Mission: Acoustic Trawl Survey (Leg 3 of 3) Geographic Area of Cruise: Pacific Ocean/ Gulf of Alaska Date: Friday, August 18, 2023
Weather Data Lat 58.18 N, Lon 148.82 W Sky condition: Partially Cloudy Wind Speed: 10.55 knots Wind Direction: 32.58° Air Temp: 14 °C
Science and Technology Blog
Meet Sandi Neidetcher, she is a fish biologist investigating fish reproductive status. Why care about fish reproduction? Well, the seafood industry is extremely important to Alaska and other coastal states. And they would not have an industry if those “little fishes” could not reproduce. But the ocean is changing due to climate and different types of pollution.
Climate change is making our oceans a warmer place—just a couple of degrees, but that may be enough to really change how fish reproduce and spawn. A few degrees in temperature could change when and where fish reproduce, and then cascade to the fishing industry, the food market, and the people who depend on them as food.
NOAA wants to have background information on fish reproduction so they can recognize whether the fish have changed their reproductive strategies over time and how that could impact fisheries.
Sandi received her Masters degree studying the ovaries of Pacific cod to determine the phenology and geography, or the timing and location, of spawning. She specialized in histology, which is the study of microscopic tissue structures, for her it was specifically the ovaries. To understand the reproductive process and ovary maturation, she studies slides with ovary tissue mounted and stained to show oocyte (unfertilized egg) structures that develop as the spawning season progresses.
Examples of histograms from Sandi’s research, showing the progression of Pacific cod oocyte structure development over the course of the spawning season
Now she is involved in a study looking at the reproductive states of Walleye Pollock. Pollock are multi-batch spawners. They have the ability to spawn (lay eggs) more than once in a season. So the female ovaries can be in different stages of reproduction throughout the season.
The first step in this analysis is to collect the ovaries from the pollock.
Sandi Neidetcher and Robert Levine work together to collect data on a pollock.
In the photo above, the fish will be measured for length and weight, then the ovary and the liver will be removed, weighed, and saved for analysis. The fish’s ear bones (otoliths) will also be removed and used to determine its age. Samples are sent back to Sandi at NOAA AFSC (Alaska Fisheries Science Center) in Seattle, Washington. Half of the ovary will be sent to a histology lab where technicians will prep the tissues and return the sides ready to be analyzed. The other half of the ovary is scanned on the ship.
Sandi is comparing the histological samples to Raman Spectroscopy Analysis that she does aboard the OscarDyson. A long time ago when I was an undergraduate student in chemistry, Raman spectrometers were very large. The one I worked with in my physical chemistry class was in the basement of a building on a special concrete slab that stopped any vibrations from disturbing the path of the laser. Did I mention that the whole setup took up almost half of the basement?
The computer displays a scan of the ovarian tissue
Raman spectrometers have come a long way since my undergrad. Today, Sandi has a small wand that contains a laser connected to a spectrometer the size of a donut box. A small desktop computer connected to the spectrometer will give an immediate readout of the analysis.
The wand with the laser is held over the ovary to collect data on large macromolecules like lipids, proteins, and DNA.
You can see the laser light as it penetrates the ovary.
The analysis that Sandi does is to compare the molecular composition identified through the spectral patterns with the structures seen in the histology samples, and to determine if the maturation status can be identified through the spectral patterns. The ultimate goal would be to have a small hand-held spectrometer that a scientist could use right as the ovaries are extracted. This would greatly increase the amount of ovaries analyzed quickly and efficiently and reduce the cost and time required for histological analysis
Sandi at her work station on the Oscar Dyson
Pollock have variability in their reproductive strategies and may be impacted by environmental conditions. One strategy is down regulation, where a fish will reabsorb a number of eggs during maturation and, as a result, reduce the resources spent on reproduction. This reduces the fecundity, or number of eggs released by that fish in a season. Knowing how fecund a fish population is helps managers determine how many fish can be removed by a fishery. Atresia is the resorption of an oocyte and can be seen histologically. Mass atresia is where a whole ovary of oocytes is be reabsorbed. If the fish is not finding enough food or the temperature is not correct then, then a female fish can save energy by reducing, or stopping the whole process of reproduction.
Recent warming sea temperatures have been seen in the Gulf of Alaska, and this may be impacting fish reproduction. In 2020, the number of Pacific cod predicted had dropped so low that the federal waters fishery was closed. That same year, crew fishing for Pacific cod reported seeing a number of Pacific cod with mass atresia. Scientists do not know if the observation of atresia, during a warming period, is related to the population crash but studies like this will give more information for the future. Predicting population crashes that may be related to climate change, fish health or temperature differences are an important part of fisheries management and impact us all because the ocean is an important resource.
Personal Blog
Crew Members in the Spotlight
Pictured left to right, Juliette Birkner – Engineering, and Ben Boswell – Survey Technician
The Commanding Officer runs the ship, but there are many important jobs that the OscarDyson would not function without. Engineering is one of them. There is a small team of Engineers aboard that are constantly monitoring the ship when on shift.
Juliette is a member of the OscarDyson’s Engineering department and may have been on the staff the longest. Her personality is direct, friendly and capable. Before becoming an Engineer, she attained her bachelor of science degree at the University of Washington. After receiving her degree she did not really have a clear plan for a job. So she went to a community college and received the equivalent associates degree of a Junior Unlicensed Engineer. Eventually, through NOAA, she can be a fully qualified Engineer with time aboard ships.
Juliette has a wildly creative side and interest in science. The scarf she is wearing in the picture has different layers present in sedimentary rock. She is also a big fan of dinosaurs, placing several all over the ship for people to find when work is slow. Honestly, it is the kind of humor that keeps everyone moving around with a smile. Some dinosaurs even have sweaters that she knitted, in her down time. Her knitting is extremely impressive.
Ben is the Survey Technician for the ship. Survey Technician is the kind of job you would never know exists as a high school student. There are jobs out there in this world that people would never specifically train for in high school or college , but are highly needed where you have different groups collaborating in complex situations. Ben’s job description is a pretty long list; calibrate scientific instruments, collect data, assist scientists, help the deck crew, and act as a liaison between science and the deck crew.
How did he arrive at this position? He attained a bachelor of science in Wildlife Biology and worked in the field for a while. Unfortunately, he found the job hard to make a living with the low pay. Fishing’s siren song came in the form of factory trawling and other crew positions in smaller boats. Because of his academic training and work experience the “perfect storm” of a Survey Technician was born.
Soon we will be taking our last trawl sample and heading to port in Kodiak. There have been moments on the cruise where time crawled in the dead of night while I was struggling to stay awake. Mostly, it has been a trip of a lifetime, with an incredibly capable and adaptive team of scientists and crew members willing to share stories that keep you awake and lull you to sleep, dreaming about tomorrow.
