As I make my way down the hallway on the main deck of E/V Nautilus, my mind is set on getting to my bunk. I’ve been awake since 4am and it’s now almost 10pm. But then I notice Eric Hayden walking out of the Data Lab, smiling to himself.
He spots me. “Marley! Have you seen it yet??”
“Seen what?” I ask, ignoring my fatigue. I’ve sailed with Hayden on three different expeditions, and I’ve never seen him this excited.
“The video!”
Hayden immediately turns around and beckons me to follow him back into the Data Lab, where the Mesobot team has set up shop. When I glance over at Dana Yoerger, I’m not surprised to see he is glued to the laptop in front of him. Like most engineers, he and his team are methodical. They spend hours and hours diligently reviewing data from Mesobot’s latest mission and planning out the next mission. But right now, they are celebrating. Hayden turns his laptop towards me, and says, “check this out.” Yoerger swivels around in his chair to watch over my shoulder. He is beaming.
The source of their elation swims across Hayden’s laptop screen – thick salp chains glide through the blackness while squid zoom in and out of the frame. Marine snow, tiny krill, and phytoplankton pepper the scene. The swirl of bright, twinkling organisms looks like something out of a science fiction movie – it feels like we’re viewing the far reaches of outer space.
But this is inner space, specifically the Ocean Twilight Zone. We are watching footage that Mesobot just captured, 150 meters below us.
Hayden’s gaze is locked on the screen. “It’s like we’re sitting inside a fish tank,” he says. “Look at that ink trail from the squid!”
We watch, transfixed, as the animals continue to dart around Mesobot. We marvel at the crisp quality of the footage and the sheer number of organisms. Yoerger points out that the small fish we’re seeing are likely some of the most numerous vertebrates on the planet – but humans very rarely get the opportunity to observe them.
Hayden immediately turns around and beckons me to follow him back into the Data Lab, where the Mesobot team has set up shop. When I glance over at Dana Yoerger, I’m not surprised to see he is glued to the laptop in front of him. Like most engineers, these guys are methodical. They spend hours and hours diligently reviewing data from Mesobot’s latest mission and planning out the next mission.
But right now, they are celebrating. Hayden turns his laptop towards me, and says, “check this out.” Yoerger swivels around in his chair to watch over my shoulder. He is beaming.
The source of their elation swims across Hayden’s laptop screen – thick salp chains glide through the blackness while squid zoom in and out of the frame. Marine snow, tiny krill, and phytoplankton pepper the scene. The swirl of bright, twinkling organisms looks like something out of a science fiction movie – it feels like we’re viewing the far reaches of outer space.
But this is inner space, specifically the Ocean Twilight Zone. We are watching footage that Mesobot just captured, 150 meters below us.
Hayden’s gaze is locked on the screen. “It’s like we’re sitting inside a fish tank,” he says. “Look at that ink trail from the squid!”
We watch, transfixed, as the animals continue to dart around Mesobot. We marvel at the crisp quality of the footage and the sheer number of organisms. Yoerger points out that the small fish we’re seeing are likely some of the most numerous vertebrates on the planet – but humans very rarely get the opportunity to observe them.
Eric Hayden grins like a kid on Christmas morning as he reviews the footage from Mesobot’s latest dive.
Hayden keeps a detailed log of time stamps when animals appear in the video footage.
“We need to double-check with our biologist colleagues, but we believe these are some of most abundant fish in the ocean,” he says. “We catch them in nets, but we rarely see them in their natural environment. Most technologies are too intrusive – the bigger platforms scare them away.”
But the fish don’t seem to mind Mesobot. The small, quiet, and deliberately slow-moving robot produces a minimal amount of disturbance in their habitat.
“It’s the combination of the cameras and the lights and getting to the right place at the right time,” Yoerger says. “We have layers of technology working together here.”
These technological layers started coming together during the OECI Tech Challenge aboard Nautilus in 2022, when Mesobot engineers teamed up with iXblue and engineers at the University of New Hampshire who operate the uncrewed surface vehicle, DriX.
DriX is a sophisticated platform that includes a calibrated echosounder, which can provide a bird’s eye view for Mesobot, increasing its situational awareness. At the beginning of the expedition last year, the first order of business was getting the two robots to talk to each other, and then coordinating their movements in the water.
As the communication and movements became more streamlined, so too did the potential to expand Mesobot’s capabilities. The team realized it could clearly see Mesobot with DriX’s echosounder – which could help them verify Mesobot was on target.
“We were dangling an echosounder over the side of the ship last year,” says Jordan Stanway, a robotics engineer. “It’s much better that we have one installed on DriX now.”
During the 2022 expedition, the team used that portable echosounder to determine where migrations were happening, then planned dive times around sunrise, sunset, and coordinated all those factors with ship logistics.
With Mesobot and Drix working together so well during this expedition, the dives are more efficient and generally run smoother. The team can now launch Mesobot with a template mission – go down and wait at 100 meters, then DriX will find you and give you more directions.
In short, Mesobot is a sampling platform awaiting instructions.
Jordan Stanway and Dana Yoeger run through lines of code before a Mesobot mission.
Thomas Scanlon prepares Mesobot for launch from the back deck of Nautilus.
“It’s an easier process now with a better final product,” Hayden says. “It’s simpler for us to set up the missions, and easier for us to capture events on video, and sample exactly where we want.”
This approach saves both time and potential headaches associated with writing out a detailed mission script.
“We no longer have to try to account for changing conditions during each dive,” Stanway says. “Since it’s simpler, we have less likelihood of introducing an error in a complicated mission script.”
Another new approach has worked exceptionally well during this expedition – waiting patiently in one spot.
“In the past, our idea was to drive Mesobot forward, cover more ocean, and see more stuff,” Hayden says. “But we’ve had minimal results from that.”
Stanway suggested the team should tell Mesobot to sit and wait.
“That’s what I do when I’m diving, and I want to see and hear stuff,” he says. “If you want to experience the ocean, just go down, and hang out in one place. Listen. Be a part of the environment.”
To do that, the Mesobot team sends the robot down to a specific depth – say 150 meters – and instructs it to hover in that location for the next 20 minutes. At first, the scene is mostly black, and the biology appears sparse. But very quickly, more and more animals enter the frame from different directions.
“In some places, after we had been there for 20 minutes, it was like peering through a blizzard of krill,” Yoerger says.
“But in other places, it was all salps,” Hayden adds.
While the team is excited to have captured so much compelling footage, the challenge now is to process and share the video effectively.
Going through all the video files is an immense amount of work on top of managing dive plans and operating the vehicle. Hours after I first walked into the Data Lab, Hayden is still staring at his computer screen, trying to log all the different animals he spots.
“I can’t even keep up,” he says. “There are just too many!”
I glance at the phytoplankton shimmering on his screen. “It’s a good problem to have.”
Hayden nods in agreement. “It’s an excellent problem to have.”
This feature was commissioned by the Woods Hole Oceanographic Institution and was first published in The Ocean Twilight Zone Logbook. Check out the original post here.