Coral literature annotated bibliography
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| ). Global Change Biology, 17, (12). 3667-3678.
Changes in the carbonate chemistry of coral reef waters are driven by carbon fluxes from two sources: concentrations of CO2 in the atmospheric and source water, and the primary production/respiration and calcification/dissolution of the benthic community. Recent model analyses have shown that, depending on the composition of the reef community, the air-sea flux of CO2 driven by benthic community processes can exceed that due to increases in atmospheric CO2 (ocean acidification). We field test this model and examine the role of three key members of benthic reef communities in modifying the chemistry of the ocean source water: corals, macroalgae, and sand. Building on data from previous carbon flux studies along a reef-flat transect in Moorea (French Polynesia), we illustrate that the drawdown of total dissolved inorganic carbon (CT) due to photosynthesis and calcification of reef communities can exceed the draw down of total alkalinity (AT) due to calcification of corals and calcifying algae, leading to a net increase in aragonite saturation state (?a). We use the model to test how changes in atmospheric CO2 forcing and benthic community structure affect the overall calcification rates on the reef flat. Results show that between the preindustrial period and 1992, ocean acidification caused reef flat calcification rates to decline by an estimated 15%, but loss of coral cover caused calcification rates to decline by at least three times that amount. The results also show that the upstream-downstream patterns of carbonate chemistry were affected by the spatial patterns of benthic community structure. Knowlton, N. (2001). The future of coral reefs. PNAS, 98. Coral reefs, with their millions of species, have changed profoundly because of the effects of people, and will continue to do so for the foreseeable future. Reefs are subject to many of the same processes that affect other human-dominated ecosystems, but some special features merit emphasis: (i) Many dominant reef builders spawn eggs and sperm into the water column, where fertilization occurs. They are thus particularly vulnerable to Allee effects, including potential extinction associated with chronic reproductive failure. (ii) The corals likely to be most resistant to the effects of habitat degradation are small, short-lived “weedy” corals that have limited dispersal capabilities at the larval stage. Habitat degradation, together with habitat fragmentation, will therefore lead to the establishment of genetically isolated clusters of inbreeding corals. (iii) Increases in average sea temperatures by as little as 1°C, a likely result of global climate change, can cause coral “bleaching” (the breakdown of coral–algal symbiosis), changes in symbiont communities, and coral death. (iv) The activities of people near reefs increase both fishing pressure and nutrient inputs. In general, these processes favor more rapidly growing competitors, often fleshy seaweeds, and may also result in explosions of predator populations. (v) Combinations of stress appear to be associated with threshold responses and ecological surprises, including devastating pathogen outbreaks. (vi) The fossil record suggests that corals as a group are more likely to suffer extinctions than some of the groups that associate with them, whose habitat requirements may be less stringent. Knudby, A., .Brenning, A., & LeDrew, E. (2010). New approaches to modeling fish-habitat relationships. Ecological modelling, 221, 503-511. Ecologists often develop models that describe the relationship between faunal communities and their habitat. Coral reef fishes have been the focus of numerous such studies, which have used a wide range of statistical tools to answer an equally wide range of questions. Here, we apply a series of both conventional statistical techniques (linear and generalized additive regression models) and novel machine-learning techniques (the support vector machine and three ensemble techniques used with regression trees) to predict fish species richness, biomass, and diversity from a range of habitat variables. We compare the techniques in terms of their predictive performance, and we compare a subset of the models in terms of the influence each habitat variable has for the predictions. Prediction errors are estimated by cross-validation, and variable importance is assessed using permutations of individual variable values. For predictions of species richness and diversity the tree-based models generally and the random forest model specifically are superior (produce the lowest errors). These model types are all able to model both nonlinear and interaction effects. The linear model, unable to model either effect type, performs the worst (produces the highest errors). For predictions