Kathleen Harrison: …and Ending the Adventure, July 22, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
  July 4 — 22, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date:  July 22, 2011

Weather Data from the Bridge
True Wind Speed:  15.33 knots, True Wind Direction:  214.98°
Sea Temperature:  8.3° C, Air Temperature:  8.8° C
Air Pressure:  1014.59 mb
Overcast, 5 foot seas
Latitude:  55.54° N, Longitude:  155.57° W
Ship heading:  119°, Ship speed:  10.5 knots

Personal Log:  The time has come for me to pack my bright orange suitcase (thanks, Mom) and leave the NOAA ship Oscar Dyson.

my orange suitcase

Ok, so it is orange, at least I can find it in the luggage carousel at the airport.

The past 3 weeks have been an incredible adventure, and I am now making the journey home to Virginia Beach.  Almost everything I have seen and experienced has been new for me — especially identifying the animal species here in the Gulf of Alaska.  I am extremely grateful to the Teacher at Sea Program for allowing me to participate — I now have a better understanding of how real science is conducted, and am very excited to share this experience with my students, colleagues, family, and friends.

The title of this log entry might be Ending the Adventure, but I hope it is not the end of my relationship with NOAA.  I would like to be active in the Teacher at Sea Alumni group, and participate in other teacher activities that NOAA sponsors, such as Teacher in the Field, and Teacher in the Lab.  And, every time that I tell someone about this adventure, I will be reliving it all over again.

sunrise in Shelikof Strait

Sunrise in Shelikof Strait, 5:30 am.

In reflecting over the time that I have spent on board the ship, I have come to some conclusions about science, and life at sea:  1) Science is not easy, glamorous, or neat most of the time.  2) Science is messy, time-consuming, and frustrating most of the time.  3) Scientists must talk to each other, discussing ideas and problem solving.  4) Scientists on a team must at least get along with each other, and it is helpful if they actually like each other. 5) Scientists set very high goals, and then spend their time trying to make equipment work, manage millions of data points, and praying for good weather.  6)  The work that marine scientists do is vital to our understanding of the seas.  7)  Every science teacher should participate in real world research.  8) Alaska is a beautiful place.  9)  One can get used to the smell of fish.  10) I wonder what it will be like to walk on a non-moving surface again?

rain gear, the height of fashion

Rain gear pants, used to keep the fish slime off.

Mountains of the Alaskan peninsula

Snow covered peaks of the Alaskan Peninsula.

Thank you for reading this log, I hope that you have been informed and found it interesting.  The next time that you eat seafood, or see fish in an aquarium, think of the countless scientists, ship’s crew, and whales who have contributed their knowledge and skills to the conservation and use of the world’s oceans.

And thank you to my husband and daughters for letting me be away for 3 weeks.

Kathleen Harrison: City on the Sea, July 20, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
July 4 — 22, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date: July 12, 2011

Weather Data from the Bridge
True Wind Speed:  light (< 5 knots), True Wind direction:  variable
Sea Temperature:  9.75° C, Air Temperature:  10.38° C
Air Pressure:  1012.3 mb
Ship Heading:  297°, Ship Speed:  11.3 knots
Latitude:  56.45° N, Longitude:  155.04° W
Patchy fog, very calm seas

Science and Technology Log

The Oscar Dyson is like a self-contained city for 35 people that floats on the sea.  All of the engine fuel and oil, food and provisions for the NOAA staff, ship’s crew, and scientists have to be brought on board while the ship is in port.  On this leg of the Walleye Pollock Survey, the ship will be out to sea for 19 days.  This presents several issues that must be solved in order for the people to be comfortable, and for the research to be performed.

the water maker of the oscar dyson

This piece of machinery converts sea water into fresh water for the people on the Oscar Dyson. (courtesy of Anne Mortimer)

First, fresh water is needed, about 100 gallons per person, per day.  For 35 people, that is 3500 gallons per day.  The ship has a storage capacity of 9000 gallons.  Do the math, and you can see that a daily supply of fresh water is needed.  Well, the ship has 2 water makers that convert sea water into fresh water.  Basically, the water is heated, vacuum pumped, and evaporated, then collected in the fresh water storage.  Salt does not evaporate, so it is left behind.  The evaporator uses the sea water to power an ejector pump (that creates the vacuum) and keep the unit cool. The brine (super salty water) created from the evaporation is sent overboard by the ejector pump.

engineering room control panel

The engineer controls the power that the generators make with this panel. See the horizontal bar running the length of the panel - even the engineers need something to hold on to during rough seas. (courtesy of Anne Mortimer)

