Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Is climate change likely to increase disease in corals?

08.05.2007
Coral reefs, among Earth’s richest ecosystems, traditionally teem with an abundance of life. But in recent years, corals have been dying in droves.

Scientists suspect a variety of factors, ranging from accidental damage from fishing activity to the effects of polluted runoff from land. One threat that appears to be growing dramatically in Australia’s famed Great Barrier Reef is white syndrome, a disease that is spreading rapidly, leaving stripes of dead corals like ribbons of death in its wake. In a new study published by PLoS Biology, John Bruno, Amy Melendy, and colleagues show that the interaction between anomalously high ocean temperatures and the extent of coral cover is likely to account for the occurrence of the disease.

Global warming has seemed a likely suspect for several reasons. Past epidemiological studies—across a broad range of life forms—have shown that stress, including the stress of changing environmental conditions, often increases disease susceptibility. As temperatures rise, pathogens can reproduce more quickly. The fact that coral diseases seem to spread faster in summer also provides support for the notion that warmer temperatures may be involved. The authors conducted a regional-scale longitudinal study of the hypothesized link between warm temperature deviations and the presence of white syndrome, considering the density of coral cover as an additional variable of interest. To quantify temperature fluctuations, the researchers used a high resolution dataset on ocean surface temperature provided by the United States National Oceanic and Atmospheric Association and the University of Miami. They used the dataset to calculate w eekly sea surface temperature anomalies (WSSTAs), instances in which temperature was higher by 1°C or more from mean records for that week, for 48 reefs within the Great Barrier Reef. To evaluate the extent of white syndrome and coral cover, the researchers used data collected by the Australian Institute of Marine Science Long-term Monitoring Program on 48 reefs from a 1,500-kilometer stretch of the Great Barrier Reef from 1998 to 2004 at a depth of six to nine meters. Divers counted the number of infected colonies on each reef. Coral cover, the amount of the bottom with living corals, was measured from videos taken of the reefs.

The researchers then evaluated the relationship between the occurrence of white syndrome and three variables: number of WSSTAs occurring during the previous 52 weeks, coral cover, and the interaction between the two. They found that the third variable showed a statistically significant correlation with number of white syndrome cases, indicating that the presence of both conditions (temperature anomalies and high coral cover) creates the conditions in which white syndrome outbreaks are most likely to occur. In other words, WSSTAs were a necessary but not sufficient condition for white syndrome outbreaks, whereas the combination of heat stress and a dense colony was deadly.

What does this mean for corals and the ecosystem they support? If global warming increases the incidence of warm temperature anomalies in tropical oceans the years ahead, these results suggest that corals in high-cover areas will be increasingly vulnerable to white disease. If the effect is large enough, the tightly woven web of life within coral reefs could begin to unravel, potentially transforming habitats that were once among the planet’s richest ecosystems into underwater wastelands. This strong evidence for a link among a warming ocean, coral density, and white syndrome provides a rich foundation for further work to understand the spread of coral disease in the Great Barrier Reef. It also provides valuable insights into marine epidemiology that could be of much value in investigating and potentially mitigating other devastating global warming-related disease outbreaks in the world’s vast and vulnerable oceans.

Citation: Bruno JF, Selig ER, Casey KS, Page CA, Willis BL, et al. (2007) Thermal stress and coral cover as drivers of coral disease outbreaks. PLoS Biol 5(6): e124. doi:10.1371/journal.pbio.0050124.

Andrew Hyde | alfa
Further information:
http://www.plosbiology.org
http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0050124

More articles from Ecology, The Environment and Conservation:

nachricht Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>