Researchers to document marine life around Hawaii
Using high-powered binoculars, hydrophones and, for the first time, drones, researchers with the National Oceanic and Atmospheric Association will spend the next six months documenting whales, dolphins and other marine life around the main and Northwestern Hawaiian Islands.
Crew with the NOAA Fisheries Pacific Islands and Southwest regions began a 187-day journey Thursday afternoon that will soon take them through Maui waters.
The mission is the third installment of the Hawaiian Islands Cetacean and Ecosystem Assessment Survey, which researchers hope will help them better understand population trends, health and habitats of dolphins and whales.
“We’re very excited to get started,” Erin Oleson, co-chief scientist with the NOAA Pacific Islands Fisheries Science Center, said Thursday morning. “The main population of cetaceans we’re concerned about is false killer whales, primarily because of the interactions with the longline fishery here in Hawaii. . . . We don’t have a good sense of the population trends at this point. Hopefully, this year’s data will help us understand whether that population is stable.”
According to Oleson, the Hawaiian archipelago is home to at least 25 different species of cetaceans, which include dolphins and whales. Stephanie Stack, senior research biologist with the Maui-based Pacific Whale Foundation, said that some of the most common species in the Maui Nui area are spinner, spotted and bottlenose dolphins, as well as false killer whales.
From now until December, a research crew of 15 will travel 1.8 million square nautical miles aboard the 224-foot Oscar Elton Sette and the 209-foot Reuben Lasker. Their expedition will take them from a couple miles to 200 miles offshore. This time, NOAA also will be working with the Bureau of Ocean Energy Management, the U.S. Navy and the U.S. Fish and Wildlife Service.
Researchers are trying to replicate similar NOAA surveys done in 2002 and 2010 to get a sense of population trends, and this year’s survey will have a little boost in technology through hexacopters, or drones.
Last summer, NOAA conducted practice runs with drones to see how they might handle different weather, and how lighting and glare might impact photographs, Oleson said. It’s the first time since doing the pilot studies that NOAA will be using the drones, which will come in handy when observing species like pilot, sperm and false killer whales, “fairly cooperative species” that don’t move very fast and don’t dive underwater for long periods of time, Oleson said.
False killer whales, whose large, conical teeth are just about the only physical similarity to orcas, are of special interest to the team because of their contact with longline fishing vessels.
“False killer whales are foraging the same species people want to eat,” Oleson said.
When the animals try to swipe fish caught on longlines, they’ll sometimes get hooked themselves. But often, it simply means the fisherman is left without a catch, Oleson said. The NOAA Fisheries’ false killer whale take reduction team is working to find solutions that will not only protect the whales but also the fishermen’s livelihood.
“The data that we’re collecting will be critical for their management efforts,” Oleson said.
The main Hawaiian Islands insular false killer whale was placed on the endangered species list in 2012, when it was estimated that there were fewer than 200 of them in Hawaii, Stack said.
“We’re a small team . . . so we don’t see them very often at all,” Stack said. “So it’ll be nice to see what NOAA comes up with. . . . Not a lot is known about their distribution and the way they use these islands.”
Researchers also will spend the six-month expedition using underwater recorders and hydrophones to listen in on whales and dolphins as they forage and communicate. They’ll tag animals, collect cell samples and make note of their health and surrounding habitat.
With humpback whale season lasting from November to May, Oleson acknowledged that “unfortunately we’re not really hitting the peak of their seasons.”
However, the team wants to finish the survey before the winter months set in and is trying to replicate the timing of the previous surveys so the data can be compared.
The survey will help NOAA better understand the species of whales, dolphins, sea turtles and seabirds in the Papahanaumokuakea Marine National Monument, which President Donald Trump has included amongst two dozen other national monuments up for review.
Researchers aren’t trying to determine whether Papahanaumokuakea should stay the same size; they’re just trying to collect a library of data that different agencies can use in their environmental and climate assessments, Oleson said.
To follow the voyage, visit pifsc.noaa.gov/hiceas.
* Colleen Uechi can be reached at cuechi@mauinews.com.