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Jenny Gapp: Let Them Eat Hake! August 14, 2023

NOAA Teacher at Sea

Jenny Gapp (she/her)

Aboard NOAA Ship Bell M. Shimada

July 23 – August 5, 2023 

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 .

a graphical representation of the spectrum of soundwaves. from left to right, a red line meanders up and down at increasing frequencies (2 Hz, 20 Hz, 200 Hz, 2 kHz, 20 kHz, 200 kHz, 2 MHz) and decreasing wavelengths (170 m, 17 m, 1.7 m, 17 cm, 17 mm, 1.7 mm, 172 um.) The labeled wavelengths are compared to images about the same size: a baseball field (170 m), a tractor trailer (17 m), two people holding hands (1.7 m), a sub sandwich (17 cm), a penny (17 mm), the width of a quarter (1.7 mm), and grains of salt (172 um). Ranges of frequencies are labeled "infrasound" (2 Hz to 20 Hz), "audible sound" (20 Hz to 20 kHz), and "ultrasound" (20 kHz to 2 MHz).
Spectrum of soundwaves illustration from BYU Acoustics Research Group

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.

Jenny, wearing overalls, rubber boots, rubber gloves, kneels on one knee to scrub an overturned plastic basket on the aft deck. there is a bucket of cleaning solution to her right and a stack of three more baskets to her left.
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 stands at metal box, with indicator lights and switches, mounted on a wall. She holds a corded phone receiver up to her ear with her left hand. With her right hand she reaches toward a button or dial on the control panel.
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.

close up view of a metal panel - a red circle, surrounded by a yellow ring, on a red background. over the center of the circle, there's a beige-colored smear of what must be tiny barnacles.
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, wearing a blue NOAA Corps uniform, stands at a white metal post (housing what must be the gyro repeater) near a railing aboard NOAA Ship Bell M Shimada. He holds his right hand up, pointing out over the bright blue ocean, and looks in the direction he points.
CO Slater at one of Shimada’s gyro repeaters.
CO Slater, wearing a blue NOAA Corps uniform, sits in his Captain's Chair on the bridge. Facing away from us, he holds his binoculars up to his eyes to scan the horizon.
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. 

an illustration of the surface of the ocean, if it were contained in a square angled toward the viewer. an orange arrow entering the square from the left is labeled Wind; a blue arrow exiting the square to the right is labeled "direction of wind advance." near the arrow, small curved white lines indicate small waves emanating out in all directions, but in the direction of the arrow there are many more; farther to the right, they spread out some; all the way to the right, they are large waves. This progression is labeled "ripples to chop to wind waves," then "full developed seas," then "changing to swell." An oval with a point at the back describes the center of the image, where most of the waves are, and a nearby measurement bar marks the length of that shape as the length of fetch.
An illustration of fetch. Image origin.

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. 

NOAA Fishwatch logo, reading: FishWatch U.S. Seafood Facts, NOAA, www.FishWatch.gov


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!

photograph of a hake, cutout and superimposed on a stylized background. text reads: Wild Pacific Hake (Whiting). A North Pacific Speciality. Wild Pacific Hake (Whiting) is unique to the waters off the coast of Oregon and Washington. But chefs worldwide like this sustainable fish for its rich, white flesh, flaky texture, and mild and slightly sweet flavor. Calories: 90 per serving. Protein: 18.31 g per serving. Fat: 1.31 g per serving. Omega-3: 260 mg per serving.
Image of a hake with nutritional information from American Seafoods.
Is Pacific Whiting Sustainable? U.S. wild-caught Pacific whiting is a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations. Environmental Impact Icon Availability Frozen whiting is available year-round. Feeds Icon Source U.S. wild-caught from Washington, Oregon, and California. Farming Methods Icon Taste Mild and slightly sweet. Human Health Icon Texture Soft and less flaky than other whitefish such as cod and pollock.  Human Health Icon Color Raw and cooked whiting ranges from pure white to off-white. Human Health Icon Health Benefits Whiting is a good source of selenium, vitamin B, magnesium, and protein. Nutrition Facts Servings: 1; Serving Weight: 100 g (raw); Calories: 90; Protein: 18.31 g; Total Fat: 1.31 g; Total Saturated Fatty Acids: 0.247 g; Carbohydrate: 0 g; Total Sugars: 0 g; Total Dietary Fiber: 0 g; Cholesterol: 67 mg; Selenium: 32.1 mcg; Sodium: 72 mg
A screenshot from NOAA’s sustainable seafood profile on Pacific whiting (hake).
image of plated Garlic Baked Whiting on a bed of rice, garnished with lemon and parsley. Garlic Baked Whiting Ingredients 4 whiting fillets Kosher salt Freshly ground black pepper 5 Tbsp butter, melted 2 cloves garlic, minced ¼ tsp red pepper flakes Juice and zest from 1/2 a lemon 1 lemon, sliced into rounds Parsley for garnish Directions Preheat oven to 400°. Season whiting with salt and pepper and place on a small baking sheet. Mix together butter, garlic, red pepper flakes, lemon juice, and zest then pour over whiting fillets. Place lemon rounds on top and around fillets. Bake whiting for 10-12 minutes or until fish is fork tender.
Hake recipe courtesy of Pacific Seafood.
Click to enlarge.
image of plated spicy baked whiting with sides of couscous and asparagus Spicy Baked Whiting Ingredients 4 Pacific whiting fillets 2 Tbsp olive oil Rub ingredients: 1 tsp garlic powder 1 tsp dried parsley 1 tsp onion powder 1 tsp red pepper flakes 1 tsp of lime juice 2 tsp of seasoned salt Directions Preheat oven to 400°F. Mix all rub ingredients together. In a baking pan, coat fish with olive oil. Then coat the fish in the spice mixture. Place the fish the oven and bake for 10-15 minutes until fish is flaky.
Hake recipe courtesy of Pacific Seafood.
Click to enlarge.


Personal Log

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.

view over the aft deck (probably from the flying deck) of NOAA Ship Bell M. Shimada back at Yaquina Bay, and the Yaquina Bay Bridge. In this photo, the sky is bright blue and clear, and the water is calm and bright blue as well.
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 American article 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.

sparkles of bioluminescence on the ocean surface in the daytime
setting sun, about halfway under the horizon, dark blue waves
puffy white clouds against blue sky, above blue water
last light at sunset, just visible under dramatic gray clouds; gray waves reflect just the edges of the yellow light
mostly-set sun creating a line of orange in between dramatic gray clouds and glassy gray seas
view down at blue ocean water
gray seas, blue sky, sun; might be foggy or blurry
turquoise-blue water; blue sky, line of mountainous coastline in the far distance
glassy seas reflect blue and white sky
fog; g


“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? 

screenshot from a video game showing a castle near the ocean
A Minecraft version of Cair Paravel.
photo of a hatchetfish and a lanternfish on a metal table, facing one another. Jenny has added speech bubbles so that the hatchetfish says: "So, what did you think of the Teacher at Sea experience on the Shimada?" and the lanternfish replies: "It was illuminating - and that's not just my photophores talking!"
A hatchetfish and a lanternfish reflect on the Teacher at Sea experience.
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Michelle Greene: Acoustics Team…Do You Hear What I Hear?

NOAA Teacher at Sea

Michelle Greene

Aboard NOAA Ship Gordon Gunter

July 19 – August 3, 2018

 

Mission: Cetacean Survey

Geographic Area: Northeast U.S. Atlantic Coast

Date: July 24-25, 2018

 

Latitude: 40° 2.629″ N

Longitude: 67° 58.954″ W

Sea Surface Temperature: 23.3° C (73.9° F)

Sailing Speed: 1.80 knots

 

Science and Technology Blog:

Today I had the opportunity to shadow the acoustics team in the dry lab.  The acoustics team uses a linear array or a prototype tetrahedral array of hydrophones to listen to the sounds that whales and dolphins make under the water.  So far in this journey, the team has only used the linear array.  The array has been towing behind the ship with the “line” of hydrophones parallel to the surface of the water about 10 meters below the surface.

Linear array of hydrophones
Linear array of hydrophones

The hydrophone is the black device in the cable
The hydrophone is the black device in the cable

When the array is deployed, the acoustics team uses a computer software called PAMGuard to record the sounds and track the clicks and whistles of whales and dolphins.  PAMGuard can be programmed to record sounds in any frequency range.  On this cruise, acoustics is looking at sounds up to about 100,000 hertz.  A human being can hear from about 20 Hz to about 20 kilohertz with normal human speech frequency between 1,000 Hz and 5,000 Hz.  The optimal hearing age for a person is approximately 20 years of age and declines after that.

