David Hall's Encounters in the Sea Photography

Corals

Corals, sea anemones and their relatives belong to a group of animals called Cnidarians. Coral colonies are composed of individual polyps that have six or more tentacles, each lined with stinging cells (nematocysts). There are several different kinds of corals and coral-like animals. Hard corals secrete limestone skeletons and are responsible for the creation of tropical coral reefs. Related animals - such as soft corals, gorgonians and sea pens - do not construct reefs, but are nevertheless important to reef ecology.

Reef-building corals gain energy and nutrition from symbiotic algae that live within their tissues, and that may impart a distinctive color to their hosts. Most corals grow very slowly - often only inches a year - but over a period of thousands of years they can create enormous structures such as atolls and barrier reefs.

Coral Reef, Fiji	Coral Reef, Micronesia	Coral Reef, Indonesia
Coral Reef and Jacks, New Guinea	Coral Reef, New Guinea	Coral Reef and Fusiliers, Solomon Islands
Sea Fan, Fiji	Hard Corals, Fiji	Soft Corals, Fiji
Table corals, Indonesia	Sea Pens, British Columbia	Cabbage Coral, Fiji
Broccoli Coral, Indonesia	Soft Coral, Indonesia	Soft Coral, Papua New Guinea
Sea Fan, New Guinea	Sea Fan, Indonesia	Sea Fan, Indonesia
Hard Coral, Indonesia	Daisy Coral, Indonesia	Gorgonian Coral, Caribbean
Black Coral, Indonesia	Tube Coral, Red Sea	Wire Coral, Indonesia
Soft Coral, Indonesia	Hard Coral, New Guinea	Whip Coral, New Guinea
Hard Coral, Palau	Spawning Coral, New Guinea	Hard Coral, Indonesia
Hard Coral, Japan	Sea Fan, New Guinea	Hard Coral, New Guinea
Mushroom Coral, Indonesia	Anchor Coral, Indonesia	Sea Fan, Indonesia
Corallimorpharians, Tasmania	Star Coral, Caribbean	Zoanthids, Tasmania