef ecosystems. Based on studies between 1987 and 2012 at two locations in the Caribbean, and between 1981 and 2013 at five locations in the Indo-Pacific, we show that many coral genera declined in abundance, some showed no change in abundance, and a few coral genera increased in abundance. Whether the abundance of a genus declined, increased, or was conserved, was independent of coral family. An analysis of fossil-reef communities in the Caribbean revealed changes in numerical dominance and relative abundances of coral genera, and demonstrated that neither dominance nor taxon was associated with persistence. As coral family was a poor predictor of performance on contemporary reefs, a trait-based, dynamic, multi-patch model was developed to explore the phenotypic basis of ecological performance in a warmer future. Sensitivity analyses revealed that upon exposure to thermal stress, thermal tolerance, growth rate, and longevity were the most important predictors of coral persistence. Together, our results underscore the high variation in the rates and direction of change in coral abundances on contemporary and fossil reefs. Given this variation, it remains possible that coral reefs will be populated by a subset of the present coral fauna in a future that is warmer than the recent past.

  7. Thresholds and the resilience of Caribbean coral reefs.

    Science.gov (United States)

    Mumby, Peter J; Hastings, Alan; Edwards, Helen J

    2007-11-01

    The deteriorating health of the world's coral reefs threatens global biodiversity, ecosystem function, and the livelihoods of millions of people living in tropical coastal regions. Reefs in the Caribbean are among the most heavily affected, having experienced mass disease-induced mortality of the herbivorous urchin Diadema antillarum in 1983 and two framework-building species of coral. Declining reef health is characterized by increases in macroalgae. A critical question is whether the observed macroalgal bloom on Caribbean reefs is easily reversible. To answer this question, we must resolve whether algal-dominated reefs are an alternative stable state of the ecosystem or simply the readily reversible result of a phase change along a gradient of some environmental or ecological parameter. Here, using a fully parameterized simulation model in combination with a simple analytical model, we show that Caribbean reefs became susceptible to alternative stable states once the urchin mortality event of 1983 confined the majority of grazing to parrotfishes. We reveal dramatic hysteresis in a natural system and define critical thresholds of grazing and coral cover beyond which resilience is lost. Most grazing thresholds lie near the upper level observed for parrotfishes in nature, suggesting that reefs are highly sensitive to parrotfish exploitation. Ecosystem thresholds can be combined with stochastic models of disturbance to identify targets for the restoration of ecosystem processes. We illustrate this principle by estimating the relationship between current reef state (coral cover and grazing) and the probability that the reef will withstand moderate hurricane intensity for two decades without becoming entrained in a shift towards a stable macroalgal-dominated state. Such targets may help reef managers face the challenge of addressing global disturbance at local scales.

  8. Coral settlement on a highly disturbed equatorial reef system.

    Science.gov (United States)

    Bauman, Andrew G; Guest, James R; Dunshea, Glenn; Low, Jeffery; Todd, Peter A; Steinberg, Peter D

    2015-01-01

    Processes occurring early in the life stages of corals can greatly influence the demography of coral populations, and successful settlement of coral larvae that leads to recruitment is a critical life history stage for coral reef ecosystems. Although corals in Singapore persist in one the world's most anthropogenically impacted reef systems, our understanding of the role of coral settlement in the persistence of coral communities in Singapore remains limited. Spatial and temporal patterns of coral settlement were examined at 7 sites in the southern islands of Singapore, using settlement tiles deployed and collected every 3 months from 2011 to 2013. Settlement occurred year round, but varied significantly across time and space. Annual coral settlement was low (~54.72 spat m(-2) yr(-1)) relative to other equatorial regions, but there was evidence of temporal variation in settlement rates. Peak settlement occurred between March-May and September-November, coinciding with annual coral spawning periods (March-April and October), while the lowest settlement occurred from December-February during the northeast monsoon. A period of high settlement was also observed between June and August in the first year (2011/12), possibly due to some species spawning outside predicted spawning periods, larvae settling from other locations or extended larval settlement competency periods. Settlement rates varied significantly among sites, but spatial variation was relatively consistent between years, suggesting the strong effects of local coral assemblages or environmental conditions. Pocilloporidae were the most abundant coral spat (83.6%), while Poritidae comprised only 6% of the spat, and Acroporidae coral spat. These results indicate that current settlement patterns are reinforcing the local adult assemblage structure ('others'; i.e. sediment-tolerant coral taxa) in Singapore, but that the replenishment capacity of Singapore's reefs appears relatively constrained, which could lead

  9. Coral settlement on a highly disturbed equatorial reef system.

    Directory of Open Access Journals (Sweden)

    Andrew G Bauman

    Full Text Available Processes occurring early in the life stages of corals can greatly influence the demography of coral populations, and successful settlement of coral larvae that leads to recruitment is a critical life history stage for coral reef ecosystems. Although corals in Singapore persist in one the world's most anthropogenically impacted reef systems, our understanding of the role of coral settlement in the persistence of coral communities in Singapore remains limited. Spatial and temporal patterns of coral settlement were examined at 7 sites in the southern islands of Singapore, using settlement tiles deployed and collected every 3 months from 2011 to 2013. Settlement occurred year round, but varied significantly across time and space. Annual coral settlement was low (~54.72 spat m(-2 yr(-1 relative to other equatorial regions, but there was evidence of temporal variation in settlement rates. Peak settlement occurred between March-May and September-November, coinciding with annual coral spawning periods (March-April and October, while the lowest settlement occurred from December-February during the northeast monsoon. A period of high settlement was also observed between June and August in the first year (2011/12, possibly due to some species spawning outside predicted spawning periods, larvae settling from other locations or extended larval settlement competency periods. Settlement rates varied significantly among sites, but spatial variation was relatively consistent between years, suggesting the strong effects of local coral assemblages or environmental conditions. Pocilloporidae were the most abundant coral spat (83.6%, while Poritidae comprised only 6% of the spat, and Acroporidae <1%. Other, unidentifiable families represented 10% of the coral spat. These results indicate that current settlement patterns are reinforcing the local adult assemblage structure ('others'; i.e. sediment-tolerant coral taxa in Singapore, but that the replenishment capacity

  10. Virus-host interactions and their roles in coral reef health and disease.

    Science.gov (United States)

    Thurber, Rebecca Vega; Payet, Jérôme P; Thurber, Andrew R; Correa, Adrienne M S

    2017-04-01

    Coral reefs occur in nutrient-poor shallow waters, constitute biodiversity and productivity hotspots, and are threatened by anthropogenic disturbance. This Review provides an introduction to coral reef virology and emphasizes the links between viruses, coral mortality and reef ecosystem decline. We describe the distinctive benthic-associated and water-column- associated viromes that are unique to coral reefs, which have received less attention than viruses in open-ocean systems. We hypothesize that viruses of bacteria and eukaryotes dynamically interact with their hosts in the water column and with scleractinian (stony) corals to influence microbial community dynamics, coral bleaching and disease, and reef biogeochemical cycling. Last, we outline how marine viruses are an integral part of the reef system and suggest that the influence of viruses on reef function is an essential component of these globally important environments.

  11. Acoustical Measurement and Biot Model for Coral Reef Detection and Quantification

    Directory of Open Access Journals (Sweden)

    Henry M. Manik

    2016-01-01

    Full Text Available Coral reefs are coastal resources and very useful for marine ecosystems. Nowadays, the existence of coral reefs is seriously threatened due to the activities of blast fishing, coral mining, marine sedimentation, pollution, and global climate change. To determine the existence of coral reefs, it is necessary to study them comprehensively. One method to study a coral reef by using a propagation of sound waves is proposed. In this research, the measurement of reflection coefficient, transmission coefficient, acoustic backscattering, hardness, and roughness of coral reefs has been conducted using acoustic instruments and numerical modeling using Biot theory. The results showed that the quantification of the acoustic backscatter can classify the type of coral reef.

  12. Prioritizing land and sea conservation investments to protect coral reefs.

    Directory of Open Access Journals (Sweden)

    Carissa J Klein

    Full Text Available BACKGROUND: Coral reefs have exceptional biodiversity, support the livelihoods of millions of people, and are threatened by multiple human activities on land (e.g. farming and in the sea (e.g. overfishing. Most conservation efforts occur at local scales and, when effective, can increase the resilience of coral reefs to global threats such as climate change (e.g. warming water and ocean acidification. Limited resources for conservation require that we efficiently prioritize where and how to best sustain coral reef ecosystems. METHODOLOGY/PRINCIPAL FINDINGS: Here we develop the first prioritization approach that can guide regional-scale conservation investments in land- and sea-based conservation actions that cost-effectively mitigate threats to coral reefs, and apply it to the Coral Triangle, an area of significant global attention and funding. Using information on threats to marine ecosystems, effectiveness of management actions at abating threats, and the management and opportunity costs of actions, we calculate the rate of return on investment in two conservation actions in sixteen ecoregions. We discover that marine conservation almost always trumps terrestrial conservation within any ecoregion, but terrestrial conservation in one ecoregion can be a better investment than marine conservation in another. We show how these results could be used to allocate a limited budget for conservation and compare them to priorities based on individual criteria. CONCLUSIONS/SIGNIFICANCE: Previous prioritization approaches do not consider both land and sea-based threats or the socioeconomic costs of conserving coral reefs. A simple and transparent approach like ours is essential to support effective coral reef conservation decisions in a large and diverse region like the Coral Triangle, but can be applied at any scale and to other marine ecosystems.

  13. Prioritizing land and sea conservation investments to protect coral reefs.

    Science.gov (United States)

    Klein, Carissa J; Ban, Natalie C; Halpern, Benjamin S; Beger, Maria; Game, Edward T; Grantham, Hedley S; Green, Alison; Klein, Travis J; Kininmonth, Stuart; Treml, Eric; Wilson, Kerrie; Possingham, Hugh P

    2010-08-30

    Coral reefs have exceptional biodiversity, support the livelihoods of millions of people, and are threatened by multiple human activities on land (e.g. farming) and in the sea (e.g. overfishing). Most conservation efforts occur at local scales and, when effective, can increase the resilience of coral reefs to global threats such as climate change (e.g. warming water and ocean acidification). Limited resources for conservation require that we efficiently prioritize where and how to best sustain coral reef ecosystems. Here we develop the first prioritization approach that can guide regional-scale conservation investments in land- and sea-based conservation actions that cost-effectively mitigate threats to coral reefs, and apply it to the Coral Triangle, an area of significant global attention and funding. Using information on threats to marine ecosystems, effectiveness of management actions at abating threats, and the management and opportunity costs of actions, we calculate the rate of return on investment in two conservation actions in sixteen ecoregions. We discover that marine conservation almost always trumps terrestrial conservation within any ecoregion, but terrestrial conservation in one ecoregion can be a better investment than marine conservation in another. We show how these results could be used to allocate a limited budget for conservation and compare them to priorities based on individual criteria. Previous prioritization approaches do not consider both land and sea-based threats or the socioeconomic costs of conserving coral reefs. A simple and transparent approach like ours is essential to support effective coral reef conservation decisions in a large and diverse region like the Coral Triangle, but can be applied at any scale and to other marine ecosystems.

  14. Can we measure beauty? Computational evaluation of coral reef aesthetics

    Directory of Open Access Journals (Sweden)

    Andreas F. Haas

    2015-11-01

    Full Text Available The natural beauty of coral reefs attracts millions of tourists worldwide resulting in substantial revenues for the adjoining economies. Although their visual appearance is a pivotal factor attracting humans to coral reefs current monitoring protocols exclusively target biogeochemical parameters, neglecting changes in their aesthetic appearance. Here we introduce a standardized computational approach to assess coral reef environments based on 109 visual features designed to evaluate the aesthetic appearance of art. The main feature groups include color intensity and diversity of the image, relative size, color, and distribution of discernable objects within the image, and texture. Specific coral reef aesthetic values combining all 109 features were calibrated against an established biogeochemical assessment (NCEAS using machine learning algorithms. These values were generated for ∼2,100 random photographic images collected from 9 coral reef locations exposed to varying levels of anthropogenic influence across 2 ocean systems. Aesthetic values proved accurate predictors of the NCEAS scores (root mean square error < 5 for N ≥ 3 and significantly correlated to microbial abundance at each site. This shows that mathematical approaches designed to assess the aesthetic appearance of photographic images can be used as an inexpensive monitoring tool for coral reef ecosystems. It further suggests that human perception of aesthetics is not purely subjective but influenced by inherent reactions towards measurable visual cues. By quantifying aesthetic features of coral reef systems this method provides a cost efficient monitoring tool that targets one of the most important socioeconomic values of coral reefs directly tied to revenue for its local population.

  15. The growth of coral reef science in the Gulf: a historical perspective.

    Science.gov (United States)

    Burt, John A

    2013-07-30

    Coral reef science has grown exponentially in recent decades in the Gulf. Analysis of literature from 1950 to 2012 identified 270 publications on coral reefs in the Gulf, half of which were published in just the past decade. This paper summarizes the growth and evolution of coral reef science in the Gulf by examining when, where and how research has been conducted on Gulf reefs, who conducted that research, and what themes and taxa have dominated scientific interest. The results demonstrate that there has been significant growth in our understanding of the valuable coral reefs of the Gulf, but also highlight the fact that we are documenting an increasingly degraded ecosystem. Reef scientists must make a concerted effort to improve dialogue with regional reef management and decision-makers if we are to stem the tide of decline in coral reefs in the Gulf. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Forest conservation delivers highly variable coral reef conservation outcomes.

    Science.gov (United States)

    Klein, Carissa J; Jupiter, Stacy D; Selig, Elizabeth R; Watts, Matthew E; Halpern, Benjamin S; Kamal, Muhammad; Roelfsema, Chris; Possingham, Hugh P

    2012-06-01

    Coral reefs are threatened by human activities on both the land (e.g., deforestation) and the sea (e.g., overfishing). Most conservation planning for coral reefs focuses on removing threats in the sea, neglecting management actions on the land. A more integrated approach to coral reef conservation, inclusive of land-sea connections, requires an understanding of how and where terrestrial conservation actions influence reefs. We address this by developing a land-sea planning approach to inform fine-scale spatial management decisions and test it in Fiji. Our aim is to determine where the protection of forest can deliver the greatest return on investment for coral reef ecosystems. To assess the benefits of conservation to coral reefs, we estimate their relative condition as influenced by watershed-based pollution and fishing. We calculate the cost-effectiveness of protecting forest and find that investments deliver rapidly diminishing returns for improvements to relative reef condition. For example, protecting 2% of forest in one area is almost 500 times more beneficial than protecting 2% in another area, making prioritization essential. For the scenarios evaluated, relative coral reef condition could be improved by 8-58% if all remnant forest in Fiji were protected rather than deforested. Finally, we determine the priority of each coral reef for implementing a marine protected area when all remnant forest is protected for conservation. The general results will support decisions made by the Fiji Protected Area Committee as they establish a national protected area network that aims to protect 20% of the land and 30% of the inshore waters by 2020. Although challenges remain, we can inform conservation decisions around the globe by tackling the complex issues relevant to integrated land-sea planning.

  17. Nitrification in reef corals

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.; Wafar, S.; David, J.J.

    cells cmP2 (Drew 1972), it is reasonable to expect that nitrification will have to compete with assimilatory re- moval of NH,+. The relative importance of NH4+ flux in these two pathways can be evaluated with the present data on NO,- production... about the means in the es- timates, this correspondence shows that bacterial nitrification effectively competes with autotrophic uptake of NH,+ in coral- zooxanthellae symbiosis. In fact, our nitrification rates would be underestimates since losses...

  18. Sewage impacts coral reefs at multiple levels of ecological organization.

    Science.gov (United States)

    Reopanichkul, Pasinee; Schlacher, Thomas A; Carter, R W; Worachananant, Suchai

    2009-09-01

    Against a backdrop of rising sea temperatures and ocean acidification which pose global threats to coral reefs, excess nutrients and turbidity continue to be significant stressors at regional and local scales. Because interventions usually require local data on pollution impacts, we measured ecological responses to sewage discharges in Surin Marine Park, Thailand. Wastewater disposal significantly increased inorganic nutrients and turbidity levels, and this degradation in water quality resulted in substantial ecological shifts in the form of (i) increased macroalgal density and species richness, (ii) lower cover of hard corals, and (iii) significant declines in fish abundance. Thus, the effects of nutrient pollution and turbidity can cascade across several levels of ecological organization to change key properties of the benthos and fish on coral reefs. Maintenance or restoration of ecological reef health requires improved wastewater management and run-off control for reefs to deliver their valuable ecosystems services.

  19. A unified model explains commonness and rarity on coral reefs.

    Science.gov (United States)

    Connolly, Sean R; Hughes, Terry P; Bellwood, David R

    2017-04-01

    Abundance patterns in ecological communities have important implications for biodiversity maintenance and ecosystem functioning. However, ecological theory has been largely unsuccessful at capturing multiple macroecological abundance patterns simultaneously. Here, we propose a parsimonious model that unifies widespread ecological relationships involving local aggregation, species-abundance distributions, and species associations, and we test this model against the metacommunity structure of reef-building corals and coral reef fishes across the western and central Pacific. For both corals and fishes, the unified model simultaneously captures extremely well local species-abundance distributions, interspecific variation in the strength of spatial aggregation, patterns of community similarity, species accumulation, and regional species richness, performing far better than alternative models also examined here and in previous work on coral reefs. Our approach contributes to the development of synthetic theory for large-scale patterns of community structure in nature, and to addressing ongoing challenges in biodiversity conservation at macroecological scales.

  20. Crustose coralline algae increased framework and diversity on ancient coral reefs.

    Science.gov (United States)

    Weiss, Anna; Martindale, Rowan C

    2017-01-01

    Crustose coralline algae (CCA) are key producers of carbonate sediment on reefs today. Despite their importance in modern reef ecosystems, the long-term relationship of CCA with reef development has not been quantitatively assessed in the fossil record. This study includes data from 128 Cenozoic coral reefs collected from the Paleobiology Database, the Paleoreefs Database, as well as the original literature and assesses the correlation of CCA abundance with taxonomic diversity (both corals and reef dwellers) and framework of fossil coral reefs. Chi-squared tests show reef type is significantly correlated with CCA abundance and post-hoc tests indicate higher involvement of CCA is associated with stronger reef structure. Additionally, general linear models show coral reefs with higher amounts of CCA had a higher diversity of reef-dwelling organisms. These data have important implications for paleoecology as they demonstrate that CCA increased building capacity, structural integrity, and diversity of ancient coral reefs. The analyses presented here demonstrate that the function of CCA on modern coral reefs is similar to their function on Cenozoic reefs; thus, studies of ancient coral reef collapse are even more meaningful as modern analogues.

  1. Quantifying water flow within aquatic ecosystems using load cell sensors: a profile of currents experienced by coral reef organisms around Lizard Island, Great Barrier Reef, Australia.

    Directory of Open Access Journals (Sweden)

    Jacob L Johansen

    Full Text Available Current velocity in aquatic environments has major implications for the diversity, abundance and ecology of aquatic organisms, but quantifying these currents has proven difficult. This study utilises a simple and inexpensive instrument (500 cms⁻¹ and wave frequency to >100 Hz over several weeks. Sensor data are registered and processed at 16 MHz and 10 bit resolution, with a measuring precision of 0.06±0.04%, and accuracy of 0.51±0.65% (mean ±S.D.. Each instrument is also pressure rated to 120 m and shear stresses ≤20 kNm⁻² allowing deployment in harsh environments. The instrument was deployed across 27 coral reef sites covering the crest (3 m, mid-slope (6 m and deep-slope (9 m depth of habitats directly exposed, oblique or sheltered from prevailing winds. Measurements demonstrate that currents over the reef slope and crest varies immensely depending on depth and exposure: currents differ up to 9-fold within habitats only separated by 3 m depth and 15-fold between exposed, oblique and sheltered habitats. Comparisons to ambient weather conditions reveal that currents around Lizard Island are largely wind driven. Zero to 22.5 knot winds correspond directly to currents of 0 to >82 cms⁻¹, while tidal currents rarely exceed 5.5 cms⁻¹. Rather, current velocity increases exponentially as a function of wave height (0 to 1.6 m and frequency (0.54 to 0.20 Hz, emphasizing the enormous effect of wind and waves on organisms in these shallow coral reef habitats.

  2. 78 FR 67128 - Coral Reef Conservation Program; Meeting

    Science.gov (United States)

    2013-11-08

    ... National Oceanic and Atmospheric Administration Coral Reef Conservation Program; Meeting AGENCY: Coral Reef... of public comment. SUMMARY: Notice is hereby given of a public meeting of the U.S. Coral Reef Task... to do so. Established by Presidential Executive Order 13089 in 1998, the U.S. Coral Reef Task Force...

  3. Hysteresis in coral reefs under macroalgal toxicity and overfishing.

    Science.gov (United States)

    Bhattacharyya, Joydeb; Pal, Samares

    2015-03-01

    Macroalgae and corals compete for the available space in coral reef ecosystems.While herbivorous reef fish play a beneficial role in decreasing the growth of macroalgae, macroalgal toxicity and overfishing of herbivores leads to proliferation of macroalgae. The abundance of macroalgae changes the community structure towards a macroalgae-dominated reef ecosystem. We investigate coral-macroalgal phase shifts by means of a continuous time model in a food chain. Conditions for local asymptotic stability of steady states are derived. It is observed that in the presence of macroalgal toxicity and overfishing, the system exhibits hysteresis through saddle-node bifurcation and transcritical bifurcation. We examine the effects of time lags in the liberation of toxins by macroalgae and the recovery of algal turf in response to grazing of herbivores on macroalgae by performing equilibrium and stability analyses of delay-differential forms of the ODE model. Computer simulations have been carried out to illustrate the different analytical results.

  4. National Coral Reef Monitoring Program: Assessment of coral reef communities in Puerto Rico using the Coral Demographics method

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coral Demographic method is one of two benthic surveys conducted in Puerto Rico as part of the National Coral Reef Monitoring Program (NCRMP). The coral...

  5. Groundtruthing Notes and Miscellaneous Biological Datasets from Coral Ecosystems Surveys from the Northwestern Hawaiian Islands Rapid Reef Assessment and Monitoring Program of 2000-2002 (NODC Accession 0001448)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Northwestern Hawaiian Islands Coral Reef Assessment and Monitoring Program (NOWRAMP) began in 2000 with the mission to rapidly evaluate and map the shallow water...

  6. Herbivore space use influences coral reef recovery.

    Science.gov (United States)

    Eynaud, Yoan; McNamara, Dylan E; Sandin, Stuart A

    2016-06-01

    Herbivores play an important role in marine communities. On coral reefs, the diversity and unique feeding behaviours found within this functional group can have a comparably diverse set of impacts in structuring the benthic community. Here, using a spatially explicit model of herbivore foraging, we explore how the spatial pattern of grazing behaviours impacts the recovery of a reef ecosystem, considering movements at two temporal scales-short term (e.g. daily foraging patterns) and longer term (e.g. monthly movements across the landscape). Model simulations suggest that more spatially constrained herbivores are more effective at conferring recovery capability by providing a favourable environment to coral recruitment and growth. Results also show that the composition of food available to the herbivore community is linked directly to the pattern of space use by herbivores. To date, most studies of variability among the impacts of herbivore species have considered the diversity of feeding modes and mouthparts. Our work provides a complementary view of spatial patterns of foraging, revealing that variation in movement behaviours alone can affect patterns of benthic change, and thus broadens our view of realized links between herbivore diversity and reef recovery.

  7. Herbivore space use influences coral reef recovery

    Science.gov (United States)

    Eynaud, Yoan; McNamara, Dylan E.; Sandin, Stuart A.

    2016-01-01

    Herbivores play an important role in marine communities. On coral reefs, the diversity and unique feeding behaviours found within this functional group can have a comparably diverse set of impacts in structuring the benthic community. Here, using a spatially explicit model of herbivore foraging, we explore how the spatial pattern of grazing behaviours impacts the recovery of a reef ecosystem, considering movements at two temporal scales—short term (e.g. daily foraging patterns) and longer term (e.g. monthly movements across the landscape). Model simulations suggest that more spatially constrained herbivores are more effective at conferring recovery capability by providing a favourable environment to coral recruitment and growth. Results also show that the composition of food available to the herbivore community is linked directly to the pattern of space use by herbivores. To date, most studies of variability among the impacts of herbivore species have considered the diversity of feeding modes and mouthparts. Our work provides a complementary view of spatial patterns of foraging, revealing that variation in movement behaviours alone can affect patterns of benthic change, and thus broadens our view of realized links between herbivore diversity and reef recovery. PMID:27429784

  8. Trade-offs between data resolution, accuracy, and cost when choosing information to plan reserves for coral reef ecosystems.

    Science.gov (United States)

    Tulloch, Vivitskaia J; Klein, Carissa J; Jupiter, Stacy D; Tulloch, Ayesha I T; Roelfsema, Chris; Possingham, Hugh P

    2017-03-01

    Conservation planners must reconcile trade-offs associated with using biodiversity data of differing qualities to make decisions. Coarse habitat classifications are commonly used as surrogates to design marine reserve networks when fine-scale biodiversity data are incomplete or unavailable. Although finely-classified habitat maps provide more detail, they may have more misclassification errors, a common problem when remotely-sensed imagery is used. Despite these issues, planners rarely consider the effects of errors when choosing data for spatially explicit conservation prioritizations. Here we evaluate trade-offs between accuracy and resolution of hierarchical coral reef habitat data (geomorphology and benthic substrate) derived from remote sensing, in spatial planning for Kubulau District, Fiji. For both, we use accuracy information describing the probability that a mapped habitat classification is correct to design marine reserve networks that achieve habitat conservation targets, and demonstrate inadequacies of using habitat maps without accuracy data. We show that using more detailed habitat information ensures better representation of biogenic habitats (i.e. coral and seagrass), but leads to larger and more costly reserves, because these data have more misclassification errors, and are also more expensive to obtain. Reduced impacts on fishers are possible using coarsely-classified data, which are also more cost-effective for planning reserves if we account for data collection costs, but using these data may under-represent reef habitats that are important for fisheries and biodiversity, due to the maps low thematic resolution. Finally, we show that explicitly accounting for accuracy information in decisions maximizes the chance of successful conservation outcomes by reducing the risk of missing conservation representation targets, particularly when using finely classified data.

  9. Energetic differences between bacterioplankton trophic groups and coral reef resistance.

    Science.gov (United States)

    McDole Somera, Tracey; Bailey, Barbara; Barott, Katie; Grasis, Juris; Hatay, Mark; Hilton, Brett J; Hisakawa, Nao; Nosrat, Bahador; Nulton, James; Silveira, Cynthia B; Sullivan, Chris; Brainard, Russell E; Rohwer, Forest

    2016-04-27

    Coral reefs are among the most productive and diverse marine ecosystems on the Earth. They are also particularly sensitive to changing energetic requirements by different trophic levels. Microbialization specifically refers to the increase in the energetic metabolic demands of microbes relative to macrobes and is significantly correlated with increasing human influence on coral reefs. In this study, metabolic theory of ecology is used to quantify the relative contributions of two broad bacterioplankton groups, autotrophs and heterotrophs, to energy flux on 27 Pacific coral reef ecosystems experiencing human impact to varying degrees. The effective activation energy required for photosynthesis is lower than the average energy of activation for the biochemical reactions of the Krebs cycle, and changes in the proportional abundance of these two groups can greatly affect rates of energy and materials cycling. We show that reef-water communities with a higher proportional abundance of microbial autotrophs expend more metabolic energy per gram of microbial biomass. Increased energy and materials flux through fast energy channels (i.e. water-column associated microbial autotrophs) may dampen the detrimental effects of increased heterotrophic loads (e.g. coral disease) on coral reef systems experiencing anthropogenic disturbance.

  10. Diversity and stability of herbivorous fishes on coral reefs.

    Science.gov (United States)

    Thibaut, Loic M; Connolly, Sean R; Sweatman, Hugh P A

    2012-04-01

    Biodiversity may provide insurance against ecosystem collapse by stabilizing assemblages that perform particular ecological functions (the "portfolio effect"). However, the extent to which this occurs in nature and the importance of different mechanisms that generate portfolio effects remain controversial. On coral reefs, herbivory helps maintain coral dominated states, so volatility in levels of herbivory has important implications for reef ecosystems. Here, we used an extensive time series of abundances on 35 reefs of the Great Barrier Reef of Australia to quantify the strength of the portfolio effect for herbivorous fishes. Then, we disentangled the contributions of two mechanisms that underlie it (compensatory interactions and differential responses to environmental fluctuations ["response diversity"]) by fitting a community-dynamic model that explicitly includes terms for both mechanisms. We found that portfolio effects operate strongly in herbivorous fishes, as shown by nearly independent fluctuations in abundances over time. Moreover, we found strong evidence for high response diversity, with nearly independent responses to environmental fluctuations. In contrast, we found little evidence that the portfolio effect in this system was enhanced by compensatory ecological interactions. Our results show that portfolio effects are driven principally by response diversity for herbivorous fishes on coral reefs. We conclude that portfolio effects can be very strong in nature and that, for coral reefs in particular, response diversity may help maintain herbivory above the threshold levels that trigger regime shifts.

  11. Photography of Coral Reefs from ISS

    Science.gov (United States)

    Robinson, Julie A.

    2009-01-01

    This viewgraph presentation reviews the uses of photography from the International Space Station (ISS) in studying Earth's coral reefs. The photographs include reefs in various oceans . The photographs have uses for science in assisting NASA mapping initiatives, distribution worldwide through ReefBase, and by biologist in the field.

  12. Hydrodynamic Regimes Affect Coral Reef Resilience to Ocean Acidification

    Science.gov (United States)

    Teneva, L. T.; Dunbar, R. B.; Koseff, J. R.; Fleischfresser, J. D.; Koweek, D.

    2013-05-01

    Caribbean reefs hold tremendous value as sources of food, income, coastal protection, in addition to their cultural significance. Recently, studies showed that Caribbean reef growth has been surpassed in places by excessive rates of erosion due to climate change. The rates of coral reef response to ocean pH changes and warming and the implications for ecosystem resilience remain largely unknown. One way to investigate the potential structural resilience of reefs to climate change is to measure the physical oceanographic conditions in the area. Determining the hydrodynamic regimes and residence time of water in a particular reef environment is crucial to understanding the rates of future warming and acidification a reef site would experience. Our work on Pacific Islands' hydrodynamics - Central Equatorial Pacific, Great Barrier Reef, and Western Pacific -- would be of interest to Caribbean physical oceanographers and coral reef scientists. We use a combination of Acoustic Doppler Current Profilers, Acoustic Doppler Velocimeters, temperature and salinity sensors, and pressure sensors to characterize reef hydrodynamic regimes. Our work indicates that shallower, more protected reef habitats are characterized by longer residence times, their biological signals are strongly tidally modulated, essentially subjecting such habitats to higher rates of warming and acidification in the future. Reef crest environments and fore reef habitats, on the other hand, are well-mixed with open-ocean water. The hydrodynamic regimes there condition such reef sites to more attenuated temperature and pH ranges, conditions more typical of the open ocean. Our work suggests that investigating the geomorphology and resulting localized hydrodynamics in a reef area can provide insights into the relative rates at which a reef could resist or succumb to impacts of ocean acidification. Such information for different reef islands, in the Pacific or Caribbean basins, could provide helpful insights

  13. Coral larvae move toward reef sounds.

    Science.gov (United States)

    Vermeij, Mark J A; Marhaver, Kristen L; Huijbers, Chantal M; Nagelkerken, Ivan; Simpson, Stephen D

    2010-05-14

    Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (coral larvae respond to acoustic cues that may facilitate detection of habitat from large distances and from upcurrent of preferred settlement locations. Using in situ choice chambers, we found that settling coral larvae were attracted to reef sounds, produced mainly by fish and crustaceans, which we broadcast underwater using loudspeakers. Our discovery that coral larvae can detect and respond to sound is the first description of an auditory response in the invertebrate phylum Cnidaria, which includes jellyfish, anemones, and hydroids as well as corals. If, like settlement-stage reef fish and crustaceans, coral larvae use reef noise as a cue for orientation, the alleviation of noise pollution in the marine environment may gain further urgency.

  14. Spatial competition dynamics between reef corals under ocean acidification

    Science.gov (United States)

    Horwitz, Rael; Hoogenboom, Mia O.; Fine, Maoz

    2017-01-01

    Climate change, including ocean acidification (OA), represents a major threat to coral-reef ecosystems. Although previous experiments have shown that OA can negatively affect the fitness of reef corals, these have not included the long-term effects of competition for space on coral growth rates. Our multispecies year-long study subjected reef-building corals from the Gulf of Aqaba (Red Sea) to competitive interactions under present-day ocean pH (pH 8.1) and predicted end-of-century ocean pH (pH 7.6). Results showed coral growth is significantly impeded by OA under intraspecific competition for five out of six study species. Reduced growth from OA, however, is negligible when growth is already suppressed in the presence of interspecific competition. Using a spatial competition model, our analysis indicates shifts in the competitive hierarchy and a decrease in overall coral cover under lowered pH. Collectively, our case study demonstrates how modified competitive performance under increasing OA will in all likelihood change the composition, structure and functionality of reef coral communities. PMID:28067281

  15. Spatial competition dynamics between reef corals under ocean acidification

    Science.gov (United States)

    Horwitz, Rael; Hoogenboom, Mia O.; Fine, Maoz

    2017-01-01

    Climate change, including ocean acidification (OA), represents a major threat to coral-reef ecosystems. Although previous experiments have shown that OA can negatively affect the fitness of reef corals, these have not included the long-term effects of competition for space on coral growth rates. Our multispecies year-long study subjected reef-building corals from the Gulf of Aqaba (Red Sea) to competitive interactions under present-day ocean pH (pH 8.1) and predicted end-of-century ocean pH (pH 7.6). Results showed coral growth is significantly impeded by OA under intraspecific competition for five out of six study species. Reduced growth from OA, however, is negligible when growth is already suppressed in the presence of interspecific competition. Using a spatial competition model, our analysis indicates shifts in the competitive hierarchy and a decrease in overall coral cover under lowered pH. Collectively, our case study demonstrates how modified competitive performance under increasing OA will in all likelihood change the composition, structure and functionality of reef coral communities.

  16. National Coral Reef Monitoring Program: Assessment of coral reef benthic communities in Puerto Rico from 2014-05-19 to 2014-12-03 (NCEI Accession 0151729)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic data collection for the National Coral Reef Ecosystem Monitoring Program (NCRMP) consists of two survey types: the Line Point-Intercept (LPI) method and the...

  17. Developing a Biological Condition Gradient for the Protection of Puerto Rico's Coral Reefs

    Science.gov (United States)

    We introduce the application of the Biological Condition Gradient (BCG) to coral reefs: a conceptual model that describes how biological attributes of coral reef ecosystems might change along a gradient of increasing anthropogenic stress. Under authority of the Clean Water Act, t...

  18. Developing a Biological Condition Gradient for the Protection of Puerto Rico's Coral Reefs

    Science.gov (United States)

    We introduce the application of the Biological Condition Gradient (BCG) to coral reefs: a conceptual model that describes how biological attributes of coral reef ecosystems might change along a gradient of increasing anthropogenic stress. Under authority of the Clean Water Act, t...

  19. A review of Computational Intelligence techniques in coral reef-related applications

    NARCIS (Netherlands)

    Salcedo-Sanz, S.; Cuadra, L.; Vermeij, M.J.A.