Beaked whales click at a frequency too high for human hearing; however, PAMGuard can detect the clicks to help the acousticians possibly locate an animal.  PAMGuard produces a real-time, time series graph of the location of all sounds picked up on the array.  A series of dots is located on a continual graph with the x-axis being time and the y-axis being bearing from the ship. The array picks up all sounds, and PAMGuard gives a bearing of the sound with a bearing of 0° being in front of the ship and a bearing of 180° being behind the ship.  The ship creates noise that is picked up by all the hydrophones at the same time, so it looks like a lot of noise at 90°.  The acousticians must sift through the noise to try to find click trains.  Rain and heavy waves also create a lot noise for the hydrophone array.  The acoustician can click on an individual dot which represents a sound, and then she can see a Wigner plot of the sound which is a high resolution spectrogram image of the sound.

A screenshot of a spectrogram from PAMGuard
A screenshot of a spectrogram from PAMGuard

Scientists have determined what the Wigner plot image of a beaked whale sound should look like.

Wigner plot of a True's beaked whale (Mesoplodon mirus) or a Gervais' beaked whale (Mesoplodon europaeus)
Wigner plot of a True’s beaked whale (Mesoplodon mirus) or a Gervais’ beaked whale (Mesoplodon europaeus)

 

Wigner plot of a Cuvier's beaked whale (Ziphius cavirostris)
Wigner plot of a Cuvier’s beaked whale (Ziphius cavirostris)

When a Wigner plot image looks to be a possible Mesoplodon, the acoustician starts tracking a click train on the time series graph in hopes of getting the sound again.  If the acoustic signal repeats, the acoustician then adds it to the click train.  Each time the acoustician adds to a click train, the bearing to the new click is plotted on a graph.  The array cannot calculate the actual location of an animal, so a beam of probability is plotted on a chart.  Then the acoustician uses the angle of each click in a click train to determine a possible location on the port or starboard side of the ship.  If the click train produces a sound that can be localized with the convergence of beams to a certain point, the acoustician can call the visual team to look on a particular side of the ship or ask the bridge to slow down or turn in a certain direction.  Mesoplodons have average dive times of between 15 and 20 minutes and foraging dive times of up to 45 minutes, so there is a time delay between getting the clicks and seeing an animal.

PAMGuard map of a sighting of a beaked whale
PAMGuard map of a sighting of a beaked whale

The objective of this cruise is to find the occurrence of beaked whales, but PAMGuard does not record just beaked whale clicks, so several other whales and dolphins are heard by the array.  Sperm whales (Physeter macrocephalus) have clicks that can be heard by the human ear with an average frequency of 10 KHz.  Sperm whales have a synchronized click train.  It can be thought of as “click click click click…” with about 0.5 to 1.0 second between each click.  Scientists believe the clicks are used for echolocation.  Since it is very dark in the ocean and light does not travel far underwater, sperm whales use their clicks as sort of flashlight for locating food which usually consists of squid.  When a sperm whale senses the location of food, it produces a rapid series of clicks called a buzz.  After the buzz, the animal makes a dive.  If the dive is not successful, in other words the whale did not get food, then clicks return to their normal pattern until another attempt is made.  Clicks are also used for social interaction between sperm whales.  Sperm whales have been very vocal on the cruise so far.

Personal Log

I have been spending my days rotating between the visual sighting team and the acoustics team.  Even when I am not scheduled to be there, I am in acoustics.  I find listening to the sounds very interesting.  I had no idea whales made clicking sounds.  I knew dolphins whistled, but clicking is not a term I was familiar with until this cruise.  We have had several episodes where many dolphins will go by the ship.  When that happens, the whole plot in PAMGuard almost turns black from all of the dots on the screen.  It is amazing to hear all of the clicks and whistles from the dolphins.  My favorite whales right now are sperm whales.  I can now look at the screen and see the clicks and know it is a sperm whale.  I get so excited.

Getting a Mesoplodon click train is like watching a whale lover’s version of Storm Chasers.  When a possible Mesoplodon click train is detected, everybody gets excited in hopes of seeing a beaked whale.  I can really understand how the visual sighting team relies on the acoustics team to find a location.  We have two people on big eyes and two people on binoculars, and the ocean is all around us.  We have a high probability of missing a Mesoplodon, so having the acoustics team getting a click train with convergence in a certain direction helps to focus the visual sighting team in sighting an animal.  The reverse idea is also true.  When the visual sighting team sees a Mesoplodon, they call down to acoustics to see if a click train can be detected.

Life aboard the Gordon Gunter has been a real classroom for me.  I think I learn something new about every five seconds.  Since I have been out of college, I have not dealt with biological sciences much, so this math teacher is relearning some key information about marine animals.  I have really enjoyed seeing the passion in everyone’s eyes for the beaked whales.  When we get a sighting of a beaked whale on the flybridge, everyone rushes to that side of the ship in hopes of just getting a glance at the elusive creature.  When we get a Mesoplodon click train, the acousticians get really excited.  One evening, we got a sustained click train for a Sowerby’s beaked whale (Mesoplodon bidens).  One of the acousticians was not in the dry lab, so I went to try and find her with no luck.  She was really upset when she returned, because she had not been there to see it.  I hope to develop that kind of passion in my students, so they can become great thinkers about life in their futures.

Did You Know?

  1. Even though Moby Dick was a fictional sperm whale, real life event inspired Herman Melville to write the novel.  Check out this page on those events:  https://oceanservice.noaa.gov/facts/mobydick.html.
  2. Sperm whales use an organ in the front of their head, something called the spermaceti organ, to make their clicking sounds.  Check out this PBS article: http://www.pbs.org/odyssey/odyssey/20010809_log_transcript.html.

Animals Seen

  1. Sperm whales (Physeter macrocephalus)
  2. Fin whales (Balaenoptera physalus)
  3. Cuvier’s beaked whale (Ziphius cavirostris)
  4. Risso’s dolphins (Grampus griseus)
  5. Manta ray (Manta birostris)
  6. Whale shark (Rhincodon typus)

Vocabulary

  1. (Ocean) Acoustics – the study of how sound is used to locate whales and dolphins and how whales and dolphins communicate
  2. Bridge – the room from which the boat can be commanded
  3. Click train – a series of whale clicks
  4. Dry lab – a lab that primarily uses electronic equipment such as computers
  5. Echolocation – a process used by whales and dolphins to locate objects.  A whale will emit a pulse, and the pulse then bounces off an object going back to the whale.  The whale can then determine if the object is food or something else.
  6. Flybridge – an open platform above the bridge of a ship which provides views of the fore, aft, and sides of a ship
  7. Hertz – a measure of sound frequency.  For example, when you hear someone singing in a low (or bass) voice, the frequency of the sound is low.  When someone is singing in a high (or soprano) voice, the frequency of the sound is higher.
  8. Hydrophone – a microphone that detects sound waves under water
  9. Spectrogram – a visual representation of a sound
  10. Wigner plot – a high resolution spectrogram
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Michelle Greene: Visual Sighting Team, July 23, 2018

NOAA Teacher at Sea

Michelle Greene

Aboard NOAA Ship Gordon Gunter

July 19 – August 3, 2018

 

Mission: Cetacean Survey

Geographic Area: Northeast U.S. Atlantic Coast

Date: July 22-23, 2018

Latitude: 40° 35.213″ N

Longitude: 66° 6.692″ W

Sea Surface Temperature: 23.4° C (74.1° F)

Knots: 7.85 knots

Science and Technology Blog:

The visual sighting team started early this morning at 6:00 am and had rotating shifts of 30 minutes each until 7:00 pm.  The different shifts included watching with regular binoculars on the port and starboard sides, watching with the big eyes on the port and starboard sides, and being the data recorder for sightings.  I had the opportunity to shadow scientists in each of these positions throughout the first day and actually performed the duties on the second day.

Members of the Cetacean Survey Visual Team on Lookout
Members of the Cetacean Survey Visual Team on Lookout

One of the important jobs the data recorder has is to input the environmental conditions at a certain point in time.  The first measurement to input is the percent of cloud cover which is just a number from 0 to 100. Then the glare magnitude is determined on an ordinal scale from 0 to 4 with a value of zero meaning none and a value of four meaning severe.  After determining the glare magnitude, the percent of glare cover is determined.  Since the two sets of big eyes cover from 90 degrees left of the bow to 90 degrees right of the bow, the glare covering this spaced is what is determined.  The data recorder also has to determine the degree angle and height of the ocean swell.  Swell is not the wind waves generated by local weather.  It is the wind waves that are generated by distant weather systems.  Then the Beaufort scale is used to determine the amount of wind on the ocean.  The scale was developed by Sir Francis Beaufort of the United Kingdom Royal Navy in 1805.  The scale ranges from 0-12.  A zero score means the surface is smooth and mirror like, while a score of 12 means there are hurricane force winds.  Rain or fog is also determined by the data recorder.  Finally, the data recorder has to determine a subjective condition of the weather overall.  This is on an ordinal scale from 1 to 4 with 1 being poor and 4 being excellent.

