NOAA Teacher at Sea Blog

August 5, 2026August 5, 2026

Stacey Morris: MVP & Investigating the Acoustic Trawl Method, August 3, 2026

NOAA Teacher at Sea

Stacey Morris

Aboard NOAA Ship Reuben Lasker

July 26-August 10, 2026

Mission: Integrated West Coast Pelagics Survey

Geographic Area of Cruise: West Coast Pacific Ocean

Date: August 3 , 2026

Weather Data from the Bridge

Latitude: 43° 06.4 ‘N

Longitude: 124°52.3 ‘W

Wind Speed: 25 kts

Air Temperature: 14.9 °C

Science and Technology Log

To understand more about the acoustic study component of our fish survey, I sat down with Kevin Stierhoff, Chief Scientist and Primary Investigator, and Brad Erisman, marine biologist, to see how our sonar mapping efforts integrate with the nightly trawling operations.

Interview Discussion with Kevin Stierhoff, Chief Scientist:

The Acoustic Trawl Methodology

Kevin: The acoustic trawl method is a globally recognized technique for surveying coastal pelagic species. By utilizing sonar, the ship can efficiently map expansive stretches of the seafloor and record precise echoes from fish populations. These instruments are highly calibrated and sensitive, providing us with accurate data on the biomass below. However, acoustics alone cannot identify the specific species creating the signal. To solve this, we conduct sonar surveys during the day when fish are schooling at depth, and then perform net trawls at night as they rise toward the surface. This nocturnal sampling allows us to determine the species and size composition without the fish avoiding the net as easily. By combining these datasets, we can apply the ratios found in our catches to the sonar echoes gathered during the day. This robust method is the primary tool for managing sardine and anchovy stocks along the West Coast.

photo of a screenshot of the display of the SX90 sonar readings with arrows labeling a bright red blob as a school of fish and a squiggly line as a fish track; this image may be in a textbook — Sonar image of fish school: Image credit NOAA

Historical Context

While simpler sonar and net surveys were conducted as early as the mid-1970s, the modern integrated approach used by the NOAA Southwest Fisheries Science Center in San Diego began in 2008. Since 2012, we have maintained a consistent schedule, performing these surveys at least once annually.

Observing Ecosystem Shifts

The marine environment has changed significantly since the surveys began. In 2012, sardines were the dominant species, but their numbers plummeted leading to the fishery’s closure in 2015. Conversely, northern anchovy and jack mackerel populations have surged, with anchovies remaining the most prevalent species we encounter today. Sardines have yet to show signs of a rebound following their crash a decade ago.

a metal tray filled with thin, silver fish all arranged to face the same direction — Anchovies brought up in one of our trawls this week

Environmental Drivers

There is much discussion regarding why these shifts occur. While fishing pressure reduced stocks in the past, current low levels are likely driven by environmental and biological factors, rather than active overfishing.

Leadership Roles at Sea

The structure of the scientific team ensures the integrity of the data collected. The Principal Investigators (PIs) are responsible for the overall coordination and quality of the long-term survey. On the ship, the Chief Scientist manages daily operations and leads the scientific party, coordinating with the PIs to ensure the survey’s objectives are met successfully.

Advanced Sonar Systems

photo of an illustration printed in a book or on a brochure of a white ship, its centerboard, and swaths of color emanating from the ship or the centerboard representing sound waves. printed on the image is this paragraph: "Multibeam Sonar System provides information on the biomass within the water column and on the type and topography of the seafloor. Drawing courtesy of Kongsberg-Simrad." — Acoustic sonar system under NOAA Reuben Lasker

The ship’s acoustic “eyes” are located on a retractable centerboard, or keel, beneath the hull. While in port, this keel is flush with the ship, but it is lowered once we reach deep water. The Reuben Lasker is equipped with an impressive array of six different sonar frequencies. Low frequencies, like the 18 kilohertz signal, penetrate deep into the ocean to map the seabed, while higher frequencies are better for detecting smaller organisms like krill in the upper water column. We primarily use the 38 kilohertz frequency to measure fish echoes. Anything in the water column with a different density than the surrounding seawater—whether it be a fish, squid, or the ocean floor—reflects sound waves that our instruments carefully measure.

six vertical panels showing backscatter readings at each depth over time, with each panel using a different frequency — Different sonar frequencies used to find fish

Omnidirectional and Multi-beam Sonars

Beyond the downward-looking sonar, we utilize an omnidirectional sonar mounted forward that scans in a radius around the ship. This helps us see fish near the surface that might be missed by the keel-mounted sensors. We also have multi-beam echo sounders, like the ME70 and MS70, which provide detailed three-dimensional views of fish schools and behavior. While these are invaluable for observing marine life, they are more difficult to calibrate for the precise biomass estimates provided by our primary systems.

photo of a computer screen displaying output from the ME70 - backscatter at different frequencies, and a sonar image — sonar image from ME70

photo of an illustration printed in a book or on a brochure depicting a ship at the surface and soundwaves emanating out from its hull; the waves surround a school of fish. — Image credit: NOAA

Survey Transects and Navigation

The survey follows a series of transects that span the U.S. continental shelf from Mexico to Canada. These lines generally extend at least 35 miles offshore to ensure we capture the full range of the species we are monitoring. Each transect provides a localized estimate of biomass, and by repeating these measurements across the entire coast, we can calculate a mean population estimate with statistical confidence. The spacing between these lines—currently 12.5 nautical miles—is a careful balance between our available time at sea and the need for scientific precision. While navigating perpendicular to the coast can sometimes lead to a rougher ride in the troughs of the waves, it remains the most efficient and scientifically sound way to sample across the varying densities of marine life.

simple political map of the west coast of the continental United States, ranging from the border of California and Mexico to Vancouver. small black lines extend out perpendicular to the coastline. each is labeled with a code. — transect lines for the Integrated West Coast Fisheries Survey:
Image Credit: NOAA

Did you Know?