Next, electricity is needed to power the galley appliances, run the washers and dryers, lights, computers, ship’s bridge instruments, and a host of other things.  The ship has 4 generators that are capable of producing enough energy to not only power the propeller, but also the whole electrical need of the ship.  The control panels for each generator are used to divert some of the power to each part of the ship, so that I can charge my camera battery, use my computer, or turn on the light in my room.

generator number 2

This is generator number 2 on the Oscar Dyson. There are 4 generators, but only 2 are online at any one time. (courtesy of Anne Mortimer)

Another issue is the power needed to run the propeller.  For the 19 days the ship is out to sea, there are usually 2 generators running.  The ship’s computer decides which generators are needed for the speed that is required at any one time.  In heavy seas, or when more power is needed, a 3rd, or even the 4th generator will be brought on.  As generators are used, they wear and tear, so the computer determines what the most efficient use of them will be for each situation.  Everything can be manually controlled as well.  Every month or so, each generator needs an oil change.

price of fuel

The current price of diesel fuel in Kodiak, Alaska.

They hold about 65 gallons of oil!  The used oil is kept on board until the ship docks back in Kodiak.  Also, about every 20,000 hours, each generator needs to be overhauled.  This is done by a team of mechanics when the ship is in port, during the off season.  About 100,000 gallons of diesel fuel is stored at the beginning of the trip, and 2000 gallons are used each day.

Now, since the Oscar Dyson is a biological research ship, the usually noisy generators have been quieted, so that the fish are not scared away.  One way to quiet a very large, 1600 hp engine, is to put it on a rubber mat.  Another way is to send the energy from the generator through a large box, which then converts it to electrical energy, and that is transmitted to the propeller by thin wires.  This reduces the vibrations in the hull.

To be an engineer on a ship, a person usually would go to a marine academy and obtain a degree in marine engineering.  During school and shortly after, time spent as an intern is valuable to gain experience.  Once the new engineer is employed on a ship, he or she would start at the bottom of the team, maybe as 3rd engineer, depending on how large the ship is.  With experience, and management skills, the engineer could move up to 2nd, then 1st, then Chief engineer.  Of course, a ship’s engineer must love being at sea, and living on a ship.

Personal Log

We had a fabulous day for wildlife and scenery watching – bright sunshine (until 11:00 pm), calm seas, and close proximity to Kodiak Island.  I saw stunning rocky cliffs, Dall’s porpoises, and whales – probably Fin whales.  I was overwhelmed with the beauty and scale of Kodiak Island.

evening sun shine

I love the way that the sun glitters on the water. I took this photo about 7:00 in the evening.

kodiak cliffs

Rocky cliffs of Kodiak Island on a sunny day.

sunlight through the fog

The sun light is breaking through the clouds about 2 miles away.

Kathleen Harrison: CTD, XBT, Drop, July 18, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
July 4 — 22, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date: July 18, 2011

Weather Data from the Bridge
True Wind Speed:  19.35 knots, True Wind Direction:  231.44°
Sea Temperature:  10.5° C, Air Temperature:  10.11° C
Air Pressure:  1010.53 mb
Latitude:  57.54° N, Longitude:  154.37° W
Ship speed:  12.4 knots, Ship heading:  134.5°
Fog on the horizon, overcast

Science and Technology Log

One thing that I have learned on this trip (don’t worry, I have learned more than one thing) is that the government, and scientists, like to use abbreviations for equipment, procedures, and groups of people.  For example,  did you know that MACE stands for Midwater Assessment Conservation Engineering?   Well, now you do. The NOAA scientists that are aboard the Oscar Dyson work for the Alaska Fisheries Science Center, which is part of MACE.  Three of the abbreviations that I have become familiar with are:  CTD (conductivity, temperature and depth), XBT (expendable bathythermograph), and Drop (Drop camera).  These are devices or procedures that the NOAA scientists use on board the Oscar Dyson to gather information that will help in determining the biomass of Pollock.

Conductivity, Temperature and depth device

The CTD measures conductivity, temperature and depth of sea water.

When I say “the CTD”, I am referring to a device, but the letters actually come from the procedures that the device performs.  It is lowered into the water on a cable, and its instruments measure the conductivity (how much electricity will pass through – an indirect way of measuring salinity) and  temperature of the sea water, and depth.  Niskin bottles may be attached to the CTD frame to collect sea water at selected depths.  This information gives scientists knowledge about sea water properties, and over time, will indicate changes in the environment.

Watch this video to see the data as it is being collected.

launching the XBT

A hard hat and flotation device are required on the weather deck (any deck open to the weather), even to launch the XBT.

Launching the XBT has been one of my jobs on the Oscar Dyson, at least during my shift.  This device measures temperature and depth of sea water.  It is basically thrown overboard out of a handheld launcher, which looks like a giant pistol thing, and remains attached to a very thin wire.  Data is sent through this thin wire until it reaches the ocean floor, then the wire is broken.  The device is not retrieved – hence the name – expendable.