When a marine animal is sighted by one of the observers, the data recorder has to input several measurements about the event.  The bearing of the location of the animal has to be determined using the big eyes.  Also, the big eyes have a scale in the lens called reticles that determines distance from the ship to the animal.  A conversion scale can then be used to determine how far away the animal is in meters or nautical miles.  The number of animals sighted, including any calves that are in the group, has to be given.  The group’s swim direction has to be determined based on bearing from the ship.  If possible, the species of the group has to be given.  Since the objective of this survey is to find the occurrence of Mesoplodons in the North Atlantic Ocean, determining the species is very important.  Also the observer has to give the initial cue as to what determined the identification of the species.  Several different cues are available such as the body of the animal, the blow of a whale or dolphin, or the splash.

The software used to input the occurrence of a marine mammal automatically inputs the GPS of a sighting.  The initial route for this survey is a zig zag pattern out of Rhode Island towards Georges Bank.  There are several canyons with very deep waters (over 1,000 meters) which is where the Mesoplodons make foraging dives to get food.  Instead of making a straight line through the canyons and only making one pass through the area, using zig zag routes gives the survey a better chance of locating Mesoplodons.  The chief scientist uses the information from sightings to track a path for the ship to take the next day.  Sometimes the acoustics team hears possible Mesoplodons.  If the acoustics team can find a convergence of the area of an animal, they will tell the ship to go at a slower rate or turn.

The map here shows the sightings of Mesoplodons from the beginning of our journey and the zig zag pattern taken by the chief scientist.  The first day of our journey, a storm was coming up the East Coast.  The Gordon Gunter‘s Commanding Officer (CO) determined that we could run from the storm by going east in a straight line direction instead of doing the zig zag motion.  The CO was correct, because we did not have bad weather.  The ocean had a lot of high swells which made the boat rock tremendously at times but no rain.

GU18-03_Map_24July2018_wLegend
A map of the daily route of the Gordon Gunter based on sightings.

 

Personal Log

I have found my favorite place to be on the visual sighting team…being the data recorder.  Statistics is my passion, and being the data recorder puts me in the middle of the action getting mass amounts of data.  It also helps that the data recorder sits in a high chair and can see a wide area of the ocean.  The scientists have been very helpful in finding me a milk crate, because that chair is so high I cannot get onto it without the milk crate.  Being the data recorder can be intense sometimes, because multiple sightings can be made at the same time.  In any free time I have, I will fill in as the data recorder.  It is lots of fun!

Data Recorder
Favorite place to be on the visual team – Data Recorder

One thing that was a little intimidating to me at first was the intercom system.  I would hear things like, “Fly Bridge Bridge.”  Then the data recorder would say “Bridge Fly Bridge.”  I had no clue of what they were talking about.  Then all of a sudden it made sense to me.  In “Fly Bridge Bridge,” someone from the Bridge is calling up to us on the Fly Bridge.  The Bridge has a question or wants to tell the people on the Fly Bridge something.  Since I figured it out, I am ready to go.

I have learned so much on this cruise in the short time I have been aboard the Gordon Gunter.  My head is exploding with the numbers of lessons that I can incorporate into my statistics classes.  I have also talked with the acousticians, Jenny, Joy, Emily, and Anna Maria, and have come up with lessons that I can use with my algebra and calculus classes as well.  The scientists have been very generous in sharing their knowledge with a science newbie.  Being a math teacher, I want to be able to expose my students to all kinds of content that do not deal with just the boring math class.  Being a Teacher at Sea has opened up a whole new experience for me and my students.

We have an interesting participant in our cruise that I was not expecting but was happy to meet…a seabird observer.  Before this cruise I did not know there were birds that pretty much lived on the surface of the ocean.  These birds have been flying around the ship which is about 100 nautical miles from shore.  The seabird observer documents all sightings of seabirds and takes pictures to include in his documentation.

Did You Know?

Reticles are the way a pair of binoculars helps observers to determine the distance to an animal; however, the conversion from reticles to distance is not an instantaneous solution.  Based on the height of a pair of binoculars on the ship, reticles can mean different distances.  A conversion chart must be used to determine actual distance.

Check out this article on how to estimate distance to an object with reticles in a pair of binoculars:

Using reticle binoculars to estimate range

Animals Seen

  1. Sperm whales (Physeter macrocephalus)
  2. Fin whales (Balaenoptera physalus)
  3. Cuvier’s beaked whale (Ziphius cavirostris)
  4. Risso’s dolphins (Grampus griseus)
  5. Bottlenose dolphins (Tursiops truncatus)
  6. Common dolphin (Delphinus delphis)
  7. Great shearwater bird (Puffinus gravis)
  8. Cory’s shearwater bird (Calonectris borealis)
  9. Wilson’s storm petrel bird (Oceanites oceanicus)
  10. Leach’s storm petrel bird (Oceanodroma leucorhoa)
  11. White-faced storm petrel bird (Pelagodroma marina)
  12. Red-billed tropicbird (Phaethon aethereus)

Vocabulary

  1. acoustician – someone whose work deals with the properties of sound
  2. bearing – the direction from your location to an object in the distance starting at 0° which is located at absolute north.  For example, if an animal is spotted at 90°, then it is due east of your location.
  3. blow of a whale – the exhalation of the breath of a whale that usually looks like a spray of water and is an identifying feature of different species of whales
  4. bow of a ship – the point of the ship that is most forward as the ship is sailing (also known as the front of the ship)
  5. cloud cover – the portion of the sky that is covered with clouds
  6. foraging dive – a type of deep dive where a whale searches for food on the ocean floor
  7. glare – the light reflected from the sun off of the ocean
  8. nautical mile – a measurement for determining distance on the ocean which is approximately 2025 yards (or 1.15 miles) or 1852 meters
  9. port side of a ship – when looking forward toward the bow of the ship, the left side of the ship is port
  10. starboard side of a ship – when looking forward toward the bow of the ship, the right side is starboard
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Michelle Greene: Setting Sail on the Gordon Gunter, July 20, 2018

NOAA Teacher at Sea

Michelle Greene

Aboard NOAA Ship Gordon Gunter

July 20-August 3, 2018

Mission: Cetacean Survey

Geographic Area of Cruise: Northeast U.S. Atlantic Coast

Date: July 20, 2018

Weather Data from the Bridge

Latitude: 41° 31.838′ N

Longitude: 71° 19.018′ W

Air Temperature:  26.7° C (80° F)

Conditions: Sunny

Science and Technology Log

Beaked whales are elusive creatures that roam all of the world’s oceans.  The purpose of this cetacean cruise is to find the occurrence and distribution of beaked whales in the northeast Atlantic off the coast of Rhode Island and Massachusetts.  The beaked whale is a toothed whale from the family Ziphiidae.  Several types of beaked whales have been spotted in this region including the True’s beaked whale (Mesoplodon mirus) and the Cuvier’s beaked whale (Ziphius cavirostris).

To find the occurrence of beaked whales, the scientists are using several different methods.  The first method is a visual sighting of the animals.  High-powered binoculars, affectionately termed “big eyes” can see animals from several nautical miles away.  Then regular binoculars are used to scan the areas closer to the ship.  The second method scientists are using is by passive acoustics.  Acousticians are using two different types of listening devices to try to hear the whales.  The first device is called a linear array.  In this device, four hydrophones are attached to a tube in a linear pattern.  The array is then towed in the water behind the ship, and acousticians can hear the whales when they communicate.  The acousticians can then determine how far the whale(s) is(are) from the device.  However, with this type of array, it is difficult to calculate how deep the whale is in the water.

In an effort to improve detection of the depth of a beaked whale, a new array has been designed.  This tetrahedral array is designed so that the four hydrophones are placed in a way that is not linear two-dimensional space but in a more three dimensional space, so scientists can detect not only the distance of a whale but the depth.  We will be testing a new prototype of this array during this cruise.

Personal Log

Arriving the day before the Gordon Gunter sailed allowed me to see some pretty interesting things.  I got to help two of the scientists put up the “big eyes.”  These binoculars are really heavy but can see very far away.  On the day we sailed, we were able to zero the binoculars which means we set the heading on the binoculars to zero with the ship’s bow based on a landmark very far away.  We could not zero them the day before, because there was not a landmark far enough away to get an accurate reading.

The Gordon Gunter is one of the larger ships in the NOAA fleet according to several of the scientists who have been on many cruises.  It took me a while to figure out where all of the doors go and how they open.  I did not realize how hard it was to open some of the doors.  According to the XO, the doors are hard to open because of the pressure vacuum that exists in the house of the ship.  There is not really a reason for the vacuum to exist.  It is just the nature of the ship.

Life on board the Gordon Gunter has been very interesting for the first day.  Before leaving port, we had a fleet inspection.  We had to do all of our emergency drills.  Safety is very important on a ship.  We had to do a fire emergency drill where everyone had to meet at a muster station and be accounted for by one of the NOAA officers.  Then we had to do an abandon ship drill.  Then once we got sailing a short time, we had to do a man over board drill.

Donning the immersion suit in case of an abandon ship order was not a thrill for me but was comical in retrospect.  I am only 4’ll”, and the immersion suit I was given is made for someone who is over six feet tall.  When I tried on the suit, I had two feet of immersion suit left at the bottom.  When the NOAA officer came to inspect, he said I definitely needed a smaller suit.

