Why is coral reef important

You may have heard that coral reefs are being threatened by human activity. For instance, the Fight for the Reef campaign aims to raise awareness about how proposed increases in shipping traffic and development of large ports near the Great Barrier Reef would negatively impact the largest coral reef system in the world. Corals are related to jellyfish and anemones, and most species are colonial. Scleractinian corals, or "hard corals" secrete a calcium carbonate skeleton; the living animal is typically just a thin layer of tissue atop the stony skeleton, that can be shaped like a branching tree, a table, a boulder, or other forms, and can reach the size of car.

Scleractinian corals host symbiotic algae in their tissues called zooxanthellae - the algae photosynthesize and provide the coral with most of its energy, but corals also possess a ring of stinging tentacles around each individual mouth in the colony, which are used to capture food such as zooplankton.

Corals are also sensitive to local environmental conditions - warmer water temperatures, sedimentation, nutrient runoff, and heavy metal pollution are just some of the factors leading to the destruction of coral reefs worldwide.

But why should we all be worried about coral reefs, particularly when many of us live very far from the tropical oceans? Coral reefs contain staggering biodiversity.

Estimates vary immensely, but coral reefs may be the most diverse ecosystem on earth; they likely at least rival terrestrial rainforests. Diversity is important for a variety of reasons. Biodiversity ensures that some life will continue to survive, even after major catastrophic events that wipe out many species. Biodiverse ecosystems also provide services, for example nursery habitat to edible fish species, which would be difficult and expensive to reproduce artificially.

Coral reefs provide food to millions of humans. Corals, like trees, provide three-dimensional structure and substrate to house and feed fish and other marine animals that humans eat. Coral reefs protect and create land. Coral reefs can dissipate wave energy from storms and tsunamis, reducing damage on adjacent land.

Atoll islands continue to exist above the ocean's surface long after the volcanic island upon which they first grew has cooled and sunk below the waves, due exclusively to the growth of corals and other reef-associated organisms like large foraminifera. Coral reefs might supply natural medicines. Compounds effective against disease-causing agents like bacteria and fungi already exist in nature - and could be developed into effective drugs for humans if they can be isolated.

The Great Barrier Reef contains over coral species, 1, fish species, 4, mollusc species and six of the world's seven sea turtle species. The Coral Triangle - a coral-rich marine region in Southeast Asia that encompasses the waters between Indonesia, Malaysia, the Philippines and Papua New Guinea - is the most biologically diverse marine ecosystem on Earth.

More than million people worldwide depend on reefs for food, jobs and coastal defence. They help protect areas such as mangrove forests and seagrass beds that act as nurseries for marine animals, as well as human coastal populations. Extracts from animals and plants living on reefs have been used to develop treatments for asthma, arthritis, cancer and heart disease. Despite their great economic and recreational value, coral reefs are severely threatened by pollution, disease, and habitat destruction.

Once coral reefs are damaged, they are less able to support the many creatures that inhabit them and the communities near them. When a coral reef supports fewer fish, plants, and animals, it also loses value as a tourist destination. Healthy coral reefs contain thousands of fish and invertebrate species found nowhere else on Earth. Learn more and view a larger image.

In the s, harvesting sponges was second only to cigar-making in economic importance in the Florida Keys. Nets of recently harvested marine sponges are drying on the top of the boat's wheelhouse. Welcome What are Corals?