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Did you know?

• Corals are one of the planet's most complex and diverse ecosystems.

• Corals grow to be massive and complex physical structures that can be seen from space.

• Corals have high economic value (fishing, tourism, etc.).

• Corals help to protect against coastal erosion by buffering wave action.

• Corals provide food and shelter for thousands of reef fishes and other marine animals.

Threats to Coral Reefs

As global climate change accelerates, much of the ocean’s ecosystems are increasingly threatened. Coral reefs are an example of a vulnerable ecosystem significantly impacted by sea temperature rise, acidity, pollution, algal abundance, etc. Below are some of the main threats to American Samoa's coral reef.

Different Shapes and Growth Forms of Coral Colonies

Image of branching/staghorn coral

Branching/Staghorn Coral

the fastest-growing coral and are tree-like. The growth rate is 10-15 cm per year.

Image of boulder coral

Boulder Coral

The slowest-growing coral, with a growth rate of 1 - 3 cm per year. Some large colonies can be up to hundreds of years old.

Image of table/plate coral

Table/Plate Coral

Designed to collect as much sunlight as possible. Found in deeper areas on the reef slope where the light levels are low.

Image of brain coral

Brain Coral

Brain coral polyps do not form complete walls around themselves and create lines of mouths separated by skeletal ridges, making it look like a brain.

Image of foliaceous coral

Foliaceous Coral

Form horizontally flattened plates that may form tiers, whorls, or vases, which can be stacked in a multi-layered arrangement—their flattened shape results from radial (edge) rather than vertical extension.

Image of mushroom

Mushroom Coral

Different from most hard corals as it is a single polyp that lays free on the reef. It can be round or oblong, up to 9.8'' (25 cm).      

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