Mission: Pacific hake (Merluccius productus) Survey (Leg 3 of 5) Geographic Area of Cruise: Pacific Ocean off the Northern California Coast working north back toward coastal waters off Oregon. Date: Monday, August 14, 2023
Weather Data from Portland, Oregon Friday, August 11, 2023 (one week from our final trawl) Sunrise 6:06am PDT | Sunset 8:24pm PDT Current Time: 2:53pm PDT Location: 45. 59578° N, 122.60917° W (Portland International Airport) Visibility: 10 miles Sky condition: A few clouds Wind Speed: 6.8 mph Wind Direction: NW Barometer: 1016.80 mb Air Temp: 82° F Relative Humidity: 37% Speed Over Ground (SOG): 0 knots as I sit on my front porch at home! Willamette River water temperature: 74°F
Monday, August 14, 2023 Sunrise 6:10am PDT | Sunset 8:19pm PDT Current Time: 2:53pm PDT Location: 45. 59578° N, 122.60917° W Visibility: 10 miles Sky condition: Clear Wind Speed: 10 mph Wind Direction: WNW Barometer: 1010.10 mb Outdoor Air Temp: 105°F (record ended up at 108°F) Relative Humidity: 21% Indoor Air Temp: 78°F (our AC consists of several Doug Fir trees) Speed Over Ground (SOG): 0 knots as I sit at my computer in my home office space. Willamette River water temperature: 75.02°F
Science and Technology Log I’ll start my last blog post with some vocabulary… and a sports analogy. Apologies in advance, I’m testing out some sports jokes to appeal to my 5th-grade sports fans who are skeptical about science. My hope is that the vocabulary (at least) will aid in understanding the following narrative about NOAA Ship Bell M. Shimada’s Leg 3 centerboard retraction.
Don’t worry, it’s not too complicated. It isn’t that different from how rookie Trail Blazer Ibou Badji (Center) was removed for knee surgery at the end of last season… or how the other Center, Jusuf Nurkic, was ejected after an altercation with an opponent and then retracted for the remainder of the same season with plantar fasciitis… Where have all the Centers on the board gone? At least there is more certainty of Shimada’s centerboard returning than Nurkic (even though he has three years on his contract left)!
Vocabulary
Acoustics – In our case, acoustics refers to an entire branch of physics concerned with the properties of sound. Yes, acoustics can also refer to how your voice sounds when singing in the shower.
Sonar – A system for the detection of objects underwater by emitting sound pulses and detecting or measuring their return after being reflected by the objects. The vocabulary words that follow are all related to the sonar system on the Shimada.
Centerboard – A retractable hull appendage, similar to the keel on a sailboat.
Ping – To emit a signal and then listen for its echo in order to detect objects. Sean Connery may have introduced you to the concept. “Give me a ping, Vasili. One ping only, please.” (Captain Ramius, The Hunt for Red October, 1990)
Hertz – One hertz (Hz) is equal to one event per second. The unit’s most common usage is to describe periodic waveforms (as is used in acoustics) and in musical tones. Kilohertz (kHz) is equal to 103, megahertz (mHz) is equal to 106 .
Transducer – A device that converts variations in a physical quantity, such as sound, into an electrical signal, or vice versa. On the Shimada, the transducer emits a ping.
Transceiver – A device that both transmits and receives communication. There are five transceivers on the Shimada, one for each frequency—measured in kHZ—that the scientists monitor. Walkie-talkies are one example of transceivers.
Note: I have a habit of calling things by their incorrect names, and had some confusion about how a “transponder” fits into these “trans” terms. A transponder is a blend between “transmitter” and “responder.” Essentially, a device that receives a radio signal and emits a different signal in response. They are used to detect and identify objects. If you have a car key fob that locks and unlocks your doors remotely (or starts your engine), then you are walking around with a transponder. Transponders are also commonly found in airplanes.
Echosounder – A type of sonar. The Shimada uses a wideband transceiver (WBT) scientific echosounder system for the hake survey.
Echogram – The visualization of sound once the transceiver “listens” to the acoustic return pinged off objects.
Cleaning up is often a sign of good things coming to an end. Whether it’s scraping glitter glue off the tables of my library, or fish scales off stainless steel in the Shimada, both signal the end of a productive work period. On Friday night, August 4th, the Wet Lab crew conducted a deep clean of the space after the last trawl. On Saturday, the net was streamed one last time (for Leg 3 anyway) on our way back to Newport, Oregon. Creatures like pyrosomes, flatfish, and young-of-the-year (YOY) hake that had been stuck in the net were flushed out after a period of time waving goodbye in surface waters. YOY is used interchangeably with the term “fingerlings” in the vocabulary of fish development.
In which I get to “swab the deck”… or swab the baskets in this case.
Another event that occurred Saturday was the raising of the centerboard. The centerboard is always raised at sea and cleaned once in port. “Biofouling mitigation” is the fancy term for centerboard cleaning. This is to ensure sea life, such as barnacles, do not adhere themselves to the surface. A build-up of these stowaways could interfere with the sonar. Hmm, I sense potential here for another sports analogy… something about fouls.
The Survey Crew coordinates with the bridge and the engineers to retract the centerboard. Transducers are mounted on the centerboard so they can be lower than the hull. This reduces bubbles and noise. In the Shimada’s case, bubbles are air pockets created by the movement of the ship’s bow. A centerboard extends the distance between sonar equipment and the activity of bubbles gathered near the hull. When seas are rough enough there can actually be a data dropout that appears as a white line on the echogram.
Elysha Agne, at the centerboard control panel.
Fully extended, the centerboard is 3.4 m below the hull of the ship and 9.15 m below the baseline sea surface. There is a manual option for retracting the centerboard, but it is generally only used if there’s a problem. Automatic operations are the norm, and were used when I observed the procedure.
Officers on the bridge slow the ship to 0 knots. The bridge confirms with survey technicians which position the centerboard should be moved to. A control panel for the centerboard is located one deck below the acoustics lab. I stood with Senior Survey Technician, Elysha Agne, to observe the process for retraction. NOAA Corps crew actually push the button on the bridge for retraction, but Agne communicates over the phone with them to confirm what the centerboard control panel is indicating.
Barnacles on a Shimada transducer after three legs of the 2023 hake survey. Photo taken by Elysha Agne.
Just down the passageway from the control panel are the double watertight doors that provide access to the instrument pod on the retracted centerboard. I include a picture of these doors in the Hook, Line, and Thinker section of blog post, “Let’s Get Specific in the Pacific.”
Once the button is pushed and the centerboard is ostensibly moved, Agne confirms the indicator lights on the control panel and looks through the porthole on the watertight doors nearby to confirm the white letter “R” (for “retracted) is visible on the appendage. Agne turns off the transducers (no pinging) before retraction starts in case the transducers accidentally go out of the water.
