Beyond the desk: A week aboard a USACE dredging vessel to protect an ancient, elusive fish

Saltwater fills the coastal air among the small towns dotting Washington state’s Grays Harbor, located southwest of the Olympic Mountains. The low, steady rumble of motor vessels transiting the harbor is commonplace. For Jacqui Bergner, a U.S. Army Corps of Engineers aquatic biologist, the sound meant work, home, relaxing and more work.

One of USACE Seattle District’s primary missions is maintaining the navigation channels and harbors in the Pacific Northwest. Maintenance and navigation dredging occur frequently in harbor areas, ports and marinas. Because a significant component of Washington state’s economy relies on navigation and commerce, it requires dredging in areas like Grays Harbor. The maintenance dredging occurs along Grays Harbor’s navigation channel, which is 350 feet wide and increases to 1,000 feet over the bar.

For one week in early May 2026, Bergner called the USACE hopper dredge Essayons her home. She left behind her office’s convenience and comfort for 12-hour days sorting through thousands of pounds of sand and mud.

It was an exhausting but temporary assignment where USACE’s civil works and environmental stewardship missions merged to protect green sturgeon, a historic species that has swum among dinosaurs.

“It’s good for people to know that we have more than just engineers working here,” Bergner said. “We have archaeologists, historians and biologists across many different specialties.”

When USACE dredged Grays Harbor in early spring, the Endangered Species Act required monitoring for the accidental “take,” or killing, of threatened green sturgeon. Bergner, now in her third year of the assignment, led this critical effort for the Seattle District.

From Eelgrass Beds to the Essayons

Bergner is no stranger to fieldwork’s wet, muddy and unpredictable nature. A Chicago native who now calls the Pacific Northwest home, she spent time at Western Washington University conducting nearshore vegetation surveys for her master’s degree in environmental science.

“I’ve done a lot of fieldwork where I’ve needed to be away from home, camping and doing surveys,” she said. “I did a lot of work in eelgrass beds, walking six miles out. So, this work wasn’t necessarily foreign or unfamiliar, but it was a different arena.”

When she first volunteered for sturgeon monitoring in 2023, she stepped into that new arena with a slightly different vision of the job.

“I’m a surfer, and I thought I was going to be staying in Westport. I had this whole vision of being able to go surf after work,” she recounted with a laugh. “The reality of the assignment quickly set in during a pre-trip briefing. I was like, ‘Wait, I’m living on the boat? What is this going to be like?’ I didn’t understand.”

Her perception was shaped by images of cramped quarters and roughing it at sea. The reality aboard the Essayons, a massive hopper dredge operated by the USACE Portland District, was startlingly different.

“When I got up to the boat on the little transport vessel, I was baffled at its size,” Bergner said. “The Essayons is massive. It was built in the ‘80s, and a lot of what I’ve heard from the crew is that newer vessels are more streamlined. This vessel is not like that; you have a lot of space.”

A Day in the Life: The 12-Hour Shift

Life aboard the Essayons is dictated by the 24-hour cycle of dredging, barring pauses for maintenance and turbidity. For Bergner and her fellow monitor, the day begins before sunrise.

“We monitor during 12 hours of daylight, so the easiest way to do it is from 6 a.m. to 6 p.m.,” Bergner explained. “I wake up right at 5:30 a.m., just to make sure I am ready to go be outside all day and have coffee. And I basically roll out of bed and do that.”

When 6 a.m. rolls around, Bergner is already at her station, ready for work. The process begins with a piece of equipment called a “crab catcher” — a large basket that intercepts a portion of the dredged material before it fills the dredge’s main storage, known as the hopper.

“Part of the dredged material gets diverted up into this crab catcher, and it sifts the fine material that can flow through from the bigger, coarser material like gravel, sand and wood,” she said.

Every four minutes, the basket fills with a cross-section of the harbor floor. Then, the work begins. Bergner and her colleague sort through the pile, cataloging the aquatic life collected with the sediment.

“Sometimes you’ll have shrimp, sand dollars, jellyfish, or other types of fish species and aquatic organisms,” she explained.

They’re monitoring for something much larger. Green sturgeon can weigh up to 350 pounds and stretch over seven feet long. They are ancient, armored fish. Bergner knows the objective: look for signs that the dredge accidentally killed one of these giants.