    2016-01-01

    Studies on coral reefs increasingly combine aspects of science and technology to understand the complex dynamics and processes that shape these benthic ecosystems. Recently, the use of advanced computational algorithms has entered coral reef science as new powerful tools that help solve complex cora

  20. A review of Computational Intelligence techniques in coral reef-related applications

    NARCIS (Netherlands)

    Salcedo-Sanz, S.; Cuadra, L.; Vermeij, M.J.A.

    Studies on coral reefs increasingly combine aspects of science and technology to understand the complex dynamics and processes that shape these benthic ecosystems. Recently, the use of advanced computational algorithms has entered coral reef science as new powerful tools that help solve complex

  1. Lower Mesophotic Coral Communities (60-125 m Depth) of the Northern Great Barrier Reef and Coral Sea.

    Science.gov (United States)

    Englebert, Norbert; Bongaerts, Pim; Muir, Paul R; Hay, Kyra B; Pichon, Michel; Hoegh-Guldberg, Ove

    2017-01-01

    Mesophotic coral ecosystems in the Indo-Pacific remain relatively unexplored, particularly at lower mesophotic depths (≥60 m), despite their potentially large spatial extent. Here, we used a remotely operated vehicle to conduct a qualitative assessment of the zooxanthellate coral community at lower mesophotic depths (60-125 m) at 10 different locations in the Great Barrier Reef Marine Park and the Coral Sea Commonwealth Marine Reserve. Lower mesophotic coral communities were present at all 10 locations, with zooxanthellate scleractinian corals extending down to ~100 metres on walls and ~125 m on steep slopes. Lower mesophotic coral communities were most diverse in the 60-80 m zone, while at depths of ≥100 m the coral community consisted almost exclusively of the genus Leptoseris. Collections of coral specimens (n = 213) between 60 and 125 m depth confirmed the presence of at least 29 different species belonging to 18 genera, including several potential new species and geographic/depth range extensions. Overall, this study highlights that lower mesophotic coral ecosystems are likely to be ubiquitous features on the outer reefs of the Great Barrier Reef and atolls of the Coral Sea, and harbour a generic and species richness of corals that is much higher than thus far reported. Further research efforts are urgently required to better understand and manage these ecosystems as part of the Great Barrier Reef Marine Park and Coral Sea Commonwealth Marine Reserve.

  2. Lower Mesophotic Coral Communities (60-125 m Depth) of the Northern Great Barrier Reef and Coral Sea

    Science.gov (United States)

    Englebert, Norbert; Bongaerts, Pim; Muir, Paul R.; Hay, Kyra B.; Pichon, Michel; Hoegh-Guldberg, Ove

    2017-01-01

    Mesophotic coral ecosystems in the Indo-Pacific remain relatively unexplored, particularly at lower mesophotic depths (≥60 m), despite their potentially large spatial extent. Here, we used a remotely operated vehicle to conduct a qualitative assessment of the zooxanthellate coral community at lower mesophotic depths (60–125 m) at 10 different locations in the Great Barrier Reef Marine Park and the Coral Sea Commonwealth Marine Reserve. Lower mesophotic coral communities were present at all 10 locations, with zooxanthellate scleractinian corals extending down to ~100 metres on walls and ~125 m on steep slopes. Lower mesophotic coral communities were most diverse in the 60–80 m zone, while at depths of ≥100 m the coral community consisted almost exclusively of the genus Leptoseris. Collections of coral specimens (n = 213) between 60 and 125 m depth confirmed the presence of at least 29 different species belonging to 18 genera, including several potential new species and geographic/depth range extensions. Overall, this study highlights that lower mesophotic coral ecosystems are likely to be ubiquitous features on the outer reefs of the Great Barrier Reef and atolls of the Coral Sea, and harbour a generic and species richness of corals that is much higher than thus far reported. Further research efforts are urgently required to better understand and manage these ecosystems as part of the Great Barrier Reef Marine Park and Coral Sea Commonwealth Marine Reserve. PMID:28146574

  3. Behaviourally mediated phenotypic selection in a disturbed coral reef environment.

    Directory of Open Access Journals (Sweden)

    Mark I McCormick

    Full Text Available Natural and anthropogenic disturbances are leading to changes in the nature of many habitats globally, and the magnitude and frequency of these perturbations are predicted to increase under climate change. Globally coral reefs are one of the most vulnerable ecosystems to climate change. Fishes often show relatively rapid declines in abundance when corals become stressed and die, but the processes responsible are largely unknown. This study explored the mechanism by which coral bleaching may influence the levels and selective nature of mortality on a juvenile damselfish, Pomacentrus amboinensis, which associates with hard coral. Recently settled fish had a low propensity to migrate small distances (40 cm between habitat patches, even when densities were elevated to their natural maximum. Intraspecific interactions and space use differ among three habitats: live hard coral, bleached coral and dead algal-covered coral. Large fish pushed smaller fish further from the shelter of bleached and dead coral thereby exposing smaller fish to higher mortality than experienced on healthy coral. Small recruits suffered higher mortality than large recruits on bleached and dead coral. Mortality was not size selective on live coral. Survival was 3 times as high on live coral as on either bleached or dead coral. Subtle behavioural interactions between fish and their habitats influence the fundamental link between life history stages, the distribution of phenotypic traits in the local population and potentially the evolution of life history strategies.

  4. Fish-derived nutrient hotspots shape coral reef benthic communities.

    Science.gov (United States)

    Shantz, Andrew A; Ladd, Mark C; Schrack, Elizabeth; Burkepile, Deron E

    2015-12-01

    Animal-derived nutrients play an important role in structuring nutrient regimes within and between ecosystems. When animals undergo repetitive, aggregating behavior through time, they can create nutrient hotspots where rates of biogeochemical activity are higher than those found in the surrounding environment. In turn, these hotspots can influence ecosystem processes and community structure. We examined the potential for reef fishes from the family Haemulidae (grunts) to create nutrient hotspots and the potential impact of these hotspots on reef communities. To do so, we tracked the schooling locations of diurnally migrating grunts, which shelter at reef sites during the day but forage off reef each night, and measured the impact of these fish schools on benthic communities. We found that grunt schools showed a high degree of site fidelity, repeatedly returning to the same coral heads. These aggregations created nutrient hotspots around coral heads where nitrogen and phosphorus delivery was roughly 10 and 7 times the respective rates of delivery to structurally similar sites that lacked schools of these fishes. In turn, grazing rates of herbivorous fishes at grunt-derived hotspots were approximately 3 times those of sites where grunts were rare. These differences in nutrient delivery and grazing led to distinct benthic communities with higher cover of crustose coralline algae and less total algal abundance at grunt aggregation sites. Importantly, coral growth was roughly 1.5 times greater at grunt hotspots, likely due to the important nutrient subsidy. Our results suggest that schooling reef fish and their nutrient subsidies play an important role in mediating community structure on coral reefs and that overfishing may have important negative consequences on ecosystem functions. As such, management strategies must consider mesopredatory fishes in addition to current protection often offered to herbivores and top-tier predators. Furthermore, our results suggest that

  5. Biological Criteria for Protection of U.S. Coral Reefs.

    Science.gov (United States)

    Coral reef ecosystems are threatened by natural stressors, human activities, and natural stressors exacerbated by human activities. Under the U.S. Clean Water Act, States and Territories may guard against anthropogenic threats by adopting water quality standards based on biologic...

  6. Biological Criteria for Protection of U.S. Coral Reefs.

    Science.gov (United States)

    Coral reef ecosystems are threatened by natural stressors, human activities, and natural stressors exacerbated by human activities. Under the U.S. Clean Water Act, States and Territories may guard against anthropogenic threats by adopting water quality standards based on biologic...

  7. Physics of coral reef systems in a shallow tidal embayment

    NARCIS (Netherlands)

    Hoitink, Antonius Johannes Franciscus

    2003-01-01

    Ongoing deforestation in the tropics involves higher river discharges and an increase of runoff, which has consequences to coastal ecosystems. The dispersal of fluvial sediment and freshwater by marine processes affects the environmental determinants of coral reefs near the coast, which include temp

  8. Reversal of ocean acidification enhances net coral reef calcification.

    Science.gov (United States)

    Albright, Rebecca; Caldeira, Lilian; Hosfelt, Jessica; Kwiatkowski, Lester; Maclaren, Jana K; Mason, Benjamin M; Nebuchina, Yana; Ninokawa, Aaron; Pongratz, Julia; Ricke, Katharine L; Rivlin, Tanya; Schneider, Kenneth; Sesboüé, Marine; Shamberger, Kathryn; Silverman, Jacob; Wolfe, Kennedy; Zhu, Kai; Caldeira, Ken

    2016-03-17

    Approximately one-quarter of the anthropogenic carbon dioxide released into the atmosphere each year is absorbed by the global oceans, causing measurable declines in surface ocean pH, carbonate ion concentration ([CO3(2-)]), and saturation state of carbonate minerals (Ω). This process, referred to as ocean acidification, represents a major threat to marine ecosystems, in particular marine calcifiers such as oysters, crabs, and corals. Laboratory and field studies have shown that calcification rates of many organisms decrease with declining pH, [CO3(2-)], and Ω. Coral reefs are widely regarded as one of the most vulnerable marine ecosystems to ocean acidification, in part because the very architecture of the ecosystem is reliant on carbonate-secreting organisms. Acidification-induced reductions in calcification are projected to shift coral reefs from a state of net accretion to one of net dissolution this century. While retrospective studies show large-scale declines in coral, and community, calcification over recent decades, determining the contribution of ocean acidification to these changes is difficult, if not impossible, owing to the confounding effects of other environmental factors such as temperature. Here we quantify the net calcification response of a coral reef flat to alkalinity enrichment, and show that, when ocean chemistry is restored closer to pre-industrial conditions, net community calcification increases. In providing results from the first seawater chemistry manipulation experiment of a natural coral reef community, we provide evidence that net community calcification is depressed compared with values expected for pre-industrial conditions, indicating that ocean acidification may already be impairing coral reef growth.

  9. Reversal of ocean acidification enhances net coral reef calcification

    Science.gov (United States)

    Albright, Rebecca; Caldeira, Lilian; Hosfelt, Jessica; Kwiatkowski, Lester; MacLaren, Jana K.; Mason, Benjamin M.; Nebuchina, Yana; Ninokawa, Aaron; Pongratz, Julia; Ricke, Katharine L.; Rivlin, Tanya; Schneider, Kenneth; Sesboüé, Marine; Shamberger, Kathryn; Silverman, Jacob; Wolfe, Kennedy; Zhu, Kai; Caldeira, Ken

    2016-03-01

    Approximately one-quarter of the anthropogenic carbon dioxide released into the atmosphere each year is absorbed by the global oceans, causing measurable declines in surface ocean pH, carbonate ion concentration ([CO32-]), and saturation state of carbonate minerals (Ω). This process, referred to as ocean acidification, represents a major threat to marine ecosystems, in particular marine calcifiers such as oysters, crabs, and corals. Laboratory and field studies have shown that calcification rates of many organisms decrease with declining pH, [CO32-], and Ω. Coral reefs are widely regarded as one of the most vulnerable marine ecosystems to ocean acidification, in part because the very architecture of the ecosystem is reliant on carbonate-secreting organisms. Acidification-induced reductions in calcification are projected to shift coral reefs from a state of net accretion to one of net dissolution this century. While retrospective studies show large-scale declines in coral, and community, calcification over recent decades, determining the contribution of ocean acidification to these changes is difficult, if not impossible, owing to the confounding effects of other environmental factors such as temperature. Here we quantify the net calcification response of a coral reef flat to alkalinity enrichment, and show that, when ocean chemistry is restored closer to pre-industrial conditions, net community calcification increases. In providing results from the first seawater chemistry manipulation experiment of a natural coral reef community, we provide evidence that net community calcification is depressed compared with values expected for pre-industrial conditions, indicating that ocean acidification may already be impairing coral reef growth.

  10. Brazilian coral reefs in a period of global change: A synthesis

    Directory of Open Access Journals (Sweden)

    Zelinda M. A. N. Leão

    Full Text Available Abstract Brazilian coral reefs form structures significantly different from the well-known reef models, as follows: (i they have a growth form of mushroom-shaped coral pinnacles called "chapeirões", (ii they are built by a low diversity coral fauna rich in endemic species, most of them relic forms dating back to the Tertiary, and (iii the nearshore bank reefs are surrounded by siliciclastic sediments. The reefs are distributed in the following four major sectors along the Brazilian coast: the northern, the northeastern and the eastern regions, and the oceanic islands, but certain isolated coral species can be found in warmer waters in embayments of the southern region. There are different types of bank reefs, fringing reefs, isolated "chapeirões" and an atoll present along the Brazilian coast. Corals, milleporids and coralline algae build the rigid frame of the reefs. The areas in which the major coral reefs occur correspond to regions in which nearby urban centers are experiencing accelerated growth, and tourism development is rapidly increasing. The major human effects on the reef ecosystem are mostly associated with the increased sedimentation due to the removal of the Atlantic rainforest and the discharge of industrial and urban effluents. The effects of the warming of oceanic waters that had previously affected several reef areas with high intensity coral bleaching had not shown, by the time of the 2010 event, any episodes of mass coral mortality on Brazilian reefs.

  11. Marine reserves enhance the recovery of corals on Caribbean reefs.

    Directory of Open Access Journals (Sweden)

    Peter J Mumby

    Full Text Available The fisheries and biodiversity benefits of marine reserves are widely recognised but there is mounting interest in exploiting the importance of herbivorous fishes as a tool to help ecosystems recover from climate change impacts. This approach might be particularly suitable for coral reefs, which are acutely threatened by climate change, yet the trophic cascades generated by reserves are strong enough that they might theoretically enhance the rate of coral recovery after disturbance. However, evidence for reserves facilitating coral recovery has been lacking. Here we investigate whether reductions in macroalgal cover, caused by recovery of herbivorous parrotfishes within a reserve, have resulted in a faster rate of coral recovery than in areas subject to fishing. Surveys of ten sites inside and outside a Bahamian marine reserve over a 2.5-year period demonstrated that increases in coral cover, including adjustments for the initial size-distribution of corals, were significantly higher at reserve sites than those in non-reserve sites. Furthermore, macroalgal cover was significantly negatively correlated with the change in total coral cover over time. Recovery rates of individual species were generally consistent with small-scale manipulations on coral-macroalgal interactions, but also revealed differences that demonstrate the difficulties of translating experiments across spatial scales. Size-frequency data indicated that species which were particularly affected by high abundances of macroalgae outside the reserve had a population bottleneck restricting the supply of smaller corals to larger size classes. Importantly, because coral cover increased from a heavily degraded state, and recovery from such states has not previously been described, similar or better outcomes should be expected for many reefs in the region. Reducing herbivore exploitation as part of an ecosystem-based management strategy for coral reefs appears to be justified.

  12. Marine reserves enhance the recovery of corals on Caribbean reefs.

    Science.gov (United States)

    Mumby, Peter J; Harborne, Alastair R

    2010-01-11

    The fisheries and biodiversity benefits of marine reserves are widely recognised but there is mounting interest in exploiting the importance of herbivorous fishes as a tool to help ecosystems recover from climate change impacts. This approach might be particularly suitable for coral reefs, which are acutely threatened by climate change, yet the trophic cascades generated by reserves are strong enough that they might theoretically enhance the rate of coral recovery after disturbance. However, evidence for reserves facilitating coral recovery has been lacking. Here we investigate whether reductions in macroalgal cover, caused by recovery of herbivorous parrotfishes within a reserve, have resulted in a faster rate of coral recovery than in areas subject to fishing. Surveys of ten sites inside and outside a Bahamian marine reserve over a 2.5-year period demonstrated that increases in coral cover, including adjustments for the initial size-distribution of corals, were significantly higher at reserve sites than those in non-reserve sites. Furthermore, macroalgal cover was significantly negatively correlated with the change in total coral cover over time. Recovery rates of individual species were generally consistent with small-scale manipulations on coral-macroalgal interactions, but also revealed differences that demonstrate the difficulties of translating experiments across spatial scales. Size-frequency data indicated that species which were particularly affected by high abundances of macroalgae outside the reserve had a population bottleneck restricting the supply of smaller corals to larger size classes. Importantly, because coral cover increased from a heavily degraded state, and recovery from such states has not previously been described, similar or better outcomes should be expected for many reefs in the region. Reducing herbivore exploitation as part of an ecosystem-based management strategy for coral reefs appears to be justified.

  13. Human Dimensions of Coral Reef Social-Ecological Systems

    Directory of Open Access Journals (Sweden)

    John N. Kittinger

    2012-12-01

    Full Text Available Coral reefs are among the most diverse ecosystems on the planet but are declining because of human activities. Despite general recognition of the human role in the plight of coral reefs, the vast majority of research focuses on the ecological rather than the human dimensions of reef ecosystems, limiting our understanding of social relationships with these environments as well as potential solutions for reef recovery. General frameworks for social-ecological systems (SESs have been advanced, but system-specific approaches are needed to develop a more nuanced view of human-environmental interactions for specific contexts and resource systems, and at specific scales. We synthesize existing concepts related to SESs and present a human dimensions framework that explores the linkages between social system structural traits, human activities, ecosystem services, and human well-being in coral reef SESs. Key features of the framework include social-ecological reciprocity, proximate and underlying dimensions, and the directionality of key relationships and feedback loops. Such frameworks are needed if human dimensions research is to be more fully integrated into studies of ecosystem change and the sustainability of linked SESs.

  14. Challenges for Managing Fisheries on Diverse Coral Reefs

    Directory of Open Access Journals (Sweden)

    Douglas Fenner

    2012-03-01

    Full Text Available Widespread coral reef decline has included the decline of reef fish populations, and the subsistence and artisanal fisheries that depend on them. Overfishing and destructive fishing have been identified as the greatest local threats to coral reefs, but the greatest future threats are acidification and increases in mass coral bleaching caused by global warming. Some reefs have shifted from dominance by corals to macroalgae, in what are called “phase shifts”. Depletion of herbivores including fishes has been identified as a contributor to such phase shifts, though nutrients are also involved in complex interactions with herbivory and competition. The depletion of herbivorous fishes implies a reduction of the resilience of coral reefs to the looming threat of mass coral mortality from bleaching, since mass coral deaths are likely to be followed by mass macroalgal blooms on the newly exposed dead substrates. Conventional stock assessment of each fish species would be the preferred option for understanding the status of the reef fishes, but this is far too expensive to be practical because of the high diversity of the fishery and poverty where most reefs are located. In addition, stock assessment models and fisheries in general assume density dependent populations, but a key prediction that stocks recover from fishing is not always confirmed. Catch Per Unit Effort (CPUE has far too many weaknesses to be a useful method. The ratio of catch to stock and the proportion of catch that is mature depend on fish catch data, and are heavily biased toward stocks that are in good condition and incapable of finding species that are in the worst condition. Near-pristine reefs give us a reality check about just how much we have lost. Common fisheries management tools that control effort or catch are often prohibitively difficult to enforce for most coral reefs except in developed countries. Ecosystem-based management requires management of impacts of fishing

  15. A geological perspective on the degradation and conservation of western Atlantic coral reefs.

    Science.gov (United States)

    Kuffner, Ilsa B; Toth, Lauren T

    2016-08-01

    Continuing coral-reef degradation in the western Atlantic is resulting in loss of ecological and geologic functions of reefs. With the goal of assisting resource managers and stewards of reefs in setting and measuring progress toward realistic goals for coral-reef conservation and restoration, we examined reef degradation in this region from a geological perspective. The importance of ecosystem services provided by coral reefs-as breakwaters that dissipate wave energy and protect shorelines and as providers of habitat for innumerable species-cannot be overstated. However, the few coral species responsible for reef building in the western Atlantic during the last approximately 1.5 million years are not thriving in the 21st century. These species are highly sensitive to abrupt temperature extremes, prone to disease infection, and have low sexual reproductive potential. Their vulnerability and the low functional redundancy of branching corals have led to the low resilience of western Atlantic reef ecosystems. The decrease in live coral cover over the last 50 years highlights the need for study of relict (senescent) reefs, which, from the perspective of coastline protection and habitat structure, may be just as important to conserve as the living coral veneer. Research is needed to characterize the geological processes of bioerosion, reef cementation, and sediment transport as they relate to modern-day changes in reef elevation. For example, although parrotfish remove nuisance macroalgae, possibly promoting coral recruitment, they will not save Atlantic reefs from geological degradation. In fact, these fish are quickly nibbling away significant quantities of Holocene reef framework. The question of how different biota covering dead reefs affect framework resistance to biological and physical erosion needs to be addressed. Monitoring and managing reefs with respect to physical resilience, in addition to ecological resilience, could optimize the expenditure of resources

  16. Digital reef rugosity estimates coral reef habitat complexity.

    Science.gov (United States)

    Dustan, Phillip; Doherty, Orla; Pardede, Shinta

    2013-01-01

    Ecological habitats with greater structural complexity contain more species due to increased niche diversity. This is especially apparent on coral reefs where individual coral colonies aggregate to give a reef its morphology, species zonation, and three dimensionality. Structural complexity is classically measured with a reef rugosity index, which is the ratio of a straight line transect to the distance a flexible chain of equal length travels when draped over the reef substrate; yet, other techniques from visual categories to remote sensing have been used to characterize structural complexity at scales from microhabitats to reefscapes. Reef-scale methods either lack quantitative precision or are too time consuming to be routinely practical, while remotely sensed indices are mismatched to the finer scale morphology of coral colonies and reef habitats. In this communication a new digital technique, Digital Reef Rugosity (DRR) is described which utilizes a self-contained water level gauge enabling a diver to quickly and accurately characterize rugosity with non-invasive millimeter scale measurements of coral reef surface height at decimeter intervals along meter scale transects. The precise measurements require very little post-processing and are easily imported into a spreadsheet for statistical analyses and modeling. To assess its applicability we investigated the relationship between DRR and fish community structure at four coral reef sites on Menjangan Island off the northwest corner of Bali, Indonesia and one on mainland Bali to the west of Menjangan Island; our findings show a positive relationship between DRR and fish diversity. Since structural complexity drives key ecological processes on coral reefs, we consider that DRR may become a useful quantitative community-level descriptor to characterize reef complexity.

  17. NOAA's Coral Reef Conservation Program: 2016 projects to address coral reef conservation issues

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 2016 the following projects will take place to address aspects of coral reef conservation: Enhancing Management of Pacific ESA-listed Corals with Improved Utility...

  18. The preparation of the rice coral Montipora capitata nubbins for application in coral-reef ecotoxicology.

    Science.gov (United States)

    Vijayavel, K; Richmond, R H

    2012-04-01

    Securing adequate and appropriate source material for coral-reef ecotoxicology studies is a significant impediment to conducting various experiments supporting the goal of conserving coral-reef ecosystems. Collecting colonies from wild stocks may be counter to protecting coral reef populations. To address this issue the rice coral Montipora capitata was used to generate sufficient genetically identical nubbins for research purposes. Growth and survival rates of these laboratory-prepared M. capitata nubbins were studied over a period of 90 days. The resulting data support the conclusion that the laboratory-prepared M. capitata nubbins showed successful growth and survival rates and are the best solution to solve the source material issue for lab experimentation. This paper describes the laboratory method used for the preparation and maintenance of these M. capitata nubbins and discusses the benefits and difficulties of using these nubbins in ecotoxicity studies.

  19. Coral Reefs and People in a High-CO2 World: Where Can Science Make a Difference to People?

    National Research Council Canada - National Science Library

    Pendleton, Linwood; Comte, Adrien; Langdon, Chris; Ekstrom, Julia A; Cooley, Sarah R; Suatoni, Lisa; Beck, Michael W; Brander, Luke M; Burke, Lauretta; Cinner, Josh E; Doherty, Carolyn; Edwards, Peter E. T; Gledhill, Dwight; Jiang, Li-Qing; van Hooidonk, Ruben J; Teh, Louise; Waldbusser, George G; Ritter, Jessica

    2016-01-01

      Reefs and People at Risk Increasing levels of carbon dioxide in the atmosphere put shallow, warm-water coral reef ecosystems, and the people who depend upon them at risk from two key global environmental stresses: 1...

  20. How will coral reef fish communities respond to climate-driven disturbances? Insight from landscape-scale perturbations.

    Science.gov (United States)

    Adam, Thomas C; Brooks, Andrew J; Holbrook, Sally J; Schmitt, Russell J; Washburn, Libe; Bernardi, Giacomo

    2014-09-01

    Global climate change is rapidly altering disturbance regimes in many ecosystems including coral reefs, yet the long-term impacts of these changes on ecosystem structure and function are difficult to predict. A major ecosystem service provided by coral reefs is the provisioning of physical habitat for other organisms, and consequently, many of the effects of climate change on coral reefs will be mediated by their impacts on habitat structure. Therefore, there is an urgent need to understand the independent and combined effects of coral mortality and loss of physical habitat on reef-associated biota. Here, we use a unique series of events affecting the coral reefs around the Pacific island of Moorea, French Polynesia to differentiate between the impacts of coral mortality and the degradation of physical habitat on the structure of reef fish communities. We found that, by removing large amounts of physical habitat, a tropical cyclone had larger impacts on reef fish communities than an outbreak of coral-eating sea stars that caused widespread coral mortality but left the physical structure intact. In addition, the impacts of declining structural complexity on reef fish assemblages accelerated as structure became increasingly rare. Structure provided by dead coral colonies can take up to decades to erode following coral mortality, and, consequently, our results suggest that predictions based on short-term studies are likely to grossly underestimate the long-term impacts of coral decline on reef fish communities.

  1. Marine protected areas increase resilience among coral reef communities.

    Science.gov (United States)

    Mellin, Camille; Aaron MacNeil, M; Cheal, Alistair J; Emslie, Michael J; Julian Caley, M

    2016-06-01

    With marine biodiversity declining globally at accelerating rates, maximising the effectiveness of conservation has become a key goal for local, national and international regulators. Marine protected areas (MPAs) have been widely advocated for conserving and managing marine biodiversity yet, despite extensive research, their benefits for conserving non-target species and wider ecosystem functions remain unclear. Here, we demonstrate that MPAs can increase the resilience of coral reef communities to natural disturbances, including coral bleaching, coral diseases, Acanthaster planci outbreaks and storms. Using a 20-year time series from Australia's Great Barrier Reef, we show that within MPAs, (1) reef community composition was 21-38% more stable; (2) the magnitude of disturbance impacts was 30% lower and (3) subsequent recovery was 20% faster that in adjacent unprotected habitats. Our results demonstrate that MPAs can increase the resilience of marine communities to natural disturbance possibly through herbivory, trophic cascades and portfolio effects.

  2. The engine of the reef: Photobiology of the coral-algal symbiosis

    OpenAIRE

    Melissa Susan Roth

    2014-01-01

    Coral reef ecosystems thrive in tropical oligotrophic oceans because of the relationship between corals and endosymbiotic dinoflagellate algae called Symbiodinium. Symbiodinium convert sunlight and carbon dioxide into organic carbon and oxygen to fuel coral growth and calcification, creating habitat for these diverse and productive ecosystems. Light is thus a key regulating factor shaping the productivity, physiology, and ecology of the coral holobiont. Similar to all oxygenic photoautotrophs...

  3. Monitoring of coral reef ecosystems on the Island of Hawaii from 22 May 1999 to 25 May 1999 through the Quantitative Underwater Ecological Surveying Techniques (QUEST) project (NODC Accession 0000264)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In an effort to detect spatial and temporal changes in the structure of the coral reef community, coral coverage and reef fish density and diversity were documented...

  4. Determining the extent and characterizing coral reef habitats of the northern latitudes of the Florida Reef Tract (Martin County).

    Science.gov (United States)

    Walker, Brian K; Gilliam, David S

    2013-01-01

    Climate change has recently been implicated in poleward shifts of many tropical species including corals; thus attention focused on higher-latitude coral communities is warranted to investigate possible range expansions and ecosystem shifts due to global warming. As the northern extension of the Florida Reef Tract (FRT), the third-largest barrier reef ecosystem in the world, southeast Florida (25-27° N latitude) is a prime region to study such effects. Most of the shallow-water FRT benthic habitats have been mapped, however minimal data and limited knowledge exist about the coral reef communities of its northernmost reaches off Martin County. First benthic habitat mapping was conducted using newly acquired high resolution LIDAR bathymetry and aerial photography where possible to map the spatial extent of coral reef habitats. Quantitative data were collected to characterize benthic cover and stony coral demographics and a comprehensive accuracy assessment was performed. The data were then analyzed in a habitat biogeography context to determine if a new coral reef ecosystem region designation was warranted. Of the 374 km(2) seafloor mapped, 95.2% was Sand, 4.1% was Coral Reef and Colonized Pavement, and 0.7% was Other Delineations. Map accuracy assessment yielded an overall accuracy of 94.9% once adjusted for known map marginal proportions. Cluster analysis of cross-shelf habitat type and widths indicated that the benthic habitats were different than those further south and warranted designation of a new coral reef ecosystem region. Unlike the FRT further south, coral communities were dominated by cold-water tolerant species and LIDAR morphology indicated no evidence of historic reef growth during warmer climates. Present-day hydrographic conditions may be inhibiting poleward expansion of coral communities along Florida. This study provides new information on the benthic community composition of the northern FRT, serving as a baseline for future community shift and

  5. Determining the extent and characterizing coral reef habitats of the northern latitudes of the Florida Reef Tract (Martin County.

    Directory of Open Access Journals (Sweden)

    Brian K Walker

    Full Text Available Climate change has recently been implicated in poleward shifts of many tropical species including corals; thus attention focused on higher-latitude coral communities is warranted to investigate possible range expansions and ecosystem shifts due to global warming. As the northern extension of the Florida Reef Tract (FRT, the third-largest barrier reef ecosystem in the world, southeast Florida (25-27° N latitude is a prime region to study such effects. Most of the shallow-water FRT benthic habitats have been mapped, however minimal data and limited knowledge exist about the coral reef communities of its northernmost reaches off Martin County. First benthic habitat mapping was conducted using newly acquired high resolution LIDAR bathymetry and aerial photography where possible to map the spatial extent of coral reef habitats. Quantitative data were collected to characterize benthic cover and stony coral demographics and a comprehensive accuracy assessment was performed. The data were then analyzed in a habitat biogeography context to determine if a new coral reef ecosystem region designation was warranted. Of the 374 km(2 seafloor mapped, 95.2% was Sand, 4.1% was Coral Reef and Colonized Pavement, and 0.7% was Other Delineations. Map accuracy assessment yielded an overall accuracy of 94.9% once adjusted for known map marginal proportions. Cluster analysis of cross-shelf habitat type and widths indicated that the benthic habitats were different than those further south and warranted designation of a new coral reef ecosystem region. Unlike the FRT further south, coral communities were dominated by cold-water tolerant species and LIDAR morphology indicated no evidence of historic reef growth during warmer climates. Present-day hydrographic conditions may be inhibiting poleward expansion of coral communities along Florida. This study provides new information on the benthic community composition of the northern FRT, serving as a baseline for future

  6. Coral Reef Protection Implementation Plan

    Science.gov (United States)

    2007-11-02

    ecosystems. These reports Caribbean, Gulf of Mexico , and Pacific Ocean." For the will also serve as an awareness tool for agencies to purposes of this report...alternatives for proposed discharges of - 7 dredged or fill material into U.S or international waters, *o SECTION THi- zEE EXISTING FUNDING SOURCES FOR CORAL...facilities on several thousand acres within the Ko’olaupoko Region on O’ahu. Popu- NORTHERN GULF OF MEXICO lation growth and development throughout

  7. Direct evaluation of macroalgal removal by herbivorous coral reef fishes

    Science.gov (United States)

    Mantyka, C. S.; Bellwood, D. R.

    2007-06-01

    Few studies have examined the relative functional impacts of individual herbivorous fish species on coral reef ecosystem processes in the Indo-Pacific. This study assessed the potential grazing impact of individual species within an inshore herbivorous reef fish assemblage on the central Great Barrier Reef (GBR), by determining which fish species were able to remove particular macroalgal species. Transplanted multiple-choice algal assays and remote stationary underwater digital video cameras were used to quantify the impact of local herbivorous reef fish species on 12 species of macroalgae. Macroalgal removal by the fishes was rapid. Within 3 h of exposure to herbivorous reef fishes there was significant evidence of intense grazing. After 12 h of exposure, 10 of the 12 macroalgal species had decreased to less than 15% of their original mass. Chlorodesmis fastigiata (Chlorophyta) and Galaxaura sp. (Rhodophyta) showed significantly less susceptibility to herbivorous reef fish grazing than all other macroalgae, even after 24 h exposure. Six herbivorous and/or nominally herbivorous reef fish species were identified as the dominant grazers of macroalgae: Siganus doliatus, Siganus canaliculatus, Chlorurus microrhinos, Hipposcarus longiceps, Scarus rivulatus and Pomacanthus sexstriatus. The siganid S. doliatus fed heavily on Hypnea sp., while S. canaliculatus fed intensively on Sargassum sp. Variation in macroalgal susceptibility was not clearly correlated with morphological and/or chemical defenses that have been previously suggested as deterrents against herbivory. Nevertheless, the results stress the potential importance of individual herbivorous reef fish species in removing macroalgae from coral reefs.

  8. A coral-on-a-chip microfluidic platform enabling live-imaging microscopy of reef-building corals.

    Science.gov (United States)

    Shapiro, Orr H; Kramarsky-Winter, Esti; Gavish, Assaf R; Stocker, Roman; Vardi, Assaf

    2016-03-04

    Coral reefs, and the unique ecosystems they support, are facing severe threats by human activities and climate change. Our understanding of these threats is hampered by the lack of robust approaches for studying the micro-scale interactions between corals and their environment. Here we present an experimental platform, coral-on-a-chip, combining micropropagation and microfluidics to allow direct microscopic study of live coral polyps. The small and transparent coral micropropagates are ideally suited for live-imaging microscopy, while the microfluidic platform facilitates long-term visualization under controlled environmental conditions. We demonstrate the usefulness of this approach by imaging coral micropropagates at previously unattainable spatio-temporal resolutions, providing new insights into several micro-scale processes including coral calcification, coral-pathogen interaction and the loss of algal symbionts (coral bleaching). Coral-on-a-chip thus provides a powerful method for studying coral physiology in vivo at the micro-scale, opening new vistas in coral biology.

  9. A geological perspective on the degradation and conservation of western Atlantic coral reefs

    Science.gov (United States)

    Kuffner, Ilsa B.; Toth, Lauren T.