This is important because sound travels differently through air than in water. If the transducer were still pinging while a crewmember had their head through the open centerboard access doors—that wouldn’t be good for human ears. The transducer can actually be damaged beyond repair if it pings in the air. The centerboard actually has holes in it, so it fills with water when lowered, then drains as it is raised. I could hear the water draining during the retraction process.
Career feature
CO Slater at one of Shimada’s gyro repeaters.
CO Slater sits in his Captain’s Chair and inspects the horizon.
Joshua Slater, CO (Commanding Officer) Give us a brief job description of what you do on NOAA Ship Bell M. Shimada.
I’m responsible for the safety of the ship and its 41 crewmembers (depending on the voyage), including safe navigation, accomplishment of science missions, project management, budget, personnel, and training of the crew.
What’s your educational background?
I have a Bachelor’s in Marine Biology and a Master’s in Marine Sciences both from the University of North Carolina, Wilmington. I grew up in a Navy family, so we moved all around the world. I don’t consider one place home over another. After graduation, I wanted to go to either California or Hawaii. I got a job as a contractor with NOAA doing free-diving and scuba in Hawaii as a Marine Debris Technician. I removed derelict fishing gear and nets off the coral reefs of the northwestern islands. I joined NOAA Corps after that. I attended the U.S. Merchant Marine Academy in King’s Point, New York. In the Corps, there’s a 2:3 rotation ratio in years spent on assignments at sea and on land.
I started out on NOAA Ship McArthur II. We sailed from Seattle out to Hawaii, down to South America, Mexico, and up the West Coast of the U.S. to Canada. My assignment after that was emergency response for incidents at sea such as hurricanes and chemical spills. One of those projects was on the Deepwater Horizon oil spill response down in the Gulf of Mexico. My next ship was in South Carolina on NOAA Ship Nancy Foster, where I worked from Massachusetts to Key West, to Galveston, Texas. After that were land assignments in Washington DC, then Chief of Operations at NOAA’s Marine Operations Center for the Pacific (MOC-P) in Newport, Oregon. I’ve bounced between MOC-P and the Shimada in that land-to-sea ratio since then.
In the NOAA Corps, you start out as an Ensign (pronounced “en-sin”). Within 2-3 years you usually get promoted from ensign to Lieutenant junior grade. During your first sea tour, you need to learn how to drive the ship, keep everyone safe, and understand the basics of ship operations. During your second sea tour, you help coordinate logistics for operations. On the third sea tour you’re running all the administrative functions (hiring, firing, discipline), and on the fourth time out hopefully you are experienced enough to be considered for the ship’s Captain, overseeing the safety of the whole ship, and making sure operations are done efficiently. So, as you work your way through your career you also get promoted. Beyond the rank of Lieutenant junior grade, there’s Lieutenant, Lieutenant Commander, Commander, Captain, and then Admiral.
For civilians, Ship Captain and CO may be viewed as interchangeable. In NOAA Corps you can be a commanding officer and be any number of different ranks. In the civilian world, the ship’s boss is called “Captain” or “Master.” Since NOAA Corps stems from military origins, they use “Commanding Officer.”
What took you by surprise about sailing on the ocean?
What took me by surprise was the amount of operations we could do in less-than-ideal weather. You might have a calm day on shore, but at sea it’s usually windy and you have waves of some sort. We do the best we can given the situation.
Why are conditions rougher further out at sea?
A few things. Currents. Wind. Sometimes headlands protect you from wind when you’re closer to shore. How big the waves get is a combination of how strong the wind blows, how long it blows, and over what distance of water. That’s called the fetch. That gives the time needed for the swell to fully develop based on the wind. Wind at a short distance is a wave. Once you get beyond where the wind is that localized phenomenon, further away it’s the swell. While our wind may be calm here, we may still have a big swell because there’s a storm off Hawaii or Alaska. We’re not feeling the wind but we’re feeling the side effects. Or we could just be in the wind, it’s blowing 50, and not that bad right now, but give it 12 hours to develop, 24 hours, and it’s going to be a lot worse. You do what you can given what you have to work with. The ship is seaworthy and can handle a lot of different conditions.
What’s the biggest weather you’ve been in on the Shimada?
Probably 20-foot waves, although waves are not consistently one height, they’re a range. They may be normally 16-18 feet, but you might get a 22-foot wave come through. The ones I’ve been in consistently were about 20.
At what point is it not safe to conduct operations?
It depends what the wind is, what the swell is, whether they’re from the same direction or opposing directions, or 90 degrees off. Sometimes our whole project is in the trough, which means the waves are hitting us from the sides, so we’re rolling a lot. The way transects are laid out for trawling and sampling gets us rolling a lot. If it’s really bad we’ll angle our way from one location to another. We do have safety standards for operations. Once the wind is above a certain limit, or the waves above a certain range in height, we’ll reassess. Usually, we reassess the operation if wind is over 30 knots, but we’ve done ops in 40 knots before. We’ve also done ops in 16-foot waves. There are a lot of variables to be considered, including the type of operation we’re attempting to execute.
We’ll get people who have never been out here before, or we’ll get people that are so focused on the science, they don’t think about safety. My job is to make sure they don’t forget about safety! We have a daily safety meeting of department heads on the ship. There are weekly drills at sea. During monthly safety meetings, we go over accidents in the NOAA fleet. It’s a lot easier to learn from other people’s mistakes. We all want to come home with our fingers and toes!
What advice do you have for a young person interested in ocean-related careers?
Grow where you’re planted. In NOAA Corps, you don’t get to necessarily choose the jobs where you go next. A board of officers chooses for you, based on your skill set and the needs of the service at that time. For example, I can list my preferences, but there’s no guarantee I will get any of them. There have been many times where officers haven’t even received their second or third choice. My advice to everyone is, you may not want to go to a particular assignment or a particular part of the country, but you’re there, so make the most of it. Every place I have been assigned has good qualities, good things to offer. Those are what I choose to focus on. When I talk to some people, they never seem happy no matter where they are. I think that is a mindset issue. One of my favorite quotes is, “Positivity is a superpower.” The term “Shimada-tude” got its start in the early days of the ship’s service to NOAA and is all about positivity. We want to like what we do and want people to like coming out to sea. We want them to have a good experience, and treat everyone with respect.
Do you have a favorite book?
Growing up I often looked for the Newbery Prize Medal seal or the Newbery Honor seal on a book cover when I was walking through the library. I figured if somebody liked it I might as well try it. It’s hard to pick just one book. I tried a lot of the classics and have made my way through most of “The 100 Greatest Books Ever Written.” Some were enjoyed while others were not. I remember taking an interest in The Odyssey and The Iliad, by Homer; Robinson Crusoe, by Daniel Defoe; Shipwrecked, by Robert Louis Stevenson; The Phantom of the Opera, by Gaston Leroux; and Dracula, by Bram Stoker—to name a few.