of biomass, the generalized additive model is superior, and the support vector machine performs the worst. Depth range, the difference between maximum and minimum water depth at a given site, is identified as the most important variable in the majority of models predicting the three fish community variables. Koenig, C., Coleman, F. C., Grimes, C. B., & et al (2000). Protection of fish spawning habitat for the conservation of warm-temperatate reef fish fisheries of shelf-edge reefs of Florida. Bulletin of Marine Science, 66, 593-616. We mapped and briefly describe the surficial geology of selected examples of shelf- edge reefs (50-120 m deep) of the southeastern United States, which are apparently de- rived from ancient Pleistocene shorelines and are intermittently distributed throughout the region. These reefs are ecologically significant because they support a diverse array of fish and invertebrate species, and they are the only aggregation spawning sites of gag (Mycteroperca microlepis), scamp (M. phenax), and other economically important reef fish. Our studies on the east Florida shelf in the Experimental Oculina Research Reserve show that extensive damage to the habitat-structuring coral Oculina varicosa has oc- curred in the past, apparently from trawling and dredging activities of the 1970s and later. On damaged or destroyed Oculina habitat, reef-fish abundance and diversity are low, whereas on intact habitat, reef-fish diversity is relatively high compared to historical diversity on the same site. The abundance and biomass of the economically important reef fish was much higher in the past than it is now, and spawning aggregations of gag and scamp have been lost or greatly reduced in size. On the west Florida shelf, fishers have concentrated on shelf-edge habitats for over 100 yrs, but fishing intensity increased dramatically in the 1980s. Those reefs are characterized by low abundance of economically important species. The degree and extent of habitat damage there is unknown. We recommend marine fishery reserves to protect habitat and for use in experimentally examining the potential production of unfished communities. Koh, E. G. & Sweatman, H. P. (2000). Chemical warfare among scleractinians: bioactive natural products from Tubastraea faulkneri Wells kill larvae of potential competitors. Journal of Experimental Marine Biology and Ecology, 251, 141-160. Competition for space among scleractinians by overgrowth, overtopping. Extracoelenteric digestion and the use of sweeper tentacles is well recognized, but another potential mode of competitive interaction, allelopathy, is largely uninvestigated. In this study, chemical extracts from Tubastraea faulkneri Wells were tested for deleterious effects on competent larvae of 11 other species of coral belonging to seven genera of four scleractinian families, Larvae exposed to extract concentrations from 10 to 500 ..g ml-' consistently suffered higher mortality than larvae in solvent controls. Larvae of Platygyra daedalea (Ellis and Solander) and Oxypora lacera (Verrill) wereth~rtl0s~sensiti~~,experiencing high. mortality even at the lowest extract concentration. The toxic compounds from T. faulkneri did not kill any conspecific larvae. Kohn, A. J. & Nybakken, J. W. (1975). Ecology of Conus on Eastern Indian Ocean fringing reefs: diversity of species and resource utilization. Marine Biology, 29,(3). 211-234. The most diverse assemblages of the genus Conus known occur on fringing coral reefs in Thailand and Indonesia. As many as 27 congeneric species of these gastropods inhabit a single reef; in all, we examined 1,350 individuals of 48 species. Several attributes of the populations we observed conform to expectations of a model of ecological characteristics of bench and reef Conus proposed by Kohn (1971a). Number of species (S) averaged 15, and species diversity (HPrime) averaged 2.3 in the most heterogeneous habitat type — topographically complex, subtidal reef platforms (Type III habitat). Both species richness and evenness of distribution of individuals among species contribute strongly to HPrime. Fewer congeners and greater numerical dominance by single species characterize more homogeneous habitats. On subtidal reef platforms with large areas of sand substrate and less coral limestone (Type I–III habitat), mean values were S=10, and HPrime=1.6. In the one intensively studied, truncated reef-limestone platform (Type II–III intermediate habitat), S=13 and HPrime=1.4. Summed population density of all Conus species in Type III and I–III habitats is similar (0.02 to 0.05 individuals /m2) and comparable to estimates from similar habitats elsewhere in the Indo-West Pacific region. Mean density (0.7/m2) and other population attributes in Type II–III habitat more closely resemble those of Type II than Type III habitats in general. We combined analysis of species diversity and other attributes