Coral reef collapse spells danger for millions

The report on island coral reef fisheries reveals that over half (55%) of the 49 island countries reviewed were being exploited unsustainably. Fish landings are currently 64% higher than can be sustained. In order to support this level of exploitation, an additional 75,000 km2 of coral reef would be needed – an area 3.7 times greater than Australia’s Great Barrier Reef. These figures will nearly triple by 2050, given current human population growth projections.

Katie Newton, of the University of East Anglia’s School of Biological Sciences, undertook a survey of the landing catches of 49 island nations across the Pacific, Indian and Atlantic Oceans.

“Millions of people are dependent on coral reef fisheries. We are facing a global crisis among communities which have limited alternative livelihoods or major food sources,” she said.

“Coral reef ecologists have tended to focus on specific issues rather than the big picture of the resilience of these fisheries when faced with extensive over-exploitation. Scientists need to work hand in hand with development agencies to address this pressing situation.”

Team leader for the study, Dr Nick Dulvy, of Cefas, says: “Unchecked levels of over-exploitation can only lead to long-term social and economic hardship. Management methods to reduce dependence on reef fisheries are essential to prevent the collapse of these valuable ecosystems.

“Apart from over-fishing, sustainability could also be influenced by global warming impacts: the potential abandonment of atolls due to rising sea levels and the loss of reef productivity when temperature-induced bleaching kills coral. So it is likely that alternative livelihoods will be essential for many of those currently dependent on coral reef fisheries.”

The authors calculated the ecological footprint of the islands, where 1 equals resource consumption balancing sustainable reef production. One-third of the countries had unsustainable footprints (>1), and nearly half of the island nations were categorised as over-exploited or collapsed.