Lately, I’ve been reading more and more about financial education. One book I recommend is The Richest Man in Babylon, by George Samuel Clason. It uses fictitious ancient parables to give you sound monetary advice, and that is something that I don’t think is really taught anymore.
As for children’s literature, I’ve recently read a few of the Harry Potter books with my son. I remember reading and enjoying The Chronicles of Narnia series, by C.S. Lewis, Island of the Blue Dolphins, by Scott O’Dell; and Where the Red Fern Grows, by Wilson Rawls.
Floating (Food) Facts (& Opinions)
Here’s the part where we “Let them eat hake.” If you can get your hands on some hake through a company like Pacific Seafood (headquartered in Clackamas, Oregon), then you can decide for yourself whether all this fuss over hake is worth the hype.
Hake (Pacific Whiting) is the most abundant commercial stock on the Pacific Coast.
If you aren’t into hake but consume other seafood, use Fish Watch. NOAA Fisheries hosts sustainable seafood profiles with current information on marine fish harvested in the U. S.
The first couple of paragraphs on the Fish Watch site define “sustainable seafood:”
“Sustainable seafood is wild-caught or farmed seafood that is harvested or produced in ways that protect the long-term health of species populations and ecosystems. The United States is a global leader in sustainable seafood. U.S. fishermen and seafood farmers operate under some of the most robust and transparent environmental standards in the world. If the seafood you purchase is caught or farmed in the United States, you can feel confident you’re making a sustainable seafood choice.
Marine wild-capture fisheries in the United States are scientifically monitored and regionally managed. They are enforced under 10 national standards of sustainability through the Magnuson-Stevens Act—exceeding the international standards for eco-labeling of seafood.”
You may have stood in front of the seafood counter and noticed those green (best choice) and yellow (good alternative) labels. I have yet to see red, which means avoid, which seems counter to the marketing impulse of grocery stores. These labels are based on the Monterey Bay Seafood Watch guidelines. Here’s a pocket guide for my West Coast friends. There are a handful of seafood guides you can consult, but not all are created equal. This article from 2017 captures the frustration consumers sometimes have about what fish to choose.
Part of my confusion is often based on the many names a single species has! For example, I just now learned (on the NOAA Fish Watch site) that Bocaccio are rockfish and are the Oregon Red Snapper I recall from shopping trips and meals as a kid. For me, the thing that makes NOAA’s Fish Watch site superior to the rest is the comprehensive overview of each species profiled. You get detailed sections on Population Status, Appearance, Biology, Where They Live, Fishery Management, and Harvest all in one place. Bon appetit!
Image of a hake with nutritional information from American Seafoods.
Fog persisted on our steam north back to Newport. Without the temptation of visibility on the flying deck, I took extra time vacuuming the stateroom… that’s a joke because vacuuming a 4-person stateroom takes all of 5 minutes. In truth, my roommate and I took care to leave our space Pine-Sol fresh for Leg 4. After packing away my gear I bounced around the ship like you might in a hotel room—surreptitiously checking drawers for items you may have forgotten. That last nautical mile seemed to take forever. I kept looking out of the portholes in the acoustics lab to see nothing but white. Excitement for home began to build once it was time to gather on the flying deck and peer through the misty water vapor. Yaquina Bay Bridge slowly materialized, an elevated street floating in the sky, weirdly disembodied from the solid ground that usually frames it. As we went under the bridge the fog disappeared. Beyond, an 80° Oregon summer in the Willamette Valley beckoned. The Wet Lab Crew ate dinner together while the crew of the Shimada safely docked and worked with the port crew to reattach the gangplank. After hugs and handshakes all around it was time to part. My drive home was uneventful save a dramatic sky.
A HUGE thank you to the Shimada crew aboard Leg 3! You welcomed me, answered my questions, allowed me to look over your shoulder, tolerated me taking photographs of you, and clarified things I didn’t understand. You all are amazing. I appreciate your labor and am thrilled to have witnessed you all working in sync to do science! My students at Peninsula thank you as well—even if they don’t know it yet. Your time and attention will enhance not just one, but many ocean-related lessons I share with them in the forthcoming year. A special thanks to my blog editors: Chief Scientist Steve de Blois and XO CDR Laura Gibson. Your feedback polished these meanderings and gave me confidence that I correctly represented NOAA and the hake.
You Might Be Wondering…
What Next?
To complete my commitment to NOAA as a Teacher at Sea I agree to blog, write one science-related lesson, one career-related lesson, and either present at a conference or publish an article about my experience. I’m back in my school building this week and will soon be working on lessons. At least part of the science lesson will follow the path of hake otoliths (ear bones) from the ocean to the lab back on land. Many thanks to Liz Ortiz, Fisheries Technician, for helping me connect the dots on how the otolith contributes to our understanding of Pacific whiting (hake) life cycles. I’ve decided to publish an article, although I will likely also present at a conference in years to come. I have reviewed children’s books for the national journal, School Library Connection, since 2011, and will start my query for publication there.
The sky was blue when we left Yaquina Bay on Day 1, not so on Day 14.
A brief video reflection of Leg 3.
Hook, Line, and Thinker
Do you eat or consume products harvested from the ocean? Where do those products come from?
If the country of origin for products consumed isn’t the U.S. does that country have an equivalent of NOAA that gathers data and prioritizes sustainability in its policies? For context, consider this recent article from NPR: Demand for cheap shrimp is driving U.S. shrimpers out of business. I’m doing a homemade pad thai recipe this week and reading this motivated me to pay attention to where my shrimp came from. All the shrimp choices at Fred Meyer (Kroger) were imported so I went elsewhere (paid more) and found some from the Gulf of Mexico, harvested in U. S. waters.
While you’re eating your own pad thai with U. S. shrimp, or Pacific whiting mac ‘n cheese, consider NOAA Fisheries first-ever National Seafood Strategy, just released on August 9th, 2023.
A Bobbing Bibliography: Reflections of a Librarian at Sea
Additions to the Science Crew’s Reading Recommendations:
Chris Hoefer, OSU marine mammal & seabird project – The Three-Body Problem, science fiction by Liu Cixin (Scientific Americanarticle about the concept behind the name.)
Samantha Engster, eDNA Scientist – The Shell Collector, short stories by Anthony Doerr
***
Parting thoughts from your Teacher-Librarian at Sea as inspired by quotes from a few children’s literature classics.