of assemblages in habitats of different environmental complexity with analysis of microhabitat and food-resource utilization, in order to demonstrate the extent to which specialization on different resources occurs in assemblages differing in diversity and habitat type. In the habitats studied, co-occurring species of Conus specialized to a greater extent on different prey species than on different microhabitat patches, but degree of microhabitat specialization was greater than in similarly complex habitats with assemblages of lower diversity elsewhere in the Indo-West Pacific region. While most Conus species preyed primarily on a different species or higher taxon of polychaetes, diets are not more specialized or dissimilar than in similar habitats elsewhere. Degree of specialization on different prey is not correlated with Conus species diversity in the different types of habitats studied. The data lead to the conclusion that differential predation is as important — and differential microhabitat utilization is more important — in permitting coexistence of potentially competing congeners, compared with conditions in habitats of comparable heterogeneity that support fewer congeners farther from the center of the Indo-West Pacific region. Kokita, T. & Nakazono, A. (1998). Plasticity in the Mating System of the Longnose Filefish, Oxymonacanthus longirostris , in Relation to Mate Availability. Journal of Ethology, 16, 81-89. The mating system of the longnose filefish was examined on the coral reefs of Okinawa, Japan. Koop, K. (2001). The effect of nutrient enrichment on coral reef. Synthesis of results and conclusions. 42:91-120. Marine Pollution Bulletin, 42, 91-120. Coral reef degradation resulting from nutrient enrichment of coastal waters is of increasing global concern. Although effects of nutrients on coral reef organisms have been demonstrated in the laboratory, there is little direct evidence of nutrient effects on coral reef biota in situ. The ENCORE experiment investigated responses of coral reef organisms and processes to controlled additions of dissolved inorganic nitrogen (N) and/or phosphorus (P) on an offshore reef (One Tree Island) at the southern end of the Great Barrier Reef, Australia. A multi-disciplinary team assessed a variety of factors focusing on nutrient dynamics and biotic responses. A controlled and replicated experiment was conducted over two years using twelve small patch reefs ponded at low tide by a coral rim. Treatments included three control reefs (no nutrient addition) and three + N reefs (NH4Cl added), three + P reefs (KH2PO4 added), and three + N + P reefs. Nutrients were added as pulses at each low tide (ca twice per day) by remotely operated units. There were two phases of nutrient additions. During the initial, low-loading phase of the experiment nutrient pulses (mean dose = 11.5 microM NH4+; 2.3 microM PO4(-3)) rapidly declined, reaching near-background levels (mean = 0.9 microM NH4+; 0.5 microM PO4(-3)) within 2-3 h. A variety of biotic processes, assessed over a year during this initial nutrient loading phase, were not significantly affected, with the exception of coral reproduction, which was affected in all nutrient treatments. In Acropora longicyathus and A. aspera, fewer successfully developed embryos were formed, and in A. longicyathus fertilization rates and lipid levels decreased. In the second, high-loading, phase of ENCORE an increased nutrient dosage (mean dose = 36.2 microM NH4+; 5.1 microM PO4(-3)) declining to means of 11.3 microM NH4+ and 2.4 microM PO4(-3) at the end of low tide) was used for a further year, and a variety of significant biotic responses occurred. Knudby, A., .Brenning, A., & LeDrew, E. (2010). New approaches to modeling fish-habitat relationships. Ecological modelling, 221, 503-511. Ecologists often develop models that describe the relationship between faunal communities and their habitat. Coral reef fishes have been the focus of numerous such studies, which have used a wide range of statistical tools to answer an equally wide range of questions. Here, we apply a series of both conventional statistical techniques (linear and generalized additive regression models) and novel machine-learning techniques (the support vector machine and three ensemble techniques used with regression trees) to predict fish species richness, biomass, and diversity from a range of habitat variables. We compare the techniques in terms of their predictive performance, and we compare a subset of the models in terms of the influence each habitat variable has for the predictions. Prediction errors are estimated by cross-validation, and variable importance is assessed using permutations of individual variable values. For predictions of species richness and diversity the tree-based models generally and the random forest model specifically are superior (produce the lowest errors). These model