Top 5 Reasons Why Coral Communities Are Dying or Flourishing

The killing of too many plant-feeding fish leads to overgrowth of plants, which smother corals, threatening their survival

Relatively shallow (<27 metres), clear waters, allowing photosynthesis; deep-sea corals flourish in dark waters at 6,000 metres

Cuts out sunlight, giving rise to germs and disease; poisons corals directly, killing them
off quickly

Tropical and subtropical waters between 20 and 30°C; deep-sea corals survive without sunlight on underwater peaks called seamounts

Corals covered with sediment will succumb swiftly to tissue loss and death; Fungiid corals can actively shed sediment buildup by inflating and deflating rapidly

Increasing carbon dioxide levels changes water chemistry, preventing corals from building their skeletons; also slows down growth and rate of regeneration

Dredging-generated sediments smother corals

Require salinity between 34 and 37 parts per 1,000; they do well away from freshwater run-off

Overly warm waters cause coral bleaching, making them susceptible to disease, which can lead to large-scale reef die-off; stronger storms harm coral reefs, translating into less time for sensitive habitats to recover

Need we say more?