The sonar system on the Reuben Lasker is so sensitive it can detect individual organisms based on their density relative to the water.

two side by side political maps of the western continental United States shown side by side to graph two different types of data by latitude: on the left, density of biomass fish species along the survey transect lines; on the right, proportions of species at sample locations along the transect lines — Density of biomass of fish species (left) and species proportions (right) –Image credit: NOAA

Interview with Brad Erisman, marine biologist about the use of the MVP

Brad: The precision of our acoustic survey relies heavily on the physical properties of the water we traverse. Factors such as temperature and density significantly influence the strength and travel speed of sonar echoes. While we calibrate our instruments in San Diego, the conditions change as we move north along the coast. To maintain the accuracy of our biomass estimates, we must continuously adjust our parameters to account for variations in sound absorption and velocity within the water column.

The Moving Vessel Profiler (MVP)

This is where the MVP, or Moving Vessel Profiler, becomes indispensable. We deploy this specialized probe to capture a comprehensive temperature profile of the water column. These real-time measurements allow us to calculate essential coefficients for our acoustic data. Along every transect, we perform multiple deployments to ensure we have representative environmental data. This constant fine-tuning allows us to produce the most reliable estimates of fish populations possible.

MVP is deployed via crane

Environmental Sensors

The MVP is a sophisticated tool, far more capable than a simple surface drifter. It is equipped with an array of sensors that measure salinity, chlorophyll levels, oxygen concentration, and sound speed. While a drifter only provides a surface snapshot, the MVP reveals the three-dimensional structure of the sea, highlighting fascinating features like thermoclines where warm, shallow water meets the colder, deeper ocean water.

Correlating Fish Patterns with Ocean Data

These environmental datasets help us explain the spatial and vertical distribution of the species we monitor. By collecting in situ data at the same fine scale as our sonar and trawl operations, we can identify correlations between habitat conditions and fish behavior. While satellite data provides a broad overview, the MVP gives us the high-resolution evidence needed to understand why schools appear in certain areas or why species patterns shift across different oceanographic breaks.

photo of a computer screen displaying output from the moving vessel profiler — MVP screen

Efficiency at Sea

The beauty of the Moving Vessel Profiler is in its name—it allows us to sample while the ship is in motion. A traditional Conductivity, Temperature, and Depth (CTD) cast involves a large cage lowered from a stationary ship, which would force us to halt our acoustic sampling. The MVP allows us to gather the necessary data without sacrificing valuable time. Although it doesn’t collect water samples or reach the extreme depths of a stationary cast, it provides exactly what we need to keep the survey on schedule.

A Three-Dimensional View of the Habitat

Oceanographers use these data points to build complex 3D models of the marine environment. These models are vital for understanding fish preferences; for instance, if sardines migrate further north, we can often trace that movement to a specific temperature preference, such as 15-20 C°-degree water, shifting with the currents. This helps us distinguish between a population decline and a simple change in habitat location.

Climate Signals and Regional Patterns

While large-scale climate signals like El Niño or La Niña are often monitored via satellite, our shipboard data helps define how these patterns manifest regionally. By looking at the data across the entire coast, we see the localized reflections of these massive basin-wide shifts, providing a clear picture of how the changing climate impacts our West Coast ecosystems.

close-up photo of a pile of dice of different numbers of sides — D & D dice

Personal Log

We’ve run into windy conditions after we crossed over the border into Oregon. We only were able to do one trawl last night before we had to call it a night due to rough waters. Tonight, we were on watch until midnight to see if things would calm down but it’s still too rocky. To fill the time, we are discovering the delightful world of Dungeons and Dragons, led by the artful storytelling of the Operations Officer, Mike Fuller.

It’s challenging walking down the hallways, and a large wave can scatter anything that isn’t well secured. Luckily the Dramamine is doing its trick and I haven’t felt queasy at all this week.

View of ocean swells out a porthole window

August 4, 2026August 4, 2026

Jo Slavitz: Expect the Unexpected, July 30, 2026

NOAA Teacher at Sea

Jo Slavitz

Aboard NOAA Ship Oscar Dyson

July 19th – August 10th

Mission: Summer Pollock Acoustic-Trawl Survey, Leg 3

Geographic Area of Cruise: Bering Sea, Alaska

Date: July 30, 2026

Weather Data from Bering Sea

Latitude: 58° 38.303’ N

Longitude: 176° 17.674’ W

Winds: SW at 9 mph

Air Temperature: 46.94° F (8.3° C)

“It is that range of biodiversity that we must care for – the whole thing – rather than just one or two stars.” – David Attenborough

Science and Technology Log

NOAA scientists conducting the Acoustic-Trawl survey are skilled at finding pollock, but even, so tiny amounts of other species also sometimes slip into the net. These unexpected creatures are called “bycatch.” Although not targeted, it doesn’t mean that these species are not important. A healthy pollock population depends on a complete and healthy ecosystem, so the science team also measures and takes data on these creatures before releasing most of them back to the water. Sometimes, the science team also gathers information about these species for other scientists on land conducting special projects for other programs. Here are some of the interesting fish that came in with trawls aboard Oscar Dyson on Leg 3.