    2016-01-01

    Continuing coral-reef degradation in the western Atlantic is resulting in loss of ecological and geologic functions of reefs. With the goal of assisting resource managers and stewards of reefs in setting and measuring progress toward realistic goals for coral-reef conservation and restoration, we examined reef degradation in this region from a geological perspective. The importance of ecosystem services provided by coral reefs—as breakwaters that dissipate wave energy and protect shorelines and as providers of habitat for innumerable species—cannot be overstated. However, the few coral species responsible for reef building in the western Atlantic during the last approximately 1.5 million years are not thriving in the 21st century. These species are highly sensitive to abrupt temperature extremes, prone to disease infection, and have low sexual reproductive potential. Their vulnerability and the low functional redundancy of branching corals have led to the low resilience of western Atlantic reef ecosystems. The decrease in live coral cover over the last 50 years highlights the need for study of relict (senescent) reefs, which, from the perspective of coastline protection and habitat structure, may be just as important to conserve as the living coral veneer. Research is needed to characterize the geological processes of bioerosion, reef cementation, and sediment transport as they relate to modern-day changes in reef elevation. For example, although parrotfish remove nuisance macroalgae, possibly promoting coral recruitment, they will not save Atlantic reefs from geological degradation. In fact, these fish are quickly nibbling away significant quantities of Holocene reef framework. The question of how different biota covering dead reefs affect framework resistance to biological and physical erosion needs to be addressed. Monitoring and managing reefs with respect to physical resilience, in addition to ecological resilience, could optimize the expenditure of

  10. A coral reef refuge in the Red Sea.

    Science.gov (United States)

    Fine, Maoz; Gildor, Hezi; Genin, Amatzia

    2013-12-01

    The stability and persistence of coral reefs in the decades to come is uncertain due to global warming and repeated bleaching events that will lead to reduced resilience of these ecological and socio-economically important ecosystems. Identifying key refugia is potentially important for future conservation actions. We suggest that the Gulf of Aqaba (GoA) (Red Sea) may serve as a reef refugium due to a unique suite of environmental conditions. Our hypothesis is based on experimental detection of an exceptionally high bleaching threshold of northern Red Sea corals and on the potential dispersal of coral planulae larvae through a selective thermal barrier estimated using an ocean model. We propose that millennia of natural selection in the form of a thermal barrier at the southernmost end of the Red Sea have selected coral genotypes that are less susceptible to thermal stress in the northern Red Sea, delaying bleaching events in the GoA by at least a century.

  11. The diversity of coral reefs: what are we missing?

    Directory of Open Access Journals (Sweden)

    Laetitia Plaisance

    Full Text Available Tropical reefs shelter one quarter to one third of all marine species but one third of the coral species that construct reefs are now at risk of extinction. Because traditional methods for assessing reef diversity are extremely time consuming, taxonomic expertise for many groups is lacking, and marine organisms are thought to be less vulnerable to extinction, most discussions of reef conservation focus on maintenance of ecosystem services rather than biodiversity loss. In this study involving the three major oceans with reef growth, we provide new biodiversity estimates based on quantitative sampling and DNA barcoding. We focus on crustaceans, which are the second most diverse group of marine metazoans. We show exceptionally high numbers of crustacean species associated with coral reefs relative to sampling effort (525 species from a combined, globally distributed sample area of 6.3 m(2. The high prevalence of rare species (38% encountered only once, the low level of spatial overlap (81% found in only one locality and the biogeographic patterns of diversity detected (Indo-West Pacific>Central Pacific>Caribbean are consistent with results from traditional survey methods, making this approach a reliable and efficient method for assessing and monitoring biodiversity. The finding of such large numbers of species in a small total area suggests that coral reef diversity is seriously under-detected using traditional survey methods, and by implication, underestimated.

  12. Coral reefs under rapid climate change and ocean acidification.

    Science.gov (United States)

    Hoegh-Guldberg, O; Mumby, P J; Hooten, A J; Steneck, R S; Greenfield, P; Gomez, E; Harvell, C D; Sale, P F; Edwards, A J; Caldeira, K; Knowlton, N; Eakin, C M; Iglesias-Prieto, R; Muthiga, N; Bradbury, R H; Dubi, A; Hatziolos, M E

    2007-12-14

    Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef-associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled-up management intervention and decisive action on global emissions are required if the loss of coral-dominated ecosystems is to be avoided.

  13. Destruction of corals and other reef animals by coral spawn slicks on Ningaloo Reef, Western Australia

    Science.gov (United States)

    Simpson, C. J.; Cary, J. L.; Masini, R. J.

    1993-11-01

    In March 1989, most of the corals near Coral Bay, off the north-western coastline of Australia, spawned several nights earlier than usual. Flood, rather than ebb, tides at the time of spawning combined with light north-west winds and low swell conditions to restrict the dispersal of coral propagules and, as a result, large amounts of coral spawn were trapped in the bay, forming extensive slicks. Fish and other animals began to die almost immediately, and over the next few days, over 1 million fish, representing at least 80 species, were washed ashore. A survey of the benthic communities revealed extensive mortality of corals and other reef animals over an area of about 3 km2. Live coral cover in this area decreased from 42.9% to 9.4% and several large coral colonies up to 10 m in diameter were killed. The observed mortality was presumably the result of hypoxia (oxygen depletion) created initially by the respiratory demand of the coral spawn and maintained by the biological oxygen demand of the decomposing spawn slicks and dead animals. Anecdotal reports of corals and other reef animals dying in the vicinity of coral spawn slicks on other reefs in Western Australia suggest that this phenomenon may be a relatively common event on shallow coral reefs where coral mass spawning occurs. These records and observations document, for the first time, a new source of natural disturbance that has a significant influence on the community structure of some coral reefs.

  14. EPA Field Manual for Coral Reef Assessments

    Science.gov (United States)

    The Water Quality Research Program (WQRP) supports development of coral reef biological criteria. Research is focused on developing methods and tools to support implementation of legally defensible biological standards for maintaining biological integrity, which is protected by ...

  15. MANGROVE-DERIVED NUTRIENTS AND CORAL REEFS

    Science.gov (United States)

    Understanding the consequences of the declining global cover of mangroves due to anthropogenic disturbance necessitates consideration of how mangrove-derived nutrients contribute to threatened coral reef systems. We sampled potential sources of organic matter and a suite of sessi...

  16. Coral Reef Watch, Nighttime Temperature, 50 km

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Coral Reef Watch provides sea surface temperature (SST) products derived from NOAA's Polar Operational Environmental Satellites (POES). This data provides...

  17. EPA Field Manual for Coral Reef Assessments

    Science.gov (United States)

    The Water Quality Research Program (WQRP) supports development of coral reef biological criteria. Research is focused on developing methods and tools to support implementation of legally defensible biological standards for maintaining biological integrity, which is protected by ...

  18. Coral Reef Watch, Temperature Anomaly, 50 km

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Coral Reef Watch distributes SST anomaly data using a combination of the POES AVHRR Global Area Coverage data, and data from a climatological database. AVHRR...

  19. Tradeoffs between fisheries harvest and the resilience of coral reefs.

    Science.gov (United States)

    Bozec, Yves-Marie; O'Farrell, Shay; Bruggemann, J Henrich; Luckhurst, Brian E; Mumby, Peter J

    2016-04-19

    Many countries are legally obliged to embrace ecosystem-based approaches to fisheries management. Reductions in bycatch and physical habitat damage are now commonplace, but mitigating more sophisticated impacts associated with the ecological functions of target fisheries species are in their infancy. Here we model the impacts of a parrotfish fishery on the future state and resilience of Caribbean coral reefs, enabling us to view the tradeoff between harvest and ecosystem health. We find that the implementation of a simple and enforceable size restriction of >30 cm provides a win:win outcome in the short term, delivering both ecological and fisheries benefits and leading to increased yield and greater coral recovery rate for a given harvest rate. However, maintaining resilient coral reefs even until 2030 requires the addition of harvest limitations (fisheries.

  20. Black reefs: iron-induced phase shifts on coral reefs

    NARCIS (Netherlands)

    Wegley Kelly, L.; Barott, K.L.; Dinsdale, E.; Friedlander, A.M.; Nosrat, B.; Obura, D.; Sala, E.; Sandin, S.A.; Smith, J.E.; Vermeij, M.J.A.; Williams, G.J.; Willner, D.; Rohwer, F.

    2012-01-01

    The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions of the central Pacific. Natural terrestrial run-off of iron is non-existent and aerial deposition is extremely low. However, a number of ship groundings have occurred on these atolls. The reefs surrounding the s

  1. Black reefs: iron-induced phase shifts on coral reefs

    NARCIS (Netherlands)

    Wegley Kelly, L.; Barott, K.L.; Dinsdale, E.; Friedlander, A.M.; Nosrat, B.; Obura, D.; Sala, E.; Sandin, S.A.; Smith, J.E.; Vermeij, M.J.A.; Williams, G.J.; Willner, D.; Rohwer, F.

    2012-01-01

    The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions of the central Pacific. Natural terrestrial run-off of iron is non-existent and aerial deposition is extremely low. However, a number of ship groundings have occurred on these atolls. The reefs surrounding the

  2. Ecological Processes and Contemporary Coral Reef Management

    OpenAIRE

    Angela Dikou

    2010-01-01

    Top-down controls of complex foodwebs maintain the balance among the critical groups of corals, algae, and herbivores, thus allowing the persistence of corals reefs as three-dimensional, biogenic structures with high biodiversity, heterogeneity, resistance, resilience and connectivity, and the delivery of essential goods and services to societies. On contemporary reefs world-wide, however, top-down controls have been weakened due to reduction in herbivory levels (overfishing or disease outbre...

  3. Linking habitat mosaics and connectivity in a coral reef seascape.

    Science.gov (United States)

    McMahon, Kelton W; Berumen, Michael L; Thorrold, Simon R

    2012-09-18

    Tropical marine ecosystems are under mounting anthropogenic pressure from overfishing and habitat destruction, leading to declines in their structure and function on a global scale. Although maintaining connectivity among habitats within a seascape is necessary for preserving population resistance and resilience, quantifying movements of individuals within seascapes remains challenging. Traditional methods of identifying and valuing potential coral reef fish nursery habitats are indirect, often relying on visual surveys of abundance and correlations of size and biomass among habitats. We used compound-specific stable isotope analyses to determine movement patterns of commercially important fish populations within a coral reef seascape. This approach allowed us to quantify the relative contributions of individuals from inshore nurseries to reef populations and identify migration corridors among important habitats. Our results provided direct measurements of remarkable migrations by juvenile snapper of over 30 km, between nurseries and reefs. We also found significant plasticity in juvenile nursery residency. Although a majority of individuals on coastal reefs had used seagrass nurseries as juveniles, many adults on oceanic reefs had settled directly into reef habitats. Moreover, seascape configuration played a critical but heretofore unrecognized role in determining connectivity among habitats. Finally, our approach provides key quantitative data necessary to estimate the value of distinctive habitats to ecosystem services provided by seascapes.

  4. Linking habitat mosaics and connectivity in a coral reef seascape

    KAUST Repository

    McMahon, Kelton

    2012-09-04

    Tropical marine ecosystems are under mounting anthropogenic pressure from overfishing and habitat destruction, leading to declines in their structure and function on a global scale. Although maintaining connectivity among habitats within a seascape is necessary for preserving population resistance and resilience, quantifying movements of individuals within seascapes remains challenging. Traditional methods of identifying and valuing potential coral reef fish nursery habitats are indirect, often relying on visual surveys of abundance and correlations of size and biomass among habitats. We used compound-specific stable isotope analyses to determine movement patterns of commercially important fish populations within a coral reef seascape. This approach allowed us to quantify the relative contributions of individuals from inshore nurseries to reef populations and identify migration corridors among important habitats. Our results provided direct measurements of remarkable migrations by juvenile snapper of over 30 km, between nurseries and reefs. We also found significant plasticity in juvenile nursery residency. Although a majority of individuals on coastal reefs had used seagrass nurseries as juveniles, many adults on oceanic reefs had settled directly into reef habitats. Moreover, seascape con figuration played a critical but heretofore unrecognized role in determining connectivity among habitats. Finally, our approach provides key quantitative data necessary to estimate the value of distinctive habitats to ecosystem services provided by seascapes.

  5. Black reefs: iron-induced phase shifts on coral reefs.

    Science.gov (United States)

    Kelly, Linda Wegley; Barott, Katie L; Dinsdale, Elizabeth; Friedlander, Alan M; Nosrat, Bahador; Obura, David; Sala, Enric; Sandin, Stuart A; Smith, Jennifer E; Vermeij, Mark J A; Williams, Gareth J; Willner, Dana; Rohwer, Forest

    2012-03-01

    The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions of the central Pacific. Natural terrestrial run-off of iron is non-existent and aerial deposition is extremely low. However, a number of ship groundings have occurred on these atolls. The reefs surrounding the shipwreck debris are characterized by high benthic cover of turf algae, macroalgae, cyanobacterial mats and corallimorphs, as well as particulate-laden, cloudy water. These sites also have very low coral and crustose coralline algal cover and are call black reefs because of the dark-colored benthic community and reduced clarity of the overlying water column. Here we use a combination of benthic surveys, chemistry, metagenomics and microcosms to investigate if and how shipwrecks initiate and maintain black reefs. Comparative surveys show that the live coral cover was reduced from 40 to 60% to reefs on Millennium, Tabuaeran and Kingman. These three sites are relatively large (>0.75 km(2)). The phase shift occurs rapidly; the Kingman black reef formed within 3 years of the ship grounding. Iron concentrations in algae tissue from the Millennium black reef site were six times higher than in algae collected from reference sites. Metagenomic sequencing of the Millennium Atoll black reef-associated microbial community was enriched in iron-associated virulence genes and known pathogens. Microcosm experiments showed that corals were killed by black reef rubble through microbial activity. Together these results demonstrate that shipwrecks and their associated iron pose significant threats to coral reefs in iron-limited regions.

  6. Watershed- and island wide-scale land cover changes in Puerto Rico (1930s-2004) and their potential effects on coral reef ecosystems.

    Science.gov (United States)

    Ramos-Scharrón, Carlos E; Torres-Pulliza, Damaris; Hernández-Delgado, Edwin A

    2015-02-15

    Anthropogenically enhanced delivery of sediments and other land-based sources of pollution represent well-recognized threats to nearshore coral reef communities worldwide. Land cover change is commonly used as a proxy to document human-induced alterations to sediment and pollutant delivery rates to coral reef bearing waters. In this article, land cover change was assessed for a 69-km(2) watershed in Puerto Rico between 1936 and 2004 by aerial photograph interpretation. Forests and sugar cane fields predominated from 1936 through the late 1970s, but while cropland dipped to negligible levels by 2004, net forest cover doubled and built-up areas increased tenfold. The watershed-scale land cover changes documented here mimicked those of the entire Puerto Rican landmass. Sediment yield predictions that rely on the sort of land cover changes reported here inevitably result in declining trends, but anecdotal and scientific evidence in the study watershed and throughout Puerto Rico suggests that sediment and pollutant loading rates still remain high and at potentially threatening levels. The simultaneous reduction in living coral cover that accompanied reforestation and urbanization patterns since the 1970s in our study region is discussed here within the context of the following non-mutually exclusive potential explanations: (a) the inability of land cover change-based assessments to discern spatially-focused, yet highly influential sources of sediment; (b) the potentially secondary role of cropland and forest cover changes in influencing nearshore coral reef conditions relative to other types of stressors like those related to climate change; and (c) the potentially dominant role that urban development may have had in altering marine water quality to the extent of reducing live coral cover. Since identification of the causes for coral reef degradation has proven elusive here and elsewhere, we infer that coral reef management may only be effective when numerous land- and

  7. The dynamics of architectural complexity on coral reefs under climate change.

    Science.gov (United States)

    Bozec, Yves-Marie; Alvarez-Filip, Lorenzo; Mumby, Peter J

    2015-01-01

    One striking feature of coral reef ecosystems is the complex benthic architecture which supports diverse and abundant fauna, particularly of reef fish. Reef-building corals are in decline worldwide, with a corresponding loss of live coral cover resulting in a loss of architectural complexity. Understanding the dynamics of the reef architecture is therefore important to envision the ability of corals to maintain functional habitats in an era of climate change. Here, we develop a mechanistic model of reef topographical complexity for contemporary Caribbean reefs. The model describes the dynamics of corals and other benthic taxa under climate-driven disturbances (hurricanes and coral bleaching). Corals have a simplified shape with explicit diameter and height, allowing species-specific calculation of their colony surface and volume. Growth and the mechanical (hurricanes) and biological erosion (parrotfish) of carbonate skeletons are important in driving the pace of extension/reduction in the upper reef surface, the net outcome being quantified by a simple surface roughness index (reef rugosity). The model accurately simulated the decadal changes of coral cover observed in Cozumel (Mexico) between 1984 and 2008, and provided a realistic hindcast of coral colony-scale (1-10 m) changing rugosity over the same period. We then projected future changes of Caribbean reef rugosity in response to global warming. Under severe and frequent thermal stress, the model predicted a dramatic loss of rugosity over the next two or three decades. Critically, reefs with managed parrotfish populations were able to delay the general loss of architectural complexity, as the benefits of grazing in maintaining living coral outweighed the bioerosion of dead coral skeletons. Overall, this model provides the first explicit projections of reef rugosity in a warming climate, and highlights the need of combining local (protecting and restoring high grazing) to global (mitigation of greenhouse gas

  8. Coral reef remote sensing a guide for mapping, monitoring and management

    CERN Document Server

    Goodman, James A; Phinn, Stuart R

    2013-01-01

    This book offers a multi-level examination of remote-sensing technologies for mapping and monitoring coral reef ecosystems, ranging from satellite and airborne imagery to ship-based observation. Includes examples of practical applications of the technologies.

  9. Coral reef microbialites as contemporaneous framework component (deglacial, Tahiti)

    Science.gov (United States)

    Westphal, H.; Heindel, K.; Brandano, M.; Peckmann, J.; Cabioch, G.

    2009-04-01

    Marine microbialites associated with hermatypic corals are known from several intervals of Earth's history, including the latest deglacial from the Pleistocene to the Holocene. In contrast, in the modern world no such massive occurrences are known to form. Here, deglacial microbialites from Tahiti (IODP 310) are studied. The paradox of the co-occurrence of oligotrophic corals with microbialites that tend to form in more nutrient-rich environments has previously led to the assumption that the microbialites are considerably younger than the coral framework, and have formed in deeper storeys of the reef edifice; or that they represent a severe disturbance of the reef ecosystem. The present study in contrast demonstrates that microbialite encrustation occurred immediately after coral demise. Encrustation has taken place under photic conditions, even though the involvement of cyanobacteria or anoxygenic phototrophs in the microbialite precipitation remains elusive. The reason for the voluminous development of microbialites in the deglacial reefs of Tahiti (up to 80% by volume of the cores) remains an open question. High trophic conditions caused by fluvial or groundwater transport from the volcanic hinterland appears to be an unlikely cause, given that the corals and the microbialites developed in close vicinity, and that the coral community prospered continuously - no breaks in the development of the succession were detected. The fact, however, that voluminous deglacial reef microbialites are restricted to volcanic islands, implies that moderately, and possibly episodically elevated trophic conditions favor this type of microbialite formation. Clearly, the reef microbialites recovered in the IODP 310 cores did not develop after a serious disturbance such as drowning or suffocation by terrestrial material, and are no "disaster forms". Rather, their precipitation represents a continuous process in an ecosystem that was on the verge of its limiting conditions.

  10. Coral diseases and bleaching on Colombian Caribbean coral reefs.

    Science.gov (United States)

    Navas-Camacho, Raúl; Gil-Agudelo, Diego Luis; Rodríguez-Ramírez, Alberto; Reyes-Nivia, María Catalina; Garzón-Ferreira, Jaime

    2010-05-01

    Since 1998 the National Monitoring System for the Coral Reefs of Colombia (SIMAC) has monitored the occurrence of coral bleaching and diseases in some Colombian coral reefs (permanent stations at San Andres Island, Rosario Islands, Tayrona, San Bernardo Islands and Urabá). The main purpose is to evaluate their health status and to understand the factors that have been contributing to their decline. To estimate these occurrences, annual surveys in 126 permanent belt transects (10 x 2m) with different depth intervals (3-6 meters, 9-12 meters and 15-18 meters) are performed at all reef sites. Data from the 1998-2004 period, revealed that San Andrés Island had many colonies with diseases (38.9 colonies/m2), and Urabá had high numbers with bleaching (54.4 colonies/m2). Of the seven reported coral diseases studied, Dark Spots Disease (DSD), and White Plague Disease (WPD) were noteworthy because they occurred in all Caribbean monitored sites, and because of their high interannual infection incidence. Thirty five species of scleractinian corals were affected by at least one disease and a high incidence of coral diseases on the main reef builders is documented. Bleaching was present in 34 species. During the whole monitoring period, Agaricia agaricites and Siderastrea siderea were the species most severely affected by DSD and bleaching, respectively. Diseases on species such as Agaricia fragilis, A. grahamae, A. humilis, Diploria clivosa, Eusmilia fastigiata, Millepora complanata, and Mycetophyllia aliciae are recorded for first time in Colombia. We present bleaching and disease incidences, kinds of diseases, coral species affected, reef localities studied, depth intervals of surveys, and temporal (years) variation for each geographic area. This variation makes difficult to clearly determine defined patterns or general trends for monitored reefs. This is the first long-term study of coral diseases and bleaching in the Southwestern Caribbean, and one of the few long

  11. Multiple Stressors and the Functioning of Coral Reefs

    Science.gov (United States)

    Harborne, Alastair R.; Rogers, Alice; Bozec, Yves-Marie; Mumby, Peter J.

    2017-01-01

    Coral reefs provide critical services to coastal communities, and these services rely on ecosystem functions threatened by stressors. By summarizing the threats to the functioning of reefs from fishing, climate change, and decreasing water quality, we highlight that these stressors have multiple, conflicting effects on functionally similar groups of species and their interactions, and that the overall effects are often uncertain because of a lack of data or variability among taxa. The direct effects of stressors on links among functional groups, such as predator-prey interactions, are particularly uncertain. Using qualitative modeling, we demonstrate that this uncertainty of stressor impacts on functional groups (whether they are positive, negative, or neutral) can have significant effects on models of ecosystem stability, and reducing uncertainty is vital for understanding changes to reef functioning. This review also provides guidance for future models of reef functioning, which should include interactions among functional groups and the cumulative effect of stressors.

  12. Can we measure beauty? Computational evaluation of coral reef aesthetics

    NARCIS (Netherlands)

    Haas, A.F.; Guibert, M.; Foerschner, A.; Co, T.; Calhoun, S.; George, E.; Hatay, M.; Dinsdale, E.; Sandin, S.A.; Smith, J.E.; Vermeij, M.J.A.; Felts, B.; Dustan, P.; Salamon, P.; Rohwer, F.

    2015-01-01

    The natural beauty of coral reefs attracts millions of tourists worldwide resulting in substantial revenues for the adjoining economies. Although their visual appearance is a pivotal factor attracting humans to coral reefs current monitoring protocols exclusively target biogeochemical parameters,

  13. Calibration of Community-based Coral Reef Monitoring Protocols ...

    African Journals Online (AJOL)

    Keywords: coral reef monitoring, community-based, calibration. Abstract—Coral reef monitoring (CRM) has been recognised as an important management tool and has ..... Pollution Bulletin 40: 537-550. Wilkinson, C., Green, A., Almany, J. &.

  14. Can we measure beauty? Computational evaluation of coral reef aesthetics

    NARCIS (Netherlands)

    Haas, A.F.; Guibert, M.; Foerschner, A.; Co, T.; Calhoun, S.; George, E.; Hatay, M.; Dinsdale, E.; Sandin, S.A.; Smith, J.E.; Vermeij, M.J.A.; Felts, B.; Dustan, P.; Salamon, P.; Rohwer, F.

    2015-01-01

    The natural beauty of coral reefs attracts millions of tourists worldwide resulting in substantial revenues for the adjoining economies. Although their visual appearance is a pivotal factor attracting humans to coral reefs current monitoring protocols exclusively target biogeochemical parameters, ne

  15. Zonation of uplifted pleistocene coral reefs on barbados, west indies.

    Science.gov (United States)

    Mesolella, K J

    1967-05-05

    The coral species composition of uplifted Pleistocene reefs on Barbados is very similar to Recent West Indian reefs. Acropora palmata, Acropora cervicornis, and Montastrea annularis are qtuantitatively the most important of the coral species.

  16. New protection initiatives announced for coral reefs

    Science.gov (United States)

    Showstack, Randy

    Off the coasts of some of the South Pacific's most idyllic-sounding atolls, Austin Bowden-Kerby has seen first-hand the heavy damage to coral reefs from dynamite and cyanide fishing. For instance, while snorkeling near Chuuk, an island in Micronesia, he has observed craters and rubble beds of coral, which locals have told him date to World War II ordnance.A marine biologist and project scientist for the Coral Gardens Initiative of the Foundation for the Peoples of the South Pacific, Bowden-Kerby has also identified what he says are some public health effects related to destroyed coral reefs and their dying fisheries. These problems include protein and vitamin A deficiency and blindness, all of which may—in some instances—be linked to poor nutrition resulting from lower reef fish consumption by islanders, according to Bowden-Kerby.

  17. Primary production of coral ecosystems in the Vietnamese coastal and adjacent marine waters

    Science.gov (United States)

    Tac-An, Nguyen; Minh-Thu, Phan; Cherbadji, I. I.; Propp, M. V.; Odintsov, V. S.; Propp, L. H.

    2013-11-01

    Coral reef ecosystems in coastal waters and islands of Vietnam have high primary production. Average gross primary production (GPP) in coral reef waters was 0.39 g C m-2 day-1. GPP of corals ranged from 3.12 to 4.37 g C m-2 day-1. GPP of benthic microalgae in coral reefs ranged from 2 to 10 g C m-2 day-1. GPP of macro-algae was 2.34 g C m-2 day-1. Therefore, the total of GPP of whole coral reef ecosystems could reach 7.85 to 17.10 g C m-2 day-1. Almost all values of the ratio of photosynthesis to respiration in the water bodies are higher than 1, which means these regions are autotrophic systems. Wire variation of GPP in coral reefs was contributed by species abundance of coral and organisms, nutrient supports and environmental characteristics of coral ecosystems. Coral reefs play an important ecological role of biogeochemical cycling of nutrients in waters around the reefs. These results contribute valuable information for the protection, conservation and sustainable exploitation of the natural resources in coral reef ecosystems in Vietnam.

  18. The engine of the reef: Photobiology of the coral-algal symbiosis

    Directory of Open Access Journals (Sweden)

    Melissa Susan Roth

    2014-08-01

    Full Text Available Coral reef ecosystems thrive in tropical oligotrophic oceans because of the relationship between corals and endosymbiotic dinoflagellate algae called Symbiodinium. Symbiodinium convert sunlight and carbon dioxide into organic carbon and oxygen to fuel coral growth and calcification, creating habitat for these diverse and productive ecosystems. Light is thus a key regulating factor shaping the productivity, physiology and ecology of the coral holobiont. Similar to all oxygenic photoautotrophs, Symbiodinium must safely harvest sunlight for photosynthesis and dissipate excess energy to prevent oxidative stress. Oxidative stress is caused by environmental stressors such as those associated with global climate change, and ultimately leads to breakdown of the coral-algal symbiosis known as coral bleaching. Recently, large-scale coral bleaching events have become pervasive and frequent threatening and endangering coral reefs. Because the coral-algal symbiosis is the biological engine producing the reef, the future of coral reef ecosystems depends on the ecophysiology of the symbiosis. This review examines the photobiology of the coral-algal symbiosis with particular focus on the photophysiological responses and timescales of corals and Symbiodinium. Additionally, this review summarizes the light environment and its dynamics, the vulnerability of the symbiosis to oxidative stress, the abiotic and biotic factors influencing photosynthesis, the diversity of the coral-algal symbiosis and recent advances in the field. Studies integrating physiology with the developing omics fields will provide new insights into the coral-algal symbiosis. Greater physiological and ecological understanding of the coral-algal symbiosis is needed for protection and conservation of coral reefs.

  19. Feedbacks Between Wave Energy And Declining Coral Reef Structure: Implications For Coastal Morphodynamics

    Science.gov (United States)

    Grady, A. E.; Jenkins, C. J.; Moore, L. J.; Potts, D. C.; Burgess, P. M.; Storlazzi, C. D.; Elias, E.; Reidenbach, M. A.

    2013-12-01

    The incident wave energy dissipated by the structural complexity and bottom roughness of coral reef ecosystems, and the carbonate sediment produced by framework-building corals, provide natural shoreline protection and nourishment, respectively. Globally, coral reef ecosystems are in decline as a result of ocean warming and acidification, which is exacerbated by chronic regional stressors such as pollution and disease. As a consequence of declining reef health, many reef ecosystems are experiencing reduced coral cover and shifts to dominance by macroalgae, resulting in a loss of rugosity and thus hydrodynamic roughness. As coral reef architecture is compromised and carbonate skeletons are eroded, wave energy dissipation and sediment transport patterns--along with the carbonate sediment budget of the coastal environment--may be altered. Using a Delft3D numerical model of the south-central Molokai, Hawaii, fringing reef, we simulate the effects of changing reef states on wave energy and sediment transport. To determine the temporally-varying effects of biotic and abiotic stressors such as storms and bleaching on the reef structure and carbonate production, we couple Delft3D with CarboLOT, a model that simulates growth and competition of carbonate-producing organisms. CarboLOT is driven by the Lotka-Volterra population ecology equations and niche suitability principles, and accesses the CarboKB database for region-specific, carbonate-producing species information on growth rates, reproduction patterns, habitat suitability, as well as organism geometries. Simulations assess how changing reef states--which alter carbonate sediment production and reef morphology and thus hydrodynamic roughness--impact wave attenuation and sediment transport gradients along reef-fronted beaches. Initial results suggest that along fringing reefs having characteristics similar to the Molokai fringing reef, projected sea level rise will likely outpace coral reef accretion, and the increased

  20. Fitness consequences of habitat variability, trophic position, and energy allocation across the depth distribution of a coral-reef fish

    Science.gov (United States)

    Goldstein, E. D.; D'Alessandro, E. K.; Sponaugle, S.

    2017-09-01

    Environmental clines such as latitude and depth that limit species' distributions may be associated with gradients in habitat suitability that can affect the fitness of an organism. With the global loss of shallow-water photosynthetic coral reefs, mesophotic coral ecosystems ( 30-150 m) may be buffered from some environmental stressors, thereby serving as refuges for a range of organisms including mobile obligate reef dwellers. Yet habitat suitability may be diminished at the depth boundary of photosynthetic coral reefs. We assessed the suitability of coral-reef habitats across the majority of the depth distribution of a common demersal reef fish ( Stegastes partitus) ranging from shallow shelf (SS, reefs are suitable habitats for demersal reef fish and may be important refuges for organisms common on declining shallow coral reefs.

  1. Expanding marine protected areas to include degraded coral reefs.

    Science.gov (United States)

    Abelson, A; Nelson, P A; Edgar, G J; Shashar, N; Reed, D C; Belmaker, J; Krause, G; Beck, M W; Brokovich, E; France, R; Gaines, S D

    2016-12-01

    Marine protected areas (MPAs) are a commonly applied solution to coral reef degradation, yet coral reefs continue to decline worldwide. We argue that expanding the range of MPAs to include degraded reefs (DR-MPA) could help reverse this trend. This approach requires new ecological criteria for MPA design, siting, and management. Rather than focusing solely on preserving healthy reefs, our approach focuses on the potential for biodiversity recovery and renewal of ecosystem services. The new criteria would help identify sites with the highest potential for recovery and the greatest resistance to future threats (e.g., increased temperature and acidification) and sites that contribute to MPA connectivity. The DR-MPA approach is a compliment rather than a substitute for traditional MPA design approaches. We believe that the DR-MPA approach can enhance the natural, or restoration-assisted, recovery of DRs and their ecosystem services; increase total reef area available for protection; promote more resilient and better-connected MPA networks; and improve conditions for human communities dependent on MPA ecosystem services. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  2. Persistence and change in community composition of reef corals through present, past, and future climates.

    Directory of Open Access Journals (Sweden)

    Peter J Edmunds

    Full Text Available The reduction in coral cover on many contemporary tropical reefs suggests a different set of coral community assemblages will dominate future reefs. To evaluate the capacity of reef corals to persist over various time scales, we examined coral community dynamics in contemporary, fossil, and simulated future coral reef ecosystems. Based on studies between 1987 and 2012 at two locations in the Caribbean, and between 1981 and 2013 at five locations in the Indo-Pacific, we show that many coral genera declined in abundance, some showed no change in abundance, and a few coral genera increased in abundance. Whether the abundance of a genus declined, increased, or was conserved, was independent of coral family. An analysis of fossil-reef communities in the Caribbean revealed changes in numerical dominance and relative abundances of coral genera, and demonstrated that neither dominance nor taxon was associated with persistence. As coral family was a poor predictor of performance on contemporary reefs, a trait-based, dynamic, multi-patch model was developed to explore the phenotypic basis of ecological performance in a warmer future. Sensitivity analyses revealed that upon exposure to thermal stress, thermal tolerance, growth rate, and longevity were the most important predictors of coral persistence. Together, our results underscore the high variation in the rates and direction of change in coral abundances on contemporary and fossil reefs. Given this variation, it remains possible that coral reefs will be populated by a subset of the present coral fauna in a future that is warmer than the recent past.

  3. Multiple Stressors and Ecological Complexity Require A New Approach to Coral Reef Research

    Directory of Open Access Journals (Sweden)

    Linwood Hagan Pendleton

    2016-03-01

    Full Text Available Ocean acidification, climate change, and other environmental stressors threaten coral reef ecosystems and the people who depend upon them. New science reveals that these multiple stressors interact and may affect a multitude of physiological and ecological processes in complex ways. The interaction of multiple stressors and ecological complexity may mean that the negative effects on coral reef ecosystems will happen sooner and be more severe than previously thought. Yet, most research on the effects of global change on coral reefs focus on one or few stressors and pathways or outcomes (e.g. bleaching. Based on a critical review of the literature, we call for a regionally targeted strategy of mesocosm-level research that addresses this complexity and provides more realistic projections about coral reef impacts in the face of global environmental change. We believe similar approaches are needed for other ecosystems that face global environmental change.

  4. Developing a multi-stressor gradient for coral reefs

    Science.gov (United States)

    Coral reefs are often found near coastal waters where multiple anthropogenic stressors co-occur at areas of human disturbance. Developing coral reef biocriteria under the U.S. Clean Water Act requires relationships between anthropogenic stressors and coral reef condition to be es...

  5. Coral Reefs: A Gallery Program, Grades 7-12.

    Science.gov (United States)

    National Aquarium in Baltimore, MD. Dept. of Education.

    Gallery classes at the National Aquarium in Baltimore give the opportunity to study specific aquarium exhibits which demonstrate entire natural habitats. The coral reef gallery class features the gigantic western Atlantic coral reef (325,000 gallons) with over 1,000 fish. The exhibit simulates a typical Caribbean coral reef and nearby sandy…

  6. Coral Reefs: A Gallery Program, Grades 7-12.

    Science.gov (United States)

    National Aquarium in Baltimore, MD. Dept. of Education.

    Gallery classes at the National Aquarium in Baltimore give the opportunity to study specific aquarium exhibits which demonstrate entire natural habitats. The coral reef gallery class features the gigantic western Atlantic coral reef (325,000 gallons) with over 1,000 fish. The exhibit simulates a typical Caribbean coral reef and nearby sandy…

  7. Developing a multi-stressor gradient for coral reefs

    Science.gov (United States)

    Coral reefs are often found near coastal waters where multiple anthropogenic stressors co-occur at areas of human disturbance. Developing coral reef biocriteria under the U.S. Clean Water Act requires relationships between anthropogenic stressors and coral reef condition to be es...

  8. Climate change, global warming and coral reefs: modelling the effects of temperature.

    Science.gov (United States)

    Crabbe, M James C

    2008-10-01

    Climate change and global warming have severe consequences for the survival of scleractinian (reef-building) corals and their associated ecosystems. This review summarizes recent literature on the influence of temperature on coral growth, coral bleaching, and modelling the effects of high temperature on corals. Satellite-based sea surface temperature (SST) and coral bleaching information available on the internet is an important tool in monitoring and modelling coral responses to temperature. Within the narrow temperature range for coral growth, corals can respond to rate of temperature change as well as to temperature per se. We need to continue to develop models of how non-steady-state processes such as global warming and climate change will affect coral reefs.

