Cetacean Forage Survey Underway off the Kona Coast of the Island of Hawaiʻi

March 17, 2014

Researchers aboard the NOAA ship Oscar Elton Sette departed Ford Island, Pearl Harbor today to conduct a cetacean forage survey in waters around the NOAA Kona Integrated Ecosystem Assessment (IEA) region off the western coast of the island of Hawaiʻi. The Sette will serve as a research base for a team of scientist from the NOAA Pacific Islands Fisheries Science Center (PIFSC) working in collaboration with colleagues from the Joint Institute for Marine and Atmospheric Research at the University of Hawaiʻi at Mānoa, Hawaiʻi Institute of Marine Biology at the University of Hawaiʻi, University of Hawaiʻi at Mānoa Department of Oceanography, University of Hawaiʻi at Mānoa Marine Biology Program, Monterey Bay Aquarium, and the NOAA Teacher at Sea program.

The NOAA Ship Oscar Elton Sette is named for the founding Director of the Honolulu Laboratory, which became the NOAA 
        Pacific Islands Fisheries Science Center in 2003.  Dr. Sette was a pioneer in the development of fisheries oceanography. NOAA photo by
        Benjamin Richards.
The NOAA Ship Oscar Elton Sette is named for the founding Director of the Honolulu Laboratory, which became the NOAA Pacific Islands Fisheries Science Center in 2003. Dr. Sette was a pioneer in the development of fisheries oceanography. NOAA photo by Benjamin Richards.

During this 12-day research expedition, the research team, under the leadership of Dr. Donald R. Kobayashi from the PIFSC Ecosystems and Oceanography Division, will be working on two objectives to better understand the dynamics of this unique ecosystem. First, a standard Kona IEA oceanographic and active acoustics survey will be completed to extend the time series of this important survey initiated in 2011 and continued in 2013. Second, a deep nearshore "hotspot" of cetacean foraging will be investigated by a variety of methodologies. Previous surveys have delineated a large daytime and nighttime signal at 400-600m depth nearshore using the Simrad EK60 acoustic sounder at a frequency of 70 kHz, suggesting a forage layer there where organisms are in relatively high abundance. Tagged cetaceans have been recorded feeding within this layer as well as both slightly above and below the layer, leading to many questions about the faunal composition of the layer and its relationship to key cetacean forage such as large cephalopods. The scientific field party will use a variety of oceanographic survey instruments and methods to investigate the forage layer and the fauna in surrounding waters, including active acoustic surveys; a remotely operated vehicle (ROV) deployed from the Sette with both a navigational real-time camera and a recording stereo video camera system; a BlueView sonar imaging unit attached to the ROV; a Didson sonar imaging unit lowered on a CTD rosette; GoPro cameras; baited deep handlining and squid-jigging; and a Cobb midwater trawl.

In addition to the multi-faceted survey, the research team will carry out ancillary projects including deployment/recovery of 2 High-frequency Acoustic Recording Packages (HARPs) used to characterize cetacean identification, distribution, and abundance.

Operational area of the research expedition in the Kona IEA region. The star symbols A-F indicate locations of the standard Kona IEA 
        grid stations, and circle symbols H1 and H2 indicate locations of HARP deployments and/or recoveries. Some targeted research 
        operations will focus on the nearshore stations (A & C) where deep cetacean foraging "hot spots" have been characterized 
        previously.
Operational area of the research expedition in the Kona IEA region. The star symbols A-F indicate locations of the standard Kona IEA grid stations, and circle symbols H1 and H2 indicate locations of HARP deployments and/or recoveries. Some targeted research operations will focus on the nearshore stations (A & C) where deep cetacean foraging "hot spots" have been characterized previously.