From the Field: Coralline Algae: The Unsung Architects of Coral Reefs


During a recent cruise to the Southern Line Islands, I, along with other researchers from Scripps Institution of Oceanography, UC San Diego, had the opportunity to sample coralline algae across this Pacific island chain. These nearly pristine reefs have large numbers of grazing fish, which means that any non-coral surface is likely to be covered with the crusty pink algae. We noted that the Southern Line Islands are host to a wide diversity of coralline species. The most charismatic of them all was found at Starbuck Island, where pillars of thick, bubblegum-colored coralline algae (Hydrolithon craspedium) coated any available space on the bottom. To collect these specimens, researchers had to use hammers and chisels to pry the 2-inch-thick algae off the reef. That is some effective reef cement!

So from now on when you think of coral reefs, don't forget about the stealthy coralline algae that toil in the shadows of coral, strengthening and enriching the coral reef habitat.

- Maggie Johnson is a third-year student in the laboratory of Scripps marine biologist Jennifer Smith. This text is excerpted from Johnson's blog written for the Smithsonian Institution's Ocean Portal. To read the full post and explore more about coral research at Scripps, visit

Related Image Gallery: Coralline Algae: The Unsung Architects of Coral Reefs

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