  9. Damages of coral reef ecosystem by the giant clam excavation--- a case study on North Reef of Xisha Islands%砗磲采挖对珊瑚礁生态系统的破坏--以西沙北礁为例

    Institute of Scientific and Technical Information of China (English)

    李元超; 韩有定; 陈石泉; 谢海群; 陈孝; 周治东

    2015-01-01

    The variations of coral reefs was compared before and after the excavation of giant clams on North Reef of Xisha Islands to illustrate the destructions on the coral reef ecosystem.The results showed that 29 coral species dis-appeared on the reef flat of North Reef in 2014 compared to that in 2012.Dominant species evolved from previous Acropora sp.to Montipora digitata.The diversity index of corals became low in the reef flat.Although North Reef maintained 52.83% of mean coral coverage,around 10% reduction in coral coverage was found in 2014 compared with that in 2012.Particularly,the coral coverage was reduced as much as 20% with bleaching corals at station 2. The findings suggest that North Reef,especially the reef flat,has suffered severe damages.As results,the numbers of coral species were deceased and the community structure altered besides the deceased of species diversity and coral coverage and increased of coral mortality.It is considered that the coral reef degradation on North Reef is re-sulted from the illegal excavation of giant clams,which is an important factor destroyed and threatened the health of coral reef ecosystem in the flat.%以西沙群岛北礁为例,通过对比采挖砗磲前后的数据,来说明该活动对珊瑚礁生态系统的破坏.2012~2014年间北礁礁坪上的造礁石珊瑚种类数量变动较大,减少了29种;优势种由之前的鹿角珊瑚(Acropora sp.)变为现在的指状蔷薇珊瑚(Montipora digitata);礁坪的物种多样性指数也处于较低的水平.虽然当前北礁的珊瑚覆盖率为52.83%,但是相比2012年降低了大约10%,尤其是2号站位,珊瑚覆盖率降低了约20%.同时2号站位出现了珊瑚白化死亡的现象.调查结果表明,北礁的珊瑚礁生态系统,尤其是礁坪上的珊瑚礁生态系统已经受到严重的破坏,珊瑚种类减少、群落结构改变、物种多样性降低、覆盖率下降、死亡率提高.通过分析

  10. Impact Of Coral Structures On Wave Directional Spreading Across A Shallow Reef Flat - Lizard Island, Northern Great Barrier Reef

    Science.gov (United States)

    Leon, J. X.; Baldock, T.; Callaghan, D. P.; Hoegh-guldberg, O.; Mumby, P.; Phinn, S. R.; Roelfsema, C. M.; Saunders, M. I.

    2013-12-01

    Coral reef hydrodynamics operate at several and overlapping spatial-temporal scales. Waves have the most important forcing function on shallow (stress, directly mixing water (temperature and nutrients) and transporting sediments, nutrients and plankton. Reef flats are very effective at dissipating wave energy and providing an important ecosystem service by protecting highly valued shorelines. The effectiveness of reef flats to dissipate wave energy is related to the extreme hydraulic roughness of the benthos and substrate composition. Hydraulic roughness is usually obtained empirically from frictional-dissipation calculations, as detailed field measurements of bottom roughness (e.g. chain-method or profile gauges) is a very labour and time-consuming task. In this study we measured the impact of coral structures on wave directional spreading. Field data was collected during October 2012 across a reef flat on Lizard Island, northern Great Barrier Reef. Wave surface levels were measured using an array of self-logging pressure sensors. A rapid in situ close-range photogrammetric method was used to create a high-resolution (0.5 cm) image mosaic and digital elevation model. Individual coral heads were extracted from these datasets using geo-morphometric and object-based image analysis techniques. Wave propagation was modelled using a modified version of the SWAN model which includes the measured coral structures in 2m by 1m cells across the reef. The approach followed a cylinder drag approach, neglecting skin friction and inertial components. Testing against field data included bed skin friction. Our results show, for the first time, how the variability of the reef benthos structures affects wave dissipation across a shallow reef flat. This has important implications globally for coral reefs, due to the large extent of their area occupied by reef flats, particularly, as global-scale degradation in coral reef health is causing a lowering of reef carbonate production that

  11. Ecological Processes and Contemporary Coral Reef Management

    Directory of Open Access Journals (Sweden)

    Angela Dikou

    2010-05-01

    Full Text Available Top-down controls of complex foodwebs maintain the balance among the critical groups of corals, algae, and herbivores, thus allowing the persistence of corals reefs as three-dimensional, biogenic structures with high biodiversity, heterogeneity, resistance, resilience and connectivity, and the delivery of essential goods and services to societies. On contemporary reefs world-wide, however, top-down controls have been weakened due to reduction in herbivory levels (overfishing or disease outbreak while bottom-up controls have increased due to water quality degradation (increase in sediment and nutrient load and climate forcing (seawater warming and acidification leading to algal-dominated alternate benthic states of coral reefs, which are indicative of a trajectory towards ecological extinction. Management to reverse common trajectories of degradation for coral reefs necessitates a shift from optimization in marine resource use and conservation towards building socio-economic resilience into coral reef systems while attending to the most manageable human impacts (fishing and water quality and the global-scale causes (climate change.

  12. Discovery of a living coral reef in the coastal waters of Iraq.

    Science.gov (United States)

    Pohl, Thomas; Al-Muqdadi, Sameh W; Ali, Malik H; Fawzi, Nadia Al-Mudaffar; Ehrlich, Hermann; Merkel, Broder

    2014-03-06

    Until now, it has been well-established that coral complex in the Arabian/Persian Gulf only exist in the coastal regions of Bahrain, Iran, Kuwait, Oman, Qatar, Saudi Arabia, and United Arab Emirates and it was thought that there are no coral reefs in Iraq. However, here for the first time we show the existence of a living 28 km(2) large coral reef in this country. These corals are adapted to one of the most extreme coral-bearing environments on earth: the seawater temperature in this area ranges between 14 and 34°C. The discovery of the unique coral reef oasis in the turbid coastal waters of Iraq will stimulate the interest of governmental agencies, environmental organizations, as well as of the international scientific community working on the fundamental understanding of coral marine ecosystems and global climate today.

  13. Object-based image analysis for mapping geomorphic zones of coral reefs in the Xisha Islands, China

    Institute of Scientific and Technical Information of China (English)

    XU Jingping; ZHAO Jianhua; LI Fang; WANG Lin; SONG Derui; WEN Shiyong; WANG Fei; GAO Ning

    2016-01-01

    Mapping regional spatial patterns of coral reef geomorphology provides the primary information to understand the constructive processes in the reef ecosystem. However, this work is challenged by the pixel-based image classification method for its comparatively low accuracy. In this paper, an object-based image analysis (OBIA) method was presented to map intra-reef geomorphology of coral reefs in the Xisha Islands, China using Landsat 8 satellite imagery. Following the work of the Millennium Coral Reef Mapping Project, a regional reef class hierarchy with ten geomorphic classes was first defined. Then, incorporating the hierarchical concept and integrating the spectral and additional spatial information such as context, shape and contextual relationships, a large-scale geomorphic map was produced by OBIA with accuracies generally more than 80%. Although the robustness of OBIA has been validated in the applications of coral reef mapping from individual reefs to reef system in this paper, further work is still required to improve its transferability.

  14. Working with, not against, coral-reef fisheries

    Science.gov (United States)

    Birkeland, Charles

    2017-03-01

    The fisheries policies of some Pacific island nations are more appropriate to the biology of their resources than are some of the fisheries policies of more industrialized countries. Exclusive local ownership of natural resources in Palau encourages adjustive management on biologically relevant scales of time and space and promotes responsibility by reducing the tragedy of the commons. The presence of large individuals in fish populations and adequate size of spawning aggregations are more efficient and meaningful cues for timely management than are surveys of abundance or biomass. Taking fish from populations more than halfway to their carrying capacity is working favorably with the fishery because removing fish potentially increases resource stability by negative feedback between stock size and population production. Taking the same amount of fish from a population below half its carrying capacity is working against the fishery, making the population unstable, because reducing the reproductive stock potentially accelerates reduction of the population production by positive feedback. Reef fish are consumed locally, while Palauan laws ban the export of reef resources. This is consistent with the high gross primary production with little excess net production from undisturbed coral-reef ecosystems. The relatively rapid growth rates, short life spans, reliable recruitment and wide-ranging movements of open-ocean fishes such as scombrids make them much more productive than coral-reef fishes. The greater fisheries yield per square kilometer in the open ocean multiplied by well over a thousand times the area of the exclusive economic zone than that of Palau's coral reefs should encourage Palauans to keep reef fishes for subsistence and to feed tourists open-ocean fishes. Fisheries having only artisanal means should be encouraged to increase the yield and sustainability by moving away from coral reefs to bulk harvesting of nearshore pelagics.

  15. Coral reef evolution on rapidly subsiding margins

    Science.gov (United States)

    Webster, J.M.; Braga, J.C.; Clague, D.A.; Gallup, C.; Hein, J.R.; Potts, D.C.; Renema, W.; Riding, R.; Riker-Coleman, K.; Silver, E.; Wallace, L.M.

    2009-01-01

    A series of well-developed submerged coral reefs are preserved in the Huon Gulf (Papua New Guinea) and around Hawaii. Despite different tectonics settings, both regions have experienced rapid subsidence (2-6??m/ka) over the last 500??ka. Rapid subsidence, combined with eustatic sea-level changes, is responsible for repeated drowning and backstepping of coral reefs over this period. Because we can place quantitative constraints on these systems (i.e., reef drowning age, eustatic sea-level changes, subsidence rates, accretion rates, basement substrates, and paleobathymetry), these areas represent unique natural laboratories for exploring the roles of tectonics, reef accretion, and eustatic sea-level changes in controlling the evolution of individual reefs, as well as backstepping of the entire system. A review of new and existing bathymetric, radiometric, sedimentary facies and numerical modeling data indicate that these reefs have had long, complex growth histories and that they are highly sensitive, recording drowning not only during major deglaciations, but also during high-frequency, small-amplitude interstadial and deglacial meltwater pulse events. Analysis of five generalized sedimentary facies shows that reef drowning is characterized by a distinct biological and sedimentary sequence. Observational and numerical modeling data indicate that on precessional (20??ka) and sub-orbital timescales, the rate and amplitude of eustatic sea-level changes are critical in controlling initiation, growth, drowning or sub-aerial exposure, subsequent re-initiation, and final drowning. However, over longer timescales (> 100-500??ka) continued tectonic subsidence and basement substrate morphology influence broad scale reef morphology and backstepping geometries. Drilling of these reefs will yield greatly expanded stratigraphic sections compared with similar reefs on slowly subsiding, stable and uplifting margins, and thus they represent a unique archive of sea-level and climate

  16. Water column correction for coral reef studies by remote sensing.

    Science.gov (United States)

    Zoffoli, Maria Laura; Frouin, Robert; Kampel, Milton

    2014-09-11

    Human activity and natural climate trends constitute a major threat to coral reefs worldwide. Models predict a significant reduction in reef spatial extension together with a decline in biodiversity in the relatively near future. In this context, monitoring programs to detect changes in reef ecosystems are essential. In recent years, coral reef mapping using remote sensing data has benefited from instruments with better resolution and computational advances in storage and processing capabilities. However, the water column represents an additional complexity when extracting information from submerged substrates by remote sensing that demands a correction of its effect. In this article, the basic concepts of bottom substrate remote sensing and water column interference are presented. A compendium of methodologies developed to reduce water column effects in coral ecosystems studied by remote sensing that include their salient features, advantages and drawbacks is provided. Finally, algorithms to retrieve the bottom reflectance are applied to simulated data and actual remote sensing imagery and their performance is compared. The available methods are not able to completely eliminate the water column effect, but they can minimize its influence. Choosing the best method depends on the marine environment, available input data and desired outcome or scientific application.

  17. Fishing degrades size structure of coral reef fish communities.

    Science.gov (United States)

    Robinson, James P W; Williams, Ivor D; Edwards, Andrew M; McPherson, Jana; Yeager, Lauren; Vigliola, Laurent; Brainard, Russell E; Baum, Julia K

    2017-03-01

    Fishing pressure on coral reef ecosystems has been frequently linked to reductions of large fishes and reef fish biomass. Associated impacts on overall community structure are, however, less clear. In size-structured aquatic ecosystems, fishing impacts are commonly quantified using size spectra, which describe the distribution of individual body sizes within a community. We examined the size spectra and biomass of coral reef fish communities at 38 US-affiliated Pacific islands that ranged in human presence from near pristine to human population centers. Size spectra 'steepened' steadily with increasing human population and proximity to market due to a reduction in the relative biomass of large fishes and an increase in the dominance of small fishes. Reef fish biomass was substantially lower on inhabited islands than uninhabited ones, even at inhabited islands with the lowest levels of human presence. We found that on populated islands size spectra exponents decreased (analogous to size spectra steepening) linearly with declining biomass, whereas on uninhabited islands there was no relationship. Size spectra were steeper in regions of low sea surface temperature but were insensitive to variation in other environmental and geomorphic covariates. In contrast, reef fish biomass was highly sensitive to oceanographic conditions, being influenced by both oceanic productivity and sea surface temperature. Our results suggest that community size structure may be a more robust indicator than fish biomass to increasing human presence and that size spectra are reliable indicators of exploitation impacts across regions of different fish community compositions, environmental drivers, and fisheries types. Size-based approaches that link directly to functional properties of fish communities, and are relatively insensitive to abiotic variation across biogeographic regions, offer great potential for developing our understanding of fishing impacts in coral reef ecosystems. © 2016

  18. Status and trends of Caribbean coral reefs: 1970-2012

    Science.gov (United States)

    Jackson, Jeremy; Donovan, Mary; Cramer, Katie; Lam, Vivian

    2014-01-01

    vigorously communicate results in simple and straightforward terms to foster more effective conservation and management. This and subsequent reports will focus on separate biogeographic regions in a stepwise fashion and combine all of the results for a global synthesis in the coming years. We began in the wide Caribbean region because the historical data are so extensive and to refine methods of analysis before moving on to other regions. This report documents quantitative trends for Caribbean reef corals, macroalgae, sea urchins, and fishes based on data from 90 reef locations over the past 43 tears. This is the first report to combine all these disparate kinds of data in a single place to explore how the different major components of coral reef ecosystems interact on a broadly regional oceanic scale. We obtained data from more than 35,000 ecological surveys carried out by 78 principal investigators (PIs) and some 200 colleagues working in 34 countries, states, and territories throughout the wide Caribbean region. We conducted two workshops in Panama and Brisbane, Australia to bring together people who provided the data to assist in data quality control, analysis, and synthesis. The first workshop at the Smithsonian Tropical Research Institute (STRI) in the Republic of Panama 29 April to 5 May, 2012 included scientists from 18 countries and territories to verify and expand the database and to conduct exploratory analyses of status and trends. Preliminary results based on the Panama workshop were presented to the DC Marine Community and Smithsonian Institution Senate of Scientists in May 2012 and at the International Coral Reef Symposium (ICRS) and annual ICRI meeting in Cairns, Australia in July 2012. The second workshop in Brisbane, Australia in December 2012 brought together eight coral reef scientists for more detailed data analysis and organization of results for this report and subsequent publications. Subsequent presentations to solicit comments while the report was

  19. Coral larvae move toward reef sounds.

    Directory of Open Access Journals (Sweden)

    Mark J A Vermeij

    Full Text Available Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm that influence settlement success are difficult to observe in situ and are therefore largely unknown. Here, we show that coral larvae respond to acoustic cues that may facilitate detection of habitat from large distances and from upcurrent of preferred settlement locations. Using in situ choice chambers, we found that settling coral larvae were attracted to reef sounds, produced mainly by fish and crustaceans, which we broadcast underwater using loudspeakers. Our discovery that coral larvae can detect and respond to sound is the first description of an auditory response in the invertebrate phylum Cnidaria, which includes jellyfish, anemones, and hydroids as well as corals. If, like settlement-stage reef fish and crustaceans, coral larvae use reef noise as a cue for orientation, the alleviation of noise pollution in the marine environment may gain further urgency.

  20. Reassessing the trophic role of reef sharks as apex predators on coral reefs

    Science.gov (United States)

    Frisch, Ashley J.; Ireland, Matthew; Rizzari, Justin R.; Lönnstedt, Oona M.; Magnenat, Katalin A.; Mirbach, Christopher E.; Hobbs, Jean-Paul A.

    2016-06-01

    Apex predators often have strong top-down effects on ecosystem components and are therefore a priority for conservation and management. Due to their large size and conspicuous predatory behaviour, reef sharks are typically assumed to be apex predators, but their functional role is yet to be confirmed. In this study, we used stomach contents and stable isotopes to estimate diet, trophic position and carbon sources for three common species of reef shark ( Triaenodon obesus, Carcharhinus melanopterus and C. amblyrhynchos) from the Great Barrier Reef (Australia) and evaluated their assumed functional role as apex predators by qualitative and quantitative comparisons with other sharks and large predatory fishes. We found that reef sharks do not occupy the apex of coral reef food chains, but instead have functional roles similar to those of large predatory fishes such as snappers, emperors and groupers, which are typically regarded as high-level mesopredators. We hypothesise that a degree of functional redundancy exists within this guild of predators, potentially explaining why shark-induced trophic cascades are rare or subtle in coral reef ecosystems. We also found that reef sharks participate in multiple food webs (pelagic and benthic) and are sustained by multiple sources of primary production. We conclude that large conspicuous predators, be they elasmobranchs or any other taxon, should not axiomatically be regarded as apex predators without thorough analysis of their diet. In the case of reef sharks, our dietary analyses suggest they should be reassigned to an alternative trophic group such as high-level mesopredators. This change will facilitate improved understanding of how reef communities function and how removal of predators (e.g., via fishing) might affect ecosystem properties.

  1. Processes Driving Natural Acidification of Western Pacific Coral Reef Waters

    Science.gov (United States)

    Shamberger, K. E.; Cohen, A. L.; Golbuu, Y.; McCorkle, D. C.; Lentz, S. J.; Barkley, H. C.

    2013-12-01

    Rising levels of atmospheric carbon dioxide (CO2) are acidifying the oceans, reducing seawater pH, aragonite saturation state (Ωar) and the availability of carbonate ions (CO32-) that calcifying organisms use to build coral reefs. Today's most extensive reef ecosystems are located where open ocean CO32- concentration ([CO32-]) and Ωar exceed 200 μmol kg-1 and 3.3, respectively. However, high rates of biogeochemical cycling and long residence times of water can result in carbonate chemistry conditions within coral reef systems that differ greatly from those of nearby open ocean waters. In the Palauan archipelago, water moving across the reef platform is altered by both biological and hydrographic processes that combine to produce seawater pH, Ωar, [CO32-] significantly lower than that of open ocean source water. Just inshore of the barrier reefs, average Ωar values are 0.2 to 0.3 and pH values are 0.02 to 0.03 lower than they are offshore, declining further as water moves across the back reef, lagoon and into the meandering bays and inlets that characterize the Rock Islands. In the Rock Island bays, coral communities inhabit seawater with average Ωar values of 2.7 or less, and as low as 1.9. Levels of Ωar as low as these are not predicted to occur in the western tropical Pacific open ocean until near the end of the century. Calcification by coral reef organisms is the principal biological process responsible for lowering Ωar and pH, accounting for 68 - 99 % of the difference in Ωar between offshore source water and reef water at our sites. However, in the Rock Island bays where Ωar is lowest, CO2 production by net respiration contributes between 17 - 30 % of the difference in Ωar between offshore source water and reef water. Furthermore, the residence time of seawater in the Rock Island bays is much longer than at the well flushed exposed sites, enabling calcification and respiration to drive Ωar to very low levels despite lower net ecosystem

  2. Changes in coral reef communities across a natural gradient in seawater pH.

    Science.gov (United States)

    Barkley, Hannah C; Cohen, Anne L; Golbuu, Yimnang; Starczak, Victoria R; DeCarlo, Thomas M; Shamberger, Kathryn E F

    2015-06-01

    Ocean acidification threatens the survival of coral reef ecosystems worldwide. The negative effects of ocean acidification observed in many laboratory experiments have been seen in studies of naturally low-pH reefs, with little evidence to date for adaptation. Recently, we reported initial data suggesting that low-pH coral communities of the Palau Rock Islands appear healthy despite the extreme conditions in which they live. Here, we build on that observation with a comprehensive statistical analysis of benthic communities across Palau's natural acidification gradient. Our analysis revealed a shift in coral community composition but no impact of acidification on coral richness, coralline algae abundance, macroalgae cover, coral calcification, or skeletal density. However, coral bioerosion increased 11-fold as pH decreased from the barrier reefs to the Rock Island bays. Indeed, a comparison of the naturally low-pH coral reef systems studied so far revealed increased bioerosion to be the only consistent feature among them, as responses varied across other indices of ecosystem health. Our results imply that whereas community responses may vary, escalation of coral reef bioerosion and acceleration of a shift from net accreting to net eroding reef structures will likely be a global signature of ocean acidification.

  3. Coping with commitment: projected thermal stress on coral reefs under different future scenarios.

    Directory of Open Access Journals (Sweden)

    Simon D Donner

    Full Text Available BACKGROUND: Periods of anomalously warm ocean temperatures can lead to mass coral bleaching. Past studies have concluded that anthropogenic climate change may rapidly increase the frequency of these thermal stress events, leading to declines in coral cover, shifts in the composition of corals and other reef-dwelling organisms, and stress on the human populations who depend on coral reef ecosystems for food, income and shoreline protection. The ability of greenhouse gas mitigation to alter the near-term forecast for coral reefs is limited by the time lag between greenhouse gas emissions and the physical climate response. METHODOLOGY/PRINCIPAL FINDINGS: This study uses observed sea surface temperatures and the results of global climate model forced with five different future emissions scenarios to evaluate the "committed warming" for coral reefs worldwide. The results show that the physical warming commitment from current accumulation of greenhouse gases in the atmosphere could cause over half of the world's coral reefs to experience harmfully frequent (p> or =0.2 year(-1 thermal stress by 2080. An additional "societal" warming commitment, caused by the time required to shift from a business-as-usual emissions trajectory to a 550 ppm CO(2 stabilization trajectory, may cause over 80% of the world's coral reefs to experience harmfully frequent events by 2030. Thermal adaptation of 1.5 degrees C would delay the thermal stress forecast by 50-80 years. CONCLUSIONS/SIGNIFICANCE: The results suggest that adaptation -- via biological mechanisms, coral community shifts and/or management interventions -- could provide time to change the trajectory of greenhouse gas emissions and possibly avoid the recurrence of harmfully frequent events at the majority (97% of the world's coral reefs this century. Without any thermal adaptation, atmospheric CO(2 concentrations may need to be stabilized below current levels to avoid the degradation of coral reef ecosystems

  4. Caribbean-wide decline in carbonate production threatens coral reef growth.

    Science.gov (United States)

    Perry, Chris T; Murphy, Gary N; Kench, Paul S; Smithers, Scott G; Edinger, Evan N; Steneck, Robert S; Mumby, Peter J

    2013-01-01

    Global-scale deteriorations in coral reef health have caused major shifts in species composition. One projected consequence is a lowering of reef carbonate production rates, potentially impairing reef growth, compromising ecosystem functionality and ultimately leading to net reef erosion. Here, using measures of gross and net carbonate production and erosion from 19 Caribbean reefs, we show that contemporary carbonate production rates are now substantially below historical (mid- to late-Holocene) values. On average, current production rates are reduced by at least 50%, and 37% of surveyed sites were net erosional. Calculated accretion rates (mm year(-1)) for shallow fore-reef habitats are also close to an order of magnitude lower than Holocene averages. A live coral cover threshold of ~10% appears critical to maintaining positive production states. Below this ecological threshold carbonate budgets typically become net negative and threaten reef accretion. Collectively, these data suggest that recent ecological declines are now suppressing Caribbean reef growth potential.

  5. Octocoral Species Assembly and Coexistence in Caribbean Coral Reefs.

    Directory of Open Access Journals (Sweden)

    Johanna Velásquez

    Full Text Available What are the determinant factors of community assemblies in the most diverse ecosystem in the ocean? Coral reefs can be divided in continental (i.e., reefs that develop on the continental shelf, including siliciclastic reefs and oceanic (i.e., far off the continental shelf, usually on volcanic substratum; whether or not these habitat differences impose community-wide ecological divergence or species exclusion/coexistence with evolutionary consequences, is unknown.Studying Caribbean octocorals as model system, we determined the phylogenetic community structure in a coral reef community, making emphasis on species coexistence evidenced on trait evolution and environmental feedbacks. Forty-nine species represented in five families constituted the species pool from which a phylogenetic tree was reconstructed using mtDNA. We included data from 11 localities in the Western Caribbean (Colombia including most reef types. To test diversity-environment and phenotype-environment relationships, phylogenetic community structure and trait evolution we carried out comparative analyses implementing ecological and evolutionary approaches.Phylogenetic inferences suggest clustering of oceanic reefs (e.g., atolls contrasting with phylogenetic overdispersion of continental reefs (e.g., reefs banks. Additionally, atolls and barrier reefs had the highest species diversity (Shannon index whereas phylogenetic diversity was higher in reef banks. The discriminant component analysis supported this differentiation between oceanic and continental reefs, where continental octocoral species tend to have greater calyx apertures, thicker branches, prominent calyces and azooxanthellate species. This analysis also indicated a clear separation between the slope and the remaining habitats, caused by the presence or absence of Symbiodinium. K statistic analysis showed that this trait is conserved as well as the branch shape.There was strong octocoral community structure with opposite

  6. Octocoral Species Assembly and Coexistence in Caribbean Coral Reefs.

    Science.gov (United States)

    Velásquez, Johanna; Sánchez, Juan A

    2015-01-01

    What are the determinant factors of community assemblies in the most diverse ecosystem in the ocean? Coral reefs can be divided in continental (i.e., reefs that develop on the continental shelf, including siliciclastic reefs) and oceanic (i.e., far off the continental shelf, usually on volcanic substratum); whether or not these habitat differences impose community-wide ecological divergence or species exclusion/coexistence with evolutionary consequences, is unknown. Studying Caribbean octocorals as model system, we determined the phylogenetic community structure in a coral reef community, making emphasis on species coexistence evidenced on trait evolution and environmental feedbacks. Forty-nine species represented in five families constituted the species pool from which a phylogenetic tree was reconstructed using mtDNA. We included data from 11 localities in the Western Caribbean (Colombia) including most reef types. To test diversity-environment and phenotype-environment relationships, phylogenetic community structure and trait evolution we carried out comparative analyses implementing ecological and evolutionary approaches. Phylogenetic inferences suggest clustering of oceanic reefs (e.g., atolls) contrasting with phylogenetic overdispersion of continental reefs (e.g., reefs banks). Additionally, atolls and barrier reefs had the highest species diversity (Shannon index) whereas phylogenetic diversity was higher in reef banks. The discriminant component analysis supported this differentiation between oceanic and continental reefs, where continental octocoral species tend to have greater calyx apertures, thicker branches, prominent calyces and azooxanthellate species. This analysis also indicated a clear separation between the slope and the remaining habitats, caused by the presence or absence of Symbiodinium. K statistic analysis showed that this trait is conserved as well as the branch shape. There was strong octocoral community structure with opposite diversity

  7. Coral reef surveys in India

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.

    with those practiced elsewhere. With these objectives, diversification of observations to include various reef responses both at community level and at organism level have just begun and may eventually be continued to integrate with global reef monitoring...

  8. NOAA's Coral Reef Conservation Program: Coral Reef Habitat Mapping Projects in 2016

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Maps are a critical cornerstone of coral reef management, research and planning, with direct links to management needs in a number of forms. To accurately...

  9. Surviving in a marine desert: The sponge loop retains resources within coral reefs

    NARCIS (Netherlands)

    de Goeij, J.M.; van Oevelen, D.; Vermeij, M.J.A.; Osinga , R.; Middelburg, J.J.; de Goeij, A.F.P.M.; Admiraal, W.

    2013-01-01

    Ever since Darwin’s early descriptions of coral reefs, scientists have debated how one of the world’s most productive and diverse ecosystems can thrive in the marine equivalent of a desert. It is an enigma how the flux of dissolved organic matter (DOM), the largest resource produced on reefs, is tra

  10. Surviving in a marine desert: the sponge loop retains resources within coral reefs

    NARCIS (Netherlands)

    de Goei, J.M.; van Oevelen, D.; Vermeij, M.J.A.; Osinga, R.; Middelburg, J.J.; de Goei, A.F.P.M.; Admiraal, W.

    2013-01-01

    Ever since Darwin’s early descriptions of coral reefs, scientists have debated how one of the world’s most productive and diverse ecosystems can thrive in the marine equivalent of a desert. It is an enigma how the flux of dissolved organic matter (DOM), the largest resource produced on reefs, is tra

  11. Surviving in a Marine Desert: The Sponge Loop Retains Resources Within Coral Reefs

    NARCIS (Netherlands)

    Goeij, de J.M.; Oevelen, van D.; Vermeij, M.J.A.; Osinga, R.; Middelburg, J.J.; Goeij, de A.F.P.M.; Admiraal, W.

    2013-01-01

    Ever since Darwin’s early descriptions of coral reefs, scientists have debated how one of the world’s most productive and diverse ecosystems can thrive in the marine equivalent of a desert. It is an enigma how the flux of dissolved organic matter (DOM), the largest resource produced on reefs, is tra

  12. Effects of nutrient enrichment on the primary producers of a degraded coral reef

    NARCIS (Netherlands)

    den Haan, J.

    2015-01-01

    Coral reefs are highly diverse and productive ecosystems, teeming with life in often very nutrient-poor waters. However, during the past decades various human activities, including sewage discharge and land runoff augmented by coastal construction, have enriched the waters overlying many reefs aroun

  13. Coral reefs as the first line of defense: Shoreline protection in face of climate change.

    Science.gov (United States)

    Elliff, Carla I; Silva, Iracema R

    2017-03-25

    Coral reefs are responsible for a wide array of ecosystem services including shoreline protection. However, the processes involved in delivering this particular service have not been fully understood. The objective of the present review was to compile the main results in the literature regarding the study of shoreline protection delivered by coral reefs, identifying the main threats climate change imposes to the service, and discuss mitigation and recovery strategies that can and have been applied to these ecosystems. While different zones of a reef have been associated with different levels of wave energy and wave height attenuation, more information is still needed regarding the capacity of different reef morphologies to deliver shoreline protection. Moreover, the synergy between the main threats imposed by climate change to coral reefs has also not been thoroughly investigated. Recovery strategies are being tested and while there are numerous mitigation options, the challenge remains as to how to implement them and monitor their efficacy.

  14. Seascape-scale trophic links for fish on inshore coral reefs

    Science.gov (United States)

    Davis, Jean P.; Pitt, Kylie A.; Fry, Brian; Olds, Andrew D.; Connolly, Rod M.

    2014-12-01

    It is increasingly accepted that coastal habitats such as inshore coral reefs do not function in isolation but rather as part of a larger habitat network. In the Caribbean, trophic subsidies from habitats adjacent to coral reefs support the diet of reef fishes, but it is not known whether similar trophic links occur on reefs in the Indo-Pacific. Here, we test whether reef fishes in inshore coral, mangrove, and seagrass habitats are supported by trophic links. We used carbon stable isotopes and mathematical mixing models to determine the minimum proportion of resources from mangrove or seagrass habitats in the diet of five fish species from coral reefs at varying distances (0-2,200 m) from these habitats in Moreton Bay, Queensland, eastern Australia. Of the fish species that are more abundant on reefs near to mangroves, Lutjanus russelli and Acanthopagrus australis showed no minimum use of diet sources from mangrove habitat. Siganus fuscescens utilized a minimum of 25-44 % mangrove sources and this contribution increased with the proximity of reefs to mangroves ( R 2 = 0.91). Seagrass or reef flat sources contributed a minimum of 14-78 % to the diet of Diagramma labiosum, a species found in higher abundance on reefs near seagrass beds, but variation in diet among reefs was unrelated to seascape structure. Seagrass or reef flat sources also contributed a minimum of 8-55 % to a fish species found only on reefs ( Pseudolabrus guentheri), indicating that detrital subsidies from these habitats may subsidize fish diet on reefs. These results suggest that carbon sources from multiple habitats contribute to the functioning of inshore coral reef ecosystems and that trophic connectivity between reefs and mangroves may enhance production of a functionally important herbivore.

  15. Coral Reefs: An English Compilation of Activities for Middle School Students.

    Science.gov (United States)

    Walker, Sharon H.; Newton, R. Amanda; Ortiz, Alida

    This activity book on coral reefs for middle school students is divided into 10 sections. Section 1 contains the introduction. Section 2 describes what coral reefs are while section 3 describes how coral reefs reproduce and grow. Section 4 discusses where coral reefs are found and section 5 describes life on a coral reef. Section 6 discusses the…

  16. Coral reef habitat response to climate change scenarios.

    Directory of Open Access Journals (Sweden)

    Lauren A Freeman

    Full Text Available Coral reef ecosystems are threatened by both climate change and direct anthropogenic stress. Climate change will alter the physico-chemical environment that reefs currently occupy, leaving only limited regions that are conducive to reef habitation. Identifying these regions early may aid conservation efforts and inform decisions to transplant particular coral species or groups. Here a species distribution model (Maxent is used to describe habitat suitable for coral reef growth. Two climate change scenarios (RCP4.5, RCP8.5 from the National Center for Atmospheric Research's Community Earth System Model were used with Maxent to determine environmental suitability for corals (order Scleractinia. Environmental input variables best at representing the limits of suitable reef growth regions were isolated using a principal component analysis. Climate-driven changes in suitable habitat depend strongly on the unique region of reefs used to train Maxent. Increased global habitat loss was predicted in both climate projections through the 21(st century. A maximum habitat loss of 43% by 2100 was predicted in RCP4.5 and 82% in RCP8.5. When the model is trained solely with environmental data from the Caribbean/Atlantic, 83% of global habitat was lost by 2100 for RCP4.5 and 88% was lost for RCP8.5. Similarly, global runs trained only with Pacific Ocean reefs estimated that 60% of suitable habitat would be lost by 2100 in RCP4.5 and 90% in RCP8.5. When Maxent was trained solely with Indian Ocean reefs, suitable habitat worldwide increased by 38% in RCP4.5 by 2100 and 28% in RCP8.5 by 2050. Global habitat loss by 2100 was just 10% for RCP8.5. This projection suggests that shallow tropical sites in the Indian Ocean basin experience conditions today that are most similar to future projections of worldwide conditions. Indian Ocean reefs may thus be ideal candidate regions from which to select the best strands of coral for potential re-seeding efforts.