“Look at that sea, girls—all silver and shadow and vision of things not seen. We couldn’t enjoy its loveliness any more if we had millions of dollars and ropes of diamonds.” ― Lucy Maud Montgomery, Anne of Green Gables
In my current reading of this quote, I can’t help but immediately extract the tension between commerce and being. It seems to be a theme I have returned to again and again throughout my blog posts. To be, to exist on our planet, is dependent on a healthy ecosystem, and a healthy ocean. NOAA Fisheries leans on the scientific method to tackle a barrage of pressures: consumer demand, climate change, economic prosperity, pollution.
We would do well to remember that NOAA is made up of ordinary people. The government, by the people and for the people. Many of these you have met in my interviews. I was at a dinner party recently (since I’ve returned to land) and there’s always someone in the crowd who makes half-joking remarks about “the government.” What? You killed fish in the name of science? What? Do the fisherman have the same opportunity to trawl? C’mon. Who do you think “the government” is made up of? Your uncle with a Ph.D. in physics. Your daughter with a passion for birds. “Things not seen,” are confusing, intimidating, sometimes scary. NOAA is utterly transparent. The amount of unfettered data available for citizen scientists to freely examine on the internet is mind-boggling. Keep asking questions, then ask more questions! Then do some research—ask a librarian for help!
“The sea, the sea, the sea. It rolled and rolled and called to me. Come in, it said, come in.” ― Sharon Creech, The Wanderer
It said “Come in” the loudest when smooth and glassy. While there were no swimming opportunities on board the Shimada, I have since returned to swimming at my local health club. While doing laps and staring at the dirt, hair bands, and Band-Aids at the bottom of the pool I thought about the chemicals, hair bands, and Band-Aids at the bottom of the ocean. This is not what the sea meant when she said, “Come in.” NOAA Fisheries is an integral part of the solution to the problems that face us as a species. Homo sapiens is only one of many species that have a right to thrive—both for our benefit and their own.
“The castle of Cair Paravel on its little hill towered up above them; before them were the sands, with rocks and little pools of salt water, and seaweed, and the smell of the sea and long miles of bluish-green waves breaking for ever and ever on the beach. And oh, the cry of the seagulls! Have you ever heard it? Can you remember?” ― C.S. Lewis, The Lion, the Witch and the Wardrobe
While perusing a glossary of nautical terms in the downtime after a marine mammal watch, I discovered “caravel” a small, highly maneuverable sailing ship used by the Portuguese in the 15th and 16th centuries. The Niña and the Pinta, of 1492 notoriety, were caravels. I wondered whether this term had inspired C. S. Lewis’ naming of Cair Paravel. I will not remember the cry of seagulls so much as I will the cat-like meow of the common murre, at least that’s what they sounded like to me at the time. I’m a compulsive Googler, so that’s how I came upon this Minecraft version of Cair Paravel.
It made me think of my students and how NOAA scientists are the stars of real-world exploration and discovery. Scientists are also world-builders of a sort—reports on their findings influence policy-makers, lawmakers. As science moves forward, it continuously corrects itself as new things are discovered. Listening to the latest science can make or break the world.
And oh, the cry of the scientists! Have you ever heard it? Can you remember?
A Minecraft version of Cair Paravel.
A hatchetfish and a lanternfish reflect on the Teacher at Sea experience.
Mission: Acoustic Trawl Survey (Leg 3 of 3) Geographic Area of Cruise: Pacific Ocean/ Gulf of Alaska Date: Wednesday, August 16, 2023
Weather Data Lat 59.47 N, Lon 144.1 W Sky condition: Cloudy with Rain Wind Speed: 22.62 knots Wind Direction: 125.44° Air Temp: 14 °C
Science and Technology Lab
While on the third leg of our cruise we have had a lot of weather delays, so when the going gets rough the Oscar Dyson science team calibrates! Plus they do not hesitate to work on a couple special projects. No time is wasted. In a secluded bay, waiting for the storm to pass, lots of work can be done to further science.
As I mentioned, this summer has been cold, dark, rainy, and windy. As a fisher person who works in this environment, I cannot overstate how important the internet has become with weather apps like Windy. They accumulate data from oceanic buoys, local weather stations, and satellite images to create a picture like the one you see below.
This image is from the weather app Windy. The white lines indicate the wind direction and the warmer colors are higher wind speeds.
The crew and scientists were able to be proactive in their decision to find a safe place to harbor and then could set up a work plan through the weather day.
Calibration of the Ships Echosounders
The Oscar Dyson’s echo sounders get calibrated about four times a year, at the start and end of the winter and summer field seasons. Because this is the last leg of the cruise, and we are nearing the end of the summer, a weather day is a good day to make sure they are working well
The first step in calibration is to set up down riggers on the starboard, port and aft decks.
From left to right Abigail McCarthy, Robert Levine and Matthew Phillips, part of the night crew, head outside to place the down riggers.
Once placed, the downrigger lines are very cleverly connected underneath the boat, so all three lines meet.
Downrigger mounted on a railing
Where all three lines meet, a single line is suspended directly down underneath the keel of the boat where the echo sounders are located. The down line has a tungsten carbide sphere suspended above a lead weight. The scientists use the known target of the sphere and the known properties of the water column to figure out the difference between expectations and reality in their calibration. The tungsten carbide sphere works extremely well for calibration because it is extremely dense when compared to water, has a known sound reflection, and allows calibration at multiple frequencies.
Pictured above is a screen scientists see as they are moving the sphere around for calibration.
The picture is showing a black circle representing the transducer face as observed from above. The blue dots represent individual measurements of the reflected echo of the calibration sphere as it is moved around in the transducer beam. Using this calibration software the scientists can evaluate the measurement sensitivity and the beam characteristics of the echo sounders.
Calibrating the acoustics was not the only event that happened while weathered deep in a fjord arm of Nuka Bay.
The MiniCam
While waiting out the weather, other members of the science team had a chance to work with a new piece of equipment called a minicam.
The MiniCam, pictured above, has two stereo cameras which can film marine organisms.
The purpose of this camera is to connect the images it records to the backscatter shown with the Oscar Dyson‘s echo sounders. Again, backscatter, as I mentioned in the previous blog, are images that are produced when the echosounders’ different frequencies are reflected back to the ship. The images created by sound are shown on a computer screen and can be used to identify different species of fish or other marine organisms. The images need to be verified by either the minicam or trawl sampling. Scientists want to make sure that the length and species of what they see in the camera can relate to the scaling of the backscatter. The minicam was deployed by scientists and the crew several times to look at the fish and euphausiids in the water column, while we waited out the bad weather.
Getting ready to suspend the MiniCam before it is lifted over the side of the boat from the Hero deck.