types are all able to model both nonlinear and interaction effects. Kramer, P. A. & et al (2003). Status Of Coral Reefs In The Western Atlantic: Results Of Initial Surveys, Atlantic And Gulf Rapid Reef Assessment (Agrra) Program (Rep. No. 496). Washington, D.C.: Natural History Museum, Smithsonian. The global decline in coral reefs during the last decades has provoked the most serious concerns about these remarkable ecosystems. Were they owing to a single worldwide cause, like influenza, plague or HIV in humans, the focus of efforts to understand and remedy the situation would be clear. Instead, the causes of declines as well as the nature of reefs vary significantly from region to region and within regions. Thus the urgent need is to assess the condition of reefs regionally with directly comparable quantitative observations rather than anecdotal reports. This volume contains the initial reports and their synthesis of a new approach to assessing the regional condition of coral reefs in the Western Atlantic Ocean developed under the Atlantic and Gulf Rapid Reef Assessment (AGRRA) program. This new approach features rapid, multiscale assessments by teams of five-six trained observers for reefs of the Greater Caribbean, Gulf of Mexico and South Atlantic with the same method. Thus it becomes possible to assess many reefs spread over the entire region. Kraus, R. T., Hill, R. L., Rooker, J. R., & Dellapenna, T. M. (2006). Preliminary Characterization of a Mid-shelf Bank in the Northwestern Gulf of Mexico as Essential Habitat of Reef Fishes. Proceedings of the Gulf and Caribbean Fisheries Institute, No. 57, 621-632. The continental shelf of the northwestern Gulf of Mexico has many, widely scattered, high-relief, bathymetric features (or banks) that represent important naturally occurring aggregation areas for exploited fish species (especially snappers and groupers). While a few of these banks are protected and monitored as national marine sanctuaries (e.g., Flower Garden Banks), most are unprotected and poorly studied. Here, we present initial results of a study of one such bank, Sonnier Bank, where we are developing survey approaches with sidescan sonar, seismic devices, SCUBA, ROV (remotely operated vehicle), and fish traps. Sonnier Bank appears as a ring of topographic peaks, covering approximately 12.6 km super(2). At the shallowest depths (< 30 m) we have observed a diverse community of unexploited reef fishes associated with millepora coral and sponges. In this shallower environment, rock hind (Epinephelus adscensionis) were the dominant serranid. The deeper (45 to 60 m) bathymetric features of Sonnier Bank had the greatest numbers of exploited reef fish species. Sidescan and ROV surveys identified these areas as more gradually sloping with large pieces of rubble (1 to 4 m in diameter). Notable aggregations of vermilion snapper (Rhomboplites aurorubens) red snapper (Lutjanus campechanus) and gray snapper (L. griseus) were present, and yellowmouth grouper (Mycteroperca interstitialis) and graysby (Cephalopholis cruentata) were also observed. Our ongoing efforts include the calibration of a laser array for measuring distances with ROV video/ images, and comparisons of fish counts and measurements between divers and the ROV. The development of approaches with ROV may be an effective way to quantify and monitor commercially important snappers and groupers in these deeper, structurally-complex habitats. Krief, S., Hendy, E. J., Fine, M. L., & et al (2010). Physiological and isotopic responses of scleractinian corals to ocean acidification. Geochimica et Cosmochimica Acta, 74, 4988-5001. Uptake of anthropogenic CO2 by the oceans is altering seawater chemistry with potentially serious consequences for coral reef ecosystems due to the reduction of seawater pH and aragonite saturation state (Xarag). The objectives of this long-term study were to investigate the viability of two ecologically important reef-building coral species, massive Porites sp. and Stylophora pistillata, exposed to high pCO2 (or low pH) conditions and to observe possible changes in physiologically related parameters as well as skeletal isotopic composition. Fragments of Porites sp. and S. pistillata were kept for 6–14 months under controlled aquarium conditions characterized by normal and elevated pCO2 conditions, corresponding to pHT values of 8.09, 7.49, and 7.19, respectively. In contrast with shorter, and therefore more transient experiments, the long experimental timescale achieved in this study ensures complete equilibration and steady state with the experimental environment and guarantees that the data provide insights into viable and stably growing corals. During the experiments, all coral fragments survived and added new skeleton, even at seawater Xarag < 1, implying that the coral skeleton is formed by mechanisms under strong biological control. Measurements