Jellyfish

Outside of pollock, jellyfish have been the most frequent visitor to the trawl. Existing before dinosaurs, jellyfish trace their origin back over 500 million years, their closest relatives being corals and anemones. They are invertebrates (meaning they do not have a backbone) in the phylum Cnidaria, subphylum Medusozoa. Jellyfish are found around the planet in the world’s oceans and even in some fresh water ponds/lakes. Not a fish at all, jellies contain no brain, bones, gills or hearts. They are considered a keystone organism, one that holds the ecosystem together because it interacts with so many other species within the food web. Jellyfish’s main diet consists of tiny animals and plankton. They serve as food for sea turtles, fish, crabs, birds and even humans. Even though they can often sting, small animals will swim among jellies to hide from predators. So far we have seen 3 species of jellyfish in the trawls in the Bering Sea:

Chrysaora: The most common jellyfish found in the trawls this trip are by far Chrysaora. These stunning animals get their name from mythology. Chrysaor was the warrior child of Poseidon the sea god and Medusa, and his name means “adorned in gold” or “golden warrior.” It’s the perfect name for this golden beauty. Chrysaora are in the family commonly referred to as sea nettles. They can grow to reach up to 2’- 3’ in diameter. Chrysaora is typically found at depths up to 100 meters in the Bering and Arctic Seas. Since the 1990’s the total biomass of this species has been increasing. Biomass is the total amount of mass of an animal population in a specific area.

Jo, wearing overalls, long yellow gloves, and sunglasses, leans forward over a sorting table in the wet lab. On the table in front of her is a yellow-orange jellyfish that may be 3 feet in diameter. — Chrysaora Jellyfish

Aequorea: Less showy and bright than Chrysaora, Aequorea jellies are predominantly clear with a flat smooth disk-shaped bell. Its name is taken from the Latin words aequor “from the sea” and aequus “even, flat or level.” Their family is commonly known as crystal jellies. This family of jellyfish fascinates scientists because they contain photoproteins that allow them to fluoresce with bioluminescence. Bioluminescence is the ability for animals to create their own light. Animals such as backyard lightning bugs and deep-sea fish are also capable of this unique adaptation.

close-up view of a completely translucent jellyfish spread out on a white plastic measuring board. we can read the measuring line through the jellyfish; it extends from about 2.5 cm to about 13.5 cm. — Aequorea Jellyfish

Aurelia: Aurelia or moon jellyfish are one of the most widely distributed family of jellies. A. limbata, or brown moon jellies are native to the Bering Sea and coastal Alaska. They range in size from about 9 to 12 inches in diameter. They have a clear cup-shaped bell with brown to orange organs arranged in a circle around the center.

Fish

Pacific Cod: A relative of the Alaskan pollock, Pacific cod are also a cold water whitefish. Also similar to pollock, many people like to cook and eat cod, so this fish ended up as our guest in the mess later that night for dinner.

cooked fish filet plated with vegetables, topped with a lemon slice

A Pacific cod in sample basket; later, plated for dinner in the mess hall

Flathead Sole: As a bottom dweller, the flathead sole has both eyes on a single side of its head. His topside is a splotchy brown color, while his underside is a translucent white.

mottled brown right-eyed flatfish laid out against a white surface — Flathead sole

Chum Salmon: Though this one is not so big. Chum salmon are the second largest pacific salmon after chinook. Males of this species develop large canine-like fangs

one salmon in a green plastic basket — Chum Salmon

Smooth Lumpsucker: A deep-sea fish, the smooth lumpsucker has a slippery, scaleless skin. Look closely to see the circle on its underside. The pelvic fins in this species are modified to form a disk used to help secure the fish to ocean surfaces in fast moving waters.

a remarkably round fish held up in someone's glove hand tilted toward the ceiling to reveal the suction disk on its underside — Smooth lumpsucker

Try It on Dry Land

Although you may not be able to hitch a ride out to the Bering Sea for the pollock acoustic survey, you can create your own trawling simulation with a box of Trix cereal and a few kitchen materials.

Trix Trawl

Materials:

1 box Trix Cereal
1 cookie sheet or shallow baking pan
A ruler
Tape
1 Tbs measuring spoon or scoop
Data chart (downloadable pdf)

* Optional small kitchen scale

Instructions

Use ruler to measure and mark with tape both long sides of the cookie sheet in 2” segments. These are your transects lines that you will sample from.
Drag the tablespoon from the mark on one side to the corresponding mark on the opposite side. This is your trawl net. You may not touch the cereal with anything but the spoon.
Sort the cereal into groups of the same shape/color type and record on data sheet.
Repeat until all steps until transects are complete.

Did you get the same number for each shape/color?
Do you feel like it was an accurate representation for all the cereal in the box?
Did you find anything unexpected in the cereal box?
NOAA scientists also gather the weight for each species group. If you have a small kitchen scale you can weigh each shape/color group and record. Is the set with the most individual pieces also the heaviest?

Trix Trawl data Download

Happy Sampling!

