About the Ecosystems and Oceanography Division

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The Ecosystems and Oceanography Division (EOD) conducts research to advance our understanding of the structure and dynamics of central North Pacific marine ecosystems. In particular, we seek to understand how marine populations change in response to both direct changes in their predators and prey as well as from broader habitat-based changes in the ocean climate including El Niño, La Niña, and other interannual or decadal events.

Current work is addressing ecosystem and environment impacts for a range of species including the Hawaiian monk seal, several species of sea turtles, and many species of large pelagic fishes including a mix of both commercially important and bycatch species of tunas, billfishes, sharks, and other incidental species.

Loggerhead sea turtle with ARGOS satellite tag
Loggerhead sea turtle with ARGOS satellite tag

EOD products include scientific advice towards stock assessment and fisheries management, development of indicators of ecosystem changes, and the publication of scientific findings related to habitat/environmental effects on individuals, populations, ecosystems, and fisheries. To accomplish these goals, EOD researchers utilize a broad spectrum of advanced tools such as deep diving submersibles/remotely operated vehicles (ROV)/SCUBA, small and large research vessels, popup satellite archival tags, animal-borne instrumentation such as crittercam, acoustic survey techniques using shipboard and moored echosounders, satellite remotely-sensed oceanographic and atmospheric data products, ocean circulation models, ecosystem modeling, advanced statistical approaches such as empirical orthogonal functions, kalman filters, generalized additive models, and numerical modeling approaches to quantify active movement and passive transport.

Since EOD research covers many different scales ranging from fine-scale habitat characterization to basin-scale oceanography, and from short-term individual foraging behavior to long-term ecosystem changes and population trends, a variety of approaches are necessary including interdivisional, multiagency, academic, industry, non-government organizations (NGO), and multinational collaborations.

Research Focus

EOD has ongoing research with movement patterns of large pelagic animals (sea turtles, bigeye tuna, albacore tuna, moonfish, pomfret, marlin, swordfish, and mako sharks) based on popup archival satellite tags, mitigation of protected species (sea turtles and cetaceans) in pelagic longline fisheries, acoustic surveys of tuna forage in key locations of the central and western Pacific ocean, acoustic surveys of juvenile snapper (opakapaka) in a nursery area off windward Oahu, metapopulation connectivity of insular species in the Hawaiian archipelago using numerical modeling of larval transport and retention in conjunction with high resolution ocean circulation model output, and various pelagic and insular habitat characterizations using a combination of in-situ and remotely-sensed data products.

EOD has ongoing collaborations with PSD regarding sea turtles, cetaceans, and monk seals, and collaborations with CRED and FRMD staff with nearshore oceanography and the ecology of large pelagics. EOD also collaborates with staff from other science centers with sea turtles and cetacean research, and maintains numerous collaborations with the University of Hawai'i, Pelagic Fisheries Research Program (PFRP), Hawai'i Institute of Marine Biology (HIMB), and many other academic and research institutions.