  17. Coral reef habitat response to climate change scenarios.

    Science.gov (United States)

    Freeman, Lauren A; Kleypas, Joan A; Miller, Arthur J

    2013-01-01

    Coral reef ecosystems are threatened by both climate change and direct anthropogenic stress. Climate change will alter the physico-chemical environment that reefs currently occupy, leaving only limited regions that are conducive to reef habitation. Identifying these regions early may aid conservation efforts and inform decisions to transplant particular coral species or groups. Here a species distribution model (Maxent) is used to describe habitat suitable for coral reef growth. Two climate change scenarios (RCP4.5, RCP8.5) from the National Center for Atmospheric Research's Community Earth System Model were used with Maxent to determine environmental suitability for corals (order Scleractinia). Environmental input variables best at representing the limits of suitable reef growth regions were isolated using a principal component analysis. Climate-driven changes in suitable habitat depend strongly on the unique region of reefs used to train Maxent. Increased global habitat loss was predicted in both climate projections through the 21(st) century. A maximum habitat loss of 43% by 2100 was predicted in RCP4.5 and 82% in RCP8.5. When the model is trained solely with environmental data from the Caribbean/Atlantic, 83% of global habitat was lost by 2100 for RCP4.5 and 88% was lost for RCP8.5. Similarly, global runs trained only with Pacific Ocean reefs estimated that 60% of suitable habitat would be lost by 2100 in RCP4.5 and 90% in RCP8.5. When Maxent was trained solely with Indian Ocean reefs, suitable habitat worldwide increased by 38% in RCP4.5 by 2100 and 28% in RCP8.5 by 2050. Global habitat loss by 2100 was just 10% for RCP8.5. This projection suggests that shallow tropical sites in the Indian Ocean basin experience conditions today that are most similar to future projections of worldwide conditions. Indian Ocean reefs may thus be ideal candidate regions from which to select the best strands of coral for potential re-seeding efforts.

  18. Coral reefs: threats and conservation in an era of global change.

    Science.gov (United States)

    Riegl, Bernhard; Bruckner, Andy; Coles, Steve L; Renaud, Philip; Dodge, Richard E

    2009-04-01

    Coral reefs are iconic, threatened ecosystems that have been in existence for approximately 500 million years, yet their continued ecological persistence seems doubtful at present. Anthropogenic modification of chemical and physical atmospheric dynamics that cause coral death by bleaching and newly emergent diseases due to increased heat and irradiation, as well as decline in calcification caused by ocean acidification due to increased CO(2), are the most important large-scale threats. On more local scales, overfishing and destructive fisheries, coastal construction, nutrient enrichment, increased runoff and sedimentation, and the introduction of nonindigenous invasive species have caused phase shifts away from corals. Already approximately 20% of the world's reefs are lost and approximately 26% are under imminent threat. Conservation science of coral reefs is well advanced, but its practical application has often been lagging. Societal priorites, economic pressures, and legal/administrative systems of many countries are more prone to destroy rather than conserve coral-reef ecosystems. Nevertheless, many examples of successful conservation exist from the national level to community-enforced local action. When effectively managed, protected areas have contributed to regeneration of coral reefs and stocks of associated marine resources. Local communities often support coral-reef conservation in order to raise income potential associated with tourism and/or improved resource levels. Coral reefs create an annual income in S-Florida alone of over $4 billion. Thus, no conflict between development, societal welfare, and coral-reef conservation needs to exist. Despite growing threats, it is not too late for decisive action to protect and save these economically and ecologically high-value ecosystems. Conservation science plays a critical role in designing effective strategies.

  19. Evidence for multiple stressor interactions and effects on coral reefs.

    Science.gov (United States)

    Ban, Stephen S; Graham, Nicholas A J; Connolly, Sean R

    2014-03-01

    Concern is growing about the potential effects of interacting multiple stressors, especially as the global climate changes. We provide a comprehensive review of multiple stressor interactions in coral reef ecosystems, which are widely considered to be one of the most sensitive ecosystems to global change. First, we synthesized coral reef studies that examined interactions of two or more stressors, highlighting stressor interactions (where one stressor directly influences another) and potentially synergistic effects on response variables (where two stressors interact to produce an effect that is greater than purely additive). For stressor-stressor interactions, we found 176 studies that examined at least 2 of the 13 stressors of interest. Applying network analysis to analyze relationships between stressors, we found that pathogens were exacerbated by more costressors than any other stressor, with ca. 78% of studies reporting an enhancing effect by another stressor. Sedimentation, storms, and water temperature directly affected the largest number of other stressors. Pathogens, nutrients, and crown-of-thorns starfish were the most-influenced stressors. We found 187 studies that examined the effects of two or more stressors on a third dependent variable. The interaction of irradiance and temperature on corals has been the subject of more research (62 studies, 33% of the total) than any other combination of stressors, with many studies reporting a synergistic effect on coral symbiont photosynthetic performance (n = 19). Second, we performed a quantitative meta-analysis of existing literature on this most-studied interaction (irradiance and temperature). We found that the mean effect size of combined treatments was statistically indistinguishable from a purely additive interaction, although it should be noted that the sample size was relatively small (n = 26). Overall, although in aggregate a large body of literature examines stressor effects on coral reefs and coral

  20. Coral diseases and bleaching on Colombian Caribbean coral reefs

    Directory of Open Access Journals (Sweden)

    Raúl Navas-Camacho

    2010-05-01

    Full Text Available Since 1998 the National Monitoring System for the Coral Reefs of Colombia (SIMAC has monitored the occurrence of coral bleaching and diseases in some Colombian coral reefs (permanent stations at San Andres Island, Rosario Islands, Tayrona, San Bernardo Islands and Urabá. The main purpose is to evaluate their health status and to understand the factors that have been contributing to their decline. To estimate these occurrences, annual surveys in 126 permanent belt transects (10x2m with different depth intervals (3-6 meters, 9-12 meters and 15-18 meters are performed at all reef sites. Data from the 1998-2004 period, revealed that San Andrés Island had many colonies with diseases (38.9 colonies/m2, and Urabá had high numbers with bleaching (54.4 colonies/m2. Of the seven reported coral diseases studied, Dark Spots Disease (DSD, and White Plague Disease (WPD were noteworthy because they occurred in all Caribbean monitored sites, and because of their high interannual infection incidence. Thirty five species of scleractinian corals were affected by at least one disease and a high incidence of coral diseases on the main reef builders is documented. Bleaching was present in 34 species. During the whole monitoring period, Agaricia agaricites and Siderastrea siderea were the species most severely affected by DSD and bleaching, respectively. Diseases on species such as Agaricia fragilis, A.grahamae, A. humilis, Diploria clivosa, Eusmilia fastigiata, Millepora complanata, and Mycetophyllia aliciae are recorded for first time in Colombia. We present bleaching and disease incidences, kinds of diseases, coral species affected, reef localities studied, depth intervals of surveys, and temporal (years variation for each geographic area. This variation makes difficult to clearly determine defined patterns or general trends for monitored reefs. This is the first long-term study of coral diseases and bleaching in the Southwestern Caribbean, and one of the few

  1. Operationalizing resilience for adaptive coral reef management under global environmental change.

    Science.gov (United States)

    Anthony, Kenneth R N; Marshall, Paul A; Abdulla, Ameer; Beeden, Roger; Bergh, Chris; Black, Ryan; Eakin, C Mark; Game, Edward T; Gooch, Margaret; Graham, Nicholas A J; Green, Alison; Heron, Scott F; van Hooidonk, Ruben; Knowland, Cheryl; Mangubhai, Sangeeta; Marshall, Nadine; Maynard, Jeffrey A; McGinnity, Peter; McLeod, Elizabeth; Mumby, Peter J; Nyström, Magnus; Obura, David; Oliver, Jamie; Possingham, Hugh P; Pressey, Robert L; Rowlands, Gwilym P; Tamelander, Jerker; Wachenfeld, David; Wear, Stephanie

    2015-01-01

    Cumulative pressures from global climate and ocean change combined with multiple regional and local-scale stressors pose fundamental challenges to coral reef managers worldwide. Understanding how cumulative stressors affect coral reef vulnerability is critical for successful reef conservation now and in the future. In this review, we present the case that strategically managing for increased ecological resilience (capacity for stress resistance and recovery) can reduce coral reef vulnerability (risk of net decline) up to a point. Specifically, we propose an operational framework for identifying effective management levers to enhance resilience and support management decisions that reduce reef vulnerability. Building on a system understanding of biological and ecological processes that drive resilience of coral reefs in different environmental and socio-economic settings, we present an Adaptive Resilience-Based management (ARBM) framework and suggest a set of guidelines for how and where resilience can be enhanced via management interventions. We argue that press-type stressors (pollution, sedimentation, overfishing, ocean warming and acidification) are key threats to coral reef resilience by affecting processes underpinning resistance and recovery, while pulse-type (acute) stressors (e.g. storms, bleaching events, crown-of-thorns starfish outbreaks) increase the demand for resilience. We apply the framework to a set of example problems for Caribbean and Indo-Pacific reefs. A combined strategy of active risk reduction and resilience support is needed, informed by key management objectives, knowledge of reef ecosystem processes and consideration of environmental and social drivers. As climate change and ocean acidification erode the resilience and increase the vulnerability of coral reefs globally, successful adaptive management of coral reefs will become increasingly difficult. Given limited resources, on-the-ground solutions are likely to focus increasingly on

  2. Operationalizing resilience for adaptive coral reef management under global environmental change

    Science.gov (United States)

    Anthony, Kenneth RN; Marshall, Paul A; Abdulla, Ameer; Beeden, Roger; Bergh, Chris; Black, Ryan; Eakin, C Mark; Game, Edward T; Gooch, Margaret; Graham, Nicholas AJ; Green, Alison; Heron, Scott F; van Hooidonk, Ruben; Knowland, Cheryl; Mangubhai, Sangeeta; Marshall, Nadine; Maynard, Jeffrey A; McGinnity, Peter; McLeod, Elizabeth; Mumby, Peter J; Nyström, Magnus; Obura, David; Oliver, Jamie; Possingham, Hugh P; Pressey, Robert L; Rowlands, Gwilym P; Tamelander, Jerker; Wachenfeld, David; Wear, Stephanie

    2015-01-01

    Cumulative pressures from global climate and ocean change combined with multiple regional and local-scale stressors pose fundamental challenges to coral reef managers worldwide. Understanding how cumulative stressors affect coral reef vulnerability is critical for successful reef conservation now and in the future. In this review, we present the case that strategically managing for increased ecological resilience (capacity for stress resistance and recovery) can reduce coral reef vulnerability (risk of net decline) up to a point. Specifically, we propose an operational framework for identifying effective management levers to enhance resilience and support management decisions that reduce reef vulnerability. Building on a system understanding of biological and ecological processes that drive resilience of coral reefs in different environmental and socio-economic settings, we present an Adaptive Resilience-Based management (ARBM) framework and suggest a set of guidelines for how and where resilience can be enhanced via management interventions. We argue that press-type stressors (pollution, sedimentation, overfishing, ocean warming and acidification) are key threats to coral reef resilience by affecting processes underpinning resistance and recovery, while pulse-type (acute) stressors (e.g. storms, bleaching events, crown-of-thorns starfish outbreaks) increase the demand for resilience. We apply the framework to a set of example problems for Caribbean and Indo-Pacific reefs. A combined strategy of active risk reduction and resilience support is needed, informed by key management objectives, knowledge of reef ecosystem processes and consideration of environmental and social drivers. As climate change and ocean acidification erode the resilience and increase the vulnerability of coral reefs globally, successful adaptive management of coral reefs will become increasingly difficult. Given limited resources, on-the-ground solutions are likely to focus increasingly on

  3. A Global Estimate of the Number of Coral Reef Fishers.

    Directory of Open Access Journals (Sweden)

    Louise S L Teh

    Full Text Available Overfishing threatens coral reefs worldwide, yet there is no reliable estimate on the number of reef fishers globally. We address this data gap by quantifying the number of reef fishers on a global scale, using two approaches - the first estimates reef fishers as a proportion of the total number of marine fishers in a country, based on the ratio of reef-related to total marine fish landed values. The second estimates reef fishers as a function of coral reef area, rural coastal population, and fishing pressure. In total, we find that there are 6 million reef fishers in 99 reef countries and territories worldwide, of which at least 25% are reef gleaners. Our estimates are an improvement over most existing fisher population statistics, which tend to omit accounting for gleaners and reef fishers. Our results suggest that slightly over a quarter of the world's small-scale fishers fish on coral reefs, and half of all coral reef fishers are in Southeast Asia. Coral reefs evidently support the socio-economic well-being of numerous coastal communities. By quantifying the number of people who are employed as reef fishers, we provide decision-makers with an important input into planning for sustainable coral reef fisheries at the appropriate scale.

  4. Maintenance of fish diversity on disturbed coral reefs

    Science.gov (United States)

    Wilson, S. K.; Dolman, A. M.; Cheal, A. J.; Emslie, M. J.; Pratchett, M. S.; Sweatman, H. P. A.

    2009-03-01

    Habitat perturbations play a major role in shaping community structure; however, the elements of disturbance-related habitat change that affect diversity are not always apparent. This study examined the effects of habitat disturbances on species richness of coral reef fish assemblages using annual surveys of habitat and 210 fish species from 10 reefs on the Great Barrier Reef (GBR). Over a period of 11 years, major disturbances, including localised outbreaks of crown-of-thorns sea star ( Acanthaster planci), severe storms or coral bleaching, resulted in coral decline of 46-96% in all the 10 reefs. Despite declines in coral cover, structural complexity of the reef framework was retained on five and species richness of coral reef fishes maintained on nine of the disturbed reefs. Extensive loss of coral resulted in localised declines of highly specialised coral-dependent species, but this loss of diversity was more than compensated for by increases in the number of species that feed on the epilithic algal matrix (EAM). A unimodal relationship between areal coral cover and species richness indicated species richness was greatest at approximately 20% coral cover declining by 3-4 species (6-8% of average richness) at higher and lower coral cover. Results revealed that declines in coral cover on reefs may have limited short-term impact on the diversity of coral reef fishes, though there may be fundamental changes in the community structure of fishes.

  5. Differential response of coral communities to Caulerpa spp. bloom in the reefs of Indian Ocean.

    Science.gov (United States)

    Manikandan, B; Ravindran, J

    2017-02-01

    Coral reef ecosystems are disturbed in tandem by climatic and anthropogenic stressors. A number of factors act synergistically to reduce the live coral cover and threaten the existence of reefs. Continuous monitoring of the coral communities during 2012-2014 captured an unprecedented growth of macroalgae as a bloom at Gulf of Mannar (GoM) and Palk Bay (PB) which are protected and unprotected reefs, respectively. The two reefs varying in their protection level enabled to conduct an assessment on the response of coral communities and their recovery potential during and after the macroalgal bloom. Surveys in 2012 revealed a live coral cover of 36.8 and 14.6% in GoM and PB, respectively. Live coral cover was lost at an annual rate of 4% in PB due to the Caulerpa racemosa blooms that occurred in 2013 and 2014. In GoM, the loss of live coral cover was estimated to be 16.5% due to C. taxifolia bloom in 2013. Tissue regeneration by the foliose and branching coral morphotypes aided the recovery of live coral cover in GoM, whereas the chances for the recovery of live coral cover in PB reef were low, primarily due to frequent algal blooms, and the existing live coral cover was mainly due to the abundance of slow-growing massive corals. In combination, results of this study suggested that the recovery of a coral reef after a macroalgal bloom largely depends on coral species composition and the frequency of stress events. A further study linking macroalgal bloom to its specific cause is essential for the successful intervention and management.

  6. Development and implementation of coral reef biocriteria in U.S. jurisdictions.

    Science.gov (United States)

    Bradley, Patricia; Fisher, William S; Bell, Heidi; Davis, Wayne; Chan, Valerie; LoBue, Charles; Wiltse, Wendy

    2009-03-01

    Coral reefs worldwide are declining at an alarming rate and are under continuous threat from both natural and anthropogenic environmental stressors. Warmer sea temperatures attributed to global climate change and numerous human activities at local scales place these valuable ecosystems at risk. Reefs provide numerous services, including shoreline protection, fishing, tourism and biological diversity, which are lost through physical damage, overfishing, and pollution. Pollution can be controlled under provisions of the Clean Water Act, but these options have not been fully employed to protect coral reefs. No U.S. jurisdiction has implemented coral reef biocriteria, which are narrative or quantitative water quality standards based on the condition of a biological resource or assemblage. The President's Ocean Action Plan directs the U.S. Environmental Protection Agency (EPA) to develop biological assessment methods and biological criteria for evaluating and maintaining the health of coral reef ecosystems. EPA has formed the Coral Reef Biocriteria Working Group (CRBWG) to foster development of coral reef biocriteria through focused research, evaluation and communication among Agency partners and U.S. jurisdictions. Ongoing CRBWG activities include development and evaluation of a rapid bioassessment protocol for application in biocriteria programs; development of a survey design and monitoring strategy for the U.S. Virgin Islands; comprehensive reviews of biocriteria approaches proposed by states and territories; and assembly of data from a variety of monitoring programs for additional metrics. Guidance documents are being prepared to assist U.S. jurisdictions in reaching protective and defensible biocriteria.

  7. Changing carbonate chemistry in ocean waters surrounding coral reefs in the CMIP5 ensemble

    Science.gov (United States)

    Ricke, K.; Schneider, K.; Cao, L.; Caldeira, K.

    2012-12-01

    Coral reefs comprise some of the most biodiverse ecosystems in the world. Today they are threatened by a number of stressors, including pollution, bleaching from global warming and ocean acidification. In this study, we focus on the implications of ocean acidification for the open ocean chemistry surrounding coral reefs. We use results from 13 Earth System Models included in the Coupled Model Intercomparison Project 5 (CMIP5) to examine the changing aragonite saturations (Ωa) of open ocean waters surrounding approximately 6,000 coral reefs. These 13 Earth System Models participating in CMIP5 each have interactive ocean biogeochemistry models that output state variables including DIC, alkalinity, SST, and salinity. Variation in these values were combined with values from the GLODAP database to calculate aragonite, the form of calcium carbonate that corals use to make their skeletons. We used reef locations from ReefBase that were within one degree (in latitude or longitude) of water masses represented both in the GLODAP database and in the climate models. Carbonate chemistry calculations were performed by Dr. James C. Orr (IPSL) as part of a separate study. We find that in preindustrial times, 99.9 % of coral reefs were located in regions of the ocean with aragonite saturations of 3.5 or more. The saturation threshold for viable reef ecosystems in uncertain, but the pre-industrial distribution of water chemistry surrounding coral reefs may nevertheless provide some indication of viability. We examine the fate of coral reefs in the context of several potential aragonite saturation thresholds, i.e., when Ωa_crit equals 3, 3.25, or 3.5. We show that under a business-as-usual scenario Representative Concentration Pathway (RCP) 8.5, the specific value of Ωa_crit does not affect the long-term fate of coral reefs -- by the end of the 21st century, no coral reef considered is surrounded by water with Ωa> 3. However, under scenarios with significant CO2 emissions

  8. Regional hard coral distribution within geomorphic and reef flat ecological zones determined by satellite imagery of the Xisha Islands, South China Sea

    Science.gov (United States)

    Zuo, Xiuling; Su, Fenzhen; Zhao, Huanting; Zhang, Junjue; Wang, Qi; Wu, Di

    2017-05-01

    Coral reefs in the Xisha Islands (also known as the Paracel Islands in English), South China Sea, have experienced dramatic declines in coral cover. However, the current regional scale hard coral distribution of geomorphic and ecological zones, essential for reefs management in the context of global warming and ocean acidification, is not well documented. We analyzed data from field surveys, Landsat-8 and GF-1 images to map the distribution of hard coral within geomorphic zones and reef flat ecological zones. In situ surveys conducted in June 2014 on nine reefs provided a complete picture of reef status with regard to live coral diversity, evenness of coral cover and reef health (live versus dead cover) for the Xisha Islands. Mean coral cover was 12.5% in 2014 and damaged reefs seemed to show signs of recovery. Coral cover in sheltered habitats such as lagoon patch reefs and biotic dense zones of reef flats was higher, but there were large regional differences and low diversity. In contrast, the more exposed reef slopes had high coral diversity, along with high and more equal distributions of coral cover. Mean hard coral cover of other zones was reef system was estimated to cover 1 060 km2, and the emergent reefs covered 787 m2. Hard corals of emergent reefs were considered to cover 97 km2. The biotic dense zone of the reef flat was a very common zone on all simple atolls, especially the broader northern reef flats. The total cover of live and dead coral can reach above 70% in this zone, showing an equilibrium between live and dead coral as opposed to coral and algae. This information regarding the spatial distribution of hard coral can support and inform the management of Xisha reef ecosystems.

  9. Are artificial reefs surrogates of natural habitats for corals and fish in Dubai, United Arab Emirates?

    Science.gov (United States)

    Burt, J.; Bartholomew, A.; Usseglio, P.; Bauman, A.; Sale, P. F.

    2009-09-01

    Artificial reefs are often promoted as mitigating human impacts in coastal ecosystems and enhancing fisheries; however, evidence supporting their benefits is equivocal. Such structures must be compared with natural reefs in order to assess their performance, but past comparisons typically examined artificial structures that were too small, or were immature, relative to the natural reefs. We compared coral and fish communities on two large (>400,000 m3) and mature (>25 year) artificial reefs with six natural coral patches. Coral cover was higher on artificial reefs (50%) than in natural habitats (31%), but natural coral patches contained higher species richness (29 vs. 20) and coral diversity ( H' = 2.3 vs. 1.8). Multivariate analyses indicated strong differences between coral communities in natural and artificial habitats. Fish communities were sampled seasonally for 1 year. Multivariate fish communities differed significantly among habitat types in the summer and fall, but converged in the winter and spring. Univariate analysis indicated that species richness and abundance were stable throughout the year on natural coral patches but increased significantly in the summer on artificial reefs compared with the winter and spring, explaining the multivariate changes in community structure. The increased summer abundance on artificial reefs was mainly due to adult immigration. Piscivores were much more abundant in the fall than in the winter or spring on artificial reefs, but had low and stable abundance throughout the year in natural habitats. It is likely that the decreased winter and spring abundance of fish on the artificial reefs resulted from both predation and emigration. These results indicate that large artificial reefs can support diverse and abundant coral and fish communities. However, these communities differ structurally and functionally from those in natural habitats, and they should not be considered as replacements for natural coral and fish communities.

  10. Water Quality Standards for Coral Reef Protection

    Science.gov (United States)

    The U.S. Clean Water Act provides a legal framework to protect coastal biological resources such as coral reefs, mangrove forests, and seagrass meadows from the damaging effects of human activities. Even though many resources are protected under this authority, water quality stan...

  11. Ophiuroidea (Echinodermata) from coral reefs in the Mexican Pacific

    Science.gov (United States)

    Granja–Fernández, Rebeca; Herrero-Pérezrul, María D.; López-Pérez, Ramón A.; Hernández, Luis; Rodríguez-Zaragoza, Fabián A.; Jones, Robert Wallace; Pineda-López, Rubén

    2014-01-01

    Abstract There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of brittle stars belonging to nine genera and seven families. Ophiocnida hispida in Jalisco, Ophiophragmus papillatus in Guerrero, and Ophiothrix (Ophiothrix) spiculata and Ophiactis simplex in Colima are new distribution records. The record of O. papillatus is remarkable because the species has not been reported since its description in 1940. The brittle stars collected in this study, represent 22.2% of the total species previously reported from the Mexican Pacific. Presently, anthropogenic activities on the coral reefs of the Mexican Pacific have increased, thus the biodiversity of brittle stars in these ecosystems may be threatened. PMID:24843284

  12. Ophiuroidea (Echinodermata) from coral reefs in the Mexican Pacific.

    Science.gov (United States)

    Granja-Fernández, Rebeca; Herrero-Pérezrul, María D; López-Pérez, Ramón A; Hernández, Luis; Rodríguez-Zaragoza, Fabián A; Jones, Robert Wallace; Pineda-López, Rubén

    2014-01-01

    There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of brittle stars belonging to nine genera and seven families. Ophiocnida hispida in Jalisco, Ophiophragmus papillatus in Guerrero, and Ophiothrix (Ophiothrix) spiculata and Ophiactis simplex in Colima are new distribution records. The record of O. papillatus is remarkable because the species has not been reported since its description in 1940. The brittle stars collected in this study, represent 22.2% of the total species previously reported from the Mexican Pacific. Presently, anthropogenic activities on the coral reefs of the Mexican Pacific have increased, thus the biodiversity of brittle stars in these ecosystems may be threatened.

  13. Ophiuroidea (Echinodermata from coral reefs in the Mexican Pacific

    Directory of Open Access Journals (Sweden)

    Rebeca Granja Fernández

    2014-05-01

    Full Text Available There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of brittle stars belonging to nine genera and seven families. Ophiocnida hispida in Jalisco, Ophiophragmus papillatus in Guerrero, and Ophiothrix (Ophiothrix spiculata and Ophiactis simplex in Colima are new distribution records. The record of O. papillatus is remarkable because the species has not been reported since its description in 1940. The brittle stars collected in this study, represent 22.2% of the total species previously reported from the Mexican Pacific. Presently, anthropogenic activities on the coral reefs of the Mexican Pacific have increased, thus the biodiversity of brittle stars in these ecosystems may be threatened.

  14. The Microbial Signature Provides Insight into the Mechanistic Basis of Coral Success across Reef Habitats

    Science.gov (United States)

    Leggat, William; Bongaerts, Pim

    2016-01-01

    ABSTRACT For ecosystems vulnerable to environmental change, understanding the spatiotemporal stability of functionally crucial symbioses is fundamental to determining the mechanisms by which these ecosystems may persist. The coral Pachyseris speciosa is a successful environmental generalist that succeeds in diverse reef habitats. The generalist nature of this coral suggests it may have the capacity to form functionally significant microbial partnerships to facilitate access to a range of nutritional sources within different habitats. Here, we propose that coral is a metaorganism hosting three functionally distinct microbial interactions: a ubiquitous core microbiome of very few symbiotic host-selected bacteria, a microbiome of spatially and/or regionally explicit core microbes filling functional niches (100,000 phylotypes). We find that this coral hosts upwards of 170,000 distinct phylotypes and provide evidence for the persistence of a select group of bacteria in corals across environmental habitats of the Great Barrier Reef and Coral Sea. We further show that a higher number of bacteria are consistently associated with corals on mesophotic reefs than on shallow reefs. An increase in microbial diversity with depth suggests reliance by this coral on bacteria for nutrient acquisition on reefs exposed to nutrient upwelling. Understanding the complex microbial communities of host organisms across broad biotic and abiotic environments as functionally distinct microbiomes can provide insight into those interactions that are ubiquitous niche symbioses and those that provide competitive advantage within the hosts’ environment. PMID:27460792

  15. The Microbial Signature Provides Insight into the Mechanistic Basis of Coral Success across Reef Habitats

    Directory of Open Access Journals (Sweden)

    Alejandra Hernandez-Agreda

    2016-07-01

    Full Text Available For ecosystems vulnerable to environmental change, understanding the spatiotemporal stability of functionally crucial symbioses is fundamental to determining the mechanisms by which these ecosystems may persist. The coral Pachyseris speciosa is a successful environmental generalist that succeeds in diverse reef habitats. The generalist nature of this coral suggests it may have the capacity to form functionally significant microbial partnerships to facilitate access to a range of nutritional sources within different habitats. Here, we propose that coral is a metaorganism hosting three functionally distinct microbial interactions: a ubiquitous core microbiome of very few symbiotic host-selected bacteria, a microbiome of spatially and/or regionally explicit core microbes filling functional niches (100,000 phylotypes. We find that this coral hosts upwards of 170,000 distinct phylotypes and provide evidence for the persistence of a select group of bacteria in corals across environmental habitats of the Great Barrier Reef and Coral Sea. We further show that a higher number of bacteria are consistently associated with corals on mesophotic reefs than on shallow reefs. An increase in microbial diversity with depth suggests reliance by this coral on bacteria for nutrient acquisition on reefs exposed to nutrient upwelling. Understanding the complex microbial communities of host organisms across broad biotic and abiotic environments as functionally distinct microbiomes can provide insight into those interactions that are ubiquitous niche symbioses and those that provide competitive advantage within the hosts’ environment.

  16. Ingestion of Microplastics and Their Impact on Calcification in Reef-Building Corals

    Science.gov (United States)

    Zink, C. P.; Smith, R. T.

    2016-02-01

    Since the early 1970's, researchers began identifying plastics and other sources of litter as harmful to ecosystems. In recent years, there's been a growing concern about microscopic plastic debris (microplastics) and its impact on marine organisms. Likewise, microplastics are currently and continuously being documented from environmental samples on a global scale. The ecosystems most likely affected by their presence are shallow marine habitats, such as near-shore coral reefs. One concern is that microplastics may be ingested by reef-building corals and negatively impact their physiology. In this study, two species of Caribbean reef-building corals, Orbicella faveolata and Porites porites were investigated for rates of ingesting microplastics. Coral samples were incubated with 100μm micro-beads manufactured with a fluorescent label to aid in recovery and quantification from the coral tissue. Following the consumption of plastic, we measured instantaneous rates of calcification as a proxy for physiological performance compared to controls. Our results indicate that corals ingest microplastic particles and maintain them internally for at least 24 hours. Our initial findings suggest that the ingestion of ≥ 3 microplastic particles cm-2 may negatively impact rates of coral calcification. In light of these preliminary findings, further investigations should examine the long-term effect of environmentally relevant concentrations of microplastics on reef corals and its potential detriment to reef building capacity.

  17. From Citizen Science to Policy Development on the Coral Reefs of Jamaica

    Directory of Open Access Journals (Sweden)

    M. James C. Crabbe

    2012-01-01

    Full Text Available This paper explores the application of citizen science to help generation of scientific data and capacity-building, and so underpin scientific ideas and policy development in the area of coral reef management, on the coral reefs of Jamaica. From 2000 to 2008, ninety Earthwatch volunteers were trained in coral reef data acquisition and analysis and made over 6,000 measurements on fringing reef sites along the north coast of Jamaica. Their work showed that while recruitment of small corals is returning after the major bleaching event of 2005, larger corals are not necessarily so resilient and so need careful management if the reefs are to survive such major extreme events. These findings were used in the development of an action plan for Jamaican coral reefs, presented to the Jamaican National Environmental Protection Agency. It was agreed that a number of themes and tactics need to be implemented in order to facilitate coral reef conservation in the Caribbean. The use of volunteers and citizen scientists from both developed and developing countries can help in forging links which can assist in data collection and analysis and, ultimately, in ecosystem management and policy development.

  18. Pacific Reef Assessment and Monitoring Program Rapid Ecological Assessment Quadrat Surveys of Corals around the Marianas Islands from 2003 to 2007

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Pacific Reef Assessment and Monitoring Program (Pacific RAMP), established by the Coral Reef Ecosystem Program (CREP) of the NOAA Pacific Islands Fisheries...

  19. Scleractinian settlement patterns to natural cleared reef substrata and artificial settlement panels on an Indonesian coral reef

    Science.gov (United States)

    Salinas-de-León, Pelayo; Costales-Carrera, Alba; Zeljkovic, Stephen; Smith, David J.; Bell, James J.

    2011-05-01

    Recruitment is a key factor driving the population dynamics of scleractinian corals, but despite its importance, we still have a poor understanding of recruitment processes in the Coral triangle region, which contains the most biodiverse marine ecosystems in the world. This study aimed to compare settlement rates to artificial settlement panels with cleared areas of natural reef in order to assess whether panels are a suitable indicator of natural coral settlement rates. We recorded coral settlement rates to panels made of two different materials (concrete and terracotta), attached to the reef at two different orientations (vertical and horizontal), and compared these settlement rates to those on cleared areas of natural reef positioned on vertical reef walls, over a 12 month period. We examined settlement rates at four sites in the Wakatobi National Marine Park, south-east Sulawesi, Indonesia; two reefs were light-limited, highly sedimented sites with low coral cover (terracotta panels yield similar settlement rates, and orientation makes no difference to settlement rates when panels are directly attached to the reef. Our results demonstrate that artificial substrata provide comparable settlement rate data to natural substrata and therefore are suitable for monitoring coral settlement rates in the future.

  20. Spatial and seasonal reef calcification in corals and calcareous crusts in the central Red Sea

    Science.gov (United States)

    Roik, Anna; Roder, Cornelia; Röthig, Till; Voolstra, Christian R.

    2016-06-01

    The existence of coral reef ecosystems critically relies on the reef carbonate framework produced by scleractinian corals and calcareous crusts (i.e., crustose coralline algae). While the Red Sea harbors one of the longest connected reef systems in the world, detailed calcification data are only available from the northernmost part. To fill this knowledge gap, we measured in situ calcification rates of primary and secondary reef builders in the central Red Sea. We collected data on the major habitat-forming coral genera Porites, Acropora, and Pocillopora and also on calcareous crusts (CC) in a spatio-seasonal framework. The scope of the study comprised sheltered and exposed sites of three reefs along a cross-shelf gradient and over four seasons of the year. Calcification of all coral genera was consistent across the shelf and highest in spring. In addition, Pocillopora showed increased calcification at exposed reef sites. In contrast, CC calcification increased from nearshore, sheltered to offshore, exposed reef sites, but also varied over seasons. Comparing our data to other reef locations, calcification in the Red Sea was in the range of data collected from reefs in the Caribbean and Indo-Pacific; however, Acropora calcification estimates were at the lower end of worldwide rates. Our study shows that the increasing coral cover from nearshore to offshore environments aligned with CC calcification but not coral calcification, highlighting the potentially important role of CC in structuring reef cover and habitats. While coral calcification maxima have been typically observed during summer in many reef locations worldwide, calcification maxima during spring in the central Red Sea indicate that summer temperatures exceed the optima of reef calcifiers in this region. This study provides a foundation for comparative efforts and sets a baseline to quantify impact of future environmental change in the central Red Sea.

  1. Spatial and seasonal reef calcification in corals and calcareous crusts in the central Red Sea

    KAUST Repository

    Roik, Anna Krystyna

    2015-12-14

    The existence of coral reef ecosystems critically relies on the reef carbonate framework produced by scleractinian corals and calcareous crusts (i.e., crustose coralline algae). While the Red Sea harbors one of the longest connected reef systems in the world, detailed calcification data are only available from the northernmost part. To fill this knowledge gap, we measured in situ calcification rates of primary and secondary reef builders in the central Red Sea. We collected data on the major habitat-forming coral genera Porites, Acropora, and Pocillopora and also on calcareous crusts (CC) in a spatio-seasonal framework. The scope of the study comprised sheltered and exposed sites of three reefs along a cross-shelf gradient and over four seasons of the year. Calcification of all coral genera was consistent across the shelf and highest in spring. In addition, Pocillopora showed increased calcification at exposed reef sites. In contrast, CC calcification increased from nearshore, sheltered to offshore, exposed reef sites, but also varied over seasons. Comparing our data to other reef locations, calcification in the Red Sea was in the range of data collected from reefs in the Caribbean and Indo-Pacific; however, Acropora calcification estimates were at the lower end of worldwide rates. Our study shows that the increasing coral cover from nearshore to offshore environments aligned with CC calcification but not coral calcification, highlighting the potentially important role of CC in structuring reef cover and habitats. While coral calcification maxima have been typically observed during summer in many reef locations worldwide, calcification maxima during spring in the central Red Sea indicate that summer temperatures exceed the optima of reef calcifiers in this region. This study provides a foundation for comparative efforts and sets a baseline to quantify impact of future environmental change in the central Red Sea.

  2. Small cryptopredators contribute to high predation rates on coral reefs

    Science.gov (United States)

    Goatley, Christopher H. R.; González-Cabello, Alonso; Bellwood, David R.

    2017-03-01

    Small fishes suffer high mortality rates on coral reefs, primarily due to predation. Although studies have identified the predators of early post-settlement fishes, the predators of small cryptobenthic fishes remain largely unknown. We therefore used a series of mesocosm experiments with natural habitat and cryptobenthic fish communities to identify the impacts of a range of small potential predators, including several invertebrates, on prey fish populations. While there was high variability in predation rates, many members of the cryptobenthic fish community act as facultative cryptopredators, being prey when small and piscivores when larger. Surprisingly, we also found that smashing mantis shrimps may be important fish predators. Our results highlight the diversity of the predatory community on coral reefs and identify previously unknown trophic links in these complex ecosystems.

