Barnacles Respond to Climate Change
Coast of France and Spain

Decades of studying intertidal species reveal that they are especially sensitive to climate change.

The acorn barnacle, Semibalanus balanoides, struggles to reproduce in water warmer than 10°C. Since 1872, rising ocean temperatures have shifted the acorn barnacle’s range in France 300 km northward, where waters generally stay below 10°C. Half of this change has occurred in the last 30 years.

An isolated population does persist off the coast of northern Spain. Cold, deep waters rise to the ocean surface there. While global warming is pushing many intertidal species north, some populations survive where local conditions support them.

Researchers
David S. Wethey/Sarah A. Woodin (University of South Carolina)

Paper
Wethey, D. S. and S. A Woodin. Ecological hindcasting of biogeographic responses to climate change in the European intertidal zone. (Submitted to Hydrobiologica.)

Image Credits 
France and Spain, October 2004 (Blue Marble: Next Generation, satellite: NASA Terra/Aqua, sensor: MODIS)
Sea surface temperature February 2006 (NASA)
Acorn barnacle–Dr. Robert Zottoli

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