U.S. Commerce Secretary Norman Mineta announced four initiatives to help preserve coral reefs yesterday, after a monitoring group released a report saying that 27 percent of the world’s reefs were gone and that 70 percent would be dead by 2050. Mineta’s plan includes creating several “no anchoring” zones for large ships near reefs in the U.S. and moving ahead on research sponsored by the U.S. and Australia to study coral reef bleaching and the effects of global warming on reefs. The report by the Global Coral Reef Monitoring Network found that bleaching destroyed 16 percent of the world’s reefs in 1998 alone.