  3. Linking Ecological and Perceptual Assessments for Environmental Management: a Coral Reef Case Study

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Dinsdale

    2009-12-01

    Full Text Available Integrating information from a range of community members in environmental management provides a more complete assessment of the problem and a diversification of management options, but is difficult to achieve. To investigate the relationship between different environmental interpretations, I compared three distinct measures of anchor damage on coral reefs: ecological measures, perceptual meanings, and subjective health judgments. The ecological measures identified an increase in the number of overturned corals and a reduction in coral cover, the perceptual meanings identified a loss of visual quality, and the health judgments identified a reduction in the health of the coral reef sites associated with high levels of anchoring. Combining the perceptual meanings and health judgments identified that the judgment of environmental health was a key feature that both scientific and lay participants used to describe the environment. Some participants in the survey were familiar with the coral reef environment, and others were not. However, they provided consistent judgment of a healthy coral reef, suggesting that these judgments were not linked to present-day experiences. By combining subjective judgments and ecological measures, the point at which the environment is deemed to lose visual quality was identified; for these coral reefs, if the level of damage rose above 10.3% and the cover of branching corals dropped below 17.1%, the reefs were described as unhealthy. Therefore, by combining the information, a management agency can involve the community in identifying when remedial action is required or when management policies are effectively maintaining a healthy ecosystem.

  4. Surviving in a marine desert: the sponge loop retains resources within coral reefs.

    Science.gov (United States)

    de Goeij, Jasper M; van Oevelen, Dick; Vermeij, Mark J A; Osinga, Ronald; Middelburg, Jack J; de Goeij, Anton F P M; Admiraal, Wim

    2013-10-04

    Ever since Darwin's early descriptions of coral reefs, scientists have debated how one of the world's most productive and diverse ecosystems can thrive in the marine equivalent of a desert. It is an enigma how the flux of dissolved organic matter (DOM), the largest resource produced on reefs, is transferred to higher trophic levels. Here we show that sponges make DOM available to fauna by rapidly expelling filter cells as detritus that is subsequently consumed by reef fauna. This "sponge loop" was confirmed in aquarium and in situ food web experiments, using (13)C- and (15)N-enriched DOM. The DOM-sponge-fauna pathway explains why biological hot spots such as coral reefs persist in oligotrophic seas--the reef's paradox--and has implications for reef ecosystem functioning and conservation strategies.

  5. The threat to coral reefs from more intense cyclones under climate change.

    Science.gov (United States)

    Cheal, Alistair J; MacNeil, M Aaron; Emslie, Michael J; Sweatman, Hugh

    2017-04-01

    Ocean warming under climate change threatens coral reefs directly, through fatal heat stress to corals and indirectly, by boosting the energy of cyclones that cause coral destruction and loss of associated organisms. Although cyclone frequency is unlikely to rise, cyclone intensity is predicted to increase globally, causing more frequent occurrences of the most destructive cyclones with potentially severe consequences for coral reef ecosystems. While increasing heat stress is considered a pervasive risk to coral reefs, quantitative estimates of threats from cyclone intensification are lacking due to limited data on cyclone impacts to inform projections. Here, using extensive data from Australia's Great Barrier Reef (GBR), we show that increases in cyclone intensity predicted for this century are sufficient to greatly accelerate coral reef degradation. Coral losses on the outer GBR were small, localized and offset by gains on undisturbed reefs for more than a decade, despite numerous cyclones and periods of record heat stress, until three unusually intense cyclones over 5 years drove coral cover to record lows over >1500 km. Ecological damage was particularly severe in the central-southern region where 68% of coral cover was destroyed over >1000 km, forcing record declines in the species richness and abundance of associated fish communities, with many local extirpations. Four years later, recovery of average coral cover was relatively slow and there were further declines in fish species richness and abundance. Slow recovery of community diversity appears likely from such a degraded starting point. Highly unusual characteristics of two of the cyclones, aside from high intensity, inflated the extent of severe ecological damage that would more typically have occurred over 100s of km. Modelling published predictions of future cyclone activity, the likelihood of more intense cyclones within time frames of coral recovery by mid-century poses a global threat to coral

  6. Size structuring and allometric scaling relationships in coral reef fishes.

    Science.gov (United States)

    Dunic, Jillian C; Baum, Julia K

    2017-05-01

    Temperate marine fish communities are often size-structured, with predators consuming increasingly larger prey and feeding at higher trophic levels as they grow. Gape limitation and ontogenetic diet shifts are key mechanisms by which size structuring arises in these communities. Little is known, however, about size structuring in coral reef fishes. Here, we aimed to advance understanding of size structuring in coral reef food webs by examining the evidence for these mechanisms in two groups of reef predators. Given the diversity of feeding modes amongst coral reef fishes, we also compared gape size-body size allometric relationships across functional groups to determine whether they are reliable indicators of size structuring. We used gut content analysis and quantile regressions of predator size-prey size relationships to test for evidence of gape limitation and ontogenetic niche shifts in reef piscivores (n = 13 species) and benthic invertivores (n = 3 species). We then estimated gape size-body size allometric scaling coefficients for 21 different species from four functional groups, including herbivores/detritivores, which are not expected to be gape-limited. We found evidence of both mechanisms for size structuring in coral reef piscivores, with maximum prey size scaling positively with predator body size, and ontogenetic diet shifts including prey type and expansion of prey size. There was, however, little evidence of size structuring in benthic invertivores. Across species and functional groups, absolute and relative gape sizes were largest in piscivores as expected, but gape size-body size scaling relationships were not indicative of size structuring. Instead, relative gape sizes and mouth morphologies may be better indicators. Our results provide evidence that coral reef piscivores are size-structured and that gape limitation and ontogenetic niche shifts are the mechanisms from which this structure arises. Although gape allometry was not indicative of

  7. An observational heat budget analysis of a coral reef, Heron Reef, Great Barrier Reef, Australia

    Science.gov (United States)

    MacKellar, Mellissa C.; McGowan, Hamish A.; Phinn, Stuart R.

    2013-03-01

    Measurements of the surface energy balance, the structure and evolution of the convective atmospheric reef layer (CARL), and local meteorology and hydrodynamics were made during June 2009 and February 2010 at Heron Reef, Australia, to establish the relative partitioning of heating within the water and atmosphere. Horizontal advection was shown to moderate temperature in the CARL and the water, having a cooling influence on the atmosphere, and providing an additional source or sink of energy to the water overlying the reef, depending on tide. The key driver of atmospheric heating was surface sensible heat flux, while heating of the reef water was primarily due to solar radiation, and thermal conduction and convection from the reef substrate. Heating and cooling processes were more defined during winter due to higher sensible and latent heat fluxes and strong diurnal evolution of the CARL. Sudden increases in water temperature were associated with inundation of warmer oceanic water during the flood tide, particularly in winter due to enhanced nocturnal cooling of water overlying the reef. Similarly, cooling of the water over the reef occurred during the ebb tide as heat was transported off the reef to the surrounding ocean. While these results are the first to shed light on the heat budget of a coral reef and overlying CARL, longer-term, systematic measurements of reef thermal budgets are needed under a range of meteorological and hydrodynamic conditions, and across various reef types to elucidate the influence on larger-scale oceanic and atmospheric processes. This is essential for understanding the role of coral reefs in tropical and sub-tropical meteorology; the physical processes that take place during coral bleaching events, and coral and algal community dynamics on coral reefs.

  8. Long-term Shifts in Coral Communities On Shallow to Deep Reef Slopes of Curaçao and Bonaire: Are There Any Winners?

    NARCIS (Netherlands)

    de Bakker, D.M.; Meesters, E.H.; Bak, R.P.M.; Nieuwland, G.; van Duyl, F.C.

    2016-01-01

    Tropical coral reefs are among the most biologically diverse and economically important ecosystems on earth. Nevertheless, we found dramatic changes in coral communities on the reef slopes of Curaçao and Bonaire since 1973. Cover and abundance declined for virtually all coral species. The data show

  9. Long-term Shifts in Coral Communities On Shallow to Deep Reef Slopes of Curaçao and Bonaire: Are There Any Winners?

    NARCIS (Netherlands)

    de Bakker, D.M.; Meesters, E.H.; Bak, R.P.M.; Nieuwland, G.; van Duyl, F.C.

    2016-01-01

    Tropical coral reefs are among the most biologically diverse and economically important ecosystems on earth. Nevertheless, we found dramatic changes in coral communities on the reef slopes of Curaçao and Bonaire since 1973. Cover and abundance declined for virtually all coral species. The data show

  10. Mapping Coral Reef Resilience Indicators Using Field and Remotely Sensed Data

    Directory of Open Access Journals (Sweden)

    Stuart Phinn

    2013-03-01

    Full Text Available In the face of increasing climate-related impacts on coral reefs, the integration of ecosystem resilience into marine conservation planning has become a priority. One strategy, including resilient areas in marine protected area (MPA networks, relies on information on the spatial distribution of resilience. We assess the ability to model and map six indicators of coral reef resilience—stress-tolerant coral taxa, coral generic diversity, fish herbivore biomass, fish herbivore functional group richness, density of juvenile corals and the cover of live coral and crustose coralline algae. We use high spatial resolution satellite data to derive environmental predictors and use these in random forest models, with field observations, to predict resilience indicator values at unsampled locations. Predictions are compared with those obtained from universal kriging and from a baseline model. Prediction errors are estimated using cross-validation, and the ability to map each resilience indicator is quantified as the percentage reduction in prediction error compared to the baseline model. Results are most promising (percentage reduction = 18.3% for mapping the cover of live coral and crustose coralline algae and least promising (percentage reduction = 0% for coral diversity. Our study has demonstrated one approach to map indicators of coral reef resilience. In the context of MPA network planning, the potential to consider reef resilience in addition to habitat and feature representation in decision-support software now exists, allowing planners to integrate aspects of reef resilience in MPA network development.

  11. Optimising Land-Sea Management for Inshore Coral Reefs

    Science.gov (United States)

    Gilby, Ben L.; Olds, Andrew D.; Connolly, Rod M.; Stevens, Tim; Henderson, Christopher J.; Maxwell, Paul S.; Tibbetts, Ian R.; Schoeman, David S.; Rissik, David; Schlacher, Thomas A.

    2016-01-01

    Management authorities seldom have the capacity to comprehensively address the full suite of anthropogenic stressors, particularly in the coastal zone where numerous threats can act simultaneously to impact reefs and other ecosystems. This situation requires tools to prioritise management interventions that result in optimum ecological outcomes under a set of constraints. Here we develop one such tool, introducing a Bayesian Belief Network to model the ecological condition of inshore coral reefs in Moreton Bay (Australia) under a range of management actions. Empirical field data was used to model a suite of possible ecological responses of coral reef assemblages to five key management actions both in the sea (e.g. expansion of reserves, mangrove & seagrass restoration, fishing restrictions) and on land (e.g. lower inputs of sediment and sewage from treatment plants). Models show that expanding marine reserves (a ‘marine action’) and reducing sediment inputs from the catchments (a ‘land action’) were the most effective investments to achieve a better status of reefs in the Bay, with both having been included in >58% of scenarios with positive outcomes, and >98% of the most effective (5th percentile) scenarios. Heightened fishing restrictions, restoring habitats, and reducing nutrient discharges from wastewater treatment plants have additional, albeit smaller effects. There was no evidence that combining individual management actions would consistently produce sizeable synergistic until after maximum investment on both marine reserves (i.e. increasing reserve extent from 31 to 62% of reefs) and sediments (i.e. rehabilitating 6350 km of waterways within catchments to reduce sediment loads by 50%) were implemented. The method presented here provides a useful tool to prioritize environmental actions in situations where multiple competing management interventions exist for coral reefs and in other systems subjected to multiple stressor from the land and the sea

  12. Underwater temperature on off-shore coral reefs of the Florida Keys, U.S.A.

    Science.gov (United States)

    Kuffner, Ilsa B.

    2017-01-01

    The USGS Coral Reef Ecosystems Studies project (http://coastal.er.usgs.gov/crest/) provides science that helps resource managers tasked with the stewardship of coral reef resources. Coral reef organisms are very sensitive to high and low water-temperature extremes. It is critical to precisely know water temperatures experienced by corals and associated plants and animals that live in the dynamic, nearshore environment to document thresholds in temperature tolerance. Here we provide underwater temperature data recorded every fifteen minutes since 2009 at five off-shore coral reefs in the Florida Keys. From northeast to southwest, these sites are Fowey Rocks (Biscayne National Park), Molasses Reef (Florida Keys National Marine Sanctuary, FKNMS), Crocker Reef (FKNMS), Sombrero Reef (FKNMS), and Pulaski Shoal (Dry Tortugas National Park). Temperatures were recorded with Onset® HOBO® Water Temp Pro V2 (U22-001) data loggers in duplicate at each site. Loggers were attached to concrete blocks fixed to the reef with stainless-steel rods and epoxy at depths of 13 to 16 feet of seawater. A portion of the dataset included here was interpreted in conjunction with coral and algal calcification rates in Kuffner et al. (2013).Kuffner, I.B., Hickey, T.D., and Morrison J.M., 2013, Calcification rates of the massive coral Siderastrea siderea and crustose coralline algae along the Florida Keys (USA) outer-reef tract. Coral Reefs 32:987-997. https://doi.org/10.1007/s00338-013-1047-8Note: This data release was versioned on February 01, 2017. Please see the Suggested Citation section for details.

  13. Flattening of Caribbean coral reefs: region-wide declines in architectural complexity.

    Science.gov (United States)

    Alvarez-Filip, Lorenzo; Dulvy, Nicholas K; Gill, Jennifer A; Côté, Isabelle M; Watkinson, Andrew R

    2009-08-22

    Coral reefs are rich in biodiversity, in large part because their highly complex architecture provides shelter and resources for a wide range of organisms. Recent rapid declines in hard coral cover have occurred across the Caribbean region, but the concomitant consequences for reef architecture have not been quantified on a large scale to date. We provide, to our knowledge, the first region-wide analysis of changes in reef architectural complexity, using nearly 500 surveys across 200 reefs, between 1969 and 2008. The architectural complexity of Caribbean reefs has declined nonlinearly with the near disappearance of the most complex reefs over the last 40 years. The flattening of Caribbean reefs was apparent by the early 1980s, followed by a period of stasis between 1985 and 1998 and then a resumption of the decline in complexity to the present. Rates of loss are similar on shallow (20 m) reefs and are consistent across all five subregions. The temporal pattern of declining architecture coincides with key events in recent Caribbean ecological history: the loss of structurally complex Acropora corals, the mass mortality of the grazing urchin Diadema antillarum and the 1998 El Nino Southern Oscillation-induced worldwide coral bleaching event. The consistently low estimates of current architectural complexity suggest regional-scale degradation and homogenization of reef structure. The widespread loss of architectural complexity is likely to have serious consequences for reef biodiversity, ecosystem functioning and associated environmental services.

  14. Influence of Coral Bleaching on the Fauna of Tutia Reef, Tanzania

    OpenAIRE

    Öhman, M.C.; Lindahl, U.; Schelten, C.K.

    1999-01-01

    In 1998, coral reefs of Tanzania were severely affected by bleaching. The coral mortality that followed caused a concern for coral reef degradation and overall resource depletion. In this study, we investigated coral bleaching effects on the coral reef fauna at Tutia Reef in Mafia Island Marine Park, Tanzania. Corals from adjacent reef patches of the species Acropora formosa were transplanted into plots, and reef structure and associated fish assemblages were examined before and after the ble...

  15. The structure and composition of Holocene coral reefs in the Middle Florida Keys

    Science.gov (United States)

    Toth, Lauren T.; Stathakopoulos, Anastasios; Kuffner, Ilsa B.

    2016-07-21

    The Florida Keys reef tract (FKRT) is the largest coral-reef ecosystem in the continental United States. The modern FKRT extends for 362 kilometers along the coast of South Florida from Dry Tortugas National Park in the southwest, through the Florida Keys National Marine Sanctuary (FKNMS), to Fowey Rocks reef in Biscayne National Park in the northeast. Most reefs along the FKRT are sheltered by the exposed islands of the Florida Keys; however, large channels are located between the islands of the Middle Keys. These openings allow for tidal transport of water from Florida Bay onto reefs in the area. The characteristics of the water masses coming from Florida Bay, which can experience broad swings in temperature, salinity, nutrients, and turbidity over short periods of time, are generally unfavorable or “inimical” to coral growth and reef development.Although reef habitats are ubiquitous throughout most of the Upper and Lower Keys, relatively few modern reefs exist in the Middle Keys most likely because of the impacts of inimical waters from Florida Bay. The reefs that are present in the Middle Keys generally are poorly developed compared with reefs elsewhere in the region. For example, Acropora palmata has been the dominant coral on shallow-water reefs in the Caribbean over the last 1.5 million years until populations of the coral declined throughout the region in recent decades. Although A. palmata was historically abundant in the Florida Keys, it was conspicuously absent from reefs in the Middle Keys. Instead, contemporary reefs in the Middle Keys have been dominated by occasional massive (that is, boulder or head) corals and, more often, small, non-reef-building corals.Holocene reef cores have been collected from many locations along the FKRT; however, despite the potential importance of the history of reefs in the Middle Florida Keys to our understanding of the environmental controls on reef development throughout the FKRT, there are currently no published

  16. Congruent patterns of connectivity can inform management for broadcast spawning corals on the Great Barrier Reef.

    Science.gov (United States)

    Lukoschek, Vimoksalehi; Riginos, Cynthia; van Oppen, Madeleine J H

    2016-07-01

    Connectivity underpins the persistence and recovery of marine ecosystems. The Great Barrier Reef (GBR) is the world's largest coral reef ecosystem and managed by an extensive network of no-take zones; however, information about connectivity was not available to optimize the network's configuration. We use multivariate analyses, Bayesian clustering algorithms and assignment tests of the largest population genetic data set for any organism on the GBR to date (Acropora tenuis, >2500 colonies; >50 reefs, genotyped for ten microsatellite loci) to demonstrate highly congruent patterns of connectivity between this common broadcast spawning reef-building coral and its congener Acropora millepora (~950 colonies; 20 reefs, genotyped for 12 microsatellite loci). For both species, there is a genetic divide at around 19°S latitude, most probably reflecting allopatric differentiation during the Pleistocene. GBR reefs north of 19°S are essentially panmictic whereas southern reefs are genetically distinct with higher levels of genetic diversity and population structure, most notably genetic subdivision between inshore and offshore reefs south of 19°S. These broadly congruent patterns of higher genetic diversities found on southern GBR reefs most likely represent the accumulation of alleles via the southward flowing East Australia Current. In addition, signatures of genetic admixture between the Coral Sea and outer-shelf reefs in the northern, central and southern GBR provide evidence of recent gene flow. Our connectivity results are consistent with predictions from recently published larval dispersal models for broadcast spawning corals on the GBR, thereby providing robust connectivity information about the dominant reef-building genus Acropora for coral reef managers.

  17. A Comparative Analysis of Designed Artificial Reefs as Ecosystem Service Providers: Building Social-Ecological Resilience on Atoll Islands

    OpenAIRE

    Schut, Kaj T.

    2013-01-01

    Coral reef ecosystems are under increasing threat from climatic and anthropogenic pressures. Research has revealed that approximately twenty per cent of the world’s coral reefs have already been degraded and it has been predicted that an additional twenty per cent will be lost if no action is taken. This is particularly problematic for the inhabitants of atoll islands who depend greatly on the goods and services provided by coral reefs. This study suggests that the resilience of social and ec...

  18. A Biophysical Model for Hawaiian Coral Reefs: Coupling Local Ecology, Larval Transport and Climate Change

    Science.gov (United States)

    Kapur, M. R.

    2016-02-01

    Simulative models of reef ecosystems have been used to evaluate ecological responses to a myriad of disturbance events, including fishing pressure, coral bleaching, invasion by alien species, and nutrient loading. The Coral Reef Scenario Evaluation Tool (CORSET), has been developed and instantiated for both the Meso-American Reef (MAR) and South China Sea (SCS) regions. This model is novel in that it accounts for the many scales at which reef ecosystem processes take place; is comprised of a "bottom-up" structure wherein complex behaviors are not pre-programmed, but emergent and highly portable to new systems. Local-scale dynamics are coupled across regions through larval connectivity matrices, derived sophisticated particle transport simulations that include key elements of larval behavior. By this approach, we are able to directly evaluate some of the potential consequences of larval connectivity patterns across a range of spatial scales and under multiple climate scenarios. This work develops and applies the CORSET (Coral Reef Scenario Evaluation Tool) to the Main Hawaiian Islands under a suite of climate and ecological scenarios. We introduce an adaptation constant into reef-building coral dynamics to simulate observed resiliencies to bleaching events. This presentation will share results from the model's instantiation under two Resource Concentration Pathway climate scenarios, with emphasis upon larval connectivity dynamics, emergent coral tolerance to increasing thermal anomalies, and patterns of spatial fishing closures. Results suggest that under a business-as-usual scenario, thermal tolerance and herbivore removal will have synergistic effects on reef resilience.

  19. Coral reef destruction of Small island in 44 years and destructive fishing in Spermonde Archipelago, Indonesia

    Science.gov (United States)

    Nurdin, Nurjannah; Komatsu, Teruhisa; Rani, Chair; Supriadi; Fakhriyyah, Sitti; Agus

    2016-11-01

    Coral reefs are among the most diverse and threatened ecosystems on the planet. The most commonly stated for developing coral reef remote sensing techniques is to asses and or to monitor the status of these ecosystems. The study site was selected one of small island in inner zone Spermonde archipelago, Indonesia. We used Landsat MSS, Landsat TM, Landsat ETM, and Landsat OLI data to examine changes in the coral reefs of inner zone island in the Spermonde Archipelago from 1972 to 2016. The image processing are gap fills, atmospheric correction, geometric corrections, image composites, water column corrections, unsupervised classifications, and reclassification. Some of component change detection procedure was applied to define change. The results showed significant changes in 44 years. Disturbed coral reefs are typically characterized by loss of coral cover by increase in the abundance of dead corals and rubble. Local factors such as destructive fishing is direct destruction of inner zone island. While the impact of local threats may be reduced through management action, global threats to coral reefs are likely to increase in severity in the coming years.

  20. Ecological characteristics of coral patch reefs at Midway Atoll, Northwestern Hawaiian Islands

    Science.gov (United States)

    Schroeder, R.E.; Parrish, J.D.

    2006-01-01

    Ecological aspects of coral patch reefs were studied from 1981 to 1985 in Welles Harbor, Midway Atoll. Water temperatures varied from 17??C in February to 28??C in August. Sizes of reefs studied were described by mean area (59 m2), mean volume (52 m3), vertical relief (different sizes of patch reefs. Daily surveillance for presence of large transient taxa suggested that visits by sharks, large jacks, monk seals, sea turtles, and dolphins were infrequent. Density estimates were made for all conspicuous invertebrate megafauna during initial and final assessments. Six common taxa provided 90% of these counts; nearly half were sea urchins. Percent cover also was recorded for coral and algal species on the patch reefs. Cover by live coral was low (about 7%) and dominated by a few species. Mean algal cover ranged from 32 to 77%. Such information on ecological characteristics of reefs may aid in understanding complex ecological processes and provides an earlier reference for current ecosystem studies.

  1. National Coral Reef Monitoring Program: Assessment of coral reef benthic communities in St. Croix, U.S. Virgin Islands from 2015-06-08 to 2015-06-19 (NCEI Accession 0151730)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic data collection for the National Coral Reef Ecosystem Monitoring Program (NCRMP) consists of two survey types: the Line Point-Intercept (LPI) method and the...

  2. Community change within a Caribbean coral reef Marine Protected Area following two decades of local management.

    Directory of Open Access Journals (Sweden)

    Mae M Noble

    Full Text Available Structural change in both the habitat and reef-associated fish assemblages within spatially managed coral reefs can provide key insights into the benefits and limitations of Marine Protected Areas (MPAs. While MPA zoning effects on particular target species are well reported, we are yet to fully resolve the various affects of spatial management on the structure of coral reef communities over decadal time scales. Here, we document mixed affects of MPA zoning on fish density, biomass and species richness over the 21 years since establishment of the Saba Marine Park (SMP. Although we found significantly greater biomass and species richness of reef-associated fishes within shallow habitats (5 meters depth closed to fishing, this did not hold for deeper (15 m habitats, and there was a widespread decline (38% decrease in live hard coral cover and a 68% loss of carnivorous reef fishes across all zones of the SMP from the 1990s to 2008. Given the importance of live coral for the maintenance and replenishment of reef fishes, and the likely role of chronic disturbance in driving coral decline across the region, we explore how local spatial management can help protect coral reef ecosystems within the context of large-scale environmental pressures and disturbances outside the purview of local MPA management.

  3. Legal Regime towards Protecting Coral Reefs: An International Perspective and Indian scenario

    Directory of Open Access Journals (Sweden)

    Rajesh Sehgal

    2006-09-01

    Full Text Available Corals Reefs are an important link in the marine biodiversity and millions of people depend on coral reefs for their sustenance and livelihood, yet these vital resources are in great danger today. Today, 27% of the world's coral reefs have been lost and 14% are predicted to be destroyed in the next 10 to 20 years due to the threats caused by human activities like over fishing, pollution, sedimentation and climate change. On the other hand, the current legal regimes towards protection of coral reefs are often inadequate. Though, most countries have legislation for reef conservation and additional national laws and multilateral environmental agreements have been adopted by the countries with assistance of the international and inter-governmental organization. There exists a wide array of local, state, national, and international initiatives that attempt, in varying degrees, to protect and preserve these ecosystems, still the implementation of these laws is difficult and completely lacking. This article primarily focuses on the principal national (India and international legal instruments that may provide for coral reef protection and provides recommendations for their better conservation. The article also highlight the condition of coral reefs and the difficulty in understanding their perilous situation.

  4. Community change within a Caribbean coral reef Marine Protected Area following two decades of local management.

    Science.gov (United States)

    Noble, Mae M; van Laake, Gregoor; Berumen, Michael L; Fulton, Christopher J

    2013-01-01

    Structural change in both the habitat and reef-associated fish assemblages within spatially managed coral reefs can provide key insights into the benefits and limitations of Marine Protected Areas (MPAs). While MPA zoning effects on particular target species are well reported, we are yet to fully resolve the various affects of spatial management on the structure of coral reef communities over decadal time scales. Here, we document mixed affects of MPA zoning on fish density, biomass and species richness over the 21 years since establishment of the Saba Marine Park (SMP). Although we found significantly greater biomass and species richness of reef-associated fishes within shallow habitats (5 meters depth) closed to fishing, this did not hold for deeper (15 m) habitats, and there was a widespread decline (38% decrease) in live hard coral cover and a 68% loss of carnivorous reef fishes across all zones of the SMP from the 1990s to 2008. Given the importance of live coral for the maintenance and replenishment of reef fishes, and the likely role of chronic disturbance in driving coral decline across the region, we explore how local spatial management can help protect coral reef ecosystems within the context of large-scale environmental pressures and disturbances outside the purview of local MPA management.

  5. Community Change within a Caribbean Coral Reef Marine Protected Area following Two Decades of Local Management

    KAUST Repository

    Noble, Mae M.

    2013-01-14

    Structural change in both the habitat and reef-associated fish assemblages within spatially managed coral reefs can provide key insights into the benefits and limitations of Marine Protected Areas (MPAs). While MPA zoning effects on particular target species are well reported, we are yet to fully resolve the various affects of spatial management on the structure of coral reef communities over decadal time scales. Here, we document mixed affects of MPA zoning on fish density, biomass and species richness over the 21 years since establishment of the Saba Marine Park (SMP). Although we found significantly greater biomass and species richness of reef-associated fishes within shallow habitats (5 meters depth) closed to fishing, this did not hold for deeper (15 m) habitats, and there was a widespread decline (38% decrease) in live hard coral cover and a 68% loss of carnivorous reef fishes across all zones of the SMP from the 1990s to 2008. Given the importance of live coral for the maintenance and replenishment of reef fishes, and the likely role of chronic disturbance in driving coral decline across the region, we explore how local spatial management can help protect coral reef ecosystems within the context of large-scale environmental pressures and disturbances outside the purview of local MPA management. © 2013 Noble et al.

  6. Spatiotemporal variations of live coral cover in the northern Mesoamerican Reef System, Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Linda M. Barranco

    2016-06-01

    Full Text Available Evaluating the response of coral assemblages to different disturbances is important because variations in species composition may have consequences for ecosystem functioning due to their different functional roles in coral reefs. This study evaluates changes in diversity, structure and composition of coral assemblages of the coral reefs of two national parks in the northern sector of the Mesoamerican Barrier Reef System spanning the period from 2006 to 2012, just after the impact of two hurricanes in the area. Coral assemblages in the Cancún National Park included fewer species and lower live coral coverage ( < 15% than those recorded in Cozumel. In the Cancún National Park, the species with the highest coral cover was Porites astreoides (more than 40% relative cover, and no significant temporal changes were observed in live coral cover and species composition. On the other hand, in the Cozumel National Park the dominant species were Agaricia agaricites, Siderastrea siderea and Porites astreoides, and the coral reefs showed an increase in live coral cover from 16% in 2006 to 29% in 2012. The dynamics of coral assemblages differed between the two parks: while there is an apparent stability in the current composition of the Cancún reefs, the Cozumel reefs show an increase in the abundance of the aforementioned dominant species. However, it is possible that the population characteristics of the species that dominate the coral assemblages in both national parks, such as those of fast population growth and of small colony size, do not entirely fulfill the main function of accretion and habitat heterogeneity, and more research is therefore needed to test this hypothesis.

  7. Chemically cued suppression of coral reef resilience: Where is the tipping point?

    Science.gov (United States)

    Brooker, Rohan M.; Hay, Mark E.; Dixson, Danielle L.

    2016-12-01

    Coral reefs worldwide are shifting from high-diversity, coral-dominated communities to low-diversity systems dominated by seaweeds. This shift can impact essential recovery processes such as larval recruitment and ecosystem resilience. Recent evidence suggests that chemical cues from certain corals attract, and from certain seaweeds suppress, recruitment of juvenile fishes, with loss of coral cover and increases in seaweed cover creating negative feedbacks that prevent reef recovery and sustain seaweed dominance. Unfortunately, the level of seaweed increase and coral decline that creates this chemically cued tipping point remains unknown, depriving managers of data-based targets to prevent damaging feedbacks. We conducted flume and field assays that suggest juvenile fishes sense and respond to cues produced by low levels of seaweed cover. However, the herbivore species we tested was more tolerant of degraded reef cues than non-herbivores, possibly providing some degree of resilience if these fishes recruit, consume macroalgae, and diminish negative cues.

  8. Bright spots among the world’s coral reefs

    Science.gov (United States)

    Cinner, Joshua E.; Huchery, Cindy; MacNeil, M. Aaron; Graham, Nicholas A. J.; McClanahan, Tim R.; Maina, Joseph; Maire, Eva; Kittinger, John N.; Hicks, Christina C.; Mora, Camilo; Allison, Edward H.; D'Agata, Stephanie; Hoey, Andrew; Feary, David A.; Crowder, Larry; Williams, Ivor D.; Kulbicki, Michel; Vigliola, Laurent; Wantiez, Laurent; Edgar, Graham; Stuart-Smith, Rick D.; Sandin, Stuart A.; Green, Alison L.; Hardt, Marah J.; Beger, Maria; Friedlander, Alan; Campbell, Stuart J.; Holmes, Katherine E.; Wilson, Shaun K.; Brokovich, Eran; Brooks, Andrew J.; Cruz-Motta, Juan J.; Booth, David J.; Chabanet, Pascale; Gough, Charlie; Tupper, Mark; Ferse, Sebastian C. A.; Sumaila, U. Rashid; Mouillot, David

    2016-07-01

    Ongoing declines in the structure and function of the world’s coral reefs require novel approaches to sustain these ecosystems and the millions of people who depend on them. A presently unexplored approach that draws on theory and practice in human health and rural development is to systematically identify and learn from the ‘outliers’—places where ecosystems are substantially better (‘bright spots’) or worse (‘dark spots’) than expected, given the environmental conditions and socioeconomic drivers they are exposed to. Here we compile data from more than 2,500 reefs worldwide and develop a Bayesian hierarchical model to generate expectations of how standing stocks of reef fish biomass are related to 18 socioeconomic drivers and environmental conditions. We identify 15 bright spots and 35 dark spots among our global survey of coral reefs, defined as sites that have biomass levels more than two standard deviations from expectations. Importantly, bright spots are not simply comprised of remote areas with low fishing pressure; they include localities where human populations and use of ecosystem resources is high, potentially providing insights into how communities have successfully confronted strong drivers of change. Conversely, dark spots are not necessarily the sites with the lowest absolute biomass and even include some remote, uninhabited locations often considered near pristine. We surveyed local experts about social, institutional, and environmental conditions at these sites to reveal that bright spots are characterized by strong sociocultural institutions such as customary taboos and marine tenure, high levels of local engagement in management, high dependence on marine resources, and beneficial environmental conditions such as deep-water refuges. Alternatively, dark spots are characterized by intensive capture and storage technology and a recent history of environmental shocks. Our results suggest that investments in strengthening fisheries

  9. Analysis on coral reefs mapping using SPOT5 data at the Dongsha Atoll

    Institute of Scientific and Technical Information of China (English)

    CHEN Jianyu; MAO Zhihua; ZHANG Huaguo; WU Junping; CHEN Xiaodong; PAN Delu

    2007-01-01

    Coral reefs are an sensitive-to-environment complex marine ecosystem. The ecosystem of corals is rich in biodiversity. Remote sensing offers a powerful tool for categorizing coral reefs and is the most cost - effective approach for the large - scale reef survey. The Dongsha Atoll, more than 300 km2 with an average depth of 10 m, is located at the northern continental margin of the South China Sea. It has been abused by destructive fishing during recent decades. Three satellite imageries (Quickbird2, ETM + and SPOTS) are used to evaluate the capabilities of SPOT5 imagery to provide data that are useful for categorizing the current distribution of coral reefs therein. During the data processing, unsupervised classification functions are adopted for ETM + and SPOT5 data, while the supervised classification method is used for Quickbird2. The classes are (or not) merged into coral reef, and then will be operated by vectorization, simplification, and topological analysis. There are 1 331 coral reefs larger than 100 m2 with a detection limit of 3 × 3 pixels at the multi - band data of Quickbird2, which is taken as the comparison baseline. The results extracted from SPOT5 and ETM images are less in number and area than those from the Quickbird2 image, whereas the results from SPOT5 data are better than those of ETM data at the silty lagoon due to its higher resolution. SPOT5 XS band 2 fails to distinguish the deep substrate inside the atoll compared with ETM data because of its poor penetration capability. Only SPOT XS band 1 cannot be used to differentiate coral reef from sand bottom. Merging the SPOT5 multi - bands data with the spatial resolution of SPOT5 pan - data and referring to ETM imagery are expected to provide an optimal satellite - based approach for mapping of coral reefs.

  10. Carrying capacity of coral reefs

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.

    The sustainable yield of a commercially exploited fishery is assessed by the biological and environmental factors (including fishing effort). These parameters with a reef are vastly diverse-size, location, species diversity, productivity type...

