Scientists: Florida Keys coral reefs are already bleaching as water temperatures hit record highs

The coral reefs around the Florida Keys are losing their color early this summer because of record-high water temperatures. Federal scientists say they are already seeing some bleaching in the reefs. That doesn't usually happen until August. That doesn't mean the reefs are dead, but it is a sign that their health is endangered. Water temperatures are six degrees Fahrenheit warmer than normal. Even a sustained two-degree increase can harm the coral. The Keys have lost about 90% of their coral over the last 50 years. There are efforts underway to rebuild the reefs, but that will take 20 years.