Major Sources of Damage to Coral Reefs
Overfishing
Destructive Fishing Methods
Overfishing has caused a decline in populations of key reef species and
negatively impact coral reef ecosystem structure, function and economic value.
Destructive fishing methods are often used to stun fish for capture
for aquarium and live food trade.
Ex. Dynamite/Blast Fishing, Cyanide Fishing
Contact with Boats, Anchors and Divers
Coral Harvesting and Mining
Corals can be damaged or destroyed by shipwrecks, anchors and careless divers.
Corals can be damaged or destroyed by shipwrecks, anchors and careless divers.
Sedimentation and Pollution
Sewage
Sediment originating from soil disturbance or erosion harms corals by decreasing
light penetration into the water and reducing photosynthesis by zooxanthellae.
Excessive sediments can smother reefs.
Human sewage discharged from coastal developments can cause
diseases in corals, for example White Pox disease, caused by the bacterium
Serratia marscenens.
Chemical and nutrient runoff from coastal developments lowers water quality and can
stimulate excessive growth of macro algae at the expense of corals, resulting in
decreased biodiversity.
Sea Surface Temperature
Ocean Acidification
Elevated sea surface temperatures cause coral bleaching and increased damage
to reefs from breakage as storm frequency and intensity increase.
Ocean acidification decreases the availability of calcium carbonate
and the ability of corals to make and retain their exoskeletons
60
%
of Reefs Are Already
Seriously Damaged by
These Sources
SOURCE:
Burke et al, 2011
www.oceanhealthindex.org