One of the best features of my cruise so far has definitely got to be the galley.  The Gordon Gunter has the best cook in Miss Margaret.  She is the best and makes awesome food.  She has made cream cheese from scratch.  She makes the best smoothies.  I can only imagine what we are going to be getting for the rest of the cruise.

Did You Know?

All marine mammals, including the beaked whales, are protected under the Marine Mammal Protection Act.

Check out this website on what the law states and what it protects:

https://www.fisheries.noaa.gov/topic/laws-policies#marine-mammal-protection-act

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Joan Shea-Rogers: Do You Hear What They Hear, July 8, 2018

NOAA Teacher at Sea

Joan Shea-Rogers

Aboard NOAA Ship Oscar Dyson

July 1-22, 2018

Mission: Walleye Pollock Acoustic Trawl Survey

Geographic Area of Cruise: Eastern Bering Sea

Date: July 8, 2018

Weather Data from the Bridge

Latitude: 53º N

Longitude: 166ºW

Sea Wave Height: 1.5 feet

Wind Speed: 25 Knots

Wind Direction: SW

Visibility: 15 miles

Air Temperature: 52ºF

Water Temperature: 46º F

Barometric Pressure: 1010.61mb

Sky: Overcast

Science and Technology Log

What kinds of fish live in the Bering Sea? How many pollock are in the Bering Sea? Where are the pollock in the Bering Sea? How big are the pollock in the Bering Sea?

Those are just a few of the questions that the fisheries biologists on NOAA Ship Oscar Dyson work to answer during each voyage. In my last blog, I talked about the need to manage the pollock fishery in order to protect this important ocean resource because it provides food for people all over the world. It is important, then, to be able to answer the above questions, in order to make sure that this food source is available each year.

How do they do it? There are two main sources of information used in the Acoustics-Trawl (or Echo Integration Trawl) survey to determine the abundance and distribution of pollock in a targeted area of the Bering Sea. One is acoustics data, and the other is biological-trawl data.

Acoustics:

Acoustic data is continuously collected along a series of parallel transects with a Simrad EK60 scientific echo integration system incorporating five centerboard-mounted transducers (18-, 38-, 70-, 120-, and 200- kHz). In other words: There are 5 sound wave producers (transducers) attached to the bottom of the ship, each one emitting sound waves at different frequencies. This allows scientists to look at different organisms in the water column. Different types of organisms reflect different amounts of energy at different frequencies. The amount of acoustic energy reflected by an individual animal is called the target strength, and is related to the size and anatomy of the species. For example, a fish with a swimbladder (like pollock) reflects more energy than a fish without a swimbladder because its properties are very different from the surrounding water. Some ocean dwelling organisms don’t have swim bladders. Flatfish stay on the bottom so they don’t need the buoyancy. Floating organisms like jellyfish don’t have them. These organisms will look differently than pollock on an echogram because they have a smaller target strength.

Transducer
Transducer

Transducers convert mechanical waves (sound waves) into an electrical signal and vice versa (like both a loudspeaker and a microphone combined). They contain piezoelectric materials sensitive to electricity and pressure: if a voltage is applied to them, they make a pressure or sound wave (transmit), and when a sound wave passes over them, it produces a voltage (receive). When a sound wave (echo from a fish) is received, electoral signal is sent to a computer, which displays the signals as pixels of varying colors as the ship moves along (depth changes up and down on the left of the image, and time and location changes along the bottom of the image). This datum is used to estimate the number and type of fish in the water column, and to determine where the ship should fish next.

The size and colors on the images (called echograms) represent the backscatter at different depths and is related to the density of fish and their target strength. But, since they are dots on a screen, specific identification is not possible. The scientists assume certain strong signals are pollock based on the information they have but, those dots could be other fish. To determine what kind of fish are in the water column at this location, how many are there, and how big they are, other data must be obtained. Biological Trawl Data provides that additional information. More about that in my next blog post……I bet you can’t wait!

Personal Log

The Calm Before the Storm:

So far my trip has been smooth sailing, literally. As NOAA Ship Oscar Dyson sails across the Bering Sea there is a bit of rocking the ship experiences at all times. This is easy enough for one to get used to and sometimes it even becomes comforting, like being rocked to sleep as a child. You adjust to the motion. Over the past couple of days I have been hearing talk of a storm coming our way. On a ship, there are many preparations that occur in order to get ready for a storm. Many items are always secured, such as shelves that have a wall in front so that things don’t fall off. There are “handle bars” in showers and next to toilets (think about that). Along hallways and stairways there are handrails on each side. Mini refrigerators in staterooms are bolted to walls. In fact most things are bolted to walls or stored in containers that are bolted to the wall. In the mess hall (dining room) condiments on tables are in a box so they can’t slide off.

Why do you think this coffee mug is shaped like this (wider at the bottom than the top)?

 

At-Sea Coffee Mug
At-Sea Coffee Mug

Ans. The wider bottom of the mug above prevents it from sliding as the ship rocks.

Our bulletin board reminds us to secure for bad weather. This morning, I put small items in drawers, stowed books on shelves and packed my equipment (phone, laptop, camera, chargers and small items in a backpack that can be safely secured in my locker (the “closet” in my stateroom).

In talking to my shipmates with at sea experience, I am getting lots of helpful hints about storm preparations and strategies to use during the storm. Here are some of those suggestions:

*always hold on to railings with both hands when walking or going up steps. At all other times, remember to keep one hand for you (to do whatever you are doing) and one hand for the ship (to hold on).

*keep something in your stomach at all times, even if you are not feeling well

*eat saltines

*drink lots of water

*when sleeping in your bunk, place pillows between you and the edge so as not to roll off (I will definitely follow this one, as I am on the top bunk) It also depends upon which direction the ship is rolling. Pillows may need to be put between your head and the wall to prevent head bumps

*go to the lower parts of the ship because the top part will sway more with the waves

I also have been wearing patches to prevent seasickness. Hopefully they will continue to help. Only time will tell how we weather the storm (pun intended). Let’s hope it moves through quickly.

 

 

 

 

 

 

 

 

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Lee Teevan: Getting Schooled in the Nature of Science, July 8, 2018

NOAA Teacher at Sea

Lee Teevan

Aboard NOAA Ship Oscar Dyson

July 1 – 21, 2018

Mission:  Pollock Acoustic-Trawl Survey

Geographic Area of Cruise: East Bering Sea

Date: 8 July 2018

Dutch Harbor, AK
This is a view approaching Dutch Harbor, AK.

 

Weather Data from the Bridge

Latitude: 66 N

Longitude:  166 W

Sea Wave Height: 2ft

Wind Speed: 25 knots

Wind Direction: SW

Visibility: 15 miles

Air Temperature: 52°F

Barometric Pressure: 1010.61 mb

Sky: overcast

Science and Technology Log

Although July has just begun, teachers are already anticipating the first day of school.  Like every science teacher, we launch our classes with the “Nature of Science” or the “Scientific Investigation.”  Unlike past years, I plan on contextualizing these topics by showing my students the  “scientific investigation in action”  by describing how scientists aboard the Oscar Dyson studying eastern Bering Sea pollock populations apply the scientific method in their research.

Dr. Patrick Ressler, Chief Scientist
Dr. Patrick Ressler, Chief Scientist

To better understand how scientists “do science,” I had a conversation with Dr. Patrick Ressler, our Chief Scientist, about this topic. Dr. Ressler has been involved with the Pollock Acoustic Trawl Survey for many years and stresses that this ongoing research is a way to monitor change over time with pollock populations and to set quotas for commercial fisheries.  He shared his ideas about science and how it is a way to understand natural phenomena through testing. In biological research, however, it is harder to assess the outcomes because of the potential effects of outside factors.  That is why scientists refine their experiments to get “closer to the truth.”  Even being “wrong” about some ideas is beneficial because it facilitates opportunities to learn more. Scientists give testable ideas, or hypotheses, the chance to be wrong through repeated trials.

It was a circuitous path that Dr. Ressler took to become a scientist.  He studied environmental science and creative writing as an undergraduate, but after a semester abroad learning nautical science, he decided to study oceanography as a graduate student.  For his graduate studies, Dr. Ressler focused on acoustics and has worked on Pacific hake populations along the west coast of the U.S.  For the past 16 years, he has worked with NOAA as a Chief Scientist whose responsibilities include being a point of contact between the ship’s commanding officer and the management supervisor on land.  He has supported NOAA’s Teacher at Sea program because he feels that a good science teacher can better cultivate and inspire future scientists.

Screen with Acoustics Data
The screen displaying acoustics data is always monitored.

The  scientists on the Oscar Dyson have varied academic specialties, yet they are collaborating on the Pollock Acoustic Trawl Survey by contributing their expertise.  Dr. Ressler and Dr. Chris Bassett have been monitoring the acoustics on this expedition.  The acoustic system was most patiently explained to Joan and me by Dr. Bassett.

