Hot and sick

Coral disease outbreaks have struck the healthiest sections of Australia's Great Barrier Reef, where for the first time researchers have conclusively linked disease severity and ocean temperature. Close living quarters among coral may make it easy for infection to spread, researchers have found.

"With this study, speculation about the impacts of global warming on the spread of infectious diseases among susceptible marine species has been brought to an end," [says] Don Rice, director of the [US] National Science Foundation Chemical Oceanography Program...

These findings may not seem new to everybody, but look to be based on original and thorough work. The conclusion of the study, Thermal Stress and Coral Cover as Drivers of Coral Disease Outbreaks by John F. Bruno et al. (PLoS Biology, 8 May), notes:

Warm temperature anomalies and coral cover are clearly important drivers of [the emergent disease] white syndrome on the GBR. No previous study has demonstrated a link between ocean temperature and coral disease dynamics, especially at regional spatial scales.

[see also Putting the Heat on Coral by Phil Berardelli]