R/V Ocean Starr retrieving a bottom beam trawl on the Beaufort Line station at a depth of more than 300 meters!
The Beaufort stirs with excitement. Ocean water travelling from the Gulf of Anadyr, Russia, and the Bering Sea smushes and bruises—both very technical terms—into the Arctic, zipping over Barrow Canyon and hugging Alaska’s continental slope. Along for the ride are micro and macronutrients riding the flow like an underwater locomotive (I’m thinking like the Polar Express…and yes…I have a three year-old daughter so most of my recent analogies stem from children’s books) after being advected from 50 meters below. Krill and other euphausiids feast on the plankton smorgasbord. Bowhead whales careen the coast with mouths agape filtering sea water and trapping larger zooplankton and larval fishes. A euphony of species competition, predation, growth, and deposition are all on display in the Beaufort underneath the turbid waves and grey façade. The Beaufort has been waiting for us, like a dog wagging its tail anxious to greet its new visitor.
A mild breeze touches the faces of those on the back deck of the R/V Ocean Starr, a sharp contrast to the focused countenances fixed with tense jaws and furrowed brows. The deck is adorned with trawl gear and bongo nets, tools to fish for creatures living beneath the visible depths. There is a general buzz on the back deck as more science and vessel crew have descended upon the narrow stern of the ship.
The new vessel crane operator, John, inspects the trawl gear. Normally in the crane box slinging our research moorings over the side like a boss, John has found a new role in the trawl operations. He has fished for most of his life for tuna, mahi mahi, and swordfish all over the Pacific. So a beam trawl is a walk in the park for him. Already, he has started modifying the gear to make it easier to bring aboard. Holding a fid and a line, he methodically snakes the line over and under the netting like sewing a giant blanket. Hard hat, life jacket, hoodie, shorts, and flip flops, John taunts the Beaufort with his acclimated physiology. In a matter of minutes, John has fixed a new hand loop to pull the beam gear up and over the trawl ramp on the stern of the ship.
Libby Logerwell surveys the trawl gear splayed out on deck. Sarah Donohoe and Pete Shipton inspect the shackles holding the net to the horizontal steel pipe in place. The ship’s A-frame is moved inboard in preparation for the beam trawl deployment. Manning the gears is the Ocean Starr’s youngest AB, Austen—an eager, hardworking young man from Astoria. David Strausz and Catherine Berchok man the winch that will drop the gear to the bottom of the ocean. Careful, methodical, and extremely calculated, the crew prepare their final checklists before deployment. If it sounds like the crew is extra careful, well—hopefully that has been conveyed.
The Ocean Starr approaches the station location on the GPS display. Captain Pete eases the pneumatic levers controlling the main engines. A soft whish emanates from the levers knowing the engine has lessened its load. That whish sound is one of the most distinctive sounds on the ship. In all the years I have worked on ships, I have never heard that pneumatic air sound that controls the main engine.
Libby heads back into the lab to check the depth. Three hundred meters—the deepest depth we have sampled on this leg. Based on the CTD that descended earlier to these depths, the water is super cold at the bottom, -4°C. A few last-minute calculations and confirmation of the seafloor topography from the ship’s fish finder, Libby comes back out on deck. The seafloor looks ideal for deployment. The crew hustle to their deployment positions.
Controlling the A-frame, Austen starts to walk the gear outboard, dragging the heavy net and weights on deck towards the trawl shute. David Strausz eases the winch cable, and in a matter of seconds, the gear exits the stern of the ship like the Jamaican bobsled team. The cable descends at about 3m/s. At a 1 1/2 knots, the vessel moves slowly and methodically as hundreds of pounds of gear and cable navigate to the Beaufort seafloor. Everyone on deck starts postulating what type of creatures will be brought to light.
“Maybe we’ll catch a sleeper shark,” I reply coyly. Haley Cynar, who was helping with filming the operation, smiles slightly. We both know that catching something like that would be extremely rare and downright crazy. What was I thinking?
But as the cable descended to the bottom, I could only think that everyone else was imagining the same type of wonder that I was. All of a sudden, the cable slackened. We reached the bottom.
For five minutes, the Ocean Starr dragged the bottom trawl across the seafloor bottom; an eternity for those on deck. And as the cable started to reel in, what Libby didn’t know was that what we caught would surprise even her.
“100 meters,” Dave trumpeted over the sounds of the winch cable, main engines, generators, and crane. The anticipation is building. Soon the trawl bar peeks at the surface with the net bouncing along in the waves. The beam trawl has surfaced, and with a full net full of….
Mud. And brittle stars. Thousands of brittle stars and enough mud for every crew member to make the best sand castles. There were a few adult snow crabs, but mostly juvenile pinchers grabbing ahold of Sarah and Haley’s gloves. An adult crab grabbed hold of both of Jordi’s blue fishing gloves crippling his ability to subsample the haul. But don’t forget about the mud. Muddy boots, muddy Grundens, and muddy faces all gathered around the fish box to see what lay on the Beaufort seafloor.
Libby Loggerwel explaining about the ocean currents moving into the Chukchi and Beaufort Seas.
And why was this haul somewhat surprising for Libby? Well, due to the currents ripping through the continental slope where we were sampling, she expected the substrate to be different than the muddy bottom as well as more adult Arctic cod in the beam trawl. The bongo net deployment she did afterwards only confirmed her suspicion. Where she was hoping to find large abundances of larval Arctic cod, the bongo came up empty handed. In 2018, Libby and her team sampled larval and adult Arctic cod in the same region where we just sampled. According to her, larval cod are expected in the Hanna Shoal, Barrow Canyon, and Beaufort. Perhaps the our team just missed the honey hole.
“It’s only one sample,” Libby replied when I asked her about what she thought about the trawl and bongo results. “We need to sample more to get a better idea of what’s really going on down there. One trawl and bongo at this station is just not enough.” But time has run out for the crew on Leg One and our journey back to Nome is upon us.
The next day, I sit down with Libby to review a paper by Seth Danielson, Lisa Eisner, Calvin Mordy, Carol Ladd, Leandra Sousa, and Thomas Weingartner. Admittedly, she noticed that I was incorrect with some of the currents previously described. But our conversation turned to the vast expanse of the Arctic and where she thought the cod might be. I was reminded by Franz Meuter’s model of Arctic cod spawning grounds south of the Beaufort and asked Libby why adult Arctic cod have not been sampled in between the spawning grounds and the sample location we just finished in the Beaufort.
“It’s a mystery,” Libby reflects. “We have definitely caught adult Arctic cod in the area, but the numbers are just not enough to account for the amount of juveniles we find.” Sounds like a mystery definitely worth trying to uncover.