More about reefs

Most of the world's coral reefs are in trouble.

Over a decade ago scientists reported that some 10% of coral reefs had already been destroyed or degraded beyond likelihood of recovery.

Monitoring results from around the world in 1998 and 1999 indicated that less than 30% of coral reefs have completely healthy communities of corals, fish and other species.

Coral bleaching, (corals which are stressed can loose their zooxanthellae causing them to have a whitened or bleached appearance), in 1997 and 1998 had severe impacts.

Large parts of many reefs lost 90% of their live coral cover, including colonies as much as 1000 years old. In other areas over the past 30 years, similar damage has been caused by the coral-eating crown of thorns seastars.

Reefs grow very slowly, but are able to recover their extent and species diversity if ambient environmental conditions improve or remain constant.

The combined effect of direct human impacts, and natural threats to reefs, such as predation from Crown of Thorns seastars, outbreaks of disease and increasing frequency of coral bleaching and severe storms can however overwhelm the recovery capacity of many reef systems.

For many people this is a crisis calling for immediate action.


References: http://www.icran.org/peoplereefs-tenquestions.html