Jo, wearing overalls, yellow gloves, and sunglasses, stands in the wet lab in front of stacks of plastic sample bins. She stretches her arms toward the camera to show off a large, yellow-orange chrysaora jelly. a few pollock are visible on the sorting table off to the side. — Jelly Love

August 4, 2026August 5, 2026

Stacey Morris: Get my Drift? August 2, 2026

NOAA Teacher at Sea

Stacey Morris

Aboard NOAA Ship Reuben Lasker

July 26-August 10, 2026

Mission: Integrated West Coast Pelagics Survey

Geographic Area of Cruise: West Coast Pacific Ocean

Date: August 2, 2026

Weather Data from the Bridge

Latitude: 42°29.6 ‘N

Longitude: 125°11.9’W

Wind Speed: 27 kts

Air Temperature: 15.8°C

Science and Technology Log

The day before I left for my trip aboard NOAA Reuben Lasker, I received an exciting email from the Teacher at Sea program. I was going to have the opportunity to participate in NOAA’s Adopt-a-Drifter Program, and I would be getting three drifter buoys that I would be releasing along our journey north along the coastline.

three drifting buoys sit on a metal table in the wet lab. each drifting buoy's surface float rests on its coiled up drogue. the surface float portions are covered in stickers and decorated with marker. we can see NOAA Teacher at Sea stickers, stickers from Churchhill High School, and drawings of octopus. — Three Drifters ready for deployment

A drifting buoy, frequently called a “drifter,” is designed primarily to track sea surface temperatures. They can also capture data on everything from winds and atmospheric pressure to salinity and wave height. As these buoys meander across the ocean, pushed along by currents, their internal sensors beam this information up to satellites circling overhead. By mapping their journey over time, scientists can piece together a detailed profile of how our oceans move.

screenshot from the Global Drifter Array world map showing the current position of 1,126 drifting buoys, color coded by deploying country. U.S. buoys are bright blue and the most numerous, especially in the Pacific Ocean. — Map of drift buoys and their respective deploying countries

To ensure it stays on track with the water rather than the wind, a drifter utilizes a “drogue,” which acts as an underwater sea anchor extending down about 20 meters (or 65 feet). This drogue is tethered to the surface float, ensuring they travel in tandem with the near-surface currents. Without that heavy drogue to steady it, a drifter would just be tossed about by the wind and waves, much like a beach ball skittering across the top of a swimming pool.

illustration of a drifting buoy above and below the surface of the ocean. arrows label: Surface Float - designed for moving on the surface with the currents, Antenna - The drifters transmit the data they collect as well as their position via satellite, Sensors - Sea Surface Temperature sensor and various measuring systems, Drogue - The buoys have some for of subsurface drogue or sea anchor — Drifting Buoy diagram. Image Credit: NOAA

Drifter information is vital for mapping worldwide ocean currents and eddies, validating satellite readings, and constructing complex weather and climate models. These sensors also help predict where pollutants might travel after a spill, how garbage moves through the ocean, and even help track the path of approaching hurricanes.

This data isn’t just for scientists—the general public and students have full access to it. Through the Global Drifter Program, classes can follow their own adopted buoy or any others in the fleet in near real-time. Students can retrieve and plot coordinates, time stamps, and Sea Surface Temperature (SST) to create their own time series or map their drifter’s journey over a day, a month, or even a full year.

map of GOES Sea Surface Temperature readings in the northern Atlantic Ocean on August 3, 2026 at 0655 GMT. we can see where cold water and warm water collide along a horizontal sweep easy of New Jersey. — Sea Surface Temperature: Image Credit – NOAA

This is why I have this opportunity to be part of this amazing study. It was suggested I personalize the buoys, so I reached out to a local print shop to see about getting Churchill High School stickers made, although I felt it was a long shot due to the short turnaround time. Luckily, QSL Printing saved the day, and all they wanted for compensation was a picture of the buoys covered with their stickers. I was so thankful for their help!

close up view of a drifting buoy, drogue folded; the surface float has been decorated with Teacher at Sea stickers, Churchill High stickers, an octopus, and the name ZOE — Drifter Zoe–decorated with an octopus and various NOAA & Churchill stickers

I named the buoys after my two sons and a family friend’s daughter: Otto, Nicolai, and Zoe, respectively. Shaun Dolk at NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) in Miami let me know that the best location to drop the drifters would be off the coast of Eureka, California. The ship’s chief scientist, Kevin Stierhoff, and I decided that deploying them every ½ hour would give some spacing between buoys, thereby decreasing the chance they would drift together.

We dropped Otto overboard first, and I realized it was a little odd dropping something named after my child into the ocean. He quickly bobbed away into the distance and I hoped that he would have a safe passage to wherever he might end up. Nicolai and Zoe met a similar fate soon after, although Zoe was greeted by whales that were traveling alongside the ship.

Drifter Deployment–Stacey (Teacher at Sea) & Melissa (marine biologist)

The expected/average lifetime of a drifter is around 450 days. Each drifter has a full identifier number, and the IMEI numbers are preprogrammed into each transmitter. The IMEI number is sent as a “signature” within each data message received. With nearly 1300 drifters transmitting every hour, it is essential to differentiate messages and separate them accordingly.

Should you happen to encounter one of these drifting buoys, you should reach out to the Global Drifter Program team with the details displayed on its surface float. In cases where the instrument is still functional and powered, they will coordinate its redeployment to continue its mission. While most of these instruments have a much shorter lifespan, the most resilient drifter ever documented managed to send back signals for an incredible 10 years, 4 months, and 21 days. It’ll be interesting to see how long my kiddos will be afloat!

a map of a drifter trajectory in the Pacific Ocean, showing a red line squiggling around the water west of California and then extending over to Japan — Longest drift ever! : Image credit–NOAA

When the drifters start transmitting, I will share a link with you all to see where they are out in the world!

Personal Log

Switching to working in the evening has been tiring, and it’s sometimes unclear what day it is. I now have pork chops for breakfast, and french toast for dinner which hasn’t been such a bad thing. We’re settling into our daily routine onboard. We haul up three trawls of fish every evening, as weather allows it. We’ve had great weather, and only a couple days of rougher seas. Speaking of which…have you ever used a treadmill on a ship? You don’t need to use the incline function, as you’ll be going up and down with the waves. You definitely need to hang on and it adds an extra work out element to your exercise routine.