  11. Small Marine Protected Areas in Fiji Provide Refuge for Reef Fish Assemblages, Feeding Groups, and Corals

    Science.gov (United States)

    Pires, Mathias M.; Guimarães, Paulo Roberto; Hoey, Andrew S.; Hay, Mark E.

    2017-01-01

    The establishment of no-take marine protected areas (MPAs) on coral reefs is a common management strategy for conserving the diversity, abundance, and biomass of reef organisms. Generally, well-managed and enforced MPAs can increase or maintain the diversity and function of the enclosed coral reef, with some of the benefits extending to adjacent non-protected reefs. A fundamental question in coral reef conservation is whether these benefits arise within small MPAs (reef organisms is largely decoupled from local adult reproduction. We examined the structure of fish assemblages, composition of fish feeding groups, benthic cover, and key ecosystem processes (grazing, macroalgal browsing, and coral replenishment) in three small (0.5–0.8 km2) no-take MPAs and adjacent areas where fisheries are allowed (non-MPAs) on coral reefs in Fiji. The MPAs exhibited greater species richness, density, and biomass of fishes than non-MPAs. Furthermore, MPAs contained a greater abundance and biomass of grazing herbivores and piscivores as well as a greater abundance of cleaners than fished areas. We also found differences in fish associations when foraging, with feeding groups being generally more diverse and having greater biomass within MPAs than adjacent non-MPAs. Grazing by parrotfishes was 3–6 times greater, and macroalgal browsing was 3–5 times greater in MPAs than in non-MPAs. On average, MPAs had 260–280% as much coral cover and only 5–25% as much macroalgal cover as their paired non-MPA sites. Finally, two of the three MPAs had three-fold more coral recruits than adjacent non-MPAs. The results of this study indicate that small MPAs benefit not only populations of reef fishes, but also enhance ecosystem processes that are critical to reef resilience within the MPAs. PMID:28122006

  12. Evaluation of Stony Coral Indicators for Coral Reef ...

    Science.gov (United States)

    Colonies of reef-building stony corals at 57 stations around St. Croix, U.S. Virgin Islands were characterized by species, size and percentage of living tissue. Taxonomic, biological and physical indicators of coral condition were derived from these measurements and assessed for their response to gradients of human disturbance. The purpose of the study was to identify indicators that could be used for regulatory assessments under authority of the Clean Water Act--this requires that indicators distinguish anthropogenic disturbances from natural variation. Stony coral indicators were tested for correlation with human disturbance across gradients located on three different sides of the island. At the most intensely disturbed location, five of eight primary indicators were highly correlated with distance from the source of disturbance: Coral taxa richness, average colony size, the coefficient of variation of colony size (an indicator of colony size heterogeneity), total topographic coral surface area, and live coral surface area. An additional set of exploratory indicators related to rarity, reproductive and spawning mode, and taxonomic identity were also screened for association with disturbance at the same location. For the other two locations, there were no significant changes in indicator values and therefore no discernible effects of human activity. Coral indicators demonstrated sufficient precision to detect levels of change that would be applicable in a regio

  13. Understanding Coral Reef Fish Characteristics Using Videogrammetry in Hanauma and Maunalua Bays, Oahu, Hawaii during 2007 (NODC Accession 0042353)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Videogrammetry data taken in 2007 are used for a study of fish within coral reef ecosystems. We attempted to generate or find information on abundance, growth,...

  14. Underwater temperature data collected from off-shore coral reefs of the Florida Keys, U.S.A.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey (USGS) Coral Reef Ecosystems Studies (CREST) project (http://coastal.er.usgs.gov/crest/) provides science that helps resource managers...

  15. Understanding coral reef fish characteristics using videogrammetry in Hanauma and Maunalua Bays, Oahu, Hawaii during 2007 (NODC Accession 0042353)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Videogrammetry data taken in 2007 are used for a study of fish within coral reef ecosystems. We attempted to generate or find information on abundance, growth,...

  16. 75 FR 39917 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coral and Coral Reefs off the...

    Science.gov (United States)

    2010-07-13

    ..., and South Atlantic; Coral and Coral Reefs off the Southern Atlantic States; Exempted Fishing Permit... for Coral, Coral Reefs, and Live/Hardbottom Habitat of the South Atlantic Region. The applicant has... Coral Reef Research Foundation (CRRF, http://www.coralreefresearchfoundation.org/ ). Samples would be...

  17. 76 FR 30110 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coral and Coral Reefs Off the...

    Science.gov (United States)

    2011-05-24

    ..., and South Atlantic; Coral and Coral Reefs Off the Southern Atlantic States; Exempted Fishing Permit... implementing the Fishery Management Plan for Coral, Coral Reefs, and Live/Hardbottom Habitat of the South... Cancer Institute ( http://www.cancer.gov/ ) and the Coral Reef Research Foundation (CRRF, http://www...

  18. Effects of seawater acidification on a coral reef meiofauna community

    Science.gov (United States)

    Sarmento, V. C.; Souza, T. P.; Esteves, A. M.; Santos, P. J. P.

    2015-09-01

    Despite the increasing risk that ocean acidification will modify benthic communities, great uncertainty remains about how this impact will affect the lower trophic levels, such as members of the meiofauna. A mesocosm experiment was conducted to investigate the effects of water acidification on a phytal meiofauna community from a coral reef. Community samples collected from the coral reef subtidal zone (Recife de Fora Municipal Marine Park, Porto Seguro, Bahia, Brazil), using artificial substrate units, were exposed to a control pH (ambient seawater) and to three levels of seawater acidification (pH reductions of 0.3, 0.6, and 0.9 units below ambient) and collected after 15 and 30 d. After 30 d of exposure, major changes in the structure of the meiofauna community were observed in response to reduced pH. The major meiofauna groups showed divergent responses to acidification. Harpacticoida and Polychaeta densities did not show significant differences due to pH. Nematoda, Ostracoda, Turbellaria, and Tardigrada exhibited their highest densities in low-pH treatments (especially at the pH reduction of 0.6 units, pH 7.5), while harpacticoid nauplii were strongly negatively affected by low pH. This community-based mesocosm study supports previous suggestions that ocean acidification induces important changes in the structure of marine benthic communities. Considering the importance of meiofauna in the food web of coral reef ecosystems, the results presented here demonstrate that the trophic functioning of coral reefs is seriously threatened by ocean acidification.

  19. Mangrove habitats provide refuge from climate change for reef-building corals

    Directory of Open Access Journals (Sweden)

    K. K. Yates

    2014-03-01

    , hydrographic conditions, and biological influences on seawater chemistry generate chemical conditions that buffer against ocean acidification. This previously undocumented refuge for corals provides evidence for adaptation of coastal organisms and ecosystem transition due to recent climate change. Identifying and protecting other natural, non-reef coral refuges is critical for sustaining corals and other reef species into the future.

  20. Mangrove habitats provide refuge from climate change for reef-building corals

    Science.gov (United States)

    Yates, K. K.; Rogers, C. S.; Herlan, J. J.; Brooks, G. R.; Smiley, N. A.; Larson, R. A.

    2014-03-01

    conditions, and biological influences on seawater chemistry generate chemical conditions that buffer against ocean acidification. This previously undocumented refuge for corals provides evidence for adaptation of coastal organisms and ecosystem transition due to recent climate change. Identifying and protecting other natural, non-reef coral refuges is critical for sustaining corals and other reef species into the future.

  1. Climate Change, Human Impacts, and the Resilience of Coral Reefs

    Science.gov (United States)

    Hughes, T. P.; Baird, A. H.; Bellwood, D. R.; Card, M.; Connolly, S. R.; Folke, C.; Grosberg, R.; Hoegh-Guldberg, O.; Jackson, J. B. C.; Kleypas, J.; Lough, J. M.; Marshall, P.; Nyström, M.; Palumbi, S. R.; Pandolfi, J. M.; Rosen, B.; Roughgarden, J.

    2003-08-01

    The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming.

  2. Coral Reefs and People in a High-CO2 World: Where Can Science Make a Difference to People?

    OpenAIRE

    Pendleton, Linwood; Comte, Adrien; Langdon, Chris; Ekstrom, Julia A.; Sarah R Cooley; Suatoni, Lisa; Beck, Michael W.; Brander, Luke M.; Burke, Lauretta; Cinner, Josh E.; Doherty, Carolyn; Edwards, Peter E.T.; Gledhill, Dwight; Jiang, Li-Qing; van Hooidonk, Ruben J.

    2016-01-01

    Reefs and People at Risk Increasing levels of carbon dioxide in the atmosphere put shallow, warm-water coral reef ecosystems, and the people who depend upon them at risk from two key global environmental stresses: 1) elevated sea surface temperature (that can cause coral bleaching and related mortality), and 2) ocean acidification. These global stressors: cannot be avoided by local management, compound local stressors, and hasten the loss of ecosystem services. Impacts to people will be most ...

  3. Temporal patterns in coral reef, seagrass and mangrove communities from Chengue bay CARICOMP site (Colombia): 1993-2008

    OpenAIRE

    2015-01-01

    Few monitoring programs have simultaneously assessed the dynamics of linked marine ecosystems (coral reefs, seagrass beds and mangroves) to document their temporal and spatial variability. Based on CARICOMP protocol we evaluated permanent stations in coral reefs, seagrass beds and mangroves from 1993 to 2008 in Chengue Bay at the Tayrona Natural Park, Colombian Caribbean. Overall, the studied ecosystems showed a remarkable stability pattern over the monitoring period. While there were annual ...

  4. The COral-REef Front (COREF Project

    Directory of Open Access Journals (Sweden)

    John A. and Katherine G. Jackson

    2007-09-01

    Full Text Available The First International Workshop on the COral-REef Front (COREF project was held on 14−19 January 2007 in Okinawa-jima, southwestern Japan to discuss objectives, required laboratory analyses and techniques, potential drilling sites, and scientific proposals for the Integrated Ocean Drilling Program (IODP and the International Continental Scientific Drilling Program (ICDP. This article briefly introduces the project and reports the outcome of the First International Workshop on the COREF Project.

  5. Threatened Reef Corals of the World

    OpenAIRE

    Danwei Huang

    2012-01-01

    A substantial proportion of the world's living species, including one-third of the reef-building corals, are threatened with extinction and in pressing need of conservation action. In order to reduce biodiversity loss, it is important to consider species' contribution to evolutionary diversity along with their risk of extinction for the purpose of setting conservation priorities. Here I reconstruct the most comprehensive tree of life for the order Scleractinia (1,293 species) that includes al...

  6. The implications of recurrent disturbances within the world's hottest coral reef.

    Science.gov (United States)

    Bento, Rita; Hoey, Andrew S; Bauman, Andrew G; Feary, David A; Burt, John A

    2016-04-30

    Determining how coral ecosystems are structured within extreme environments may provide insights into how coral reefs are impacted by future climate change. Benthic community structure was examined within the Persian Gulf, and adjacent Musandam and northern Oman regions across a 3-year period (2008-2011) in which all regions were exposed to major disturbances. Although there was evidence of temporal switching in coral composition within regions, communities predominantly reflected local environmental conditions and the disturbance history of each region. Gulf reefs showed little change in coral composition, being dominated by stress-tolerant Faviidae and Poritidae across the 3 years. In comparison, Musandam and Oman coral communities were comprised of stress-sensitive Acroporidae and Pocilloporidae; Oman communities showed substantial declines in such taxa and increased cover of stress-tolerant communities. Our results suggest that coral communities may persist within an increasingly disturbed future environment, albeit in a much more structurally simple configuration.

  7. Comparative Effects of Different Disturbances in Coral Reef Habitats in Moorea, French Polynesia

    Directory of Open Access Journals (Sweden)

    Mélanie L. Trapon

    2011-01-01

    Full Text Available Degradation and loss of critical coastal habitats has significant ramifications for marine fisheries, such that knowledge of changes in habitat quality and quantity are fundamental to effective ecosystem management. This study explores changes in the structure of coral reef habitats, specifically changes in coral cover and composition, in Moorea, French Polynesia, to assess the independent and combined effects of different disturbances since 1979. During this period, reefs on the north coast have been subject to coral bleaching, severe tropical storms, as well as outbreaks of Acanthaster. Coral cover varied significantly among years, showing marked declines during some, but not all, disturbances. The greatest rates of coral loss coincided with outbreaks of A. planci. Moreover, successive disturbances have had differential effects among coral genera, leading to strong directional shifts in coral composition. Acropora is declining in abundance and coral assemblages are becoming increasingly dominated by Pocillopora and Porites. Observed changes in the cover and composition of corals are likely to have further significant impacts on the reef fish assemblages. Given that significant disturbances have been mostly associated with outbreaks of A. planci, rather than climate change, effective ecosystem management may reduce and/or delay impending effects of climate change.

  8. Disturbance and the dynamics of coral cover on the Great Barrier Reef (1995-2009.

    Directory of Open Access Journals (Sweden)

    Kate Osborne

    Full Text Available Coral reef ecosystems worldwide are under pressure from chronic and acute stressors that threaten their continued existence. Most obvious among changes to reefs is loss of hard coral cover, but a precise multi-scale estimate of coral cover dynamics for the Great Barrier Reef (GBR is currently lacking. Monitoring data collected annually from fixed sites at 47 reefs across 1300 km of the GBR indicate that overall regional coral cover was stable (averaging 29% and ranging from 23% to 33% cover across years with no net decline between 1995 and 2009. Subregional trends (10-100 km in hard coral were diverse with some being very dynamic and others changing little. Coral cover increased in six subregions and decreased in seven subregions. Persistent decline of corals occurred in one subregion for hard coral and Acroporidae and in four subregions in non-Acroporidae families. Change in Acroporidae accounted for 68% of change in hard coral. Crown-of-thorns starfish (Acanthaster planci outbreaks and storm damage were responsible for more coral loss during this period than either bleaching or disease despite two mass bleaching events and an increase in the incidence of coral disease. While the limited data for the GBR prior to the 1980's suggests that coral cover was higher than in our survey, we found no evidence of consistent, system-wide decline in coral cover since 1995. Instead, fluctuations in coral cover at subregional scales (10-100 km, driven mostly by changes in fast-growing Acroporidae, occurred as a result of localized disturbance events and subsequent recovery.

  9. Disturbance and the dynamics of coral cover on the Great Barrier Reef (1995-2009).

    Science.gov (United States)

    Osborne, Kate; Dolman, Andrew M; Burgess, Scott C; Johns, Kerryn A

    2011-03-10

    Coral reef ecosystems worldwide are under pressure from chronic and acute stressors that threaten their continued existence. Most obvious among changes to reefs is loss of hard coral cover, but a precise multi-scale estimate of coral cover dynamics for the Great Barrier Reef (GBR) is currently lacking. Monitoring data collected annually from fixed sites at 47 reefs across 1300 km of the GBR indicate that overall regional coral cover was stable (averaging 29% and ranging from 23% to 33% cover across years) with no net decline between 1995 and 2009. Subregional trends (10-100 km) in hard coral were diverse with some being very dynamic and others changing little. Coral cover increased in six subregions and decreased in seven subregions. Persistent decline of corals occurred in one subregion for hard coral and Acroporidae and in four subregions in non-Acroporidae families. Change in Acroporidae accounted for 68% of change in hard coral. Crown-of-thorns starfish (Acanthaster planci) outbreaks and storm damage were responsible for more coral loss during this period than either bleaching or disease despite two mass bleaching events and an increase in the incidence of coral disease. While the limited data for the GBR prior to the 1980's suggests that coral cover was higher than in our survey, we found no evidence of consistent, system-wide decline in coral cover since 1995. Instead, fluctuations in coral cover at subregional scales (10-100 km), driven mostly by changes in fast-growing Acroporidae, occurred as a result of localized disturbance events and subsequent recovery.

  10. CORAL REEFS. Genomic determinants of coral heat tolerance across latitudes.

    Science.gov (United States)

    Dixon, Groves B; Davies, Sarah W; Aglyamova, Galina A; Meyer, Eli; Bay, Line K; Matz, Mikhail V

    2015-06-26

    As global warming continues, reef-building corals could avoid local population declines through "genetic rescue" involving exchange of heat-tolerant genotypes across latitudes, but only if latitudinal variation in thermal tolerance is heritable. Here, we show an up-to-10-fold increase in odds of survival of coral larvae under heat stress when their parents come from a warmer lower-latitude location. Elevated thermal tolerance was associated with heritable differences in expression of oxidative, extracellular, transport, and mitochondrial functions that indicated a lack of prior stress. Moreover, two genomic regions strongly responded to selection for thermal tolerance in interlatitudinal crosses. These results demonstrate that variation in coral thermal tolerance across latitudes has a strong genetic basis and could serve as raw material for natural selection. Copyright © 2015, American Association for the Advancement of Science.

  11. Ecological States and the Resilience of Coral Reefs

    Directory of Open Access Journals (Sweden)

    Tim McClanahan

    2002-12-01

    Full Text Available We review the evidence for multiple ecological states and the factors that create ecological resilience in coral reef ecosystems. There are natural differences among benthic communities along gradients of water temperature, light, nutrients, and organic matter associated with upwelling-downwelling and onshore-offshore systems. Along gradients from oligotrophy to eutrophy, plant-animal symbioses tend to decrease, and the abundance of algae and heterotrophic suspension feeders and the ratio of organic to inorganic carbon production tend to increase. Human influences such as fishing, increased organic matter and nutrients, sediments, warm water, and transportation of xenobiotics and diseases are common causes of a large number of recently reported ecological shifts. It is often the interaction of persistent and multiple synergistic disturbances that causes permanent ecological transitions, rather than the succession of individual short-term disturbances. For example, fishing can remove top-level predators, resulting in the ecological release of prey such as sea urchins and coral-eating invertebrates. When sea urchins are not common because of unsuitable habitat, recruitment limitations, and diseases, and when overfishing removes herbivorous fish, frondose brown algae can dominate. Terrigenous sediments carried onto reefs as a result of increased soil erosion largely promote the dominance of turf or articulated green algae. Elevated nutrients and organic matter can increase internal eroders of reef substratum and a mixture of filamentous algae. Local conservation actions that attempt to reduce fishing and terrestrial influences promote the high production of inorganic carbon that is necessary for reef growth. However, global climate change threatens to undermine such actions because of increased bleaching and mortality caused by warm-water anomalies, weakened coral skeletons caused by reduced aragonite availability in reef waters, and increased

  12. Coral Reef Community Composition in the Context of Disturbance History on the Great Barrier Reef, Australia

    Science.gov (United States)

    Graham, Nicholas A. J.; Chong-Seng, Karen M.; Huchery, Cindy; Januchowski-Hartley, Fraser A.; Nash, Kirsty L.

    2014-01-01

    Much research on coral reefs has documented differential declines in coral and associated organisms. In order to contextualise this general degradation, research on community composition is necessary in the context of varied disturbance histories and the biological processes and physical features thought to retard or promote recovery. We conducted a spatial assessment of coral reef communities across five reefs of the central Great Barrier Reef, Australia, with known disturbance histories, and assessed patterns of coral cover and community composition related to a range of other variables thought to be important for reef dynamics. Two of the reefs had not been extensively disturbed for at least 15 years prior to the surveys. Three of the reefs had been severely impacted by crown-of-thorns starfish outbreaks and coral bleaching approximately a decade before the surveys, from which only one of them was showing signs of recovery based on independent surveys. We incorporated wave exposure (sheltered and exposed) and reef zone (slope, crest and flat) into our design, providing a comprehensive assessment of the spatial patterns in community composition on these reefs. Categorising corals into life history groupings, we document major coral community differences in the unrecovered reefs, compared to the composition and covers found on the undisturbed reefs. The recovered reef, despite having similar coral cover, had a different community composition from the undisturbed reefs, which may indicate slow successional processes, or a different natural community dominance pattern due to hydrology and other oceanographic factors. The variables that best correlated with patterns in the coral community among sites included the density of juvenile corals, herbivore fish biomass, fish species richness and the cover of macroalgae. Given increasing impacts to the Great Barrier Reef, efforts to mitigate local stressors will be imperative to encouraging coral communities to persist into

  13. Coral reef community composition in the context of disturbance history on the Great Barrier Reef, Australia.

    Directory of Open Access Journals (Sweden)

    Nicholas A J Graham

    Full Text Available Much research on coral reefs has documented differential declines in coral and associated organisms. In order to contextualise this general degradation, research on community composition is necessary in the context of varied disturbance histories and the biological processes and physical features thought to retard or promote recovery. We conducted a spatial assessment of coral reef communities across five reefs of the central Great Barrier Reef, Australia, with known disturbance histories, and assessed patterns of coral cover and community composition related to a range of other variables thought to be important for reef dynamics. Two of the reefs had not been extensively disturbed for at least 15 years prior to the surveys. Three of the reefs had been severely impacted by crown-of-thorns starfish outbreaks and coral bleaching approximately a decade before the surveys, from which only one of them was showing signs of recovery based on independent surveys. We incorporated wave exposure (sheltered and exposed and reef zone (slope, crest and flat into our design, providing a comprehensive assessment of the spatial patterns in community composition on these reefs. Categorising corals into life history groupings, we document major coral community differences in the unrecovered reefs, compared to the composition and covers found on the undisturbed reefs. The recovered reef, despite having similar coral cover, had a different community composition from the undisturbed reefs, which may indicate slow successional processes, or a different natural community dominance pattern due to hydrology and other oceanographic factors. The variables that best correlated with patterns in the coral community among sites included the density of juvenile corals, herbivore fish biomass, fish species richness and the cover of macroalgae. Given increasing impacts to the Great Barrier Reef, efforts to mitigate local stressors will be imperative to encouraging coral

  14. Coral reef community composition in the context of disturbance history on the Great Barrier Reef, Australia.

    Science.gov (United States)

    Graham, Nicholas A J; Chong-Seng, Karen M; Huchery, Cindy; Januchowski-Hartley, Fraser A; Nash, Kirsty L

    2014-01-01

    Much research on coral reefs has documented differential declines in coral and associated organisms. In order to contextualise this general degradation, research on community composition is necessary in the context of varied disturbance histories and the biological processes and physical features thought to retard or promote recovery. We conducted a spatial assessment of coral reef communities across five reefs of the central Great Barrier Reef, Australia, with known disturbance histories, and assessed patterns of coral cover and community composition related to a range of other variables thought to be important for reef dynamics. Two of the reefs had not been extensively disturbed for at least 15 years prior to the surveys. Three of the reefs had been severely impacted by crown-of-thorns starfish outbreaks and coral bleaching approximately a decade before the surveys, from which only one of them was showing signs of recovery based on independent surveys. We incorporated wave exposure (sheltered and exposed) and reef zone (slope, crest and flat) into our design, providing a comprehensive assessment of the spatial patterns in community composition on these reefs. Categorising corals into life history groupings, we document major coral community differences in the unrecovered reefs, compared to the composition and covers found on the undisturbed reefs. The recovered reef, despite having similar coral cover, had a different community composition from the undisturbed reefs, which may indicate slow successional processes, or a different natural community dominance pattern due to hydrology and other oceanographic factors. The variables that best correlated with patterns in the coral community among sites included the density of juvenile corals, herbivore fish biomass, fish species richness and the cover of macroalgae. Given increasing impacts to the Great Barrier Reef, efforts to mitigate local stressors will be imperative to encouraging coral communities to persist into

  15. The continuing decline of coral reefs in Bahrain.

    Science.gov (United States)

    Burt, John A; Al-Khalifa, Khalifa; Khalaf, Ebtesam; Alshuwaikh, Bassem; Abdulwahab, Ahmed

    2013-07-30

    Historically coral reefs of Bahrain were among the most extensive in the southern basin of the Arabian Gulf. However, Bahrain's reefs have undergone significant decline in the last four decades as a result of large-scale coastal development and elevated sea surface temperature events. Here we quantitatively surveyed six sites including most major coral reef habitats around Bahrain and a reef located 72 km offshore. Fleshy and turf algae now dominate Bahrain's reefs (mean: 72% cover), and live coral cover is low (mean: 5.1%). Formerly dominant Acropora were not observed at any site. The offshore Bulthama reef had the highest coral cover (16.3%) and species richness (22 of the 23 species observed, 13 of which were exclusive to this site). All reefs for which recent and historical data are available show continued degradation, and it is unlikely that they will recover under continuing coastal development and projected climate change impacts. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. The role of turtles as coral reef macroherbivores

    KAUST Repository

    Goatley, Christopher H. R.

    2012-06-29

    Herbivory is widely accepted as a vital function on coral reefs. To date, the majority of studies examining herbivory in coral reef environments have focused on the roles of fishes and/or urchins, with relatively few studies considering the potential role of macroherbivores in reef processes. Here, we introduce evidence that highlights the potential role of marine turtles as herbivores on coral reefs. While conducting experimental habitat manipulations to assess the roles of herbivorous reef fishes we observed green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) showing responses that were remarkably similar to those of herbivorous fishes. Reducing the sediment load of the epilithic algal matrix on a coral reef resulted in a forty-fold increase in grazing by green turtles. Hawksbill turtles were also observed to browse transplanted thalli of the macroalga Sargassum swartzii in a coral reef environment. These responses not only show strong parallels to herbivorous reef fishes, but also highlight that marine turtles actively, and intentionally, remove algae from coral reefs. When considering the size and potential historical abundance of marine turtles we suggest that these potentially valuable herbivores may have been lost from many coral reefs before their true importance was understood. © 2012 Goatley et al.

  17. The role of turtles as coral reef macroherbivores.

    Directory of Open Access Journals (Sweden)

    Christopher H R Goatley

    Full Text Available Herbivory is widely accepted as a vital function on coral reefs. To date, the majority of studies examining herbivory in coral reef environments have focused on the roles of fishes and/or urchins, with relatively few studies considering the potential role of macroherbivores in reef processes. Here, we introduce evidence that highlights the potential role of marine turtles as herbivores on coral reefs. While conducting experimental habitat manipulations to assess the roles of herbivorous reef fishes we observed green turtles (Chelonia mydas and hawksbill turtles (Eretmochelys imbricata showing responses that were remarkably similar to those of herbivorous fishes. Reducing the sediment load of the epilithic algal matrix on a coral reef resulted in a forty-fold increase in grazing by green turtles. Hawksbill turtles were also observed to browse transplanted thalli of the macroalga Sargassum swartzii in a coral reef environment. These responses not only show strong parallels to herbivorous reef fishes, but also highlight that marine turtles actively, and intentionally, remove algae from coral reefs. When considering the size and potential historical abundance of marine turtles we suggest that these potentially valuable herbivores may have been lost from many coral reefs before their true importance was understood.

  18. Simulations of long-term community dynamics in coral reefs--how perturbations shape trajectories.

    Directory of Open Access Journals (Sweden)

    Andreas Kubicek

    Full Text Available Tropical coral reefs feature extraordinary biodiversity and high productivity rates in oligotrophic waters. Due to increasing frequencies of perturbations--anthropogenic and natural--many reefs are under threat. Such perturbations often have devastating effects on these unique ecosystems and especially if they occur simultaneously and amplify each other's impact, they might trigger a phase shift and create irreversible conditions.We developed a generic, spatially explicit, individual-based model in which competition drives the dynamics of a virtual benthic reef community--comprised of scleractinian corals and algae--under different environmental settings. Higher system properties, like population dynamics or community composition arise through self-organization as emergent properties. The model was parameterized for a typical coral reef site at Zanzibar, Tanzania and features coral bleaching and physical disturbance regimes as major sources of perturbations. Our results show that various types and modes (intensities and frequencies of perturbations create diverse outcomes and that the switch from high diversity to single species dominance can be evoked by small changes in a key parameter. Here we extend the understanding of coral reef resilience and the identification of key processes, drivers and respective thresholds, responsible for changes in local situations. One future goal is to provide a tool which may aid decision making processes in management of coral reefs.

  19. STUDY OF CORAL REEF DISTRIBUTION AROUND BADUNG STRAIT USING ALOS SATELLITE DATA

    Directory of Open Access Journals (Sweden)

    Suciati -

    2012-11-01

    Full Text Available Coral reef ecosystem has become a centre of interest because of the development of marine tourism development,coral fragment trade, and other activities that are able to destroy coral reef ecosystem. ALOS with AVNIR-2 sensor wasselected because it has 3 visible spectrums which have the ability of penetration into water column, also it have highenough of spatial resolution i.e.10 meters.The aims of this research are: 1 to identify the level of accuracy of ALOS satellite image in activity for coral reefdistribution mapping and 2 to identify the general condition of coral reefs in around Badung Strait.Preliminary processes of image processing are geometric correction and atmosphere correction. Water columneffect was reduced by Lyzenga Algorithm. Five classes were determined by multispectral classification process e.i. coral,vegetation, sand, rubble of coral and substrate. Ground check was done to identify the accuracy level. The methodaccuracy by Lillesand and Kiefer was used in this research.The result of accuracy test shows that classification accuracy was 87.16% for overall accuracy. Results of imageinterpretation show that live coral in around Badung strait is estimated to have about 141,056 hectares width. It wascovering Denpasar Regency in the east and south-east side of Serangan Island with the fringing reef type; KlungkungRegency in the west side of Lembongan Island with the fringing reef type and in the south side with the platform type,while in Gianyar Regency was not found the coral reef distribution.

  20. The impacts of tourism on coral reef conservation awareness and support in coastal communities in Belize

    Science.gov (United States)

    Diedrich, A.

    2007-12-01

    Marine recreational tourism is one of a number of threats to the Belize Barrier Reef but, conversely, represents both a motivation and source of resources for its conservation. The growth of tourism in Belize has resulted in the fact that many coastal communities are in varying stages of a socio-economic shift from dependence on fishing to dependence on tourism. In a nation becoming increasingly dependent on the health of its coral reef ecosystems for economic prosperity, a shift from extractive uses to their preservation is both necessary and logical. Through examining local perception data in five coastal communities in Belize, each attracting different levels of coral reef related tourism, this analysis is intended to explore the relationship between tourism development and local coral reef conservation awareness and support. The results of the analysis show a positive correlation between tourism development and coral reef conservation awareness and support in the study communities. The results also show a positive correlation between tourism development and local perceptions of quality of life, a trend that is most likely the source of the observed relationship between tourism and conservation. The study concludes that, because the observed relationship may be dependent on continued benefits from tourism as opposed to a perceived crisis in coral reef health, Belize must pay close attention to tourism impacts in the future. Failure to do this could result in a destructive feedback loop that would contribute to the degradation of the reef and, ultimately, Belize’s diminished competitiveness in the ecotourism market.

  1. Temperature variability caused by internal tides in the coral reef ecosystem of Hanauma bay, Hawai'i

    Science.gov (United States)

    Smith, Katharine A.; Rocheleau, Greg; Merrifield, Mark A.; Jaramillo, Sergio; Pawlak, Geno

    2016-03-01

    Hanauma Bay Nature Preserve is a shallow bay (15 m depth) become dominated by large semidiurnal variations (up to 2.7 °C) that are attributed to the internal tide. These temperature drops caused by the internal tide occur consistently twice a day under summer stratification at depths as shallow as 15 m, while smaller temperature drops (up to 1.8 °C) occur occasionally at 5 m. Although semidiurnal band temperatures vary seasonally, semidiurnal band currents exhibit similar magnitudes in spring and summer. This suggests that the weak temperature fluctuations in spring are due to the bay residing entirely in the upper mixed layer at this time of year, while internal tide energy continues to influence currents. Observations made along a cross-shore/vertical transect at the center of the bay with an autonomous underwater vehicle highlight the structure of cold intrusions that fill a large portion of the bay as well as the relationship between temperature, salinity, chlorophyll, and backscatter. Near-bottom, advective heat flux estimates at the mouth of the bay indicate that the internal tide tends to advect cold water into the bay primarily on the northeast side of the bay entrance, with cold water outflow on the opposite side. The observations highlight the role of the internal tide along with seasonal changes in stratification in temperature variability in shallow ecosystems, particularly those close to generation sites.

  2. Habitats as Surrogates of Taxonomic and Functional Fish Assemblages in Coral Reef Ecosystems: A Critical Analysis of Factors Driving Effectiveness

    Science.gov (United States)

    Van Wynsberge, Simon; Andréfouët, Serge; Hamel, Mélanie A.; Kulbicki, Michel

    2012-01-01

    Species check-lists are helpful to establish Marine Protected Areas (MPAs) and protect local richness, endemicity, rarity, and biodiversity in general. However, such exhaustive taxonomic lists (i.e., true surrogate of biodiversity) require extensive and expensive censuses, and the use of estimator surrogates (e.g., habitats) is an appealing alternative. In truth, surrogate effectiveness appears from the literature highly variable both in marine and terrestrial ecosystems, making it difficult to provide practical recommendations for managers. Here, we evaluate how the biodiversity reference data set and its inherent bias can influence effectiveness. Specifically, we defined habitats by geomorphology, rugosity, and benthic cover and architecture criteria, and mapped them with satellite images for a New-Caledonian site. Fish taxonomic and functional lists were elaborated from Underwater Visual Censuses, stratified according to geomorphology and exposure. We then tested if MPA networks designed to maximize habitat richness, diversity and rarity could also effectively maximize fish richness, diversity, and rarity. Effectiveness appeared highly sensitive to the fish census design itself, in relation to the type of habitat map used and the scale of analysis. Spatial distribution of habitats (estimator surrogate’s distribution), quantity and location of fish census stations (target surrogate’s sampling), and random processes in the MPA design all affected effectiveness to the point that one small change in the data set could lead to opposite conclusions. We suggest that previous conclusions on surrogacy effectiveness, either positive or negative, marine or terrestrial, should be considered with caution, except in instances where very dense data sets were used without pseudo-replication. Although this does not rule out the validity of using surrogates of species lists for conservation planning, the critical joint examination of both target and estimator surrogates is

  3. Habitats as surrogates of taxonomic and functional fish assemblages in coral reef ecosystems: a critical analysis of factors driving effectiveness.

    Directory of Open Access Journals (Sweden)

    Simon Van Wynsberge

    Full Text Available Species check-lists are helpful to establish Marine Protected Areas (MPAs and protect local richness, endemicity, rarity, and biodiversity in general. However, such exhaustive taxonomic lists (i.e., true surrogate of biodiversity require extensive and expensive censuses, and the use of estimator surrogates (e.g., habitats is an appealing alternative. In truth, surrogate effectiveness appears from the literature highly variable both in marine and terrestrial ecosystems, making it difficult to provide practical recommendations for managers. Here, we evaluate how the biodiversity reference data set and its inherent bias can influence effectiveness. Specifically, we defined habitats by geomorphology, rugosity, and benthic cover and architecture criteria, and mapped them with satellite images for a New-Caledonian site. Fish taxonomic and functional lists were elaborated from Underwater Visual Censuses, stratified according to geomorphology and exposure. We then tested if MPA networks designed to maximize habitat richness, diversity and rarity could also effectively maximize fish richness, diversity, and rarity. Effectiveness appeared highly sensitive to the fish census design itself, in relation to the type of habitat map used and the scale of analysis. Spatial distribution of habitats (estimator surrogate's distribution, quantity and location of fish census stations (target surrogate's sampling, and random processes in the MPA design all affected effectiveness to the point that one small change in the data set could lead to opposite conclusions. We suggest that previous conclusions on surrogacy effectiveness, either positive or negative, marine or terrestrial, should be considered with caution, except in instances where very dense data sets were used without pseudo-replication. Although this does not rule out the validity of using surrogates of species lists for conservation planning, the critical joint examination of both target and estimator

  4. Coral Reef and Hardbottom from Unified Florida Reef Tract Map (NODC Accession 0123059)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a subset of the Unified Map representing Coral reef and Hardbottom areas. Version 1.1 - December 2013. The Unified Florida Reef Tract Map (Unified...

