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Oral Session June 30 (Wed) 124 Oral 4-2-A Diagnostic Monitoring & Assessment of Coral Reefs: Studies from Around the World 10Th ICRS

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Oral Session June 30 (Wed) 124 Oral 4-2-A Diagnostic Monitoring & Assessment of Coral Reefs: Studies from Around the World 10Th ICRS Oral Session June 30 (Wed) 124 Oral 4-2-A Diagnostic Monitoring & Assessment of Coral Reefs: Studies from Around the World 10th ICRS Response Specific Metrics for a Coral Reef Index of Biotic Integrity: New Cellular Stress Responses and their Application as Early Warning Signals Diagnostic Cellular Assays and Future Research Directions of Coral Bleaching: A Great Barrier Reef Test Case Stephen C JAMESON*, Craig A DOWNS, Kennard W POTTS Carolyn R SMITH*, Sophie G DOVE, Madeleine VAN OPPEN, Ove HOEGH- 4254 Hungry Run Road, The Plains, VA 20198-1715 United States of America GULDBERG [email protected] 35 Jacaranda Crescent, Annandale QLD 4814, Australia [email protected] In our continuing effort to create a new paradigm for coral reef monitoring and assessment (i.e., one with early warning and diagnostic capabilities) we provide Global climate change and rising sea temperatures are likely to increase the new information on response specific cellular assays for a coral reef index of frequency and severity of mass coral bleaching events adding significantly to biotic integrity (IBI). These assays not only have the power to determine the current decline of coral reef ecosystems. It is vital that we are able to specifically WHAT is causing the change in coral reef systems but can also differentiate reef decline due to elevated sea temperatures from that due to provide vital insight into HOW the stressor is operating within the metabolism direct anthropogenic effects such as coastal run-off and point source pollution. of the target organism. Cellular assays fit within the Individual Condition Monitoring of cellular levels of key proteins such as heat shock proteins (HSPs) category of the framework for a coral reef IBI and can potentially have and antioxidant enzymes (such as copper zinc superoxide dismutase) has been relevance to all the attributes within this category. While potentially very proposed as a method for both predicting the occurrence of coral bleaching powerful, cellular assays should not be used as the only metric(s) in biological events and diagnosing their cause. This study tested this cellular biomarker monitoring and assessment. We discuss the suggested number of metrics, from monitoring approach as an early warning signal for coral bleaching in a each metric type, that should be included in a well-constructed IBI to reflect the common Great Barrier Reef (GBR) coral species namely Acropora millepora. multiple dimensions of biological systems. Not using this multi-dimensional Both laboratory heating and field based monitoring were carried out. Field strategy can result in flawed assessments and poor management decisions. samples were taken regularly leading up to and throughout the 2002 bleaching Finally, we show what cellular assays work now for coral reefs, discuss event on the GBR. Little change in the cellular levels of several key biomarkers research pitfalls to avoid and outline promising areas for future cellular assay (eg HSP60, glutathione peroxidase, ubiquitin and others) were detected for this research for diagnostic coral reef monitoring and assessment. hard coral species during laboratory heating or in the field during a natural bleaching event. This contrasts the results of published experimental studies on both Montastrea faveolata and Goniastrea aspera and suggests the potential for significant differences in the strength of cellular stress responses between coral species. Field monitoring revealed an apparent peak in biomarker levels around the time of annual spawning. This peak, however, occurred in the lead up to both bleaching and non-bleaching summers. Such a result highlights the requirement for cellular biomarker data to be cautiously interpreted in the context of seasonal physiological status. Integrating Marine Biotechnology into Coral Reef Health Assessment Detecting Coral Response to Environmental Stress in the Field Using a Cheryl M WOODLEY, John C HALAS*, Pamela HALLOCK-MULLER, John E cDNA Array FAUTH, Craig A DOWNS, Elizabeth M FISHER, Samantha L RYAN, Judith Sara E BROGDON*, Terry W SNELL, Michael B MORGAN HALAS 311 Ferst Drive, Atlanta, Georgia 30332 United States of America Hollings Marine Laboratory, 331 Ft Johnson Rd., Charleston, SC 29412 United [email protected] States of America Common stressors associated with declining coral communities include [email protected] variations in temperature, changes in salinity, suspended sediment, and Increasing anthropogenic impacts threaten the health and stability of coral reef exposure to UV radiation. There is an urgent need for biomarkers that can be