The data is graphed, and a beautiful thermocline is produced.  An XBT is launched 3 – 4 times a day, in different locations.

camera and light attached to frame

The Drop Camera is attached to a frame to protect it. The light is at the bottom of the frame.

The Drop Camera is an underwater camera that is lowered to the ocean floor.  The camera is pressure activated, so it starts recording at a certain depth.  It has a bright light that comes on when the camera is operating.  Extra line is fed out, because the ship is still moving, and the scientists do not want the camera to drag across the bottom.  It records for a few minutes, then it is hauled back to the boat, the memory card is retrieved, and the video is examined.  This information about the ocean floor is valuable to commercial fishermen, and future scientific missions.

sea stars and flat fish

The ocean floor close to Alaska's coast is home to a variety of sea stars, including brittle stars, as well as flat fish such as sole, flounder, and halibut. (NOAA Ocean Explorer)

New Species Seen  

Minke whale

Great Northern Diver (Loon)

Harbor Seal

Fin Whale

Humpback whale

4:30 am, Shelikof Strait

I was blessed to see this full moon about 4:30 am, with Mt. Douglas (elev. 7000 ft) in the background, in the Shelikof Strait.

Personal Log

Today was a fantastic day for wildlife and scenery viewing, as the sun was shining, the winds were calm, and it stays light until midnight here in the Shelikof Strait, west of Kodiak Island.  I started the day by going to the bridge around 4:30 am, and was delighted to see a bright full moon, and volcanoes of the Alaskan Peninsula.  The day only got better, as the sun rose around 5:30 am.

fin whale blow and dorsal fin

I have new respect for whale photographers, they are very hard to capture in a photo, here is my amateur attempt.

I spent a lot of time on the flying bridge, looking for whales, and finally took a photo of a spout and fin.  I was so excited!  You have to be looking at the right spot, at the right time.  Our transects take us close to Kodiak Island and its rocky cliffs, as well as the Alaskan Peninsula with its impressive glacier covered volcanoes.

bold and steep cliffs of Kodiak

The cliffs of Kodiak rise straight up out of the sea, bold and stunning.

We had a successful trawl today, and I spent several hours in the fish lab.  My head was kept warm by this pink knit hat that my sister made for me.  Thanks, Jan!

the fish lab is cold, need a hat

Thanks, Jan, for making this hat for me, I was nice and warm while processing fish today!

Kathleen Harrison: Finding Fish, July 12, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
July 4 — 22, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date: July 12, 2011

Weather Data from the Bridge
Air Temperature:  10.15° C, Sea Water Temperature:  7.6° C
True Wind Speed:  12.26 knots, True Wind Direction:  191.38°
Very foggy, visibility < 1/4 mile
Door open on bridge to hear other fog horns
Latitude:  56.07° N, Longitude:  158.08° W
Ship Heading:  24°, Ship Speed:  11.7 knots

Science and Technology Log:  Finding Fish

In a previous log, I talked about using nautical charts and trawling as 2 methods used in calculating the biomass of Walleye Pollock in the Gulf of Alaska.  Finding the fish to catch is tricky business in the ocean, they don’t usually come up to the surface and say hi.  The NOAA scientists working on the Walleye Pollock Survey spend a lot of time looking for fish, so that their trawling efforts won’t be wasted (that is the general idea, anyway).  How do you look for fish in the ocean?  With acoustics, of course, another method used in calculating biomass.

Acoustics is the use of sound, which will travel through the water, and bounce off of objects that it hits.  There is Simrad ER60 echosounder  that operates 5 transducers mounted on the center board under the ship, and it continuously sends out sound waves.

multibeam sonar mapping the ocean floor

The Simrad ER60 echosounder sends sound directly under the ship, finding fish anywhere in the water column.

In the Acoustics Lab of the Oscar Dyson, the data from the multi-beam echosounder is being studied all of the time.  The sound waves leave the device, travel down, hit the swim bladder in a fish (the fish doesn’t even know), and reflect back to the ship.  The time it takes for the sound to return is used to calculate the distance down, and a computer generated picture called an echogram is produced.

echogram shows surface, fish, and bottom

The echogram shows plankton at the surface in blue/green, fish near the bottom as red/brown spots, and the ocean floor as a red/brown line.

The echogram tells the scientists several things.  The surface of the water is shown, with surface dwelling organisms such as krill, phytoplankton, zooplankton, and juvenile fish.  The fish that are mid-water are shown as well, showing up as red or blue dashes or blobs.  This is where the Pollock usually are.  Some fish are bottom feeders, and the red and blue dashes on the bottom represent those.  The ocean floor is also shown, which is very important when choosing which type of trawl to use.   If the bottom is flat, the Poly Nor’Easter could be used to capture to fish on the bottom.  The Aleutian Wing Trawl might be used in mid water if the bottom is rocky and irregular.

