COLUMBUS, OhioThe future health of the world's coral reefs and the animals that depend on them relies in part on the ability of one tiny symbiotic sea creature to get fatand to be flexible about the type of algae it cooperates with.
In the first study of its kind, scientists at The Ohio State University discovered that coralstiny reef-forming animals that live symbiotically with algaeare better able to recover from yearly bouts of heat stress, called "bleaching," when they keep large energy reservesmostly as fatsocked away in their cells.
"We found that some coral are able to acclimatize to annual bleaching, while others actually become more susceptible to it over time," said Andra Grottoli, professor in the School of Earth Sciences at Ohio State. "We concluded that annual coral bleaching could cause a decline in coral diversity, and an overall decline of coral reefs worldwide."
The study, which appears in the July 9 online edition of Global Change Biology, indicates that some coral species will almost certainly decline with global climate change, while others that exhibit large fat storage and flexibility in the types of algae they partner with will stand a better chance of enduring repeated rounds of stress as oceans get hotter.
It also suggests that the most adaptable species would make good targets for conservation efforts because they are most likely to survive.
"If we conserve reefs that contain coral species with these survival traits, then we're hedging our bets that we might be able to preserve those reefs for an extra decade or two, buying them enough time to acclimatize to climate change," Grottoli said.
Corals are essentially colorless; the brilliant browns, yellows, and greens that we associate with them are actually the colors of algae living inside the corals' animal cells. That's why, when stressed coral dump most of the algae from their cells, their bodies appear pale, or "bleached."<
|Contact: Pam Frost Gorder|
Ohio State University