Read here. During the extreme warmth of the Super El Nino of 1998, over 40% of northern Tanzanian coral reefs suffered from bleaching. A multi-national group of researchers documented not only the recovery of the reefs, but their actual improvement.
"repeated surveys "indicate general stability of these reefs over time," and they state that "in the context of the high bleaching and mortality of western Indian Ocean reefs after 1998, the general stability and improvement of these reefs six to seven years after the largest ENSO in recent history indicates reefs with considerable resilience to climate change."
As for recommendations to protect reefs in the future:
"all countries need to implement local measures to protect their coral reefs, and not waste precious time thinking that they -- or even all nations acting in concert -- will ever be able to dictate the course of earth's climate over any foreseeable future timeframe. In addition, as we have repeatedly posited on our website, local environmental protection measures will almost surely enable earth's corals to better withstand the negative consequences of whatever global environmental pressures they may encounter in the future."