Recreational Fish Finders “Little Pingers” Project
This is a project by NOAA oceanographer Robert Levine. The echosounders that are suspended below the Oscar Dyson are extremely precise and expensive. Robert and a colleague want to compare the echosounder’s data/readout for recreational fish finders to the echosounders on the Oscar Dyson. There are situations where scientists would love to monitor fish and marine organisms’ populations, but may not need the accuracy and precision of the scientific Simrad echosounders.
Robert Levine working with the ” Little Pingers.” Environments on board a ship can be challenging to work in, as seen here.
They also might not be able to recover the fish finders, so having them less expensive is very important.
At this point they are just collecting data and monitoring performance with the recreational fish finders, affectionately called “little pingers.” Later in the project they will do more of a data comparison to the Oscar Dyson‘s echo sounders.
Personal Log
On board a ship, one way to keep the crew’s spirits up in bad weather is excellent food. According to the people I have worked with so far on the cruise, the meals on this leg of the acoustic-trawl survey have been amazing.
Meet The Dream Galley Team
From left to right, Rodney Bynum and Angelo Santos
Meet the Dream Galley Team. From left to right, Rodney Bynum and Angelo Santos. These men share a passion for food and see how it brings smiles to the faces of their customers, friends, and family. Both have fathers who worked on ships in the Steward Department. Rodney fondly remembers his father bringing home exotic food from all over the world. His father inspired him to open a Soul Food restaurant in Norfolk, Virginia. Years later, Rodney decided to take his culinary career in a different direction: cooking on a ship. The Oscar Dyson was his first time working on a ship and he has really enjoyed it thus far. The crew loves his congenial personality, mad cooking skills, and awe-inspiring work ethic.
Angelo started cooking at the age of 11, often helping his mom roll lumpia (Filipino egg rolls) and make other traditional Filipino food while religiously watching Giada de Laurentis, Emeril Lagasse, and Ina Garten on Food Network. Angelo grew up in San Francisco and rural Oregon, spent 3 years in San Diego, and is now based in Oregon once again while traveling the world for work. In Oregon, he decided to major in Culinary Arts and graduated with his associate’s degree after going through Linn-Benton Community College’s Culinary program. Angelo mentioned, “culinary school isn’t required, but it helps you gain a fundamental understanding of cooking to prepare you for the real world.” He recommends trying out a restaurant job before spending money on tuition for culinary school.
East Coast meets West Coast aboard the Oscar Dyson. Both men have solid fundamentals in cooking from their years of experience as restaurant chefs. Angelo is the Chief Steward while Rodney is the 2nd Cook. The Chief Steward is in charge of galley operations while the 2nd cook provides breakfast and assists as needed. Chief Steward is like an Executive Chef position on land while 2nd cook is like a breakfast cook/prep cook/dishwasher. Rodney and Angelo often collaborate for menu ideas and feed off each other’s passion for delicious food.
Both of them enjoyed high school and had lots of advice for students looking into a career in Culinary Arts. As I interviewed them, they’d often finish each others’ sentences in agreement.
Rodney: “If you’re looking to become a good chef, don’t be afraid to taste everything, including food that may not be familiar to you. Every job in the kitchen matters, whether it’s the prep cook, dishwasher, or executive chef. Learn every position and never stop learning.”
Angelo attended culinary school shortly after graduating high school, so he found it to be stressful and chaotic, but very rewarding. He mentioned, “Focus as much as possible on having a good work-life balance. Find the joy in simple pleasures, take care of your mental health, and make friends outside of work. Work on networking with peers who share your passion for food as well as people outside of your cohort. Connections can help a lot.” Angelo enjoys cooking on ships because the compensation was very good. The only chef jobs on land that compare to this salary are executive chefs at very high end venues and private/personal chefs. Being able to travel around the world on business was a cool perk of being a chef at sea.
Overall, both men agreed that some of the best moments of pursuing a career in the food industry have been about seeing the joy that good food brings to people. Life is too short to not eat well and this is especially appreciated when one works on a ship. It makes all the difference for the morale of a ship to know that while you’re away from your loved ones, you can still eat well.
Finally, I have to give Angel credit for helping me write the sections about the “Dream Galley Team,” not only is he a great cook but also a fantastic writer.
This beautiful latte was made by Angelo Santos on the Oscar Dyson
Mission: Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS)
Geographic Area of Cruise: Hawaiian archipelago
Date: Tuesday August 8, 2023
Weather Data from the Bridge
Temperature: 27.06° C
Latitude: 29°53’0” N
Longitude; 174°24’0”W
Science and Technology Log with Career Highlights
Previously, I wrote about the day-time operations focused on surveying whales, dolphins, and birds. Through the 25-powered binoculars (big eyes), the large mammals in the distance look microscopic. Now, the sun has set and I take us underwater to learn about the tiny world of ichthyoplankton, magnified to reveal intricate details of their exquisite structures.
Weather permitting, Nich Sucher (Survey Technician) works with the deck crew to deploy the CTD, which measures conductivity, temperature, and depth. This information is used to help scientists understand the physical, chemical, and biological changes of the ocean to help inform them of environmental changes. For example, Nich explained that data from CTDs are used to better understand why tuna were migrating away from Hawaii and towards California. The data can help answer whether the tuna are moving north for access to more oxygen in the water or for cooler temperatures. On our project, we deploy the CTD down to 1000m because that is where some of our deep diving cetacean species feed. Also, the temperature & pressure affects how sound travels through the water. This information can be used to calculate the speed of sound at different depths.
Logan Gary (Able-bodied Seaman) deploys the CTD at sunset. Photo Credit: Gail Tang
Nich wanted to work for NOAA since he was in middle school! In high school he fell in love with fish. Initially he went to college in Iowa for soccer and then transferred to Carthage College, in Kenosha, Wisconsin to study environmental science, conservation and ecology. Nich did an independent study with his aquatic ecology professor on a coral reef project in Roatan, Hondurus. His senior thesis investigated the feasibility of releasing captive-bred axolotl (an adorable salamander that’s critically endangered and possibly extinct in nature) into the wild. After college, he had a job at an aquarium, and while he temped at US Fish and Wildlife studying chub and salmon, NOAA reached out about his job application. He started in January 2022 on the NOAA Ship Oscar Elton Sette!
Nich Sucher (Survey Technician) with recently pressure-shrunken styrofoam head. Photo Credit: Fionna Matheson (Commanding Officer)
Since the CTD is deployed to 1000m, a common extracurricular activity is to attach styrofoam objects to the instrument because they shrink as a result of the pressure! On a previous leg, Commanding Officer Fionna Matheson shrunk a styrofoam head, which can be seen in the picture of Nich above. A few of us shrunk decorated styrofoam cups.