Now, looking at the fish from the surface is nice, but wouldn’t it be better to see them close up?  Of course!  The scientists have another tool at their disposal, and no, it isn’t me diving down to the fish (brrr).  This tool is called a Drop Target Strength, or DTS.

echosounder can be dropped into water

The Drop Target Strength (DTS) can be lowered into the water, and get closer to the fish. The information is fed into the computer by a water proof cable.

About once a day, or every other day, the DTS is lowered over the side, and it starts sending out sound waves (3 pings/second), just like the echosounder mounted on the ship.  The advantage with the DTS, though, is that it is closer to the fish, giving a more detailed and accurate picture.  Individual fish can be sighted.  Taking a picture of a fish is kind of like taking a picture of a toddler, they don’t hold still very well.  So, a count of the fish on the echogram might not be exact.  Also, they might change the angle of their body, making the sound wave reflect off their swim bladder at a different angle.  The colors on the echogram are significant:  brown and red mean a strong signal, yellow is medium, and green and blue indicate a weak signal.

echogram shows individual fish

Studying the echogram from the DTS gives scientists a better picture of where the fish are. Each individual wavy line is probably a separate fish.

The scientists will study the echograms to determine where the fish are, and make a decision to fish or not.  Once fishing begins, they will move from the acoustics lab to the bridge, and study the echograms there.  An estimate of how many fish are in the net is made, and then the scientists will ask the crew to “haul back” the net.   (I am learning a whole new language!)  Then, things get very busy as we head to the fish lab to process the fish.

scientists at their desks in the acoustics lab

Here are the NOAA scientists that I am privileged to work with on the Oscar Dyson: (left to right) Darin Jones, Fish Biologist, Denise McKelvey, Fish Biologist, Neal Williamson, Chief Scientist.

New species seen:

Giant Pacific Octopus (juvenile, 1 cm)

Opalescent Squid

Chinook (King) Salmon

Egg yolk jelly fish

Sculpin (juvenile)

North Pacific sea nettle

Spud sponge

tiny squid, only 2 cm long

These are juvenile squid, about 2 cm long. They are nearly transparent.

giant pacific octopus, juvenile, only 1 cm

This is a juvenile Giant Pacific Octopus, only 1 cm wide, complete with 2 huge eyes, and 8 perfect legs.

Personal Log

My days have developed a routine now:  wake at 3:30 am (ugh), start my shift in the acoustics lab about 4:00, breakfast at 7:30, lunch at 11:30, end my shift at 4:00 pm, dinner at 5:30, shower, in bed by 8:00.

my window and life boats

See the orange life saving ring? My window is just to the right of the ring. The 3 white canisters on the back wall hold life rafts that inflate upon release of the canister.

In between these times, I work on my Teacher at Sea log, post pictures on Facebook, read and answer e-mail, visit the bridge and ask lots of questions, and of course, process fish whenever there is a trawl (very fun).  Today marks the halfway point of our cruise!  The ship is quieter than I thought, even though there are 35 people on board, the most that I ever see might be 10 during mealtimes.  There is constant background noise of the ship’s engines, waves hitting the bow of the ship, creaks and groans of the furniture as the ship rolls, but I am used to it now, and hardly notice it.  I am thankful for the calm weather that we have had so far.

Kathleen Harrison: Fish Stick, Anyone? July 15, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
July 4 — 22, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date: July 15, 2011

Weather Data from the Bridge
True Wind Speed:  34 knots, True Wind Direction:  284.43
Sea Temperature:  10.02° C, Air Temperature:  11.34° C
Air Pressure:  1014.97 mb
Latitude:  56.12° N, Longitude:  152.51° W
Sunny, Clear, Windy, 10 foot swells
Ship speed:  10 knots, Ship heading:  60°

Science and Technology Log

The Walleye Pollock is an important economic species for the state of Alaska.  It is the fish used in fish sticks, fish patties, and other processed fish products.  Every year, 1 million tons of Pollock  are processed in Alaska, making it the largest fishery in the United States by volume.  The gear used to catch Pollock is a mid-water trawl, which does not harm the ocean floor, and hauls are mostly Pollock, so there is very little bycatch.

table full of pollock

A sample of pollock that the Oscar Dyson caught for scientific study. A "drop" in a very large "ocean" of pollock industry.

Although Pollock fishermen would like to make as much money as they can, they have to follow fishing regulations, called quotas, that are set each year by the North Pacific Fishery Management Council (NPFMC).  The quotas tell the fishermen how many tons of pollock they can catch and sell, as well as the fish size, location, and season.  The NOAA scientists on board NOAA Ship Oscar Dyson have an important role to play in helping the NPFMC determine what the quotas are, based on the biomass they calculate.