of boron (B), carbon (C), and oxygen (O) isotopic composition of skeleton, C isotopic composition of coral tissue and symbiont zooxanthellae, along with physiological data (such as skeletal growth, tissue biomass, zooxanthellae cell density, and chlorophyll concentration) allow for a direct comparison with corals living under normal conditions and sampled simultaneously. Skeletal growth and zooxanthellae density were found to decrease, whereas coral tissue biomass (measured as protein concentration) and zooxanthellae chlorophyll concentrations increased under high pCO2 (low pH) conditions. Both species showed similar trends of d11B depletion and d18O enrichment under reduced pH, whereas the d13C results imply species-specific metabolic response to high pCO2 conditions. Krupp, F. & Paulus, T. (1991). Territoriality and courtship behaviour in the coral reef fish {IPseudoanthias heemstrai} (Pisces: Serranidae) Rev.fr.Aquariol., 18, 43-46. Lacson, J. M. (1992). Minimal genetic variation among samples of six species of coral reef fishes collected at La Parguera, Puerto Rico, and Discovery Bay, Jamaica. Marine Biology, 112, 327-331. Lesser, M. P. (2000). Depth-dependent phopacclimatization to solar ultraviolet radiation in the Caribbean coral Montastraea faveolata. Marine Ecology-Progress Series, 192, 137-151. The importance of solar ultraviolet radiation (UVR, 290 to 400 nm), and UVB (290 to
Lewis, S. M. & Wainwright, P. C. (1985). Herbivore Abundance and Grazing Intensity on a Caribbean Coral Reef. Journal of Experimental Biology and Ecology, 87, 215-228. Significant differences among habitats in an experimental array of grazing across reef habitats does not appear to be simply explained by differences in reef topography.
The mass mortality of black sea urchins has had a detrimental effect on coral in the Caribbean due to an explosion of benthic algae that erode the coral's hard substrata which the urchins usually control. Lieske, E. &. M. R. (2002). Coral reef fishes 6594. (Rev. ed. ed.) Princeton, N.J.: Princeton University Press. Lipp, E. k., Jarrell, J. L., Griffin, D. W., & et al (2002). Preliminary evidence for human fecal contamination in corals of the Florida Keys, USA. Marine Pollution Bulletin, 44, 666-670. Corals and reef environments are under increased stress from anthropogenic activities, particularly those in the vicinity of heavily populated areas such as the Florida Keys. The potential adverse impacts of wastewater can affect both the environment and human health; however, because of the high decay rate of bacterial indicators in coral reef waters it has been difficult to document the presence of microbial contaminants and to assign risks in these environments. Here we show initial evidence that microorganisms associated with human feces are concentrated along the surface of coral heads relative to the overlying water column in the Florida Keys. Bacterial indicators (fecal coliform bacteria, enterococci or Clostridium perfringens) were detected in 66.7% of the coral surface microlayer (CSM) samples at levels between five and 1000 CFU/100 ml, but were found infrequently and at low numbers in the overlying water column ( < or = 2.5 CFU/100 ml). Similarly, enterovirus nucleic acid sequences, an indicator of human-specific waste, were detected in 93.3% of the CSM samples and only once in the water column by cell culture. Results show that coral mucus may accumulate enteric microorganisms in reef environments, and may indicate a risk to public and environmental health despite low indicator levels in the surrounding water.
less is known about the response of long-lived, sessile, benthic organisms to establishment of such reserves. Since antiquity, Mediterranean red coral (Corallium rubrum) has been harvested intensively for use in jewelry, and its distribution is currently smaller than its historical size throughout the Mediterranean Sea. To assess whether establishment of marine reserves is associated with a change in the size and number of red coral colonies that historically were not harvested sustainably, we analyzed temporal changes in mean colony diameter and density from 1992 to 2005 within red coral populations at different study sites in the Medes Islands Marine Reserve (established in 1992) and in adjacent unprotected areas. Moreover, we compared colony size in the Medes Islands Marine Reserve, where recreational diving is allowed and poaching has been observed after reserve establishment, with colony size in three other marine protected areas (Banyuls, Carryle- Rouet, and Scandola) with the enforced prohibition of fishing and diving. At the end of the study, the size of red coral colonies at all sampling sites in the Medes Islands was significantly smaller than predicted by growth models and smaller than those in marine protected areas without fishing and diving.
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