 

Dr. Chris Bassett
Dr. Chris Bassett, Ocean Acoustics Engineer

On the Oscar Dyson, there are 5 transducers producing vibrations on the drop keel of the boat.  Cables are attached that can lower this drop keel to 9.2 meters below so that storms will not interfere with the acoustics. These cables connect the drop keel to the five boxes in the survey room. Voltage signals are sent to the transceiver, which in turn creates a pressure wave.  When the signal is sent into the water, some sound bounces back. The pressure waves reflected back to the transducer are converted to an electrical signal and recorded by the computer. For the sound wave to scatter off something, it must have a density or sound speed different from that of the surrounding water. The larger the differences in the properties of the animals from the surrounding water, the more sound will generally be reflected by an animal. As a result, animals with ‘swim bladders’ (an organ inside their body containing air) will generally scatter more sound than animals without them.

When one of the transducers sends out a wave, the wave spreads out as it moves from the ship and it may encounter fish.  To assess the number of fish present, the total amount of acoustic energy, the volume of water, the range, and the echo expected from a single fish must be measured or estimated.

The acoustics translate into an ongoing screen display which is observed by both Dr. Ressler and Dr. Bassett in the acoustics lab.  The data displayed allows the scientists to decide whether a net sample is needed.

These scientists adhere to the scientific method so that they can make strong conclusions about their data. The acoustics portion is but one part of this ongoing research.  The trawls, after which we measure the length and mass of each fish, is a means of supporting the data from the acoustics portion. There are also cameras attached to the net so that the scientists can verify the type and abundances of fish species at each sampling transect. By corroborating findings in acoustics with the data from the trawls, these scientists can use their combined data to give greater insight on pollock populations and abundances.

Personal Reflection

I am in awe of people who do what they love for a career.  The scientists with whom I spoke convey their passion for their areas of expertise and are willing to share their knowledge.  These scientists have made me aware of outside resources so that I can learn more about the topic. Collaboration is evident among these scientists as each works to illuminate an aspect of the pollock population.  Together, their work sheds light on pollock dynamics.

Marine Careers

Sandi Neidetcher, a research fishery biologist at the NOAA’s Alaska Fishery Wildlife Center
Sandi Neidetcher, a research fishery biologist at the NOAA’s Alaska Fishery Wildlife Center, holds a bag of pollock ovaries.

Scientists aboard the Oscar Dyson participate in the Pollock Acoustic Trawl Survey research as well as projects of their own.  Sandi Neidetcher, a research fishery biologist at the NOAA’s Alaska Fishery Wildlife Center, is investigating the reproductive biology of pollock and cod.  According to Sandi, the reproductive biology of pollock is important for assessing the stock. By carrying out data collection of pollock length and otolith analysis, scientists can determine whether 50% of the stock is mature.  For pollock, using the otolith analysis is a good indicator of age. Otoliths are made of calcium carbonate and are found in the fish’s inner ear and otoliths have annual growth rings, which allows for scientists to accurately assign their ages.  Since pollock is a commercial fish, it’s important to know how many of the fish are capable of reproducing and using this data, set quotas commercial fishing.   Another facet in researching pollock populations is determining where and when pollock spawn as well as the frequency of spawning.  Sandi has been studying pollock, in addition to other commercially caught species, for many years as a commercial fishery observer.  Currently, she is sampling pollock ovary tissue to determine fecundity, or fertility, of the population for stock assessment.

Sandi advises high school students who think they’d enjoy this type of career to get a college degree in biology.  She also encourages them to network and apply for internships.  Effusive when recounting her career in research, Sandi is equally enthusiastic discussing her horse and misunderstood dog.

Did you know?

Otoliths aid fish like pollock in balance and acceleration.

 

Something to think about….

What are some factors that might affect the growth of otoliths?

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Brad Rhew: The Sounds of the Sea, July 31, 2017

NOAA Teacher at Sea

Brad Rhew

Aboard NOAA Ship Bell M. Shimada

July 23 – August 7, 2017

 

Mission: Hake Fish Survey

Geographic Area of Cruise: Northwest Pacific Ocean, off of the coast of Oregon

Date: July 31, 2017

 

Weather Data from the Bridge

Latitude: 44 49.160 N
Longitude 124 26.512

Temperature: 59oF
Sunny
No precipitation
Winds at 25.45 knots
Waves at 4-5ft

 

Science and Technology Log

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Inside the acoustics lab

The scientists on the Hake survey project are constantly trying to find new methods to collect data on the fish. One method used is acoustics. Scientists Larry Hufnagle and Dezhang Chu are leading this project on the Shimada. They are using acoustics at a frequency of 38 kHz to detect Pacific Hake. Density differences between air in the swimbladder, fish tissue, and the surrounding water allows scientists to detect fish acoustically.

The purpose of the swim bladder in a fish is to help with the fish’s buoyancy. Fish can regulate the amount of gas in the swim bladder to help them stay at a certain depth in the ocean. This in return decreases the amount of energy they use swimming.

TAS Rhew 7-31 echosounder
The screen shows the data collected by the echosounder at different frequency levels.

Larry and Chu are looking at the acoustic returns (echoes) from 3 frequencies and determining which are Hake. When the echosounder receives echoes from fish, the data is collected and visually displayed. The scientists can see the intensity and patterns of the echosounder return and determine if Hake are present.

The scientists survey from sunrise to sunset looking at the intensity of the return and appearances of schools of fish to make the decisions if this is an area to fish.

TAS Rhew 7-31 scientists Larry and Chu
Scientists Larry Hufnagle (left) and Dezhang Chu (right) monitor the nets and echosounder while fishing for hake.

The ultimate goal is to use this data collected from the echosounder to determine the fish biomass. The biomass determined by the survey is used by stock assessment scientist and managers to manage the fish stock.

Personal Log

Everyday aboard the Shimada is a different experience. It has been amazing to be able to go between the different research labs to learn about how each group of scientists’ projects are contributing to our knowing more about Hake and marine ecosystems. My favorite part so far has been helping with the sampling of Hake. Some people might find dissecting fish after fish to determine length, sex, age, and maturity to be too much. However, this gives me an even better understanding and respect for what scientists do on a daily basis so we can have a better understanding of the world around us. We have also caught other fascinating organisms that has helped me explore other marine species and learn even more about their role in the ocean.

Even though the wind is a little strong and the temperatures are a little chilly for my southern body I wouldn’t trade this experience for anything…especially these amazing sunsets…

TAS Rhew 7-31 sunset
View of sunset over the Pacific Ocean from NOAA Ship Bell M. Shimada

Did You Know?

Before every fishing operation on the boat we must first do a marine mammal watch. Scientists and other crew members go up to the bridge of the boat to see if any mammals (whales, seals, dolphins) are present near the boat. This is to help prevent these animals from being harmed as we collect fish as well as making sure we are not running a risk of these mammals getting caught in the fishing nets.

Fascinating Catch of the Day!

Today’s fun catch in the net was a Brown Catshark! These creatures are normally found in the deeper parts of the Pacific Ocean. They are typically a darker brown color with their eyes on the side of their head. Their skin is very soft and flabby which can easily lead to them being harmed. They have two dorsal fins and their nostrils and mouth on the underside of their body. One of the sharks we caught was just recently pregnant.

Two brown catsharks
Catsharks have two dorsal fins (on their backs)
Catsharks’ nostrils and mouths are on the undersides of their bodies
Catshark egg sacks

 

TAS Rhew 7-31 catshark egg sack string
This catshark was recently pregnant; the yellow stringy substance is from an egg sack.

Notice to yellow curly substance coming out of the shark? That is from the egg sac. Sharks only produce one egg sac at a time. It normally takes up to a full year before a baby shark to form!

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Staci DeSchryver: Things We Deliberately Throw Overboard Part Deux: The Ocean Noise Sensor July 20, 2017

NOAA Teacher At Sea

Staci DeSchryver

Aboard Oscar Elton Sette

July 6 – Aug 2

Mission:  HICEAS Cetacean Study

Geographic Area:  Northwest Hawaiian Island Chain, Just past Mokumanamana (Necker Island)

Date:  July 20, 2017

Weather Data from the Bridge:

Science and Technology Log:

As promised in Blog Post #3, I mentioned that “Thing number four we deliberately throw overboard” would have a dedicated blog post because it was so involved.  Well, grab some popcorn, because the time has arrived!

Thing number 4 we deliberately throw over the side of a ship does not get thrown overboard very often, but when it does, it causes much hubbub and hullaballoo on the ship.  I had the unique opportunity to witness one of only ten ocean noise sensors that are deployed in US waters come aboard the ship and get redeployed.  These sensors are found all over US waters – from Alaska to the Atlantic.  One is located in the Catalina Marine Sanctuary, and still others are hanging out in the Gulf of Mexico, and we are going to be sailing right past one!  To see more about the Ocean Noise Sensors, visit the HICEAS website “other projects” tab, or just click here.  To see where the Ocean Noise Recorders are, click here.

