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Field Identification Guides for Pacific Coral Species

Seven new resources for the Western Pacific

Six photos in a banner image of individual shots of different coral species.
Image Collage Courtesy of Douglas Fenner

Just as birders have field guides for identification when birding, there are guides on corals for observers as well. With over 6,000 known species, coral reefs are the largest biological origin structures on earth and are complex structures. Many coral species are challenging to identify—even by experts. In partnership with NOAA’s National Marine Fisheries Service (NMFS) Pacific Islands Regional Office, NCEI has released seven coral field identification guides for the Western Pacific Ocean. These guides are a resource for scientists, managers, monitoring teams, and others interested in learning about reef-building corals. 


The guides consist of pictures and information from Wake Island, Tonga, Fiji, Palau, Federated States of Micronesia, the Samoan Archipelago, and Nauru in the Pacific Ocean. 


Field Guides 

The purpose of these identification guides is to learn to determine coral species with photographs and text. They help with over a hundred species and are presented in the conventional taxonomic order using current species names based on DNA-sequencing. 

All photos were taken on site and no species are included that were not present. 

One of the advantages of the field guides in a downloadable PDF is that they can be updated on a regular basis. These guides are currently in the first versions and more corals will be added with future visits to the regions. 

Providing guides for geographically specific areas improves the ability to positively identify. the corals in that location. A more general, worldwide coral identification guide would not provide this level of detail. 

Coral Identification

Coral species identification and taxonomy is challenging. The guides attempt to understand the whole colony shape and close-ups of the corals, and some of the variation between corals. There are valuable identification clues in both the colony shapes and in the features of the coral polyp (an organism that is small and soft that forms the reef)  and areas in between. Viewing as many of these features as possible helps identify the corals.    

The more often a coral is observed, the more opportunities there are to practice identification skills. It is recommended to look at the guide as often as possible, including before entering the water, to be better prepared. Accurate identification may not happen right away, but the more time in the water the more likely it will happen.