Between trawls, the scientists have some downtime and we’ve learned how to felt sea creatures. Here are some examples of their creations:

a felted purple ray, hanging from the ceiling

a felted red crab with yellow spots, perched between some cables

Felted ray, crab, and jellyfish

Did you Know?

screenshot of sonar display on computer — sonar used to detect dolphin echolocation signals

Before we do any trawl for fish, we do a mammal watch 15 minutes before we put the net into the water. The net has a metal grate that is designed to keep any large creatures from entering, but it’s possible for dolphins or sea lions to get entangled in the mesh. We scan the water for any splashing, sounds, or spoutings. It’s difficult to discern in the dark, however.

This year, the science team has acquired infrared binoculars, which helps tremendously. You can see almost as well as daylight viewing, and I was able to see whales that were in the distance very easily. There is also a sonar that can show dolphin echolocation soundings, which also assists crew in checking if they are in the area. We had to cancel a trawl this past week due to dolphins hanging around the ship, even after we tried moving to another area. Last night, a sea lion followed us a bit, but we were able to do our trawl after it lost interest.

Pacific white-sided dolphins playing in our wake

July 31, 2026August 3, 2026

Cheyanne Vanderdonckt: The Survey Begins, July 30, 2026

NOAA Teacher at Sea

Cheyanne Vanderdonckt

Aboard NOAA Ship Oregon II

July 27 – August 12, 2026

Mission: Shark/Red Snapper Bottom Longline Survey, Leg 1

Geographic Area of Cruise: Western North Atlantic Ocean

Date: July 30, 2026

Latitude: 27° 40.261’ N

Longitude: 80° 12.372’ W

Weather Data from the Bridge: Southwest winds 15 to 20 knots. Seas 2 to 3 feet.

Science and Technology Log

I promised more details of how the longline survey is carried out and I will do my best to describe it here. A long fishing line (about a mile long) is equipped with weights and buoys at each end, along with a weight in the middle. The buoys also have a “high flyer,” which is a marker that sticks up off of the buoy so that we can see where it is. Attached to this longline are 100 shorter lines called “gangions” (say “GAN-jin”) with a number and a baited circle hook. (Circle hooks are used because they cause less damage to fish than “j-hooks.”) The longline is deployed, then given about an hour to “soak,” before we go back and start reeling it in.

illustration of a fishing vessel setting a long line. each end of the line is attached to an anchor and a buoy. along the line itself, shorter lines connected to fishing hooks are attached at regular intervals. this illustration depicts a fish on one of the hooks. — Longline setup (Credit: NOAA)

How do you manage a mile-long line with 100 shorter lines attached without getting everything tangled? It’s a careful and orderly — albeit fast-moving — operation. The hooks are set up in barrels with notches that keep them lined up and ready to be attached to the longline as it is let out off the stern (back of the ship). Later when the line is hauled in, somebody will place them back in order to be ready for the next station. When every element of this set-up — high flyers, weights, and every single hook — is either deployed (thrown off the stern) or hauled in at the bow (front of the ship), somebody is ready at the computer to record the exact time, latitude, longitude, the state of the bait, whether there is a fish, weather conditions, etc. for each hook. Fortunately, the computer records most of this automatically so there are only a few keys to push when each piece is either deployed or hauled in.

a white plastic barrel lined with baited hooks attached to short fishing lines — Hooks baited with mackerel attached to the gangions ready to be clamped to the longline

At our first station we caught four sandbar sharks (Carcharhinus plumbeus). When a shark is caught, it is a carefully coordinated operation to haul it up in a “cradle” (a big net with a stiff metal frame) using a crane. There is an operator working the crane, two people holding onto ropes attached to each side of the cradle, and at least two people to manage the shark’s head and tail while measurements and samples are taken. They are also communicating with the bridge where the officers driving the ship have to maneuver it to help get the cradle into position. The shark’s length is measured in millimeters and a small tissue sample is taken from its fin. Most sharks are also tagged, which allows scientists to track movements and examine growth rates. When smaller fish are caught, they are brought onto a measuring board in the middle of the deck. (More pictures and information about all of this will be coming in future posts!)

three people work to hold a large sandbar shark still against a cradle made of teal mesh webbing. we can see part of the face of the man in the foreground and only the arms of the other two scientists. everyone wears fish gloves. — William “Trey” Driggers helps secure the tail of a sandbar shark while it is tagged

Wildlife Spotted

One afternoon when the skies cleared after some rain, a pair of brown boobies (Sula leucogaster) came to rest on the weather station. A fellow science volunteer alerted me to their presence and we spent some time watching them spin around. To my amazement, they were still there hours later. I spent some more time watching them with the nearly full moon behind them.

two birds with brown backs and white undersides perch on either side of a weather vane. the sky is light blue and cloudy.

two birds are visible perched on either side of the weather vane, photographed at a distance. we can see the moon shining through the clouds and reflecting on the water.

Two brown boobies (Sula leucogaster) perched on the ship for hours

Simple Machines on a Ship

I have a student who got really interested in simple machines this year after, so I thought I would investigate as many of the simple machines as I could find on the ship. Simple machines are devices with few or no moving parts that make work easier. There are six basic types: wheel-and-axle, inclined plane, lever, pulley, wedge, and screw. A good example that we have at my school is a ramp, which is an inclined plane. I couldn’t carry a shopping cart full of science supplies up the stairs, but the ramp — along with the wheels and axles on the cart — allows me to push a heavy load up to the second floor relatively easily. Likewise, you probably can’t pick up your best friend, but if you get on a see-saw (a type of lever), you can send him high up into the air. Simple machines can be used on their own or in combination to make work easier.