Regular-sized styrofoam cup with Sierpiński’s Triangle DesignPressure-shrunk styrofoam cupRegular and shrunk styrofoam cups for size comparison
Artist of the cup from top to bottom: Jennifer McCullough (Lead Acoustician), Erik Norris (Acoustician), Gail Tang (Teacher at Sea), Alexa Gonzalez (Acoustician). Photo Credit: Gail Tang
The whole process of the CTD deployment and retrieval takes about an hour to an hour and a half. The Isaacs-Kidd Midwater Trawl (IKMT) net tow usually follows. Jessie Perelman and Dre Schmidt are the plankton researchers on board this leg of HICEAS. Most nights, we do 2-3 tows of the net. (They are affectionately called a “tow-yo” because the net gets towed in and out several times.) They use an inclinometer, a.k.a. angled angle, to measure the angle of the line (see picture below) and then confer with a chart to determine the length of the line needed to reach the desired depth. The chart is a good way to avoid on-the-spot trigonometric calculations. But it’s a good exercise to ask yourself anyway: if you know the desired depth and the angle, how would you calculate the length of the line needed?
Dre Schmidt measuring with the angled angle. Photo Credit: Gail Tang
After the tows, we bring the larvae into the wet lab and the fun begins. The goal is to sort out the fish larvae from the other larvae. Truthfully, I am not very good at sorting the fish and I just like to look at the organisms under the microscope. The most awe-inspiring creatures I saw under the scope were the shelled pteropods (sea butterflies) and a juvenile sea star that, according to Dre, may have recently morphed from the larval stage. With the naked eye, they look like marks made with a sharp pencil, but under the scope, the enormity of their existence is profoundly moving. While I could not capture these beauties in a photograph, I was able to capture other creatures.
Phromina living inside a salp. Photo Credit: Gail TangPolychaete and squid. Photo Credit: Gail Tang
Squid
Personal/Food Log with Career Highlights
As I fall into a daily routine, I periodically need small bits of irregularity for stimulation. This week, I was privileged enough to work with Chef Chris. Chef Chris is originally from north Philadelphia. In the absence of cable during childhood, he watched cooking shows like Yan Can Cook, Frugal Gourmet, and Julia Child on PBS. He started off cooking on NOAA Ship Rainier and now is the Chief Steward on NOAA Ship Oscar Elton Sette. We collaborated to make some pork dumplings and vegetable spring rolls for everyone. I cook at home often, but not for so many people, so Chris was essential in helping me scale up the dishes. We bonded over not measuring out ingredients so here is approximately the two recipes we used.
Chief Steward Christopher Williams cooking the eggroll fillings. Photo Credit: Gail Tang
Pork Dumpling Filling
5 lbs of ground pork (when my mom makes these, we use a mix of lean ground pork and fatty ground pork)
Mirin (I use Shaioxing wine, but mirin is a good substitute!)
Soy sauce (we used Kikkoman; I like to use Pearl River Bridge Light Soy)
Green onions
Sugar
The most gorgeous dumplingsThe most satisfying dumplings
Several of us worked together to help fold the dumplings and egg rolls. I delighted in the number of different hands that contributed to feeding our community. Chef Chris expertly cooked everything and it was all gobbled up!
Chef Chris Williams and Gail TangJessie Perelman, Matt Benes, Gail Tang, Dre Schmidt wrapping dumplingsGail Tang, Octavio De Mena, Jamie Delgado, Jessie Perelman rolling eggrolls
At night, I assist Jessie Perelman and Dre Schimdt with their plankton research. They were the first to come by to help fold dumplings. Jessie did her undergraduate work in biological science at University of Southern California (USC) with a plan to go to veterinary school. She worked in a marine science lab at USC, and then studied abroad in Australia to take more marine biology classes not available at USC. After she graduated, she got a job as research assistant at Wood’s Hole Oceanographic Institution, where she solidified her passion for research. She applied for graduate school and ended up at the University of Hawaii studying biological oceanography. Her dissertation focused on oceanographic influences on mesopelagic communities across eastern Pacific Ocean using insights from active acoustics, nets, and other sampling techniques. An interesting interdisciplinary part of her background includes learning about international policy on issues like deep sea mining. The international meetings with delegates were very informative for her. She’s also worked on science communication writing, such as science blogging. In Fall 2022, Jessie started as a Marine Ecosystem Research Analyst at NOAA!
Dre Schmidt received her bachelors in biology at Florida State University. She took Calculus, Mathematical Modeling for Biology, Analysis and Statistical Design, and Physics to supplement her biology degree. She volunteered at a research lab on campus and after college, took a couple of years off to work in marine science education for 5th grade to college level students. She went for her master’s degree in Kiel, Germany to study physiological effects of low-level warming on coral and their larvae. She has been at NOAA for 2 years, first as a research associate and now as an essential fish habitat coordinator. What she loves about her job is the variety of responsibilities. She keeps busy by sorting plankton, doing genetics lab work, analyzing data in R, writing up results, and going to sea! Engaging in these different tasks help to activate different parts of the brain, which I can totally relate to! Her advice to students is to know your worth and ask for what you deserve. Her favorite fish larva is the very ugly Centrobranchus andreae simply because her name is found within the name of the organism. I can’t blame her because my favorite flower is the Gaillardia for the same reason.
Andrea with Andrea
Matt Benes (Able-bodied Seaman and Deck Boss) took a break in his duties to fold some dumplings with us. Though Matt declined to be interviewed, I can tell you we share a deep appreciation for food as a mechanism for cultural, historical, and political understanding.
Jamie Delgado (Medical Officer) joined in on the egg roll wrapping. Jamie received her bachelor’s in science and nursing at Rutgers University. She joined the Public Health Service (PHS), and worked at the Indian Health Service (IHS) in northern Arizona. Later, she worked at the National Institutes of Health (NIH) as a research nurse specialist. Jamie earned her Doctor of Nursing at University of Maryland before coming to NOAA as ship medical officer. Jamie has so much good financial advice about scholarships and loan repayments programs. Check out these links to learn more:
She also shared that you can retire in a total of 20 years with uniformed services, you get a pension, healthcare benefits, a housing allowance, a food allowance, 30 days paid leave, and unlimited sick leave. Jamie has been in service for 10 years, and with NOAA for 1 year and 5 months.
Jamie also helped me out during our in-port during Leg 1. Snorkeling had dislodged some ear wax and clogged my ear for a couple of days making daily life really uncomfortable. Jason Dlugos’s (3rd Assistant Engineer) “ear beer” helped, but I was still off balance. Jamie had to endure the task of flushing my ear out over the course of two days. Eventually, I did have to go to urgent care to get the rest out. Now I’m 100%!
