Reuters: A survey of coral reefs off the Hawaiian island of Oahu has shown warm ocean waters recently contributed to a higher rate of coral bleaching than the state has seen in decades, sparking concerns about the ecosystem, a state official said on Tuesday. The findings from dives last week by researchers with the Hawaii Division of Aquatic Resources follows federal warnings of a possible large decline in coral cover in the archipelago this century due to climate change and warming oceans. Coral underpins...