There are many pulleys on the ship. They help make it easier to lift heavy objects. Winches are used to make it easier to haul in lines and to adjust the length of cables on cranes. Winches are essentially made of a wheel and axle and a lever. The rope or line wraps around the wheel as it turns on the axle. The handle acts as a lever that makes it easier to turn the wheel. The reel on a fishing rod acts as a winch when you turn the crank to reel the line in. Motorized winches use motors to turn the wheel.

view of pulleys clearly visible against a blue sky — Pulleys on one of the outriggers

view of the winch mounted on deck — Pulleys on one of the outriggers

A screw is a simple machine that is basically an inclined plane that wraps around a cylinder. If you have a screw at home, you can put your finger at the tip and follow that one groove all the way to the head. Think about cars driving up a circular ramp in a parking garage: they move on a continuous inclined plane that spirals around from bottom to top. The ship has engines that turn a big propeller and that propeller is a giant screw that pushes against the water to make the ship move forward. Although the blades of a propeller are separate rather than one continuous plane, they operate on the same basic principle as a screw.

Obviously I can’t see the ship’s propeller because it is under the water, but I asked the crew to tell me more about it. Oregon II has a variable pitch propeller which means that they can change the angle of the propellers relative to the axis that they spin around. The angle of this pitch changes the amount of work the screw can do with one full rotation. So a 1-foot pitch means that turning the screw one full rotation would theoretically move the ship 1 foot (This can vary depending on the other forces acting on the ship, such as currents and wind). Oregon II’s propeller has a maximum pitch of 6 feet. Naturally, I had to ask why you wouldn’t just always use the maximum pitch to go as fast as possible. It is like the gears on a bike or a car. If you have a bike with gears, you have probably found yourself pedaling furiously at some point, wearing yourself out without going any faster. If you choose the right gear, your energy will not be wasted. The officer driving the ship determines which pitch is appropriate for the conditions and the desired speed.

These are some of the simple machines I’ve discovered so far. Look around you and see what simple machines you have at home, work, school, or in the community. How do they make work easier? Can you use some objects in your house to make a simple machine?

Resources from NOAA:

NOAA has a great handout for students on the six basic simple machines at https://oceanexplorer.noaa.gov/wp-content/uploads/2025/04/simple-machines-handout.pdf (Teachers and parents: After introducing the basics of simple machines, look up some “Rube Goldberg” machine videos and challenge students to identify the different simple machines involved!)
Here is a lesson from NOAA that is designed for middle schoolers but which could easily be adapted for other levels in which students use basic materials to design a robotic arm using simple machines: https://oceanexplorer.noaa.gov/lesson/underwater-robots-simple-machines/

Personal Log

I am settling into life aboard ship. Because I get off duty at midnight and still need time to shower and wind down a bit, I am waking up later in the morning than I am used to in order to get a full night’s sleep. (I always tell my students how important sleep is and I like to practice what I preach.) This means that I wake up after breakfast and just about an hour before lunch is served. At home I tend to eat something on the sweet side for breakfast, but I am getting used to starting my day with a hearty meal of pulled pork, cod, or fried green tomato sandwiches. I was told to expect good food and I have not been disappointed. Everything is fresh and delicious! As you can imagine, the people aboard all have great stories and interesting backgrounds. I hope to introduce you to some of them in future posts.

As we had three days of transit time without much for me to do, I got to spend a lot of time just looking at the water and the sky and this is truly a gift. Everyone should have the opportunity to see and experience this. Earlier this summer I participated in a teacher training course with the Chesapeake Bay Foundation. I enrolled thinking it would be another way to enhance my scientific understanding of our local watershed and it certainly did that. However, the instructors and community partners also took the time to let us simply experience being in nature and encouraged us to let our students do the same. We visited an urban farm with a summer camp (and soon to have an all-outdoor year-round preschool program!) and the staff talked about how they incorporate nature to help students with emotional regulation and other skills that develop the whole child. They emphasized that these are things we can do anywhere outdoors. We don’t need to go off to the wilderness or even a park. In fact, the more we can get children to pay attention to the nature that they see everyday in their yard, neighborhood, or schoolyard, the deeper their connection will be. This will in turn drive their curiosity and their desire to learn more.

I am experiencing this myself aboard ship. Although I have work to do, taking some time to just experience what is around me with all of my senses helps to calm me, refresh me, and make me even more eager to keep learning. Being at sea is a new experience for me, but I can tell that even the veterans aboard still carry that sense of awe. People still come out to watch the sun set over the water and they still get excited to see dolphins surface. I wrote in a previous post about the teacher’s charge to help students feel emotionally secure so that they can learn. Finding ways to let them experience amazement at our world is another dimension to this. In first grade students learn about the phases of the moon and I always encourage my students to look for the moon throughout the night and day. It is notoriously hard to get a good picture of the moon with a cell phone, but I took this video before putting my phone away and just looking.

View of the moon from NOAA Ship Oregon II

Ship Rules

When I return to my classroom in August, I will spend a lot of time teaching my students about the rules of the school and the classroom. Of course, this is not always popular, but I do my best to explain the purpose of each rule and invite students to think about what could happen if we don’t follow it. (Admittedly, we sometimes get silly with these scenarios.) Children often feel bombarded by rules and that they are uniquely burdened by them. So I think it’s important to share examples of rules adults have to follow, as well. I’m going to have lots of great examples of rules Ms. Vanderdonckt had to follow while at sea. When you’re on land and close to the nearest hospital, your health and safety might be your own business. But on a ship far from shore, your health and safety affects everyone. If somebody were to be careless and get injured, it could jeopardize the entire mission that has been so carefully planned.

