- Special Projects
Updated 12:05 p.m., 12/21/2017
Miles of fishing line, trawling gear and huge nets have decimated ancient coral reefs at undersea mountains in remote areas of the Pacific, a recent research expedition has found.
A team of scientists, operating two three-person submarines off of a support vessel, explored a dozen seamounts last fall on 76 dives. Some were in protected waters inside Papahanaumokuakea Marine National Monument in the Northwestern Hawaiian Islands and others were in unregulated international waters in the southern part of the Emperor chain closer to the Aleutian Islands.
While a full report on the expedition is not yet available, researchers said their initial findings clearly underscore the importance of marine reserves in safeguarding these deepwater ecosystems — cold and dark places that some of the world’s oldest living and most fragile animals call home.
The research comes at a crucial time. The commercial fishing industry and regional fishery management councils have been pressuring President Trump to lift fishing restrictions within certain marine monuments and give them more control over how the reserves are run.
But it’s also a vital moment for the manned submersible program itself. This could end up being the last expedition for the two old subs as part of the Hawaii Undersea Research Lab, which is based on the Makai Research Pier on the east side of Oahu.
Terry Kerby and Maximillian Cremer, who have decades of experience piloting the subs and directing operations at the lab, said in interviews last week that they returned from the expedition in November with a sense that it was among the most important trips they have ever taken.
“No one has ever really investigated these to see what is going on there,” Kerby said of the seamounts, which are undersea mountains. “What we found on the bottom was just devastation. It looked like it had been swept with a giant wire brush.”
But just days later, they learned that Brian Taylor, dean of the University of Hawaii School of Ocean and Earth Science and Technology, which oversees the lab, had made the “very difficult decision” of ending operations for the two subs, Pisces IV and Pisces V, and the support vessel, the Kaimikai O Kanaloa. Taylor did not respond to a message seeking comment.
Taylor explained in an internal email that the university does not have the funds to cover the anticipated $1.5 million to $2 million needed for a required dry dock of the support vessel. Facing an Aug. 30 deadline, he said there is also no time or funding to prepare the subs for a final dive season in the ideal September-October window.
“This decision could only be reversed by a gift of $2M in the very near future for KOK/PISCES IV refits (independent of ship/sub operations costs),” Taylor wrote.
Kerby described the subs as “really rugged working-class” vessels that the university got for a bargain in the 1980s. It cost $4 million to build one in 1973, he said, but would cost about $50 million today.
Taylor said he is investigating options to “gracefully retire” the KOK and the subs from UH service in 2018, possibly via their “joint operation by an overseas partner.”
In parallel, he said they have scheduled sea trials in January to bring Luukai — a remotely operated vehicle that can reach depths up to 6 kilometers — up to full operational status on the R/V Kilo Moana support ship.
The dean commended the team on its seamount expedition, which was funded by the National Science Foundation for the project’s principal investigators, Brendan Roark of Texas A&M University and Amy Baco-Taylor of Florida State University. Roark and Baco-Taylor did not respond to messages seeking comment.
The project’s purpose was to assess the recovery of seamounts from trawling by exploring sites that have never been trawled, sites that were trawled but have had roughly 40 years to recover, and sites that are still trawled, according to Baco-Taylor. The focus was deep-sea corals and sponges.
“Some areas on the upper reaches of these seamounts look like the deep sea analog to swaths of clear-cut rainforest in the Amazon region,” Cremer said, describing the scene of plowed-over dead coral trees that were likely 1,000 to 2,000 years old.
Bottom trawling involves dragging a massive net along the sea floor. Rubber discs or large metal balls, sometimes called rock-hopper gear, are attached to the rope near the mouth of the net to help avoid entanglements.
Cremer described areas on the seamounts that looked like “violent battles” where the fishermen’s nets did get stuck and they tried to set them free, as the gear is quite expensive.
“It would be like taking this net through the forest and you go through and it takes up all the pines and oaks and all the deer and the raccoons and everything else in this giant net and you just clean sweep everything out and you throw away everything except the squirrels,” Kerby said, noting the huge dead coral trees and scarring in the seamounts that they encountered.
But other areas showed signs of recovery. Sprigs of gold coral were found at the Hancock seamounts inside Papahanaumokuakea, which has been protected as a monument for a decade and from international fishing fleets for a generation.
