Coral reef resources are the subject of a 60-day study by NOAA scientists and their research partners in the Northern Mariana Islands

September 3, 2005
The Oscar Elton Sette off of Guguan Island during the 2003 expedition
Photo by R. Schroeder

The NOAA Ship Oscar Elton Sette departed Honolulu on August 16, 2005 for the island of Saipan where a team of scientists will embark for a 60 day investigation of the islands of the Commonwealth of the Northern Marianas Islands, Guam, and Wake. A collaborative study between NOAA scientists, local scientists, and collaborators from various universities, this important expedition will focus on assessing and monitoring the coral reef resources of these seldom explored areas. The expedition is part of the biennial monitoring effort in the region by the Coral Reef Ecosystem Division of the Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service, NOAA, in Honolulu, Hawaii. The Chief Scientist for the cruise is Dr. Robert Schroeder, a lead member of the PIFSC research team employed by the NOAA-University of Hawaii Joint Institute for Marine and Atmospheric Research (JIMAR).

A giant Grouper (Epinephelus lanceolatus) at Agrihan in 2003. Giant groupers are rarely encountered by divers - especially in areas with heavy fishing pressure.
Photo by R. Schroeder

Due to its length, the expedition is divided into four parts with some scientists being replaced each time the ship comes into port. The first leg of the cruise will take the researchers northward from Saipan to the islands of Anatahan, Guguan, Pagan, Asuncion, Uracas, Maug, Supply Reef, Agrihan, Alamagan, Zealandia Bank, and Sarigan. These islands are remote and largely uninhabited and can best be explored from the platform of a large ship like the Oscar Elton Sette. One of the highlights of this leg of the expedition will be the opportunity for the scientists to conduct research in waters surrounding active volcanoes where gas is bubbling up from the sea floor.

After 18 days, the ship will return to Saipan, change some of its staff, and then ship out for the second leg of the cruise which will operate around the islands of Anatahan, Pathfinder Reef, Arakane Reef, Tinian, Aguijan, and Rota. The research team will finish this leg in Guam and will once again enter port to exchange staff and refresh supplies. The third leg of the cruise in the Marianas will center around the heavily populated island of Guam. After surveying the waters of Guam for 7 days, the ship will again return to port and exchange staff before setting sail for the long transit back to Honolulu. During the return voyage, the ship will be stopping for 5 days of operations around Wake Atoll, where JIMAR researcher Molly Timmers will serve as the Chief Scientist.

A pair of scientists conducting towed-diver surveys. They are pulled behind a small boat and are able to survey large areas of reef in a short period of time.
Photo by R. Schroeder

During each leg of cruise operations, the scientists will be conducting comprehensive monitoring surveys of the shallow-water marine resources. Teams of specialists will assess the status of the fishes, corals, algae and marine invertebrates using underwater survey techniques conducted while SCUBA diving from small boats launched from the Oscar Elton Sette. Fine scale assessments will be made by divers surveying along 25 meter transect lines, and larger scale assessments will be made by towed-diver surveys. Additionally, teams of oceanographers will be working from the ship conducting underwater acoustic surveys and deploying various monitoring platforms to collect oceanographic data. One new tool the scientists will deploy is a deep water remote camera bait station known as BOTCAM. BOTCAM will be deployed in depths up to 350m where it will release bait and then record high resolution digital stereo-video imagery in an effort to monitor the substrate and deep water fishery species attracted by the bait.

This is the second PIFSC expedition to the Marianas. Accordingly, it will offer the research team the opportunity to revisit sites of particular interest identified during the 2003 expedition as well as explore new areas. The expedition will provide valuable data to increase our understanding of the ecological and environmental processes occurring in U.S.-related islands across the Pacific Ocean.