There are rules that are written and taught explicitly and then, of course, there are unspoken rules of etiquette and society that we just have to pick up on. This is something many neurodivergent students can struggle with. Special educators use tools like social stories to help them understand various social scenarios and explicitly teach expectations. Being in a completely different type of social environment is forcing me to simply ask people about etiquette and expectations. This is another dimension of my learning experience that I wasn’t even expecting. I knew I had a lot to learn about science and fishing, but I’m learning just as much by asking somebody, “Hey, if you’re working in your office with your door open does that mean it’s okay to ask a question?” Fortunately, people are very kind about teaching me the ropes.

Cheyanne, wearing a blue hard hat and an orange life vest, grins for a photo, hands in pockets. she is on the deck of NOAA Ship Oregon II. Behind her we see two other crewmembers with the CTD (conductivity, temperature, and depth probe). the sky is light blue and mostly cloudy. — Hardhats and PFDs (Personal Flotation Devices) are mandatory during operations. (Photo credit: Kleys Murillo)

Accessibility Corner

As a special educator, I’d like to share some insights and tips with teachers and caregivers that I am thinking about on my journey. As parents do shopping for the new school year, a big item on the list is new shoes. Many young students and/or students with fine motor challenges have difficulty tying shoes on their own. Velcro can be a great help but what if the pair your child is begging for have laces? My packing list suggested slip-on shoes because on a ship you need to get in and out of your shoes frequently and quickly. I don’t find most slip-ons comfortable so I’m using these elastic laces for my favorite sneakers. The bumps help me adjust them to my perfect comfort level. These could be great for students (or adults) who have trouble tying independently or who have sensory issues requiring fine tuning of laces. There are many brands, sizes and colors available.

close up view of two shoes with interesting, bumpy elastic laces. the shoes are on feet, which are propped up on something in the corner of the deck; we can see the railing and a bit of the water beyond. — My favorite pair of sneakers are easier to get on and off quickly with elastic shoelaces

Did You Know?

Sargassum is a type of floating brown algae. It can provide shelter and food to many types of marine life. It plays an important role in supporting life in the Atlantic Ocean but it can also cause issues when a lot of it washes up on shores at once. To learn more about sargassum, visit https://oceanservice.noaa.gov/news/sargassum/

clumps of sargassum floating in bright blue water, topped by bright blue sky with only a few hints of clouds — Sargassum floats on the surface of the water in the Atlantic Ocean

July 31, 2026July 31, 2026

Jo Slavitz: A Lot of Fish in the Sea: July 26, 2026

NOAA Teacher at Sea

Jo Slavitz

Aboard NOAA Ship Oscar Dyson

July 19 – August 10, 2026

Mission: Summer Pollock Acoustic Survey, Leg 3

Geographic Area of Cruise: Bering Sea, Alaska

Date: July 24, 2026

Weather Data from Bering Sea

Latitude: 58° 48.960’ N

Longitude: 173° 43.168′ W

Winds: E at 15-20 mph

Air Temperature: 45.68° F (7.6° C)

“The charm of fishing is that it is the pursuit of what is elusive but attainable, a perpetual series of occasions for hope.” – John Buchan

Science and Technology Log

As the saying goes “there are lots of other fish in the sea,” so how exactly does NOAA Ship Oscar Dyson find mostly Alaskan pollock in such a huge ocean? It’s a combination of structured transect planning, analyzing complex acoustic data and a little bit of luck.

Transects: At first glance the map of the 3 legs of the Alaskan Pollock Survey look like a crazy zig-zag path, so what’s going on and where are we going? The Oscar Dyson is traveling on a transect. A transect is a line drawn by scientists across an area used to measure, count and record the species living there. Oscar Dyson scientists are tasked with figuring out how many pollock are living in the Bering Sea, what age they are and their reproductive stage. As Oscar Dyson travels along each transect, the scientists decide where good places are to sample the pollock population using a long trawl net. It’s difficult to look into the ocean (though we will talk about cameras later) so NOAA scientists actually “listen” for the fish as they swim under the boat.

line drawing of NOAA Ship Oscar Dyson demonstrating acoustic calibration. we can see the sounding board extending beneath the hull; metal calibration balls are suspended farther beneath the sounding board. — The sounding board on the bottom of Oscar Dyson sends and receives frequency information. (NOAA Fisheries)

EchoSound: Many people are familiar with the way animals such as bats and dolphins emit sounds and use echoes to gather information about their surrounding environment. The scientists on the Oscar Dyson also use sound and echoes to gather information about their environment in the Bering Sea. The boat has a sounding board underneath called a transducer that emits energy pulses at different frequencies and receives the echoes as they are bounced back. Objects with different densities send back different amounts of echo energy. Scientists in the Acoustic Lab onboard Oscar Dyson watch a screen for echo patterns that match the patterns that are expected from individuals and schools of pollock.

photo of a screen displaying an echogram. in this graph, the x-axis is time and the y-axis is depth; colored dots represent the intensity of backscatter from a particular frequency encountered at each depth over time. — An echogram is a visualization of an echosound

Check out this image of an echogram. Echograms are a visualization of detected echo sounds. The bright red lines at the top and the bottom of the screen represent the surface and the dense ocean floor. The top wave of blues and greens is referred to as the “munge” ; it is a mixture of stirred up air bubbles, algae, plankton and other things that the team has determined is not pollock. Pollock are primarily in the area just above the bottom to about the middle of the water column. Boney fish such as pollock have a specialized organ called a swim bladder which allows them to take in and release gas, thus changing their density and allowing them to rise and fall in depth like a submarine. Not only is this organ useful to the fish, the air it contains has a different density from the surrounding water and reflects the echo energy that is emitted and picked back up by the ship’s transducer. Look carefully and you can see little colored dots and patches just above the ocean bottom depicted on the echogram. Those are fish and schools of fish. The scientists are confident that they are pollock but to be sure they need to collect a sample of the fish in those areas and get measurements from them.