ecosystems, yet the mechanisms underlying these problems remain largely used to diagnose the type of stressors impacting natural populations of corals. unknown. Current methods of assessing ecosystem health focus on abiotic and Our work has focused on developing genetic biomarkers of stress for the reef ecological components because well-developed procedures are available to building coral Montastrea faveolata. Using a variety of techniques, we detect contaminants and monitor the responses of individuals, populations and developed a cDNA array consisting of thirty-two gene probes. The known communities. However, technologies that can reveal the molecular and cellular function of these genes allows changes in their expression to be associated with physiological processes that govern how organisms respond to environmental stressors (which is the critical link between environmental contaminants and thermal stress, oxidative stress, and sediment stress among others. We used this whole organisms) are now available. To aid in establishing the link between stress gene array to monitor corals in the Florida Keys over a seven-month stressor and organism response, we conducted a study in the Florida Keys that period from April to October in 2001. Five replicate samples of M. faveolata integrated new biotechnologies, able to assess processes occurring at the were collected biweekly from East Turtle Shoals near Long Key and processed molecular and cellular level of coral (Montastraea annularis), turtle grass on site using Trizol to inhibit RNA degradation. Several months later, RNA was (Thalassia testudinum), calcareous green algae (Halimeda opuntia), extracted, labeled with a chemiluminescent tag, and hybridized to the cDNA corallivorous snails (Coralliophila abbreviata), bicolor damselfish (Stegastes partitus) and white grunts (Haemulon plumieri,) with well-established methods array. Stress gene expression by M. faveolata was evident in late May, June, for assessing standard parameters of coral reef health. The study region was July, August, and September. Strongly up-regulated genes included carbonic particularly relevant in that it included areas of extensive coral degradation anhydrase, thioredoxin, polyubiquitin, and an uncharacterized stress gene. associated with frequent and intense ocean warming events (El Nino) and Expression of some ribosomal genes also co-varied with these stress genes. By suspected local stressors. Our goals were to 1) use a new biotechnology, correlating gene expression patterns with environmental parameters we should Environmental Cellular Diagnostics, to characterize the health of a coral reef be able to track the timing of stress events and to diagnose the main classes of ecosystem in the Florida Keys; 2) verify the technology can detect and characterize subtle and chronic effects of environmental stressors on this stressors impacting natural populations of corals. ecosystem; 3) determine if point-source pollutants or global climate changes (e.g., increased ocean temperatures or UV-B radiation) are stressing coral reef ecosystems; 4) compare the precision, sensitivity and prognostic capabilities of the technology to those of traditional measures of ecosystem health, and 5) encourage the participation and understanding of the general public and scientific, industrial, and managerial communities in using marine biotechnologies to assess and manage the health of coral reef ecosystems. 125 10th ICRS Diagnostic Monitoring & Assessment of Coral Reefs: Studies from Around the World Oral 4-2-A A Framework to Identify Ecological Change and its Causes: Effects of Terrestrial Run-off on Coral Reefs Katharina E FABRICIUS*, Glenn DE’ATH PMB No. 3, Townsville MC, Qld 4810, Australia [email protected] Many inshore reefs of the Great Barrier Reef (GBR) are exposed to terrestrial run-off from agriculture. However, detecting ecosystem change and attributing it to the increasing river discharges of nutrients, sediments and pesticides is difficult, both philosophically and practically, and in this case complicated by the large spatial scale, presence of additional disturbances (bleaching, crown- of-thorns starfish) and lack of historic data. Nevertheless, ecosystem management depends on early detection of change and identification of factors causing such change, as well as a clear and transparent communication of scientific results to the broader public. We developed and applied a framework to address these problems. The framework is based on epidemiological causal criteria that are both scientifically rigorous and understood by non-specialists, and on improved methods of statistical estimation. Ecological attributes, namely benthos cover, octocoral richness, and community structure, were used to discriminate between potential causes of change. These attributes were surveyed along water quality gradients in two regions; one that receives river flood plumes from
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