Coral Reef Animals (Invertebrates)

Coral reef animals are overwhelmingly the most conspicuous component of coral reef life, occurring in truly astounding numbers and variety in virtually every part of coral reef ecosystems.

The animal kingdom is often informally divided into two major groups: animals with backbones (called vertebrates) and those without these structures (called invertebrates).

By far, most animal species are invertebrates. In fact, of the 26 or so major divisions (phyla) recognized within the animal kingdom, 25 are exclusively composed of invertebrates.

Not only are invertebrates the most diverse and numerous of all the animals inhabiting coral reef ecosystems; they are also the primary builders of coral reefs and an integral part of many aspects of the ecology of coral reef ecosystems.

Invertebrate animals in all coral reef zones and habitats are instrumental in the movement and cycling of nutrients through the ecosystem. Many of the animals in coral reef sediments engage in activities such as burrowing or tunneling that shape the very nature of these environments.

Some invertebrate coral reef animals (parasites) infest the bodies of other invertebrates and coral reef fishes, while others are vectors for disease. Still other invertebrates serve a cleaning function, removing parasites and damaged tissue from other types of reef life.

Invertebrate animals dominate coral reef communities. Photo courtesy NOAA

Even a summary treatment of what is currently known about the amazing variety of form, life histories, behavior, and ecology of the invertebrate animals found in coral reef ecosystems would fill many volumes, and a great deal remains to be learned in this area.

Thus, this 7-page section of our web site is intended to provide a useful, but necessarily brief, introduction to the six most common groups of invertebrate animals typically seen in coral reef ecosystems. The groups so include are the corals and their relatives (cnidarians), the sponges, the echinoderms, the mollusks, the crustaceans, and the polychaetes.

Related Pages

Corals And Their Relatives
Information and facts about the group of animals called cnidarians (which includes corals, hydrocorals, and anemones), and their distribution and roles in coral reef ecosystems

Coral Reef Sponges
Information and facts about the types of sponges common in coral reef ecosystems, and their ecological roles

Coral Reef Echinoderms
The main types of echinoderms commonly inhabiting coral reef ecosystems and their ecological roles

Coral Reef Mollusks
Information and facts about the various types of mollusks commonly found in coral reef ecosystems

Coral Reef Crustaceans
Information and facts about crustaceans (shrimp, spiny lobster, crabs) commonly found in coral reef environments

Coral Reef Polychaetes
Information and facts about polychaete worms commonly found in coral reef environments