  5. Coral mortality in reefs: The cause and effect; A central concern for reef monitoring

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.

    are destructive and long-lasting. The coral reef monitoring programme therefore aims at identifying reefs in various localities inorder to monitor them for various diseases and hence evolve strategies to eliminate the causes of diseases...

  6. Modeling regional coral reef responses to global warming and changes in ocean chemistry: Caribbean case study

    Science.gov (United States)

    Buddemeier, R.W.; Lane, D.R.; Martinich, J.A.

    2011-01-01

    Climatic change threatens the future of coral reefs in the Caribbean and the important ecosystem services they provide. We used a simulation model [Combo ("COral Mortality and Bleaching Output")] to estimate future coral cover in the part of the eastern Caribbean impacted by a massive coral bleaching event in 2005. Combo calculates impacts of future climate change on coral reefs by combining impacts from long-term changes in average sea surface temperature (SST) and ocean acidification with impacts from episodic high temperature mortality (bleaching) events. We used mortality and heat dose data from the 2005 bleaching event to select historic temperature datasets, to use as a baseline for running Combo under different future climate scenarios and sets of assumptions. Results suggest a bleak future for coral reefs in the eastern Caribbean. For three different emissions scenarios from the Intergovernmental Panel on Climate Change (IPCC; B1, A1B, and A1FI), coral cover on most Caribbean reefs is projected to drop below 5% by the year 2035, if future mortality rates are equivalent to some of those observed in the 2005 event (50%). For a scenario where corals gain an additional 1-1. 5??C of heat tolerance through a shift in the algae that live in the coral tissue, coral cover above 5% is prolonged until 2065. Additional impacts such as storms or anthropogenic damage could result in declines in coral cover even faster than those projected here. These results suggest the need to identify and preserve the locations that are likely to have a higher resiliency to bleaching to save as many remnant populations of corals as possible in the face of projected wide-spread coral loss. ?? 2011 The Author(s).

  7. Expansion of corals on temperate reefs: direct and indirect effects of marine heatwaves

    Science.gov (United States)

    Tuckett, C. A.; de Bettignies, T.; Fromont, J.; Wernberg, T.

    2017-09-01

    Globally, many temperate marine communities have experienced significant temperature increases over recent decades in the form of gradual warming and heatwaves. As a result, these communities are shifting towards increasingly subtropical and tropical species compositions. Expanding coral populations have been reported from several temperate reef ecosystems along warming coastlines; these changes have been attributed to direct effects of gradual warming over decades. In contrast, increases in coral populations following shorter-term extreme warming events have rarely been documented. In this study, we compared coral populations on 17 temperate reefs in Western Australia before (2005/06) and after (2013) multiple marine heatwaves (2010-2012) affected the entire coastline. We hypothesised that coral communities would expand and change as a consequence of increasing local populations and recruitment of warm-affinity species. We found differences in coral community structure over time, driven primarily by a fourfold increase of one local species, Plesiastrea versipora, rather than recruitment of warm-affinity species. Coral populations became strongly dominated by small size classes, indicative of recent increased recruitment or recruit survival. These changes were likely facilitated by competitive release of corals from dominant temperate seaweeds, which perished during the heatwaves, rather than driven by direct temperature effects. Overall, as corals are inherently warm-water taxa not commonly associated with seaweed-dominated temperate reefs, these findings are consistent with a net tropicalisation. Our study draws attention to processes other than gradual warming that also influence the trajectory of temperate reefs in a changing ocean.

  8. Wave transformation across coral reefs under changing sea levels

    Science.gov (United States)

    Harris, Daniel; Power, Hannah; Vila-Conejo, Ana; Webster, Jody

    2015-04-01

    The transformation of swell waves from deep water across reef flats is the primary process regulating energy regimes in coral reef systems. Coral reefs are effective barriers removing up to 99% of wave energy during breaking and propagation across reef flats. Consequently back-reef environments are often considered low energy with only limited sediment transport and geomorphic change during modal conditions. Coral reefs, and specifically reef flats, therefore provide important protection to tropical coastlines from coastal erosion and recession. However, changes in sea level could lead to significant changes in the dissipation of swell wave energy in coral reef systems with wave heights dependent on the depth over the reef flat. This suggests that a rise in sea level would also lead to significantly higher energy conditions exacerbating the transgressive effects of sea level rise on tropical beaches and reef islands. This study examines the potential implications of different sea level scenarios on the transformation of waves across the windward reef flats of One Tree Reef, southern Great Barrier Reef. Waves were measured on the reef flats and back-reef sand apron of One Tree Reef. A one-dimensional wave model was calibrated and used to investigate wave processes on the reef flats under different mean sea level (MSL) scenarios (present MSL, +1 m MSL, and +2 m MSL). These scenarios represent both potential future sea level states and also the paleo sea level of the late Holocene in the southern Great Barrier Reef. Wave heights were shown to increase under sea level rise, with greater wave induced orbital velocities affecting the bed under higher sea levels. In general waves were more likely to entrain and transport sediment both on the reef flat and in the back reef environment under higher sea levels which has implications for not only forecasted climate change scenarios but also for interpreting geological changes during the late Holocene when sea levels were 1

  9. Benthic buffers and boosters of ocean acidification on coral reefs

    Directory of Open Access Journals (Sweden)

    K. R. N. Anthony

    2013-07-01

    Full Text Available Ocean acidification is a threat to marine ecosystems globally. In shallow-water systems, however, ocean acidification can be masked by benthic carbon fluxes, depending on community composition, seawater residence time, and the magnitude and balance of net community production (NCP and calcification (NCC. Here, we examine how six benthic groups from a coral reef environment on Heron Reef (Great Barrier Reef, Australia contribute to changes in the seawater aragonite saturation state (Ωa. Results of flume studies using intact reef habitats (1.2 m by 0.4 m, showed a hierarchy of responses across groups, depending on CO2 level, time of day and water flow. At low CO2 (350–450 μatm, macroalgae (Chnoospora implexa, turfs and sand elevated Ωa of the flume water by around 0.10 to 1.20 h−1 – normalised to contributions from 1 m2 of benthos to a 1 m deep water column. The rate of Ωa increase in these groups was doubled under acidification (560–700 μatm and high flow (35 compared to 8 cm s−1. In contrast, branching corals (Acropora aspera increased Ωa by 0.25 h−1 at ambient CO2 (350–450 μatm during the day, but reduced Ωa under acidification and high flow. Nighttime changes in Ωa by corals were highly negative (0.6–0.8 h−1 and exacerbated by acidification. Calcifying macroalgae (Halimeda spp. raised Ωa by day (by around 0.13 h−1, but lowered Ωa by a similar or higher amount at night. Analyses of carbon flux contributions from benthic communities with four different compositions to the reef water carbon chemistry across Heron Reef flat and lagoon indicated that the net lowering of Ωa by coral-dominated areas can to some extent be countered by long water-residence times in neighbouring areas dominated by turfs, macroalgae and carbonate sand.

  10. The DNA of coral reef biodiversity: predicting and protecting genetic diversity of reef assemblages.

    Science.gov (United States)

    Selkoe, Kimberly A; Gaggiotti, Oscar E; Treml, Eric A; Wren, Johanna L K; Donovan, Mary K; Toonen, Robert J

    2016-04-27

    Conservation of ecological communities requires deepening our understanding of genetic diversity patterns and drivers at community-wide scales. Here, we use seascape genetic analysis of a diversity metric, allelic richness (AR), for 47 reef species sampled across 13 Hawaiian Islands to empirically demonstrate that large reefs high in coral cover harbour the greatest genetic diversity on average. We found that a species's life history (e.g. depth range and herbivory) mediates response of genetic diversity to seascape drivers in logical ways. Furthermore, a metric of combined multi-species AR showed strong coupling to species richness and habitat area, quality and stability that few species showed individually. We hypothesize that macro-ecological forces and species interactions, by mediating species turnover and occupancy (and thus a site's mean effective population size), influence the aggregate genetic diversity of a site, potentially allowing it to behave as an apparent emergent trait that is shaped by the dominant seascape drivers. The results highlight inherent feedbacks between ecology and genetics, raise concern that genetic resilience of entire reef communities is compromised by factors that reduce coral cover or available habitat, including thermal stress, and provide a foundation for new strategies for monitoring and preserving biodiversity of entire reef ecosystems.

  11. Sediment and turbidity associated with offshore dredging increase coral disease prevalence on nearby reefs.

    Directory of Open Access Journals (Sweden)

    F Joseph Pollock

    Full Text Available In recent decades, coral reef ecosystems have declined to the extent that reefs are now threatened globally. While many water quality parameters have been proposed to contribute to reef declines, little evidence exists conclusively linking specific water quality parameters with increased disease prevalence in situ. Here we report evidence from in situ coral health surveys confirming that chronic exposure to dredging-associated sediment plumes significantly increase the prevalence of white syndromes, a devastating group of globally important coral diseases. Coral health surveys were conducted along a dredging-associated sediment plume gradient to assess the relationship between sedimentation, turbidity and coral health. Reefs exposed to the highest number of days under the sediment plume (296 to 347 days had two-fold higher levels of disease, largely driven by a 2.5-fold increase in white syndromes, and a six-fold increase in other signs of compromised coral health relative to reefs with little or no plume exposure (0 to 9 days. Multivariate modeling and ordination incorporating sediment exposure level, coral community composition and cover, predation and multiple thermal stress indices provided further confirmation that sediment plume exposure level was the main driver of elevated disease and other compromised coral health indicators. This study provides the first evidence linking dredging-associated sedimentation and turbidity with elevated coral disease prevalence in situ. Our results may help to explain observed increases in global coral disease prevalence in recent decades and suggest that minimizing sedimentation and turbidity associated with coastal development will provide an important management tool for controlling coral disease epizootics.

  12. Coral reef management and conservation in light of rapidly evolving ecological paradigms.

    Science.gov (United States)

    Mumby, Peter J; Steneck, Robert S

    2008-10-01

    The decline of many coral reef ecosystems in recent decades surprised experienced managers and researchers. It shattered old paradigms that these diverse ecosystems are spatially uniform and temporally stable on the scale of millennia. We now see reefs as heterogeneous, fragile, globally stressed ecosystems structured by strong positive or negative feedback processes. We review the causes and consequences of reef decline and ask whether management practices are addressing the problem at appropriate scales. We conclude that both science and management are currently failing to address the comanagement of extractive activities and ecological processes that drive ecosystems (e.g. productivity and herbivory). Most reef conservation efforts are directed toward reserve implementation, but new approaches are needed to sustain ecosystem function in exploited areas.

  13. Acanthaster: effect on coral reef growth in panama.

    Science.gov (United States)

    Glynn, P W

    1973-05-04

    Analysis of data on coral abundance and growth, and the population size (26 individuals per hectare) and feeding rate of Acanthaster indicates that Pocillopora reefs on the Pacific coast of Panama are undergoing vigorous growth in the presence of this predator. Prediction of the effects of a population increase in Acanthaster to plague proportions (2.5 times that presently observed) suggests that reefs could still maintain a positive growth. However, Acanthaster at ten times the present population density would lead to rapid destruction of reefs. It is argued that coral destruction due to Acanthaster represents only one of several factors affecting coral reef progression.

  14. 76 FR 38618 - Proposed Information Collection; Comment Request; Coral Reef Conservation Program Survey

    Science.gov (United States)

    2011-07-01

    ... United States (U.S.) jurisdictions containing coral reefs. Specifically, NOAA is seeking information on... collection of social and economic data related to the communities affected by coral reef conservation programs. The Coral Reef Conservation Program (CRCP), developed under the authority of the Coral Reef...

  15. Conservation Planning for Coral Reefs Accounting for Climate Warming Disturbances.

    Directory of Open Access Journals (Sweden)

    Rafael A Magris

    Full Text Available Incorporating warming disturbances into the design of marine protected areas (MPAs is fundamental to developing appropriate conservation actions that confer coral reef resilience. We propose an MPA design approach that includes spatially- and temporally-varying sea-surface temperature (SST data, integrating both observed (1985-2009 and projected (2010-2099 time-series. We derived indices of acute (time under reduced ecosystem function following short-term events and chronic thermal stress (rate of warming and combined them to delineate thermal-stress regimes. Coral reefs located on the Brazilian coast were used as a case study because they are considered a conservation priority in the southwestern Atlantic Ocean. We show that all coral reef areas in Brazil have experienced and are projected to continue to experience chronic warming, while acute events are expected to increase in frequency and intensity. We formulated quantitative conservation objectives for regimes of thermal stress. Based on these objectives, we then evaluated if/how they are achieved in existing Brazilian MPAs and identified priority areas where additional protection would reinforce resilience. Our results show that, although the current system of MPAs incorporates locations within some of our thermal-stress regimes, historical and future thermal refugia along the central coast are completely unprotected. Our approach is applicable to other marine ecosystems and adds to previous marine planning for climate change in two ways: (i by demonstrating how to spatially configure MPAs that meet conservation objectives for warming disturbance using spatially- and temporally-explicit data; and (ii by strategically allocating different forms of spatial management (MPA types intended to mitigate warming impacts and also enhance future resistance to climate warming.

  16. Conservation Planning for Coral Reefs Accounting for Climate Warming Disturbances.

    Science.gov (United States)

    Magris, Rafael A; Heron, Scott F; Pressey, Robert L

    2015-01-01

    Incorporating warming disturbances into the design of marine protected areas (MPAs) is fundamental to developing appropriate conservation actions that confer coral reef resilience. We propose an MPA design approach that includes spatially- and temporally-varying sea-surface temperature (SST) data, integrating both observed (1985-2009) and projected (2010-2099) time-series. We derived indices of acute (time under reduced ecosystem function following short-term events) and chronic thermal stress (rate of warming) and combined them to delineate thermal-stress regimes. Coral reefs located on the Brazilian coast were used as a case study because they are considered a conservation priority in the southwestern Atlantic Ocean. We show that all coral reef areas in Brazil have experienced and are projected to continue to experience chronic warming, while acute events are expected to increase in frequency and intensity. We formulated quantitative conservation objectives for regimes of thermal stress. Based on these objectives, we then evaluated if/how they are achieved in existing Brazilian MPAs and identified priority areas where additional protection would reinforce resilience. Our results show that, although the current system of MPAs incorporates locations within some of our thermal-stress regimes, historical and future thermal refugia along the central coast are completely unprotected. Our approach is applicable to other marine ecosystems and adds to previous marine planning for climate change in two ways: (i) by demonstrating how to spatially configure MPAs that meet conservation objectives for warming disturbance using spatially- and temporally-explicit data; and (ii) by strategically allocating different forms of spatial management (MPA types) intended to mitigate warming impacts and also enhance future resistance to climate warming.

  17. Conservation Planning for Coral Reefs Accounting for Climate Warming Disturbances

    Science.gov (United States)

    Magris, Rafael A.; Heron, Scott F.; Pressey, Robert L.

    2015-01-01

    Incorporating warming disturbances into the design of marine protected areas (MPAs) is fundamental to developing appropriate conservation actions that confer coral reef resilience. We propose an MPA design approach that includes spatially- and temporally-varying sea-surface temperature (SST) data, integrating both observed (1985–2009) and projected (2010–2099) time-series. We derived indices of acute (time under reduced ecosystem function following short-term events) and chronic thermal stress (rate of warming) and combined them to delineate thermal-stress regimes. Coral reefs located on the Brazilian coast were used as a case study because they are considered a conservation priority in the southwestern Atlantic Ocean. We show that all coral reef areas in Brazil have experienced and are projected to continue to experience chronic warming, while acute events are expected to increase in frequency and intensity. We formulated quantitative conservation objectives for regimes of thermal stress. Based on these objectives, we then evaluated if/how they are achieved in existing Brazilian MPAs and identified priority areas where additional protection would reinforce resilience. Our results show that, although the current system of MPAs incorporates locations within some of our thermal-stress regimes, historical and future thermal refugia along the central coast are completely unprotected. Our approach is applicable to other marine ecosystems and adds to previous marine planning for climate change in two ways: (i) by demonstrating how to spatially configure MPAs that meet conservation objectives for warming disturbance using spatially- and temporally-explicit data; and (ii) by strategically allocating different forms of spatial management (MPA types) intended to mitigate warming impacts and also enhance future resistance to climate warming. PMID:26535586

  18. Arrecifes de Coral: Una Coleccion de Actividades en Espanol para Estudiantes de Escuela Intermedia (Coral Reefs: A Spanish Compilation of Activities for Middle School Students).

    Science.gov (United States)

    Walker, Sharon H.; Newton, R. Amanda; Ortiz, Alida

    This activity book for middle school students on coral reefs is divided into 10 sections. Section 1 is the introduction. Section 2 describes what coral reefs are while section 3 describes how coral reefs reproduce and grow. Section 4 describes where coral reefs are found, and section 5 describes life on a coral reef. Section 6 describes the…

  19. Deep reefs are not universal refuges: Reseeding potential varies among coral species

    Science.gov (United States)

    Bongaerts, Pim; Riginos, Cynthia; Brunner, Ramona; Englebert, Norbert; Smith, Struan R.; Hoegh-Guldberg, Ove

    2017-01-01

    Deep coral reefs (that is, mesophotic coral ecosystems) can act as refuges against major disturbances affecting shallow reefs. It has been proposed that, through the provision of coral propagules, such deep refuges may aid in shallow reef recovery; however, this “reseeding” hypothesis remains largely untested. We conducted a genome-wide assessment of two scleractinian coral species with contrasting reproductive modes, to assess the potential for connectivity between mesophotic (40 m) and shallow (12 m) depths on an isolated reef system in the Western Atlantic (Bermuda). To overcome the pervasive issue of endosymbiont contamination associated with de novo sequencing of corals, we used a novel subtraction reference approach. We have demonstrated that strong depth-associated selection has led to genome-wide divergence in the brooding species Agaricia fragilis (with divergence by depth exceeding divergence by location). Despite introgression from shallow into deep populations, a lack of first-generation migrants indicates that effective connectivity over ecological time scales is extremely limited for this species and thus precludes reseeding of shallow reefs from deep refuges. In contrast, no genetic structuring between depths (or locations) was observed for the broadcasting species Stephanocoenia intersepta, indicating substantial potential for vertical connectivity. Our findings demonstrate that vertical connectivity within the same reef system can differ greatly between species and that the reseeding potential of deep reefs in Bermuda may apply to only a small number of scleractinian species. Overall, we argue that the “deep reef refuge hypothesis” holds for individual coral species during episodic disturbances but should not be assumed as a broader ecosystem-wide phenomenon. PMID:28246645

  20. Deep reefs are not universal refuges: Reseeding potential varies among coral species.

    Science.gov (United States)

    Bongaerts, Pim; Riginos, Cynthia; Brunner, Ramona; Englebert, Norbert; Smith, Struan R; Hoegh-Guldberg, Ove

    2017-02-01

    Deep coral reefs (that is, mesophotic coral ecosystems) can act as refuges against major disturbances affecting shallow reefs. It has been proposed that, through the provision of coral propagules, such deep refuges may aid in shallow reef recovery; however, this "reseeding" hypothesis remains largely untested. We conducted a genome-wide assessment of two scleractinian coral species with contrasting reproductive modes, to assess the potential for connectivity between mesophotic (40 m) and shallow (12 m) depths on an isolated reef system in the Western Atlantic (Bermuda). To overcome the pervasive issue of endosymbiont contamination associated with de novo sequencing of corals, we used a novel subtraction reference approach. We have demonstrated that strong depth-associated selection has led to genome-wide divergence in the brooding species Agaricia fragilis (with divergence by depth exceeding divergence by location). Despite introgression from shallow into deep populations, a lack of first-generation migrants indicates that effective connectivity over ecological time scales is extremely limited for this species and thus precludes reseeding of shallow reefs from deep refuges. In contrast, no genetic structuring between depths (or locations) was observed for the broadcasting species Stephanocoenia intersepta, indicating substantial potential for vertical connectivity. Our findings demonstrate that vertical connectivity within the same reef system can differ greatly between species and that the reseeding potential of deep reefs in Bermuda may apply to only a small number of scleractinian species. Overall, we argue that the "deep reef refuge hypothesis" holds for individual coral species during episodic disturbances but should not be assumed as a broader ecosystem-wide phenomenon.

  1. Whole transcriptome analysis reveals changes in expression of immune-related genes during and after bleaching in a reef-building coral.

    Science.gov (United States)

    Pinzón, Jorge H; Kamel, Bishoy; Burge, Colleen A; Harvell, C Drew; Medina, Mónica; Weil, Ernesto; Mydlarz, Laura D

    2015-04-01

    Climate change is negatively affecting the stability of natural ecosystems, especially coral reefs. The dissociation of the symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral's resistance to stressors can help make informed predictions on the future of corals and coral reefs.

  2. Benthic N2 fixation in coral reefs and the potential effects of human-induced environmental change

    Science.gov (United States)

    Cardini, Ulisse; Bednarz, Vanessa N; Foster, Rachel A; Wild, Christian

    2014-01-01

    Tropical coral reefs are among the most productive and diverse ecosystems, despite being surrounded by ocean waters where nutrients are in short supply. Benthic dinitrogen (N2) fixation is a significant internal source of “new” nitrogen (N) in reef ecosystems, but related information appears to be sparse. Here, we review the current state (and gaps) of knowledge on N2 fixation associated with coral reef organisms and their ecosystems. By summarizing the existing literature, we show that benthic N2 fixation is an omnipresent process in tropical reef environments. Highest N2 fixation rates are detected in reef-associated cyanobacterial mats and sea grass meadows, clearly showing the significance of these functional groups, if present, to the input of new N in reef ecosystems. Nonetheless, key benthic organisms such as hard corals also importantly contribute to benthic N2 fixation in the reef. Given the usually high coral coverage of healthy reef systems, these results indicate that benthic symbiotic associations may be more important than previously thought. In fact, mutualisms between carbon (C) and N2 fixers have likely evolved that may enable reef communities to mitigate N limitation. We then explore the potential effects of the increasing human interferences on the process of benthic reef N2 fixation via changes in diazotrophic populations, enzymatic activities, or availability of benthic substrates favorable to these microorganisms. Current knowledge indicates positive effects of ocean acidification, warming, and deoxygenation and negative effects of increased ultraviolet radiation on the amount of N fixed in coral reefs. Eutrophication may either boost or suppress N2 fixation, depending on the nutrient becoming limiting. As N2 fixation appears to play a fundamental role in nutrient-limited reef ecosystems, these assumptions need to be expanded and confirmed by future research efforts addressing the knowledge gaps identified in this review. PMID:24967086

  3. Benthic N2 fixation in coral reefs and the potential effects of human-induced environmental change.

    Science.gov (United States)

    Cardini, Ulisse; Bednarz, Vanessa N; Foster, Rachel A; Wild, Christian

    2014-05-01

    Tropical coral reefs are among the most productive and diverse ecosystems, despite being surrounded by ocean waters where nutrients are in short supply. Benthic dinitrogen (N2) fixation is a significant internal source of "new" nitrogen (N) in reef ecosystems, but related information appears to be sparse. Here, we review the current state (and gaps) of knowledge on N2 fixation associated with coral reef organisms and their ecosystems. By summarizing the existing literature, we show that benthic N2 fixation is an omnipresent process in tropical reef environments. Highest N2 fixation rates are detected in reef-associated cyanobacterial mats and sea grass meadows, clearly showing the significance of these functional groups, if present, to the input of new N in reef ecosystems. Nonetheless, key benthic organisms such as hard corals also importantly contribute to benthic N2 fixation in the reef. Given the usually high coral coverage of healthy reef systems, these results indicate that benthic symbiotic associations may be more important than previously thought. In fact, mutualisms between carbon (C) and N2 fixers have likely evolved that may enable reef communities to mitigate N limitation. We then explore the potential effects of the increasing human interferences on the process of benthic reef N2 fixation via changes in diazotrophic populations, enzymatic activities, or availability of benthic substrates favorable to these microorganisms. Current knowledge indicates positive effects of ocean acidification, warming, and deoxygenation and negative effects of increased ultraviolet radiation on the amount of N fixed in coral reefs. Eutrophication may either boost or suppress N2 fixation, depending on the nutrient becoming limiting. As N2 fixation appears to play a fundamental role in nutrient-limited reef ecosystems, these assumptions need to be expanded and confirmed by future research efforts addressing the knowledge gaps identified in this review.

  4. Regional-scale scenario modeling for coral reefs: a decision support tool to inform management of a complex system.

    Science.gov (United States)

    Melbourne-Thomas, Jessica; Johnson, Craig R; Fung, Tak; Seymour, Robert M; Chérubin, Laurent M; Arias-González, J Ernesto; Fulton, Elizabeth A

    2011-06-01

    The worldwide decline of coral reefs threatens the livelihoods of coastal communities and puts at risk valuable ecosystem services provided by reefs. There is a pressing need for robust predictions of potential futures of coral reef and associated human systems under alternative management scenarios. Understanding and predicting the dynamics of coral reef systems at regional scales of tens to hundreds of kilometers is imperative, because reef systems are connected by physical and socioeconomic processes across regions and often across international boundaries. We present a spatially explicit regional-scale model of ecological dynamics for a general coral reef system. In designing our model as a tool for decision support, we gave precedence to portability and accessibility; the model can be parameterized for dissimilar coral reef systems in different parts of the world, and the model components and outputs are understandable for nonexperts. The model simulates local-scale dynamics, which are coupled across regions through larval connectivity between reefs. We validate our model using an instantiation for the Meso-American Reef system. The model realistically captures local and regional ecological dynamics and responds to external forcings in the form of harvesting, pollution, and physical damage (e.g., hurricanes, coral bleaching) to produce trajectories that largely fall within limits observed in the real system. Moreover, the model demonstrates behaviors that have relevance for management considerations. In particular, differences in larval supply between reef localities drive spatial variability in modeled reef community structure. Reef tracts for which recruitment is low are more vulnerable to natural disturbance and synergistic effects of anthropogenic stressors. Our approach provides a framework for projecting the likelihood of different reef futures at local to regional scales, with important applications for the management of complex coral reef systems.

  5. Strategic Science for Coral Ecosystems 2007-2011

    Science.gov (United States)

    ,

    2010-01-01

    Shallow and deep coral ecosystems are being imperiled by a combination of stressors. Climate change, unsustainable fishing practices, and disease are transforming coral communities at regional to global scales. At local levels, excessive amounts of sediments, nutrients, and contaminants are also impacting the many benefits that healthy coral ecosystems provide. This Plan, Strategic Science for Coral Ecosystems, describes the information needs of resource managers and summarizes current research being conducted by U.S. Geological Survey (USGS) scientists and partners. It outlines important research actions that need to be undertaken over the next five years to achieve more accurate forecasting of future conditions and develop more effective decision-support tools to adaptively manage coral ecosystems. The overarching outcome of this Plan, if fully implemented, would be in transferring relevant knowledge to decision-makers, enabling them to better protect and sustain coral ecosystem services. These services include sources of food, essential habitat for fisheries and protected species, protection of coastlines from wave damage and erosion, recreation, and cultural values for indigenous communities. The USGS has a long history of research and monitoring experience in studying ancient and living coral communities and serving many stakeholders. The research actions in this Plan build on the USGS legacy of conducting integrated multidisciplinary science to address complex environmental issues. This Plan is responsive to Federal legislation and authorities and a variety of external and internal drivers that include the President's Ocean Action Plan, the recommendations of the Coral Reef Task Force, the information needs of Bureaus in the Department of Interior, the USGS Bureau Science Strategy (USGS 2007) and the formal plans of several USGS Programs. To achieve this Plan's desired outcomes will require increased funding and more effective coordination and collaboration

  6. THE CONDITION OF CORAL REEFS IN SOUTH FLORIDA (2000) USING CORAL DISEASE AND BLEACHING AS INDICATORS

    Science.gov (United States)

    The destruction for coral reef habitats is occurring at unprecedented levels. Coral disease epizootics in the Southwestern Atlantic have lead to coral replacement by turf algae, prompting a call to classify some coral species as endangered. In addition, a massive bleaching event ...

  7. THE CONDITION OF CORAL REEFS IN SOUTH FLORIDA (2000) USING CORAL DISEASE AND BLEACHING AS INDICATORS

    Science.gov (United States)

    The destruction for coral reef habitats is occurring at unprecedented levels. Coral disease epizootics in the Southwestern Atlantic have lead to coral replacement by turf algae, prompting a call to classify some coral species as endangered. In addition, a massive bleaching event ...

  8. Coral community response to bleaching on a highly disturbed reef

    OpenAIRE

    Guest, J R; Low, J; Tun, K.; Wilson, B.; Ng, C.; D. Raingeard; Ulstrup, K. E.; Tanzil, J.T.I.; P. A. Todd; T. C. Toh; McDougald, D.; Chou, L.M.; Steinberg, P D

    2016-01-01

    While many studies of coral bleaching report on broad, regional scale responses, fewer examine variation in susceptibility among coral taxa and changes in community structure, before, during and after bleaching on individual reefs. Here we report in detail on the response to bleaching by a coral community on a highly disturbed reef site south of mainland Singapore before, during and after a major thermal anomaly in 2010. To estimate the capacity for resistance to thermal stress, we report on:...

  9. Coral community response to bleaching on a highly disturbed reef

    OpenAIRE

    Guest, J R; Low, J.; Tun, K.; B. Wilson; Ng, C.; Raingeard, D.; K. E. Ulstrup; Tanzil, J. T. I.; Todd, P.A.; Toh, T. C.; McDougald, D; Chou, L.M.; P. D. Steinberg

    2016-01-01

    While many studies of coral bleaching report on broad, regional scale responses, fewer examine variation in susceptibility among coral taxa and changes in community structure, before, during and after bleaching on individual reefs. Here we report in detail on the response to bleaching by a coral community on a highly disturbed reef site south of mainland Singapore before, during and after a major thermal anomaly in 2010. To estimate the capacity for resistance to thermal stress, we report on:...

  10. Coral recovery may not herald the return of fishes on damaged coral reefs

    KAUST Repository

    Bellwood, David R.

    2012-03-25

    The dynamic nature of coral reefs offers a rare opportunity to examine the response of ecosystems to disruption due to climate change. In 1998, the Great Barrier Reef experienced widespread coral bleaching and mortality. As a result, cryptobenthic fish assemblages underwent a dramatic phase-shift. Thirteen years, and up to 96 fish generations later, the cryptobenthic fish assemblage has not returned to its pre-bleach configuration. This is despite coral abundances returning to, or exceeding, pre-bleach values. The post-bleach fish assemblage exhibits no evidence of recovery. If these short-lived fish species are a model for their longer-lived counterparts, they suggest that (1) the full effects of the 1998 bleaching event on long-lived fish populations have yet to be seen, (2) it may take decades, or more, before recovery or regeneration of these long-lived species will begin, and (3) fish assemblages may not recover to their previous composition despite the return of corals. © 2012 Springer-Verlag.

  11. Coral recovery may not herald the return of fishes on damaged coral reefs.

    Science.gov (United States)

    Bellwood, David R; Baird, Andrew H; Depczynski, Martial; González-Cabello, Alonso; Hoey, Andrew S; Lefèvre, Carine D; Tanner, Jennifer K

    2012-10-01

    The dynamic nature of coral reefs offers a rare opportunity to examine the response of ecosystems to disruption due to climate change. In 1998, the Great Barrier Reef experienced widespread coral bleaching and mortality. As a result, cryptobenthic fish assemblages underwent a dramatic phase-shift. Thirteen years, and up to 96 fish generations later, the cryptobenthic fish assemblage has not returned to its pre-bleach configuration. This is despite coral abundances returning to, or exceeding, pre-bleach values. The post-bleach fish assemblage exhibits no evidence of recovery. If these short-lived fish species are a model for their longer-lived counterparts, they suggest that (1) the full effects of the 1998 bleaching event on long-lived fish populations have yet to be seen, (2) it may take decades, or more, before recovery or regeneration of these long-lived species will begin, and (3) fish assemblages may not recover to their previous composition despite the return of corals.

  12. The adaptation of coral reefs to climate change: Is the Red Queen being outpaced?

    Directory of Open Access Journals (Sweden)

    Ove Hoegh-Guldberg

    2012-06-01

    Full Text Available Coral reefs have enormous value in terms of biodiversity and the ecosystem goods and services that they provide to hundreds of millions of people around the world. These important ecosystems are facing rapidly increasing pressure from climate change, particularly ocean warming and acidification. A centrally important question is whether reef-building corals and the ecosystems they build will be able to acclimate, adapt, or migrate in response to rapid anthropogenic climate change. This issue is explored in the context of the current environmental change, which is largely unprecedented in rate and scale and which are exceeding the capacity of coral reef ecosystems to maintain their contribution to human well-being through evolutionary and ecological processes. On the balance of evidence, the ‘Red Queen’ (an analogy previously used by evolutionary biologists is clearly being ‘left in the dust’ with evolutionary processes that are largely unable to maintain the status quo of coral reef ecosystems under the current high rates of anthropogenic climate change.

  13. Relationships between structural complexity, coral traits, and reef fish assemblages

    Science.gov (United States)

    Darling, Emily S.; Graham, Nicholas A. J.; Januchowski-Hartley, Fraser A.; Nash, Kirsty L.; Pratchett, Morgan S.; Wilson, Shaun K.

    2017-06-01

    With the ongoing loss of coral cover and the associated flattening of reef architecture, understanding the links between coral habitat and reef fishes is of critical importance. Here, we investigate whether considering coral traits and functional diversity provides new insights into the relationship between structural complexity and reef fish communities, and whether coral traits and community composition can predict structural complexity. Across 157 sites in Seychelles, Maldives, the Chagos Archipelago, and Australia's Great Barrier Reef, we find that structural complexity and reef zone are the strongest and most consistent predictors of reef fish abundance, biomass, species richness, and trophic structure. However, coral traits, diversity, and life histories provided additional predictive power for models of reef fish assemblages, and were key drivers of structural complexity. Our findings highlight that reef complexity relies on living corals—with different traits and life histories—continuing to build carbonate skeletons, and that these nuanced relationships between coral assemblages and habitat complexity can affect the structure of reef fish assemblages. Seascape-level estimates of structural complexity are rapid and cost effective with important implications for the structure and function of fish assemblages, and should be incorporated into monitoring programs.

  14. Restocking herbivorous fish populations as a social-ecological restoration tool in coral reefs

    OpenAIRE

    Avigdor Abelson; Uri Obolski; Patrick Regoniel; Lilach Hadany

    2016-01-01

    The degradation of the world's coral reefs has aroused growing interest in ecological restoration as a countermeasure, which is widely criticized, mainly due to cost-effectiveness concerns. Here, we propose the restocking of herbivorous fish as a restoration tool, based on supply of young fish to degraded reefs, with the aims of: (1) Buildup of a critical fish biomass for basic ecosystem functions (e.g., grazing); (2) Increased fishing yields, which can sustain coastal communities, and conseq...

  15. Identifying multiple coral reef regimes and their drivers across the Hawaiian archipelago

    OpenAIRE

    Jouffray, Jean-Baptiste; Nyström, Magnus; Albert V. Norström; Williams, Ivor D.; Wedding , Lisa M.; John N Kittinger; Williams, Gareth J.

    2015-01-01

    Loss of coral reef resilience can lead to dramatic changes in benthic structure, often called regime shifts, which significantly alter ecosystem processes and functioning. In the face of global change an