This The Guardian article discusses how the Great Barrier Reef hard coral cover is close to record lows. Coral bleaching, crown-of-thorns starfish and cyclones reduced coverage to 10% to 30% over past five years.
Hard coral cover on the Great Barrier Reef is near record lows in its northern stretch and in decline in the south, surveys by government scientists have found.
A report card by the government’s Australian Institute of Marine Science says hard coral cover in the northern region above Cooktown is at 14% – a slight increase on last year but close to the lowest since monitoring began in 1985.
This Yale Environment 360 article discusses how, as Ocean Temperatures Rise, Corals Are Steadily Moving Poleward. Rising ocean temperatures are increasingly causing coral reefs to shift away from the equator into more temperate waters. Over the past 40 years, the number of young corals has declined by 85 percent on tropical reefs, while at the same time doubling in cooler regions, according to a recent study published in the journal Marine Ecology Progress Series.