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.

Monday, April 11, 2011

Heading north....

by Edmund Coccagna

We have left the populated southern islands of the CNMI behind and have entered the area of the Northern Mariana Islands.  The region is somewhat of a mystical place where volcanoes rise sharply out of the sea, forming perfectly cylindrical cones.  Some of the islands have been inhabited by lush vegetation, while others were left with nothing but bare ash and rock.  Historically, these islands have been marked by violent volcanic eruptions caused by their geographic location on one of the earth’s major subduction zones along the Marianas Trench.  Over time they have developed and in turn eroded into what we now see, which is quite the spectacle of where land meets the sea.
The safeboat tucks inside of a cliff side cave with a view of the ship in the background. NOAA photo by Jason Helyer.
Our first stop in the region was at the small island of Sarigan.  The appearance of Sarigan is much like the others, with dramatic rock features created by the island’s violent past, both above and below the surface of the water.  The terrestrial habitat of Sarigan is marked by vegetation on the western side and sheer basaltic rock on the eastern side with many tremendous formations.  People have inhabited the island at different times in the past, but currently no one currently resides on the island, except for birds and insects.  Below the surface, the majority of the reef habitat is formed of large boulders or basaltic rock with low to moderate levels of coral cover.  Sarigan does host the greatest populations of large bodied reef fish that we have encountered on this trip yet.  Divers on the fish teams reported sightings of three different types of sharks, including white tip reef sharks, grey reef sharks, and Tawny nurse sharks, large Napoleon wrasses, and large schools of jacks, barracudas and rainbow runners.
Area of Porties rus. NOAA photo by Jacob Asher.

Sarigan is one of only two islands that the US Geological Survey (USGS) actively monitors.  The current status of the advisory is safe with no alerts, which was good news for the small boats working in the vicinity of the island.  Although the date of the last eruption on Sarigan is unknown, a seamount seven miles to the south experienced an explosive eruption in late May of 2010, which caused the USGS to close access to the nearby islands in the chain, including Sarigan.  The submarine volcano reportedly blasted ash 49,000 feet into the atmosphere!  That is incredibly impressive considering the origin of the blast occurred well below the surface of the water.   
The island of Sarigan, Northern Mariana Islands. NOAA photo by Annette DesRochers.
We only spend one day at Sarigan due to its small size and then head north to Pagan.  Many other volcanoes rising from the water await and there are many more stories to come.

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