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The Challenges of a Putative Alien Coral in the Mediterranean Sea

Paper Reviewed
Rubio-Portillo, E., Vazquez-Luis, M., Valle, C., Izquierdo-Muņoz, A. and Ramos-Espla, A.A. 2014. Growth and bleaching of the coral Oculina patagonica under different environmental conditions in the western Mediterranean Sea. Marine Biology 161: 2333-2343.

The zooxanthellate scleractinian coral Oculina patagonica is said by Rubio-Portillo et al. (2014) to be "a species of uncertain, but likely temperate south-western Atlantic origin, which could have been accidentally transferred to the Mediterranean Sea by transoceanic transport," being first observed there in 1966 and currently spreading along the sea's basin by hitching rides on the region's intense maritime traffic.

Desirous to ascertain the ability of the Mediterranean's newest coral to cope with the different sets of environmental conditions thereby encountered, the five Spanish researchers studied - for a period of 18 months (June 2010 to December 2011) - coral growth rates of the species in two different environments: eutrophic and turbid (Alicante Harbor) and oligotrophic and transparent (Marine Protected Area of Tabarca), while additionally collecting data on sedimentation rates, chlorophyll a concentrations and organic matter contents, in order to assess coral growth rates and degree of bleaching in response to seawater temperature, and to investigate the role of light attenuation in the coral bleaching process. And what did they thereby learn?

"In conclusion," as Rubio-Portillo et al. write, their "between-environments comparison confirmed that O. patagonica has a broad tolerance to seawater temperature, irradiance and trophic water conditions, in addition to its ability to thrive through bleaching events, probably related to food availability, which could be contributing to the spread of this species along the Mediterranean coasts." Such findings demonstrate that Earth's corals appear to be a whole lot more resilient than what the world's climate alarmists make them out to be.

Posted 3 February 2015