The quotas are set in order to prevent overfishing.  Pollock reproduce and grow quickly, which makes them a little easier to manage.  When fishing is uncontrolled, the number of fish becomes too low, and the population can’t sustain itself.  Imagine being the lone human in the United States, and you are trying to find another human, located in Europe, only you don’t know if he is there, and all you have is your voice for communication, and your feet for traveling.  This is what happens when fish numbers are very low– it is hard for them to find each other.

There are many situations where uncontrolled fishing has cost the fishermen their livelihood. For example, in the early 1900s, the Peruvian Anchovy was big business in the Southeast Pacific Ocean.  Over 100 canneries were built, and hundreds of people  were employed.

anchovy catch graph

This graph shows how the Peruvian Anchovy catch rose to record heights in 1970, then collapsed in 1972. This could have been prevented by effective fishery management.

Scientists warned the fishermen in the 1960s that if they didn’t slow down, the anchovies would soon be gone.  The industry was slow to catch on, and the anchovy industry crashed in 1972.  The canneries closed, and many people lost their jobs.  This was an important lesson to commercial fishermen everywhere.

The Walleye Pollock (Theragra chalchogramm) is a handsome fish, about 2 feet long, and greyish – brown.  Most fishermen consider him the “dog” food of fish, since he pales in comparison to the mighty (and tasty) salmon.  Nonetheless, Pollock are plentiful, easy to catch, and thousands of children the world over love their fish sticks.

Besides calculating biomass, there are 2 other studies going on with the Pollock and other fish in the catch.  Scientists back at the Alaska Fisheries Science Center (AFSC) in Seattle are interested in how old the fish are, and this can be determined by examining the otoliths.

2 pollock otoliths

Here are 2 otoliths from a pollock. The one on the left shows the convex surface, the other shows the concave surface.

These are 2 bones in the head of a fish that help with hearing, as well as balance.  Fish otoliths are enlarged each year with a new layer of calcium carbonate and gelatinous matrix, called annuli, and counting the annuli tells the scientists the age of the fish.  Not only that, with sophisticated chemical techniques, migration pathways can be determined.  Amazing, right?  The otoliths are removed from the fish, and placed in a vial with preservative.  The scientists in Seattle eagerly await the return of the Oscar Dyson, so that they can examine the new set of otoliths.  By keeping track of the age of the fish, the scientists can see if the population has a healthy distribution of different ages, and are reproducing at a sustainable rate.

Another ongoing study concerning the Pollock, and any other species of fish that are caught during the Pollock Survey, deals with what the fish eat.

stomach being put into a bag for later study

A pollock stomach is put into a fabric bag, which will be placed in preservative. Scientists at the Alaska Fisheries Science Center will study the contents to determine what the fish had for lunch.

Stomachs are removed from a random group of fish, and placed into fabric bags with an ID tag.  These are placed into preservative, and taken to Seattle.  There, scientists will examine the stomach contents, and determine what the fish had for lunch.

Personal Log  

I learned about fishing boundaries, or territorial seas, today.  In the United States, there is a 12-mile boundary from the shore marked on nautical charts.  Inside this boundary, the state determines what the rules about fishing are.  How many of each species can be kept, what months of the year fishing can occur, and what size fish has to be thrown back.   Foreign ships are allowed innocent passage through the territorial seas, but they are not allowed to fish or look for resources.  Outside of that is the Economic Exclusion Zone (EEZ) which is 200 miles off shore.  The EEZ exists world-wide, with the understanding among all international ships, that permits are required for traveling or fishing through an EEZ that does not belong to the ship’s native country.

Everyone was tired at the end of the day, just walking across the deck requires a lot more energy when there are 10-foot swells.  Check out this video for the rolling and pitching of the ship today.

Kathleen Harrison: Shumagin Islands, July 9, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
July 4 — 22, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date: July 9, 2011

Weather Data from the Bridge
True wind direction:  59.9°, True wind speed:  11.44 knots
Sea Temperature:  9°C
Air Temperature:  8.9°C
Air pressure:  1009.74 mb
Foggy with 1 mile visibility
Ship heading:  88°, ship speed:  11 knots

Science and Technology Log

The Shumagin Islands are a group of about 20 islands in the Gulf of Alaska, southwest of Kodiak Island.  They were named for Nikita Shumagin, a sailor on Vitus Bering’s Arctic voyage in 1741.  They are volcanic in origin, composed mostly of basalt.

Shumagin Islands

Bold and mountainous, the Shumagin Islands rise from the sea in the Gulf of Alaska.

