Coral Reefs Formation and Threats

Corals

• Corals are tiny animals called polyps that live in tropical regions close to the sea floor in warm, shallow waters.
• Corals secrete calcium carbonate, which consolidates into rocks, eventually forming ridge-like structures of coral reefs on the sea floor over time.

Formation of Coral Reefs

• A polyp attaches itself to the sea floor and divides into multiple clones, starting the formation of a reef.
• The hard, limestone skeletons (calicles) at the base of the polyps connect to one another, creating a colony that acts as a single organism.
• The colonies grow over several years and join with other colonies to become reefs.

Threats to Coral Reefs

• Climate change, global warming, human exploitation, and natural predators are causing a rapid decline of coral reefs.
• Coral bleaching occurs when there is an increase in the temperature of ocean water.
• Oil spills and nitrogen run-off from farms make corals vulnerable to bleaching.

The Great Barrier Reef

• The Great Barrier Reef is the world's largest coral reef, located off the northeast coast of Australia.
• It has over 400 types of corals, 1500 species of fish, and 4000 varieties of snails, molluscs, and octopuses.
• The reef is home to rare species of sea cows and large green turtles.
• The reef is a long, narrow, mostly submerged coral formation, extending about 2000 km, lying parallel to the shoreline.

This quiz covers the formation of coral reefs, the biology of corals, and the threats they face. Learn about the importance of coral reefs and how they are affected by environmental changes.