Last but never least, Octavio De Mena, a.k.a OC, (General Vessel Assistant in the Deck Department) came by to roll some egg rolls. He is originally from the Republic of Panama and loves classic rock music. While we have no intersection in our movie tastes, we share some similarities in the food we ate growing up due to the large Chinese population in Panama. According to the Harvard Review of Latin America, the first Chinese immigrants arrived in Panama in 1854 to build the Trans-Isthmian Railroad. The inhumane treatment and disregard for the workers’ welfare is reminiscent of the situation a decade later with the Transcontinental Railway in the United States. This convergence of cultures led to haw flakes and dried plums in both our childhoods!
OC was an aircraft mechanic in the military reserves, and a security contractor in Latin America. He decided to come back to the U.S. to fulfill his dream job as a professional mariner. On his journey in pursuing his dream, he volunteered for the civil air patrol, and served as an auxiliary for search and rescue flying small Cessnas. He saw a NOAA ship at this job which prompted a search for a position within NOAA. He has been on the NOAA Ship Oscar Elton Sette since February 2023. On the ship, OC and I are regulars in the forward mess. Sometimes having opposite tastes works out in your f(l)avor, as I get to eat OC’s tomatoes and watermelon jolly ranchers.
Mission: Acoustic Trawl Survey (Leg 3 of 3) Geographic Area of Cruise: Pacific Ocean/ Gulf of Alaska Date: Sunday, August 13, 2023
Weather Data Lat 59.12 N, Lon 150.11 W Sky condition: Partly Cloudy Wind Speed: 13 knots Wind Direction: 330° Air Temp: 14 °C
Science and Technology blog
The ocean is a really big place. We have really only mapped about 5% of the ocean bottom. How do we manage fisheries if we have to count fish in an area that is overwhelmingly large? This is where the genius of acoustics and trawl sampling complement each other. The scientists aboardNOAA Ship Oscar Dyson use the echo sounders to find fish or other animals lurking in the ocean and then they can extrapolate and upscale that data to a much larger area which is covered by their transects.
Wait! That is a lot of information using language that folks don’t really use at the dinner table. Could you please explain this in more basic terms? You bet, as a matter of fact in the last couple of days I have been swimming in a sea of new vocabulary, talking to really smart people and trying to keep up with the conversation that it almost makes my head explode. Don’t worry, I am safe. But it’s really impressive how scientists have developed ways to accurately know fish and marine organism populations in the ocean with out having to sample all of it.
Acoustics
Acoustics uses the echo-sounders a lot like a fish finder, but the ones on NOAA Ship Oscar Dyson are much more capable than the type you would find on your boat. The echo-sounders are attached to the bottom of a lowered centerboard—essentially a large keel—in the center of the boat, and they measure five different frequencies with different wavelengths.
View of the 5 different frequencies measured by the echosounders, one in each frame. The darker marks on the screen could be fish, jellyfish, krill or other marine organisms, this is referred to as “backscatter.” The red circles show the different frequencies used to measure the backscatter.
So, if we can see the fish using acoustics, why do scientists need to sample using a trawl net? As you can see above, the marks in the backscatter can show the depth and the approximate shape of objects, but there is not enough detail to tell exactly what kind of organism is present. Most of the scientists on board have a pretty good idea what kind of fish or organisms are present, but the most definitive way to know is to take a trawl sample.
Trawl Sampling
The trawl net as seen in the picture below is being set off the aft deck.
The part that is in the air is called the codend. That is the section of the net where the specimens are ultimately collected.
The trawl is a about 172 meters long and it stored on these rollers on the back deck.
When the trawl is deployed to the depth that the scientists want to sample, the net will funnel fish and other organisms into it. This is called flying the net.
The screen above diagrams three different views of the net as it is pulled through the water. You can see that the trawl net was not directly behind the boat and went to a depth of 21.5 m.
In this image you can see the net and how far back it trails behind the Oscar Dyson.
I just have to include one more view of the trawl net from the bridge as it is pulled behind the boat.
This image was taken when the crew was bringing the net back into the boat, so the depth is shallower.
The next image shows the path that the net was pulled through the water.
The acoustics show the backscatter which the scientists make the trawl target. The next step is to process what is captured in the codend of the trawl and see exactly what is present.
Because the trawl is dragged through the water, it catches different organisms at different times. The scientists want to know when the different organisms were caught so they have cleverly attached a camera to the side of the net. Through the camera they can see which type of fish came into the trawl. Ultimately, this links the kind of acoustic backscatter viewed in the echograms recorded during the trawl to exactly the type of organism caught by the trawl.
The camtrawl: a camera that records the type of fish entering the net and when they enter.
Below is a picture of some fish as they enter the trawl net and move towards the codend.
The camera is looking across the net as the fish move past. The fish in the picture are pollock, the type of fish we are looking for on this leg of the cruise.
Transect Lines
So how do scientists take this information and extrapolate the data to a broader area? While the Oscar Dyson is out at sea they run transect lines while recording acoustic data. Transect lines are specific paths in the ocean. The picture below shows the transect lines that we plan to do and have done on this leg of the cruise.
The red lines are the transects we have done and the blue lines are the transects scientists plan to do in the remainder of this leg of the cruise. If you look closely there are pictures of fish symbols on the transect lines where the ship has made trawl samples.
Using the acoustic data that the echo-sounders provide and verifying the types of fish and other marine organisms through the trawl sampling allows the scientists to predict, with a high level of certainty, the amount and types of marine organisms that are present along the transect lines that were not trawl-sampled. Thus saving the taxpayers money, and allowing fisheries managers to use good data, keeping the fishery viable, and allowing commercial fishing boats to have reasonable catch limits.
Scientist in the Spotlight
Honestly it takes a team to make all of this happen. But, half of our team is sleeping at the moment, I have the night shift from 4pm to 4am, so I am going to introduce one fabulous expert in acoustics and fisheries:
Abigail McCarthy in the Acoustics Lab
Abigail McCarthy has been working for MACE: Midwater Assessment and Conservation Engineering Program since 2007. She received her undergraduate degree in Biology from Wellesley College and then obtained a Masters in Fisheries from Oregon State University.
For fun, she surfs and enjoys long-distance prone paddle board races. She has recently found a new love with fly fishing.
Aboard the Ship Oscar Dyson, she is working as a specialist helping to run the acoustics lab.
I asked Abigail what she thought of about her educational experience? She immediately said, “I love learning! High school and college were both a lot of fun.”
What would be a good suggestion for a young aspiring high school student pursuing a degree related to ocean studies or science in general?
Her response was great: “Being curious and working hard is more important than being brilliant. Persistence and determination will get you where you want to be in the future.” Finally, “Learn to code! Become familiar with programing languages like Python and R.”
Hopefully, I answered your burning questions about the use of acoustic trawl sampling, and surveys. Yet, there is so much more to learn. Why not take a trip yourself? Check NOAA’s website out and just apply.
