Half the world's coral reefs may disappear

Up to half of the world's coral reefs may disappear by 2045 unless urgent measures are taken to protect them against environmental hazards, the World Conservation Union said.

The Swiss-based group called for the establishment of more protected marine areas to shelter the coral reefs from fishing and pollution.

The group said many reefs die due to"bleaching", where algae, which provide the coral with food, die because of rising temperatures.