“We strongly believe that these findings can contribute important first-hand visual data to the discussion around expansion versus reduction of sanctuary sizes,” Cremer said.
President Obama quadrupled the size of Papahanaumokuakea last year, making it the world’s largest protected place at the time. He also expanded Pacific Remote Islands, another monument that was initially created by President George W. Bush.
Update Years prior to the monument designation, the Western Pacific Regional Fishery Management Council prohibited bottom trawling in the U.S. exclusive economic zone waters around Hawaii and the other U.S. Pacific Islands, covering 2.2 million square miles. A 1986 fishery management plan banned destructive fishing techniques, including trawl nets, and established a moratorium on the commercial harvest of seamount groundfish stocks at the Hancock Seamounts that continues to this day, according to Wespac.
Bob Humphreys, a retired National Oceanic and Atmospheric Administration fisheries biologist who has done research dives with Kerby, said ending the manned submersible diving program would mean losing expertise in addition to the subs.
“It’s a tremendous asset,” he said. “It’s too bad, but everybody is strapped for funds. I feel their pain.”
Kerby explained that the manned subs can access areas that the remotely operated vehicles can’t because they are tethered to a support vessel at the surface.
He said the ROVs certainly are a tool that scientists need, but he said the technology is not there yet to compete with the manned subs in many regards. The cliffs and overhanging arches on the seamounts, for instance, present snagging hazards for the ROVs but are easily accessed with the subs. The subs can also cover significantly more ground.
UH graduate student Jessica Perelman was able to go on the last expedition, sitting as one of two observers in each sub that watch out the small circle windows as Cremer or Kerby steers them around thousands of feet underwater. Each dive is several hours spent transecting an area, collecting samples with the sub’s robotic arms and recording everything.
“I had the craziest, most incredible experience of my entire life,” she said.
Aside from the leftover trawling gear and fishing line, Kerby said, they found nets from dredging for corals used in jewelry.
Cremer described the seamounts, which are almost all volcanic in origin, as “sunken islands” with their cliffs and slopes rising at least 1,000 meters from the sea floor. They are hot spots for fish aggregation because of upwelling in the ocean.
A 1984 research paper by Humphreys, Michael Seki, the current director of NOAA’s Pacific Islands Fisheries Science Center, and Darryl Tagami discusses the pelagic armorhead fish that trawlers from Japan and the Soviet Union targeted in the late 1960s and 1970s at seamounts in the Emperor-Hawaiian Ridge.
During their heyday, more than 22,000 tons of armorhead were caught in a single year. But by the late 1970s, almost no fish were caught there. By 1984, it had been fished to “commercial extinction.”
“There were no regulations, at all,” Humphreys recalled, noting how this was during the big space race time and major global powers were exploring the ocean as well.
“A lot of people really didn’t know what was going on for awhile until some of our scientists started translating some of the information,” he said, noting that U.S. fishermen never got involved because this fish was not really eaten in the states or Europe.
Interim management measures were eventually set up in 2007, Humphreys said, with South Korea and China participating. Independent observers were put on boats, certain seamounts were closed and there were restrictions on trawling during spawning seasons so the armorhead could recover.
“Everybody thought at first there was such a huge bounty of fish taken off seamounts that they could have a longterm sustainable fishery with them,” he said. “But people didn’t realize, like with orange roughy, how easy it is to fish out a seamount. … You wipe out those old individuals and it will take decades to get back to that.”
Humphreys said he expects international fishing regulators will be interested in the findings from the most recent seamount expedition. And he suspects they will grapple with questions about whether certain seamounts should be closed, and if so, how long?
“You only get snapshots of time,” he said, referring to the challenge of making sweeping management decisions based on an expedition of a dozen seamounts out of thousands across the ocean. “It’s difficult.”
Kerby said the research team saw “the truth” of what the monuments really mean.
“It’s totally irresponsible to open up areas to fishing that are totally unique to the world,” he said.
Robert Richmond, director of the Kewalo Marine Laboratory and a driving force behind the expansion of Papahanaumokuakea, said the photos he has seen from the expedition support his position.
“The photos clearly show the tremendous damage done by trawlers to the unique, extremely slow growing and fragile creatures living on the seamounts, and reinforce the value of expanding the monument boundaries,” he said.