The Ocean Noise Sensor system is a group of 10 microphones placed in the “SOFAR” channel all over US waters.  Once deployed, they collect data for two years in order to track the level of ocean noise over time.  It’s no secret that our oceans are getting louder.  Shipping routes, oil and gas exploration, and even natural sources of noise like earthquakes all contribute to the underwater noise that our cetacean friends must chatter through.  Imagine sitting at far ends of the table at a dinner party with a friend you have not caught up with in a while.  While other guests chat away, you and the friend must raise your voices slightly to remain in contact.  As the night progresses on, plates start clanging, glasses are clinking, servers are asking questions, and music is playing in the background.  The frustration of trying to communicate over the din is tolerable, but not insurmountable.  Now imagine the host turning on the Super Bowl at full volume for entertainment.  Now the noise in the room is incorrigible, and you and your friend have lost all hope of even hearing a simple greeting, let alone have a conversation.  In fact, you can hardly get anyone’s attention to get them to pass you the potatoes.  This is similar to the noise levels in our world’s ocean.  As time goes on, more noise is being added to the system.  This could potentially interfere with multiple species and their communications abilities.  Calling out to find a mate, forage for food, or simply find a group to associate with must now be done in the equivalent din of a ticker-tape parade, complete with bands, floats, and fire engines blaring their horns.  This is what the Ocean Noise Sensor is hoping to get a handle on.   By placing sensors in the ocean to passively collect ambient noise, we can answer two important questions:  How have the noise levels changed over time?  To what extent are these changes in noise levels impacting marine life?   

Many smaller isolated studies have been done on ocean noise levels in the past, but a few years ago, scientists from Cornell partnered with NOAA and the Pacific Islands Fisheries Science Center (PIFSC) and the Pacific Marine Environmental Lab to streamline this study in order to get a unified, global data source of ocean noise levels.  The Pacific Marine Environmental Lab built a unified sound recording system for all groups involved in the study, and undertook the deployments of the hydrophones.  They also took on the task of processing the data once it is recovered.  The HICEAS team is in a timely and geographical position to assist in recovery of the data box and redeploying the hydrophone.   This was how we spent the day.

The recovery and re-deployment of the buoy started just before dawn, and ended just before dinner.

 Our standard effort of marine mammal observation was put on hold so that we could recover and re-deploy the hydrophone.  It was an exciting day for a few reasons – one, it was definitely a novel way to spend the day.  There was much to do on the part of the crew, and much to watch on the part of those who didn’t have the know-how to assist.  (This was the category I fell in to.)

At dawn, an underwater acoustic command was sent to the depths to release a buoy held underwater attached to the hydrophone.  While the hydrophone is only 1000m below the surface seated nice and squarely in the SOFAR channel, the entire system is anchored to the ocean floor at a depth of 4000m.  Once the buoy was released, crew members stationed themselves around the ship on the Big Eyes and with binoculars to watch for the buoy to surface.  It took approximately 45 minutes before the buoy was spotted just off our port side.  The sighting award goes to CDR Stephanie Koes, our fearless CO.  A crewmember pointed out the advancement in our technologies in the following way:  “We can use GPS to find a buried hydrophone in the middle of the ocean…and then send a signal…down 4000m…to a buoy anchored to the ocean floor…cut the buoy loose remotely, and then actually have the buoy come up to the surface near enough to the ship where we can find it.”  Pretty impressive if you think about it.

The buoy was tied to the line that is attached to the hydrophone, so once the buoy surfaced, “all” we had to do was send a fast rescue boat out to retrieve it, bring the buoy and line back to the ship, bring the crew safely back aboard the ship, hook the line up through a pulley overhead and back to a deck wench, pull the line through, take off the hydrophone, pull the rest of the line up, unspool the line on the wench to re-set the line, re-spool the winch, and then reverse the whole process.

Watching the crew work on this process was impressive at least, and a fully orchestrated symphony at best.  There were many tyings of knots and transfers of lines, and all crew members worked like the well-seasoned deck crew that they are.  Chief Bos’n Chris Kaanaana is no stranger to hauling in and maintaining buoys, so his deck crew were well prepared to take on this monumental task.

Much of the day went exactly according to plan.  The buoy was safely retrieved, the hydrophone brought on board, the lines pulled in, re-spooled, and all sent back out again.  But I am here to tell you that 4000m of line to haul in and pay back out takes. A Long. Time.  We worked through a rainstorm spooling the line off the winch to reset it, through the glare of the tropical sun and the gentle and steadfast breeze of the trade winds.  By dinner time, all was back in place, the buoy safely submerged deep in the ocean waters, waiting to be released again in another two years to repeat the process all over again.  With any luck, the noise levels in the ocean will have improved.  Many commercial vessels have committed to adopting “quiet ship” technology to assist in the reduction of noise levels.  If this continues to improve, our cetacean friends just might be able to hear one another again at dinner.

 

Personal Log

So, I guess it’s pretty fair to say that once you’re a teacher, you’re always a teacher.  I could not fully escape my August to May duties onboard, despite my best efforts.  This week, I found myself on the bridge, doing a science experiment with the Wardroom (These are what all of the officers onboard as a group are called).   How is this even happening, you ask?  (Trust me, I asked myself the same thing when I was in the middle of it, running around to different “lab groups” just like in class.)  Our CO, CDR Koes, is committed to ensuring that her crew is always learning on the ship.

 If her staff do not know the answer to a question, she will guide them through the process of seeking out the correct answer so that all  officers learn as much as they can when it comes to being underway –  steering the ship, preparing for emergencies, and working with engineers, scientists, and crew.  For example, I found out that while I was off “small-boating” near Pilot Whales, the Wardroom was busy working on maneuvering the ship in practice of man overboard scenarios.  She is committed to ensuring that all of her staff knows all parts of this moving city, or at a minimum know how to find the answers to any questions they may have.  It’s become clear just how much the crew and the entire ship have a deep respect and admiration for CDR Koes.  I knew she was going to be great when we were at training and word got out that she would be the CO of this Leg on Sette and everyone had a range of positive emotions from elated to relieved to ecstatic.

As part of this training, she gives regular “quizzes” to her staff each day – many of them in good fun with questions for scientists, crew, engineers, and I.  Some questions are nautical “things” that the Wardroom should know or are nice to know (for example, knowing the locations of Material Safety Data Sheets or calculating dew point temperatures), some questions are about the scientific work done onboard, while others are questions about personal lives of onboard members.

docandbromineDES_4437.JPG
The Chief Medical Officer, “Doc” gives a lesson on water quality testing.

 It has been a lot of fun watching the Wardroom and Crew seek out others and ask them where they live while showing them their “whale dance” to encourage sightings.  It has exponentially increased the interactions between everyone onboard in a positive and productive way.

The other teaching element that CDR Koes has implemented is a daily lesson each day from Monday to Friday just after lunch.  All NOAA Officers meet on the bridge, while one officer takes the lead to teach a quick, fifteen minute lesson on any topic of their choosing.  It could be to refresh scientific knowledge, general ship operations, nautical concepts, or anything else that would be considered “good to know.”

chiefengineerDES_4589.JPG
The Chief Engineer gives a rundown on the various ship emergency alarms.

 This sharing of knowledge builds trust among the Wardroom because it honors each officer’s strong suits and reminds us that we all have something to contribute while onboard.

I started attending these lunchtime sessions and volunteered to take on a lesson.  So, this past Tuesday, I rounded up some supplies and did what I know best – we all participated in the Cloud in a Bottle Lesson!

sextantDES_4607.JPG
Here I am learning to use a sextant for navigation.

The Wardroom had fun (I think?) making bottle clouds, talking about the three conditions for cloud formation, and refreshing their memories on adiabatic heating and cooling.  It was a little nerve wracking for me as a teacher because two of the officers are meteorologists by trade, but I think I passed the bar.  (I hope I did!)

groupworkbottlesDES_4329.JPG
Teaching about adiabatic cooling with the the Cloud in a Bottle Demo with the Wardroom!

It was fun to slide back into the role of teacher, if only for a brief while, and served as a reminder that I’m on my way back to work in a few weeks!  Thanks to the Wardroom  for calling on me to dust up my teacher skills for the upcoming first weeks of school!

JoshandTimDES_4325.JPG
ENS Holland and ENS Frederick working hard making clouds.

 

 

 

 

 

 

 

 

 

crew with bottlesDES_4340.JPG

Facebook Asks, DeSchryver Answers

I polled all of my Facebook friends, fishing (ha ha, see what I did there?) for questions about the ship, and here are some of the questions and my answers!

 

Q:   LC asks, “What has been your most exciting moment on the ship?”

It’s hard to pick just one, so I’ll tell you the times I was held at a little tear:  a) Any sighting of a new species is a solid winner, especially the rare ones  b) The first time I heard Sperm Whales on the acoustic detector c) The first time we took the small boat out for UAS operations….annnndddd d) The first time I was on Independent Observation and we had a sighting!

DES_3739.JPG
A group of Melon-Headed Whales, or PEPs, cruise along with the ship.

Q:  JK asks, “What are your thoughts on the breakoff of Larsen C?  And have there been any effects from the Alaskan quake and tsunami?”