Several islands even exhibit hexagonal basaltic columns.  There are about 1000 people who reside in the islands, mostly in the town of Sand Point, on Popof Island.  According to the United States Coast Pilot (a book published by NOAA with extensive descriptions about coastlines for ship navigation), the islands extend out 60 miles from the Alaskan Peninsula.  They are bold and mountainous.

hexagonal basalt

When this island formed, volcanic lava cooled into basalt hexagonal columns.

The shores are broken in many places by inlets that afford good anchorages.  The shores are rockbound close to.  Fishing stations and camps are scattered throughout the group, and good fishing banks are off the islands.  Fox and cattle raising are carried on to some extent.

long range view of SI, Alaskan Peninsula

Shumigan Islands to the left, snow covered peaks of Alaskan Peninsula in background. An amazing sight on a rare sunny day in the Gulf of Alaska.

Sea water quality is very important to the scientists on the Oscar Dyson.  So important, that it is monitored 24 hours a day.  This is called the Underway System.  The sea water comes through an intake valve on the keel of the bow, and is pumped up and aft to the chem lab.  There, it goes through 4 instruments:  the fluorometer, the dissolved Oxygen unit, the Thermosalinograph (TSG), and the ISUS (nitrate concentration).

The fluorometer measures the amount of chlorophyll and turbidity in the sea water once every second.  A light is passed through the water, and a sensor measures how much fluorescence (reflected light) the water has. The amount of chlorophyll is then calculated.  The measurement was 6.97 µg/L when I observed the instrument.  The amount of  phytoplankton in the water can be interpreted from the amount of chlorophyll.  Another sensor measures how much light passes through the water, which gives an indication of turbidity.  Twice a day, a sample of water is filtered, and the chlorophyll is removed.  The filter with the chlorophyll is preserved and sent to one of the NOAA labs on land for examination.

chem lab

Here are all of the water quality instruments, they are mounted to the wall in the chem lab. Each one has a separate line of sea water.

The next instrument that the water passes through will measure the amount of dissolved oxygen every 20 seconds.  Oxygen is important, because aquatic organisms take in oxygen for cellular respiration.  From plankton to white sharks, the method of underwater “breathing” varies, but the result is the same – oxygen into the body.  The oxygen in the water is produced by aquatic plants and phytoplankton as they do photosynthesis, and the amount directly affects how much aquatic life can be supported.

The TSG will measure temperature, and conductivity (how much electricity passes through) every second, and from these 2 measurements, salinity (how much salt is in the water) can be calculated.  The day that I observed the TSG temperature was 8.0°  C, and the salinity was 31.85 psu (practical salinity units).  Average sea water salinity is 35.  The intense study of melting sea ice and glaciers involves sea water temperature measurements all over the world.  A global data set can be accumulated and examined in order to understand changing temperature patterns.

instrument to measure

This instrument measures the amount of nitrate in the sea water. It is called the ISUS.

The last instrument measures nitrate concentration in the sea water every couple of minutes.  It is called ISUS, which stands for In Situ Ultraviolet Spectrophotometer.  Nitrate comes from organic waste material, and tends to be low at the surface, since the wastes normally sink to the bottom.  The normal value is .05 mg/L, at the surface, at 8°C.  Values within the range of 0.00 to 25 mg/L are acceptable, although anything above 5 is reason for concern.

All of the data from these instruments is fed into a ship’s computer, and displayed as a graph on a monitor.  The Survey Technician monitors the data, and the instruments, to make sure everything is working properly.

New Species Seen today:

Whale (unknown, but probably grey or humpback)

Horned Puffin

Dall’s Porpoise


Chum Salmon


monitor shows current data

The current water quality data is shown on this computer screen beside the instruments.

Personal Log

Living on a ship is quite different from living at home.  For one thing, every item on the ship is bolted, strapped, taped, or hooked to the bulkhead (wall), or deck (floor).  Most hatches (doors) have a hook behind them to keep them open(this reminds me of when I put hooks behind my doors at home to keep little children from slamming them and crushing fingers).  Some hatches (around ladderways (stairwells)) are magnetically controlled, and stay open most of the time.  They close automatically when there is a fire or abandon ship situation or drill.  Every drawer and cabinet door clicks shut and requires moving a latch or lever to open it.  For some cabinet doors that you want to stay open while you are working in the cabinet, there is a hook from the bulkhead to keep it open.

bracket holds copier

The copier machine is held in place by a 4 post bracket that is bolted to the floor.

