Pollution

Scientists have identified pollution as one of the leading causes of coral reef degradation. This threat comes from a variety of sources.

For example, oil, gas and pesticide contamination poisons coral and marine life. Reefs are harmed when human, animal waste and/or fertilizer is dumped into the ocean or when river systems carry these pollutants to reef waters. These pollutants increase the level of nitrogen around coral reefs, causing an overgrowth of algae, which smothers reefs by cutting off their sunlight.

Trash also kills coral reef animals. Floating trash can cover reefs, blocking off sunlight that polyps need to survive. Turtles often mistake plastic bags for jellyfish and eat them. Plastic blocks the turtle's digestive tract, causing them to starve to death. Lost or discarded fishing nets - called "ghost nets" - can snag on reefs and strangle thousands of fish, sea turtles and marine mammals.

Pollution Overfishing Climate Change