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Gonzalez-Rivero, M, Bongaerts P, Beijbom O, Pizarro O, Friedman A, Rodriguez-Ramirez A, Upcroft B, Laffoley D, Kline D, Bailhache C, Vevers R, Hoegh-Guldberg O.  2014.  The Catlin Seaview Survey - kilometre-scale seascape assessment, and monitoring of coral reef ecosystems. Aquatic Conservation-Marine and Freshwater Ecosystems. 24:184-198.   10.1002/aqc.2505   AbstractWebsite

Marine ecosystems provide critically important goods and services to society, and hence their accelerated degradation underpins an urgent need to take rapid, ambitious and informed decisions regarding their conservation and management.The capacity, however, to generate the detailed field data required to inform conservation planning at appropriate scales is limited by time and resource consuming methods for collecting and analysing field data at the large scales required.The Catlin Seaview Survey', described here, introduces a novel framework for large-scale monitoring of coral reefs using high-definition underwater imagery collected using customized underwater vehicles in combination with computer vision and machine learning. This enables quantitative and geo-referenced outputs of coral reef features such as habitat types, benthic composition, and structural complexity (rugosity) to be generated across multiple kilometre-scale transects with a spatial resolution ranging from 2 to 6m(2).The novel application of technology described here has enormous potential to contribute to our understanding of coral reefs and associated impacts by underpinning management decisions with kilometre-scale measurements of reef health.Imagery datasets from an initial survey of 500km of seascape are freely available through an online tool called the Catlin Global Reef Record. Outputs from the image analysis using the technologies described here will be updated on the online repository as work progresses on each dataset.Case studies illustrate the utility of outputs as well as their potential to link to information from remote sensing. The potential implications of the innovative technologies on marine resource management and conservation are also discussed, along with the accuracy and efficiency of the methodologies deployed.10.1002/(ISSN)1099-0755 Copyright (c) 2014 John Wiley & Sons, Ltd.

Kline, DI, Kuntz NM, Breitbart M, Knowlton N, Rohwer F.  2006.  Role of elevated organic carbon levels and microbial activity in coral mortality. Marine Ecology-Progress Series. 314:119-125.   10.3354/meps314119   AbstractWebsite

Coral reefs are suffering a long-term global decline, yet the causes remain contentious. The role of poor water quality in this decline is particularly unclear, with most previous studies providing only weak correlations between elevated nutrient levels and coral mortality. Here we experimentally show that routinely measured components of water quality (nitrate, phosphate, ammonia) do not cause substantial coral mortality. In contrast, dissolved organic carbon (DOC), which is rarely measured on reefs, does. Elevated DOC levels also accelerate the growth rate of microbes living in the corals' surface mucopolysaccharide layer by an order of magnitude, suggesting that mortality occurs due to a disruption of the balance between the coral and its associated microbiota. We propose a model by which elevated DOC levels cause Caribbean reefs to shift further from coral to macroalgal dominance. Increasing DOC levels on coral reefs should be recognized as a threat and routinely monitored.

Casas, V, Kline DI, Wegley L, Yu YN, Breitbart M, Rohwer F.  2004.  Widespread association of a Rickettsiales-like bacterium with reef-building corals. Environmental Microbiology. 6:1137-1148.   10.1111/j.1462-2920.2004.00647.x   AbstractWebsite

White band disease type I (WBD I) has been a major cause of the dramatic decline of Acroporid coral populations throughout the Caribbean during the last two decades, yet the aetiological agent of this disease is unknown. In this study, the bacterial communities associated with both healthy and diseased Acropora species were compared by 16S rDNA analyses. The bacterial communities of both healthy and diseased Acropora spp. were dominated by a single ribotype with 90% identity to a bacterium in the order Rickettsiales. Screening by nested PCR specific to the coral-associated Rickettsiales 1 (CAR1) bacterium showed that this microbe was widespread in both healthy and diseased A. cervicornis and A. palmata corals from 'healthy' (i.e. low WBD I incidence) and 'stressed' reefs (i.e. high WBD I incidence). These results indicate that there were no dramatic changes in the composition of the microbial community associated with WBD I. CAR1 was also associated with non-Acroporid corals of the Caribbean, as well as with two Acroporid corals native to the Pacific. CAR1 was not present in the water column. This bacterium was also absent from preserved Caribbean Acroporid samples collected between 1937 and 1980 before the outbreak of WBD I. These results suggest CAR1 is a relatively new bacterial associate of Acroporids and that a non-bacterial pathogen might be the cause of WBD I.