On every desk is a cup holder, wider on the bottom than the top, designed to hold a regular glass or a cup of coffee.  If one of those is not handy, a roll of duct tape works well for a regular glass.  All shelves and counters have a lip on the front, and book shelves have an extra bar to hold the books in.  Trash cans and boxes are lashed to the bulkhead with an adjustable strap, and even the new copier machine has a special brace that is bolted to the deck to hold it in one place (I heard that the old copier fell over one time when there was a particularly huge wave).  There are lots of great pictures on the bulkheads of the Oscar Dyson, and each one is fastened to the bulkhead with at least 4 screws, or velcro.  There are hand rails everywhere – on the bulkhead in the passageway (hallway) (reminds me of Mom’s nursing home), and on the consoles of the bridge.

hallway hand rails

This view down the hall shows the hand rail. It comes in handy during rough weather.

Desk chairs can be secured by a bungee cord, and the chairs in the mess (dining room)  can be hooked to the deck.

Another thing that is different from home is the fact that the Oscar Dyson operates 24-7 (well, in my home, there could easily be someone awake any hour of the night, but the only thing they might operate is the TV). The lights in the passageways and mess are always on.  The acoustics and water quality equipment are always collecting data.  Different people work different shifts, so during any one hour, there is usually someone asleep.  Most staterooms have 2 people, and they will probably be on opposite shifts.  One might work 4 am to 4 pm, and the other would work 4 pm to 4 am.  That way, only one person is in the room at a time (there is not really room for more than one).  There is always someone on the bridge – at least the Officer of the Deck (OOD) – to monitor and steer the ship.  During the day, there is usually a look out as well.

binoculars on the bridge

These binoculars are used by the look out to scan the surrounding area for anything in the water - whales, boats, islands, kelp, or anything else in proximity to the ship.

His job is to, well, look out – look for floating items in the water, whales, rocks, and other ships (called contacts or targets).  This helps the OOD, because he or she can’t always keep their eyes on the horizon.

I have thoroughly enjoyed living on the Oscar Dyson (we have had calm seas so far), and talking with the NOAA staff and crew.  They are ordinary people, who have chosen an extraordinary life – aboard a ship.  It has challenges, but also great rewards – seeing the land from a different perspective, being up close to sea life, and forging close relationships with shipmates, as well as participating in the science that helps us understand the world’s oceans.

Kathleen Harrison: First Trawl, July 7, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
  July 6– 17, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date: July 7, 2011

Weather Data from the Bridge
True Wind Speed:  18.7 knots
True Wind direction:  145.55°
Sea Temperature:  8.12° C
Air Temperature:  9.65° C
Air Pressure:  1013.2 mb
Ship’s Heading:  299°, Ship’s Speed:  11.8 knots
Latitude:  54.59°N, Longitude:  145.55°W

Science and Technology Log
The primary mission of the Oscar Dyson Walleye Pollock Survey is to estimate the biomass (mass of the living fish) of the Pollock in the Gulf of Alaska.  Read about why Pollock are important here:  Pollock    Now, you can’t exactly go swimming through the Gulf of Alaska (brrrr) and weigh all of the fish, so the NOAA scientists on board use indirect methods of measuring the fish to come up with an estimate (a very accurate estimate).  Two of these methods include using nautical charts, and trawling.

Nautical charts are used for navigation, and location.  The Oscar Dyson has several systems of charts, including electronic and paper.  Each chart contains latitude, longitude, and ocean depth, as well as lands masses and islands.  A chart that shows ocean depth is called a bathymetric chart.

bathymetric map

Here is a bathymetric map for part of the Gulf of Alaska. The change in color from green to blue shows the edge of the continental shelf.

These need updating continually, because the sea floor may change due to volcanic eruption or earthquakes.  The Officer of the Deck (OOD, responsible for conning and navigating the ship) needs to know how deep the ship sits in the water, and study the bathymetric charts, so that the ship does not go into shallow water and run aground.  The lines on the bathymetric chart are called contour lines, depth is shown by the numbers on the lines.  Sometimes every line will have a number, sometimes every 5th line will have a number.   A steep slope is indicated by lines that are close together, a flat area would have lines that are very far apart.  The OOD also need to know where seamounts (underwater volcanoes) and trenches (very deep cracks in the ocean floor) are because these may affect local currents.  GPS receivers are great technology for location, but just in case the units fail, and the ship’s technology specialist is sick, the OOD needs to know how to use a paper chart.  He or she would calculate the ship’s position based on ship’s speed, wind speed, known surface currents, visible land masses, and maybe even use star positions.  Here in Alaska, star position is helpful in the winter, but not in summer.  (Do any of my readers know why?)

The Oscar Dyson’s charted course follows a series of parallel straight lines around the coast of Kodiak Island, and other Aleutian Islands.  These are called transects, and allows the scientists to collect data over a representative piece of the area, because no one has the money to pay for mapping and fishing every square inch.

The Chief Scientist on the Oscar Dyson is always checking our location on the electronic chart at his desk.  It looks something like this:

map of transects, Gulf of Alaska

This chart shows some of the transects for the Oscar Dyson in the Gulf of Alaska.