We’re actually pretty isolated on board!  Limited internet makes it hard to hear of all the current events.  I had only briefly heard about Larsen C, and just that it broke, not anything else.  I had no clue there was a quake and tsunami!  But!  I will tell a cool sort of related story.  On Ford Island, right where Sette is docked, the parking lot is holding three pretty banged up boats.  If you look closely, they all have Japanese markings on them.  Turns out they washed up on Oahu after the Japan Tsunami.  They tracked down the owners, and they came out to confirm those boats were theirs, but left them with NOAA as a donation.  So?  There’s tsunami debris on Oahu and I saw it.

 

Q:  NG asks, “Any aha moments when it comes to being on the ocean?  And anything to bring back to Earth Science class?”

So many aha moments, but one in particular that comes to mind is just how difficult it is to spot cetaceans and how talented the marine mammal observers are! They can quite literally spot animals from miles away!  There are a lot of measures put in place to help the marine mammal observers, but at the end of the day, there are some species that are just tougher than nails to spot, or to spot and keep an eye on since their behaviors are all so different.  And as far as anything to bring back to our class?  Tons.  I got a cool trick to make a range finder using a pencil.  I think we should use it!

 

Q:  MJB asks, “Have you had some peaceful moments to process and just take it all in?”

Yes.  At night between the sonobuoy launches, I get two miles of transit time out on the back deck to just absorb the day and be thankful for the opportunities.  The area of Hawai’i we are in right now is considered sacred ground, so it’s very powerful to just be here and be here.

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These sunsets will give Colorado sunsets a run for their money.  No green flash in Colorado = point awarded to Hawai’i.

 

Q:  SC asks, “What souvenir are you bringing me?”

Well, we saw a glass fishing float, and we tried to catch it for you, but it got away.

Q:  LC asks, “What’s the most disgusting ocean creature?”

Boy that’s a loaded question because I guarantee if I name a creature, someone out there studies it for a living.  But! I will tell you the most delicious ocean creature.  That would be Ono.  In sashimi form.  Also, there is a bird called a Great Frigate bird – it feeds via something called Klepto-parasitism, which is exactly how it sounds.  It basically finds other birds, harasses them until they give up whatever they just caught or in some cases until it pukes, and then it steals their food.  So, yeah.  I’d say that’s pretty gross.  But everyone’s gotta eat, right?

Q:  KI asks, “Have you eaten all that ginger?”

I’m about two weeks in and I’m pretty sure I’ve eaten about a pound. I’m still working on it!

Q:  HC asks, ”Have you seen or heard any species outside of their normal ocean territory?”

Sort of.  Yesterday we saw Orca!  They are tropical Orca, so they are found in this area, but they aren’t very common.  The scientific team was thinking we’d maybe see one or two out of the entire seven legs of the trip, and we saw some yesterday!  (I can’t say how many, and you’ll find out why in an upcoming post.)  We have also seen a little bird that wasn’t really technically out of his territory, but the poor fella sure was a little far from home.

Q:  JPK asks, “What kinds of data have you accumulated to use in a cross-curricular experience for math?”

We can do abundance estimates with a reasonably simplified equation.  It’s pretty neat how we can take everything that we see from this study, and use those numbers to extrapolate how many of each species is estimated to be “out there.”

Q: AP asks, “What has surprised you about this trip?”

Many, many things, but I’ll mention a couple fun ones.  The ship has an enormous movie collection – even of movies that aren’t out on DVD yet because they get them ahead of time!  Also? The food on the ship is amazing.  We’re halfway through the trip and the lettuce is still green.  I have to find out the chef’s secret!  And the desserts are to die for.  It’s a wonder I haven’t put on twenty pounds.  The crew does a lot of little things to celebrate and keep morale up, like birthday parties, and music at dinner, and shave ice once a week.  Lots of people take turns barbecuing and cooking traditional foods and desserts special to them from home and they share with everyone.  They are always in really high spirits and don’t let morale drop to begin with, so it’s always fun.

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Celebrating Engineer Jerry’s Birthday.

Q:  TS asks, “What’s the most exciting thing you’ve done?”

I’ve done lots of exciting things, but the one thing that comes to mind is launching on the small boat to go take photos of the pilot whales.  Such a cool experience, and I hope we get good enough weather to do it again while we’re out here!  Everything about ship life is brand new to me, so I like to help out as much as I can.  Any time someone says, “Will you help with this?” I get excited, because I  know I’m about to learn something new and also lend a hand. 

 

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Staci DeSchryver: Listening with Your Eyes – How the Acoustics Team “Sees” in Sound, July 10, 2017

NOAA Teacher at Sea

Staci DeSchryver

Aboard NOAA Ship Oscar Elton Sette

July 6 – August 2, 2017

Mission:  HICEAS Cetacean Study

Geographic Area:  Kona Coast, Hawaii

Date:  July 10, 2017

Weather Data from the Bridge:

TAS DeScrhryver_weather data
Location and Weather Data

 

Science Log

While the visual team is working hard on the flying bridge, scanning the waters for our elusive cetacean friends, acoustics is down in the lab listening for any clues that there might be “something” out there.

TAS DeSchryver array
The hydrophone array is a long microphone pulled behind the ship

At any given time, two acousticians are listening to the sounds of the ocean via a hydrophone array. This array is a long microphone pulled behind the ship as she cuts through the water.  When the acousticians hear a click or a whistle, a special computer program localizes (or determines the distance to) the whistle or the click.

But it’s not quite as simple as that. There’s a lot of noise in the ocean.  The array will pick up other ship noise, cavitation (or bubbles from the propeller) on our ship, or anything it “thinks” might be a cetacean.  The acoustics team must determine which sounds are noise and which sounds belong to a mammal.  What the acousticians are looking for is something called a “click train.” These are sound produced by dolphins when they are foraging or socializing and are a good indicator of a nearby cetacean. On the computer screen, any ambient noise shows up as a plotted point on an on-screen graph.  When the plotted points show up in a fixed or predictable pattern, then it could be a nearby cetacean.

The acousticians are also listening to the sounds on headphones.  When they hear a whistle or a click, they can find the sound they’ve heard on the plotted graph.  On the graphical representation of the sounds coming in to the hydrophone, the x-axis of the graph is time, and the y-axis is a “bearing” angle.  It will tell which angle off the ship from the front the noise is coming from.  For example, if the animal is right in front of the bow of the ship, the reading would be 0 degrees.  If it were directly behind the ship, then the plotted point would come in at 180 degrees.  With these two pieces of information, acousticians can narrow the location of the animal in question down to two spots on either side of the ship.  When they think they have a significant sound, the acousticians will use the information from the graph to localize the sound and plot it on a map.  Often times they can identify the sound directly to the species, which is an extraordinary skill.

Here’s where things go a little “Fight Club.”  (First rule of fight club?  Don’t talk about fight club.)  Once the acousticians localize an animal, they must determine if it is ahead of the ship or behind it.   Let’s say for example an acoustician hears a Pilot Whale.  He or she will draw a line on a computerized map to determine the distance the whale is to the ship using the data from the graph.

DeSchryver HICEAS-AC20
This is a “clean” localization of a marine mammal. Notice the two spots where the lines cross – those are the two possible locations of the mammal we are tracking. The ship is the red dot, the blue dots are the hydrophone as it is towed behind the ship.

Because the hydrophones are in a line, the location provided from the array shows on the left and the right sides.  So, the map plots both of those potential spots.  The two straight lines from the ship to the animal make a “V” shape.  As the ship passes the animal, the angle of the V opens up until it becomes a straight line, much like opening a book to lay it flat on the table and viewing how the pages change from the side.  As long as the animal or animal group is ahead of the ship, the acousticians will alert no one except the lead scientist, and especially not the marine observers.  If a crew member or another scientist who is not observing mammals just so happens to be in the acoustics lab when the localization happens, we are sworn to secrecy, as well.  Sometimes an acoustician will send a runner to get the lead scientist to discreetly tell her that there is something out there.

TAS DeSchryver HICEAS-AC25
The screenshot on the left shows a series of spotted dolphin “click trains.” Notice the marks all in a line along the graph. The right photo shows the various localizations that the acoustics team has picked up from the click train graph. The red dot is the ship, the gray line is the “track line”, and the two blue dots behind the ship are the hydrophone arrays. Notice the V shape gradually goes to a straight line and then turns in the opposite direction.

 

This way, the lead scientist can begin the planning stages for a chase on the mammals to do a biopsy, or send the UAS out to get photos with the Hexacopter.  (More on this later.)

As the mammals “pass the beam” (the signal is perfectly on either side of the ship, and starting to make an upside down V from the ship), the acousticians can alert the visual team of the sighting.  As soon as everyone is aware the mammals are out there, either by sight or sound, the whole scientific group goes “off effort,” meaning we funnel our energy in to counting and sighting the mammals we have found.  When this happens, communication is “open” between the acoustics team and the visual team.  The visual team can direct the bridge to head in any direction, and as long as it’s safe to do so, the bridge will aid in the pursuit of the mammals to put us in the best position to get close enough to hopefully identify the species.  Today, one mammal observer had a sighting almost 6 miles away from the ship, and she could identify the species from that distance, as well!  Even cooler is that it was a beaked whale, which is an elusive whale that isn’t often sighted.   They have the capability of diving to 1000m to forage for food!