If a specimen looks like it came from a large fish, aquatic biologists treat the piece of flesh or bone fragments as a potential sturgeon. “Anything that looks kind of suspicious, like a big dead fish, we typically take a tissue sample of that,” she said.

Each sample is carefully cataloged and labeled. By cross-referencing the corresponding hopper number and the Essayons’ GPS data, the team can determine the sample location with pinpoint accuracy.

"The tissue samples are later sent to the USACE Engineer Research and Development Center in Vicksburg, Mississippi, for DNA analysis. There, scientists can identify the species of the sample, determining whether green sturgeon “takes” occurred during dredging activities. These results are reported to the National Marine Fisheries Service to ensure USACE complies with the Endangered Species Act.

The sifting-and-sorting cycle continues throughout the day. But even a hardworking crew needs to eat. “The meals were always my favorite part of the day,” Bergner said. In between breakfast, lunch and dinner, 45-to-60-minute breaks occur when the Essayons travels to its designated offshore site to dispose of the dredged material.

During these lulls, Bergner might catch up on administrative tasks, enjoy a cup of coffee, or simply reset before the next round of sampling. After the 12-hour shift ends at 6 p.m., the exhaustion is real. “Typically, both of the monitors are exhausted,” she said.

Evenings are spent exercising in the onboard gym, walking laps around the deck with a podcast playing, or simply reading. “I got through like two books,” she said of her most recent trip. Then, it’s a short night’s sleep before the 5:30 a.m. alarm signals the start of another day. “You rinse and repeat for seven days, essentially.”

A Team of Teams

While Bergner and her Seattle District colleague are the biologists onboard, they aren’t alone. USACE employees from across the agency make up the Essayons mariner crew. There’s a chef from New Mexico, a mechanic from Mississippi and dozens of others supporting the dredging operations.

Observing the vessel’s crew in action gave Bergner a profound appreciation for USACE’s sheer scale and diversity of expertise.

“It’s really cool to be with the crew and to hear about what their experience is working for USACE, because they’re doing such a different thing than what we do in the office,” she reflected. “We’re working for the same agency, and they’re doing more of the action, and we’re doing more of the operations, planning and management of that action.”

The Essayons crew are jacks-of-all-trades. They possess the required skills needed to keep a massive, complex machine running 24/7 in a sometimes-harsh marine environment.

“The people that work on the Essayons are so trained. They take safety so seriously,” Bergner emphasized. “Many of them are trained firefighters, because you must be able to fight a fire on the boat. I’ll see them gear up for drills and wear fire suits.”

The readiness culture and constant maintenance ensure the dredge can perform its vital navigation mission safely and effectively. For Bergner, seeing USACE’s operational side firsthand was a reminder of the organization's depth.

“Something I’ve learned being at the Corps of Engineers is just how much expertise there is in all of these different domains,” she said. “We have technical experts across so many different fields, and we all get to work together towards a common goal. People are so good at what they do, and it’s really an honor to be working here.”

The Mission Behind the Mud

Bergner’s work perfectly reflects Seattle District’s Planning, Environmental and Cultural Resources Branch. This diverse group of biologists, archaeologists, historians and environmental scientists provide the technical expertise needed to ensure USACE projects comply with the nation’s most important environmental laws.

“Doing things like this green sturgeon monitoring is part of that project implementation, where we're working on a project that's actively happening to ensure that certain things that need to happen, continue to,” she said.

This commitment to environmental stewardship is woven into the fabric of every USACE project, from dredging and navigation to flood risk management and ecosystem restoration. For Bergner, the opportunity to experience the many diverse missions is fulfilling and meaningful.

“Even in my three years of being at the Army Corps, I have performed wetland delineations, I've done surveys for submerged aquatic vegetation like eelgrass, I’ve done surveys looking for bugs, and I have done green sturgeon monitoring and gravel surveys,” she listed. “It’s a dream for an environmental scientist to be able to do so many different types of things.”

Bergner’s week aboard the Essayons is about more than just fulfilling a legal requirement. It’s a tangible expression of USACE’s commitment to balancing its critical engineering and civil works missions with the solemn responsibility of protecting the nation’s natural treasures.

Despite the early alarms, the constant rumble of the dredge and the endless sifting through mud and sand, Bergner isn't ready to give up her spot aboard the Essayons just yet. When asked whether she’ll be back aboard next year, she responded simply, “I don’t see anything stopping me.”