diagram of a trawl net being pulled behind a vessel. labels point out the codend (the narrowest part at the back); the headline rope; the sweeps (lower lines); the weights attached to the lines; warp wires connecting the trawl to the vessel; and otterboards to help direct fish into the net. — Basic Trawl Net (source: Nettingland.com)

Trawl: Once a spot has been identified by the scientists, a call goes out to the crew, “Fishing, Fishing, Fishing”. This alerts all aboard that the vessel is going to break from the transect and drop the nets into the spots that had lit up with fish patterns on the echogram. The net is rolled out from a giant spool controlled by the deck crew rather than the scientists. The tip of the net is called the codend, from the old English word “cod” meaning a bag or pouch and this is where the fish are collected. At the opposite end of the net is the opening where fish enter. The weave, or meshes, of the net gets progressively tighter the closer it is to the codend.

three crewmembers wearing hard hats and life vests kneel to attach equipment to a portion of the trawl net on the deck of NOAA Ship Oscar Dyson — “Turtle” being attached to the kite

photo of the output from the FS70 echoscan showing a radar image across two-thirds of a circle — “Turtle” being attached to the kite

Attached to the net are several pieces of equipment that allow the scientist to analyze what is going into the net and when, during the trawl. The FS70, or netsounder, is a bright yellow device that also uses echoes to gather information. This piece is also sometimes called the “turtle.” You can see the crew here connecting it to a special part of the net called the kite. The kite and netsounder are attached and fly just above the opening of the net allowing the scientist to monitor what is going in.

Next to the picture of the crew you can see the image of what is being recorded by the netsounder on an information panel. This image of the “turtle” shows whether it is flying correctly, or oriented in the correct direction. The 2/3 circle image is a visualization of the echos the netsounder is receiving. The rainbow of color on the very bottom of this circle is the echo bouncing back from the bottom of the ocean, above that is another rainbow that represents the bottom of the net, above that if you look closely there are small blue marks just forming an oval with the rainbowed net bottom, those are the top of the net. When fish go into the net, they are represented as small dots, or blobs if a whole school is captured within this oval. The screen showing the echogram from below the ship and the screen with the netscan are placed next to each other on the control panel so that scientists can see the fish coming and hopefully adjust the nets accordingly to catch them.

close up view of a control panel showing two displays: the FS70 echoscan output, and the echogram of acoustic backscatter. — The control panel on the Bridge.

Scientists only want a sample of the fish, so they monitor the netsounder until they feel they have enough fish to accurately represent what they are seeing and then call “Haul Back.” This call tells the crew to raise the net back onto the boat, and the science crew to put on their wetlab gear in preparation for fish processing.

Try It on Dry Land

Swim bladders allow fish to change the density and buoyancy of their bodies, allowing them to change their position in the water column. Buoyancy is an upward force of an object causing it to float or sink. You can make a simple model of a fish’s swim bladder (and a fun catch game) using items found around your house.

You need:

Paperclips
1 pen cap (Bic pen or other with the stick part)
1 soda bottle with cap
Clay

Instructions:

illustration of a hand holding a plastic bottle filled with water and the pencap diver — Source: sciencebob.com

Fill bottle to top with water
Secure clay around stick of pen cap (do not cover opening)
Bend paperclip to form hook
Attach paperclip into clay with hook pointing down
Drop cap/hook into soda bottle so that it floats
Twist another paperclip into an L shape and drop to bottom
Put cap tightly on bottle

To Activate:

Squeeze the bottle and watch the pen cap drop
Release your grip and pen can will rise
Practice controlling where in the water column you can direct the cap
Can you dive the cap to the bottom and hook on to the L shaped paperclip?

What in the Science is going on… The cap holds a bubble of air underneath which allows it to float. When you squeeze the bottle the pressure makes the bubble smaller and changes the density of the cap causing it to sink. A fish’s swim bladder works by the same principles. Find out more here: www.instructables.com/Cartesian-Divers/

Personal Log

a circle, representing the earth tilted on its axis. arrows point out the north and south celestial poles, the meridian, the zenith (90 degrees). ellipses inside the circle represent three different paths of the sun. the first, closest to the north celestial pole, is labeled "Sun's path on July 21." The middle one, around the celestial equator, is labeled "Sun's path on March 21 and Sept 21." The third, closer to the south celestial pole, is labeled "Sun's path on Dec 21." — Sun Path Diagram

Life on Oscar Dyson is different in many ways then life on land. For one, the scientists work in shifts. There is a 4 am to 4 pm shift considered the dayshift and another from 4 pm to 4 am considered the nightshift. Acoustic monitoring and fishing happen all day and all night. I am on the day shift. Adding to the change in daily rhythms is the extended amount of daylight during the Alaskan summer season. The sun is up and bright when I hit my bunk to sleep. The sun will not set until approximately 12:30am, some nights I have gotten up in the night to watch the sunset out my window. I report to the Acoustic Lab at 4 am in the dark to find out what the night shift has been working on, the sun will then rise again at around 7 am. It takes some getting used to as the sun is a natural trigger for my body to know when to be active and when to rest. It makes for a long day, but who can complain with such a stunning beginning.

a beautiful view of sunrise over railing of the ship. there is a pile of rope in the foreground. the sky is golden, and the water, curling softly with the ship's wake, reflects the gold light. — Bering Sea Sunrise