A Better Understanding of Coral Reef Ecosystems

Pelagic predators such as these barracuda, Sphyraena qenie, are part of the coral reef ecosystem in the U.S. Line Islands (NOAA Photo by Kevin Lino).
A team of scientists have embarked from Hawai'i on a three-month survey of coral reef ecosystems at Johnston Atoll, the U.S. Phoenix Islands, the islands of American Samoa, and the U.S. Line Islands in the tropical Pacific Ocean. The overarching objective is to better understand the coral reef ecosystems of these areas, many of which are seldom explored. The research expedition is part of a regular monitoring program, conducted by the Coral Reef Ecosystem Division (CRED), headquartered in Honolulu, Hawai'i. The expedition is supported by NOAA's Coral Reef Conservation Program and involves extensive cooperation among NOAA scientists and research partners, including the University of Hawaii Joint Institute for Marine and Atmospheric Research (JIMAR), the U.S. Fish and Wildlife Service, San Diego State University, and the Papahānaumaokuākea Marine National Monument.

The research expedition will be carried out from February 27 to May 24, 2012 aboard the NOAA ship Hi'ialakai. Under the leadership of Chief Scientists Dr. Jill Zamzow, Dr. Bernardo Vargas-Angél, and Jamison Gove, a diverse team of researchers will be conducting multidisciplinary coral reef ecosystem surveys, assessing the status of fishes, corals, algae, marine invertebrates, and the oceanographic conditions in which these organisms exist. The scientific data collected during the three-month research expedition will enable informed and effective implementation of ecosystem-based management and conservation strategies for coral reef ecosystems, helping to ensure their protection for generations to come.

Thursday, January 28, 2010

Concerning Corals

by Jean Kenyon and Erin Looney
photos by Benjamin Richards and Jason Helyer

Stony corals (Class Anthozoa, Order Scleractinia) are marine invertebrates that secrete a calcium carbonate skeleton.  Stony corals can be hermatypic (significant contributors to the reef-building process) or ahermatypic, and may or may not contain endosymbiotic algae called “zooxanthellae”.  The largest colonial members of the Scleractinia help produce the carbonate structures known as coral reefs in shallow tropical and subtropical seas around the world.  The rapid calcification rates of these organisms have been linked to the mutualistic association with the zooxanthellae, found in the coral tissues.  Massive and branching stony corals are the major framework builders of shallow tropical reefs.  Some stony corals occur in deep water and are azooxanthellate (they do not contain zooxanthellae), but these deep water corals typically do not form extensive reefs. Corals are arguably one of the most important components of the coral reef system, providing substrate for colonization by benthic organisms, constructing complex protective habitats for myriad other species, including commercially important invertebrates and fishes, and serving as food resources for a variety of animals.

While at Johnson Atoll we are collecting data on corals that will tell us more about species abundance and distribution, size class distribution, and disease.  Each site we visit differs in terms of species dominance, the relative abundance of coral, and the health of the corals present.  Many factors contribute to this, including the location of the reef (whether it is a backreef, forereef, or in a lagoon), wave intensity, and its closeness to human population and associated pollution.  One would expect that reefs as far removed as Johnston would be pristine, healthy, flourishing environments, but even these are subject to disturbances such as hurricanes, marine debris, and pollutants introduced to the environment throughout history.  Especially in the Pacific, many island which are not currently inhabited, have had sizable human populations in the past. Johnston is one of these and, we find a relatively high prevalence of coral disease at Johnson Atoll compared to other islands.

Although these reefs may not be as pristine as we might hope, they are by far some of the most beautiful and deserve our best efforts in understanding the dynamics that keep them thriving. Every day we are amazed by something new, something we've never seen before (possibly that no one has seen before), and are reminded of why we are out here, trying to learn more about this complicated and amazing environment.


  1. I was an Army MP on Johnston Atoll Jan 1990 to Apr 1991. The diving was spectacular. I'm enjoying your blog updates. It's good to see the Atoll is doing reasonably well. I remember seeing plenty of white tip and grey reef sharks plus the moray eels. I remember seeing red coral which I'm told is sort of rare. I'm sure there'd be more of it left had the government not allowed JI folks to harvest it for decorative coral boxes which we were given customs documents allowing us to bring that stuff home. I never did. Some guys would kill some of the sharks they caught for their jaws. Wasn't into that either, but did enjoy fishing for them and throwing them back. We used to "camp out" on North Island.... those were good times. We were only allowed on the perimeter of North Island... to protect the birds. Wish I was there diving with you all! Take care.

  2. Awesome roomie-thanks for the info! You all are doing a wonderful job. Thanks for the hard work.

  3. Wow, surprised about the disease incidence! Is this a recent occurrence?

  4. Wow, surprised about the disease incidence! Is this a recent occurrence?
    Sounds like you are having fun!