Northern Madagascar has been identified by a group of marine scientists working for the Wildlife Conservation Society as a potential haven from climate change according to a paper recently published in the scientific journal Marine Ecology Progress Series.  The researchers analyzed seawater temperatures over the past 50 years and evaluated the coral reefs based on field surveys and found conditions for coral reef survival in the north were good. The authors note that because Madagascar extends from the tropics to temperate areas and the oceanographic conditions around the island represent a large diversity of ocean environments, it is a small microcosm of the global climate issues facing the tropics.

This study comes at a time when Madagascar has pledged to create an extensive network of marine and terrestrial marine parks that is expected to help preserve the unique biological diversity of the island. The country is working with international donors and conservation groups to develop a park system in a country where extreme poverty and reliance on natural resources has whittled away at the countries forests and coral reefs. The research was provoked by this unique island environment and to assist in the creation of these parks.

The authors suggest that northern Madagascar is also unique among Indian Ocean regions in having a slow seawater temperature rise and weaker climate oscillations. Climatic disturbances due to rising temperatures and strong oscillations, such as the El Niño, have been growing stronger since the 1970s and have been damaging temperature sensitive coral reefs. Ocean environments such as northern Madagascar were, however, among those least affected.

One finding of the study was contrary to a commonly held belief in the global change debate – that, as the climate warms, there will be a movement of species from the warm tropics to cooler latitudes. The investigators found that these more temperate and cooler coral reefs of the south, where there were once flourishing reefs, had been badly damaged by strong climate disturbances. Southern reefs had the fastest seawater temperatures rise and strongest oscillations and these temperature conditions combined with heavy fishing killed corals on a massive scale. The research shows the complexity of the responses to climate change and the need to carefully evaluate environments and priorities when creating parks.

The Western Indian Ocean Marine Science Association, CARE, the MacArthur Foundation, and the Wildlife Conservation Society in New York supported the research.

Full Citation: T.R. McClanahan, M. Ateweberhan, J. Omukoto, and L. Pearson. 2009. Recent seawater temperature histories, status, and predictions for Madagascar’s coral reefs. Mar Ecol Prog Ser 380: 117–128.