When the visual team has a sighting, the three visual observers who are on shift have the responsibility to estimate the group size.

TAS DeSchryver chris takes photos
Chris captures photos of Melon Headed Whales for Photo ID.

 

Here we go with Fight Club again – no one can talk to one another about the group sizes.  Each mammal observer keeps their totals to themselves.  This is so that no one can sway any other person’s opinion on group size and adds an extra element of control to the study.  It is off limits to talk about group sizes among one another even after the sighting is over. We must always be vigilant of not reviewing counts with one another, even after the day is done.  The scientific team really holds solid to this protocol.

Once the sighting is over, all parties resume “on effort” sightings, and the whole process starts all over again.

Now, you might be thinking, “Why don’t they just wait until acoustics has an animal localized before sending the mammal team up to look for it?

TAS DeSchryver ernesto big eyes
Ernesto on the “Big Eyes” during a Melon Headed Whale Visual Chase

Surely if acoustics isn’t hearing anything, then there must not be anything out there.”  As I am writing this post, the visual team is closing in on a spotted dolphin sighting about 6.5 miles away.  The acoustics did not pick up any vocalizations from this group.

TAS DeSchryver acoustics lab 2
Shannon and Jen in the acoustics lab “seeing” the sounds of the ocean.

This also happened this morning with the beaked whale.  Both teams really do need one another in this process of documenting cetaceans.  Further, the acoustics team in some cases can’t determine group sizes from the vocals alone.  They need the visual team to do that.  Each group relies on and complements one another with their own talents and abilities to conduct a completely comprehensive search.  When adding in the hexacopter drone to do aerial photography, we now have three components working in tandem – a group that uses their eyes to see the surface, a group that uses the ocean to “see” the sounds, and a group that uses the air to capture identifying photographs.  It truly is an interconnected effort.

 

Personal Log

I haven’t gotten the chance to discuss just how beautiful Hawai’i is.  I would think that it is generally understood that Hawai’i is beautiful – it’s a famed tourist destination in an exotic corner of the Pacific Ocean. But you have to see it to believe it.

TAS DeSchryver melon-headed whales
Melon-Headed Whales take an evening ride alongside the starboard side of Sette.

I’ve been lucky enough to see the islands from a unique perspective as an observer from the outside looking inland, and I just can’t let the beauty of this place pass without mention and homage to its stunning features.

Hawai’i truly is her own artist.  Her geologic features create the rain that builds her famed rainbows, which in turn gives her the full color palate she uses to create her own landscape.  The ocean surrounding the shores of Hawai’i are not just blue – they are cerulean with notes of turquoise, royal, and sage.  She will not forget to add her contrasting crimson and scarlet in the hibiscus and bromeliads that dot the landscape. At night when the moon shines on the waters, the ocean turns to gunmetal and ink, with wide swaths of brass and silver tracing the way back up to the moon that lights our path to the sea.  With time, all of her colors come out to dance along the landscape – including the sharp titanium white foam that crashes against the black cliffs along Kona.  And if a hue is errantly missed in her construction of the landscape, early morning showers sprout wide rainbows as a sign of good fortune, and as a reminder that she forgets no tones of color as she creates.

It is our responsibility to protect these waters, this landscape – this perfect artistry.  It is critically important to protect the animals that live in the ocean’s depths and the ones that cling to the island surface in their own corner of paradise.  I like to think that this study takes on this exact work.  By giving each of these species a name and identifying them to each individual group, we share with the world that these cetaceans are a family of their own with a habitat and a purpose.  When we “re-sight” whales that the team has seen in past studies, we further solidify that those animals have families and a home amongst themselves.   The photo identification team counts every new scar, marking, and change in these animals to piece together the story of their lives since they last met with the scientists.  Everyone on Oscar Elton Sette  talks about the new calves as if we were at the hospital with them on the day of their birth, celebrating the new life they’ve brought forth to continue their generations.  I like to think we all make a little room in the corner of our hearts for them as a part of our family, as well.

Did you know?

The Frigate bird has a Hawaiian name, “Iwa”, which means “thief.”  They call this bird “thief” because they steal prey right from the mouths of other birds!

 

“Spyhopping” is the act of a whale poking his head out of the water and bobbing along the surface.

 

It is legal for research ships to fish off the ship, so long as we eat what we catch while underway.  This led to the shared consumption of some delicious mahi mahi, fresh from the depths for lunch today.  Yes.  It was as good as it sounds.

 

Oscar Elton Sette knows how to celebrate!  Yesterday was Adam’s birthday, a marine mammal observer.  They decorated the mess in birthday theme, cranked up the dinnertime music, and the stewards made Adam his favorite – blueberry cheesecake for dessert!

 

Much of the crew likes to pitch in with food preparation.  The on ship doctor, “Doc”, makes authentic eastern dishes, and the crew made barbeque for everyone a few nights ago at dinner.

Posted on

Dawn White: Pinging for Populations, June 29, 2017

 

NOAA Teacher at Sea

 Dawn White

Aboard NOAA Ship the Reuben Lasker

June 19 – July 1, 2017

 

Mission: West Coast Sardine Survey

Geographic Area of Cruise: Pacific Ocean; U.S. West Coast

Date: June 29, 2017

 

Weather Data from the Bridge

Date: June 29, 2017                                                         Wind Speed: 7.7 kts

Time: 6:15 p.m.                                                                 Latitude: 4805.5N

Temperature: 12.7oC                                                      Longitude: 12520.07W

 

Science and Technology Log

The technology present on this ship is amazing and at the same time quite overwhelming.  These systems allow for data to be collected on a wide range of variables both continuously and simultaneously.  Below are a couple of photos of the acoustics room where multiple sensors are monitoring the feedback from sonar systems placed below the ship’s hull.  One of the acoustic probes sends out sound waves in a cone-like formation directly below the ship.  Another unit emits sound waves in a horizontal pattern.  The ship was designed to run as quietly as possible so as to not disturb the marine life present in the waters as the ship passes by and also to reduce the interference of the ship’s sounds with the acoustics feedback.

 

Acoustics technician Dan Palance manages multiple computers
Acoustics technician Dan Palance manages multiple computers

 

Acoustics technician Dan Palance managing the multiple computers that are constantly collecting data.

Multiple programs help to eliminate the “noise” received by the probes until all that remains are images that represent schools of fish and their location relative to the ocean floor.

 

Diagram of Multibeam Sonar System
Diagram of Multi-frequency scientific sounder

The images above were taken from a poster on board the Reuben Lasker. They illustrate the range of the water column surveyed by the various acoustic systems.

 

The “soundings” are received by the ship, processed and “cleaned up” using a series of program algorithms. The image below shows the feedback received from one of the systems.

Displays of feedback from an acoustics system

Once the background “noise” has been eliminated, the resulting image will show locations of fish, school size, and the depth (y axis) at which they can be found.

Graph of acoustic feedback, with background “noise” eliminated, depicting depth and size of fish schools

 

Extension question for my students reading this:  Approximately how deep are the schools of fish being picked up by the sonar at this location?

Acoustics aren’t the only tools used to try pinpoint the locations of the fish schools.  As I wrote about on an earlier blog, the CUFES egg sampler is used to monitor the presence of fish eggs in the waters that the ship passes over.  Water samples are analyzed every half hour.  If egg samples appear in an area where there is also a strong acoustics signal, then that may be a location the ship will return to for the night’s trawl.  The main focus of this trip is to monitor the anchovy and sardine populations, so extra attention is paid to the locations where those eggs appear in the samples.

Personal Log:

Each time we drop the net for an evening trawl it is always retrieved with a bit of suspense:  What’s going to be in the net this time?  How big is the haul?  Will we capture any of the key species or haul in something completely different?

I can honestly say that while on board there were no two hauls exactly the same.  We continued to capture large quantities of pyrosomes – unbelievable amounts.  Check out the net-tearing load we encountered one night.  We literally had to weigh them by the basketful!

Here I am getting ready to help unload this large catch.

TAS Dawn White prepares to help unload large catch

 

Net-tearing load of pyrosomes!

Above is the codend of the net filled with pyrosomes and fish.  A 5-basket sample was pulled aside for analysis.  The remainder was simply classified and massed.

While I was certainly don’t need to see another pyrosome any time soon, there were plenty of other times when some very unique species made an appearance!

Pacific Jack Mackerel

Solitary Common Salp

TAS Dawn White holds a Blue Shark

Dogfish Shark

Did you know?

The dogfish shark (pictured above) was one of about 50 or so that were caught in the same haul.  We had trawled through a school that was feeding on the small fish found at the ocean surface during the evening hours.  This is the same species of shark that is commonly provided to students for dissection.  Use the search terms “dogfish shark dissection” and see what you find!