Several things are indicated on this chart with different symbols:  the transect lines that the ship is traveling (the straight, parallel lines), where the ship has fished (green fish), where an instrument was dropped into the water to measure temperature and salinity (yellow stars), and various other ship activities.  It also shows the ocean depth.  This electronic version is great because the scientists can use the computer to examine a small area in more detail, or look at the whole journey on one screen.

They can also put predicted activities on the map, and then record actual activities.  The scientists also use several systems for the same thing;  recording the ship’s path and activities in the computer, as well as making notes by hand in a notebook.

When the scientists want to catch fish, they ask the crew to put a trawling net into the water.  The basic design of the trawl is a huge net attached to 2 massive doors.

otter trawl

This is the basic design for a trawl net, showing the doors that hold the net open, and the pointed end, where the fish are guided, called the cod end.

The doors hold the net open, as it is dragged behind the boat.  There are 2 different trawling nets aboard the Oscar Dyson:  one that trawls on the bottom called the PNE (Poly Nor’Easter), and one that trawls midway in the water column called the AWT (Aleutian Wing Trawl).  Another net called the METHOT can be used to collect plankton and small fish that are less than 1 year old.  The scientists determine the preferred depth of the net based on the location of fish in the water column; the OOD gets the net to this requested depth and keeps it there by adjusting the ship’s speed and the amount of trawl warp (wire attached to the net).
A trawl typically lasts 15 – 20 minutes, depending on how many fish the scientists estimate are in the water at that point (more about this later).  Today, a bottom trawl was performed, and 2 tons of fish were caught!  The net itself weighs 600 pounds, and is handled by a large crane on the deck at the stern (back) of the ship.  Operating the trawl requires about 6 people, 3 on the deck, and 3 on the bridge at the controls.  When the scientists judge that there are the right amount of fish in the net, it is hauled back onto the deck, weighed, and is emptied into a large table.

poly nor'easter

Here is the PNE being weighed with the cod end full of fish.

Then the scientists (and me) go to work:  sorting the fish by species into baskets, counting the fish, and measuring the length of some of them.  NOAA technology specialists have designed a unique data collection system, complete with touch screens.  A fish is placed on a measuring board, and the length is marked by a  magnetic stylus that is worn on the finger.  The length is automatically recorded by the computer, and displayed on a screen beside the board.  I measured the length of about 50 Atka Mackerel after the first trawl.

using the measuring board

In the fish lab, this mackerel is having his length measured. The data goes directly into the computer, and shows up on the screen in front of me.

By sampling the fish that come up in the trawl net, the scientists can estimate the size of the population.  Using the length, and gender distribution, they can calculate the biomass.

Personal Log
Some great things about living on the Oscar Dyson:  the friendly and helpful people, the awesome food, the view from the bridge.

Some challenging things about living on the Oscar Dyson:  taking a shower, putting on mascara, staying in bed while the ship rolls.

I started my 12-hour shifts, working from 4 am to 4 pm.  Well, maybe working is not the right word, I actually worked about 3 hours, and asked a lot of questions during my first shift.  The scientists are very patient, and explain everything very well.  We did one trawl today, and it was a good one.  I enjoyed sorting and counting the fish, and then measuring the length of them.  I will probably take a shower, eat dinner, and read for a short time before climbing into bed.  I have the top bunk, and it is plenty of room, except I can’t sit up straight.  Here is a picture of the stateroom.  After my shift, I will probably take a shower, eat dinner, watch a movie and fall asleep around 8:30.

view of my room

Standing at the door, this is the view into my stateroom. The bunks are on the right, the desk and closets are on the left. There is a tiny bathroom, as well as a small refrigerator.

The weather today has been windy, so there are 6 – 8 foot swells, and the ship is rolling a bit.  I have not been seasick yet – yippee!  The wind is supposed to calm down tomorrow, so hopefully we will have a smoother ride tomorrow night.

I learned the difference between pitch, roll, and heave:  pitch is the rocking motion of the ship from bow to stern (front to back), roll is the motion from side to side, and heave is the motion up and down.  The Oscar Dyson is never still, demonstrating all 3 motions, in no particular pattern.  Imagine standing in a giant rocking chair, and someone else (that you can’t see) is pushing it.

Here is a view from the bridge:

from the aft deck

View from the deck in front of the bridge, showing a gyrorepeater (the white column on the right), and a windbird (anemometer and wind vane) on top of the forward mast. You can also see a horizontal black bar in the center of the picture - that is the provisions crane.

Species seen today:
Northern Rockfish
Dusky Rockfish
Walleye Pollock
Pacific Ocean Perch
Kelp Greenling
Atka Mackerel
Pacific Cod
Fanellia compresson (octocoral)
Sea Urchin