A research ship was launched Thursday on the first leg of a six-month mission to survey whales, dolphins and seabirds across the Hawaiian archipelago, a vast expanse of 1.8 million square nautical miles.
The crew aboard the National Oceanic and Atmospheric Administration ship will scan the seas with high-powered, deck-mounted binoculars, tow passive listening devices underwater and use a drone. The goal is to get a clearer picture of the state of various species, from spinner dolphins to false killer whales.
“Animals are difficult to see if you are only looking with the naked eye,” said Erin Oleson, co-chief scientist at NOAA’s Pacific Islands Fisheries Science Center. “In addition to the ‘big-eye’ binoculars, we will also be using passive acoustic listening methods. Whales and dolphins use sound, primarily, to communicate with each other, so we are essentially eavesdropping.”
The undertak ing is known as the Hawaiian Islands Cetacean and Ecosystem Assessment Survey, dubbed HICEAS and pronounced “high seas.” Cetaceans include whales, dolphins and porpoises.
The voyagers will estimate population numbers and distribution, and evaluate the health and habitat of species around the main and Northwest Hawaiian Islands — up to 200 miles offshore.
“We will be covering that entire area with our two ships,” Oleson said, with about 15 scientific crew members on each 30-day leg of the voyage.
The ship that left Thursday, the Oscar Elton Sette, will handle the first half of the 187-day expedition, followed by the NOAA ship Reuben Lasker.
The survey is called for under the Marine Mammal Protection Act and the Endangered Species Act, and follows similar surveys that were conducted in 2002 and 2010. It is the first comprehensive survey since the expansion of the Papahanaumokuakea Marine National Monument in August.
NOAA is collaborating with other agencies on the voyage, including the Bureau of Ocean Energy Management, the Navy and the U.S. Fish and Wildlife Service.
Along with about two dozen species of cetaceans, the researchers will survey seabirds. Crews will count any seabirds that come within 300 meters of the ship, and also assess feeding flocks that are farther away. Seabirds are good indicators of ocean conditions and health.
The inventory of whales, dolphins and seabirds will also help determine whether fisheries bycatch rates are sustainable.
The scientists will test new methods of tracking animals, including environmental DNA, which is genetic material released by an organism into its environment, such as in feces, mucus or skin.
“We will be collecting water samples to evaluate whether we can use environmental DNA, eDNA, to identify species which are difficult to identify based on sight alone,” Oleson said in a briefing with reporters.
The voyage will produce new estimates of false killer whales, in support of the False Killer Whale Take-Reduction Plan. False killer whales forage on the same fish species that people like to eat, and steal catch from long-liner hooks or get caught themselves.
“The data we are collecting in the survey will be fairly critical for their management efforts,” Oleson said. “This year’s data will help us better understand whether that population is stable or in decline or increasing.”
To follow the mission online, visit www.pifsc.noaa.gov/hiceas.