Leah Johnson – NOAA Teacher at Sea Blog

August 2, 2015August 21, 2021

Leah Johnson: Fish Identification & Pisces Farewell, August 1, 2015

NOAA Teacher at Sea
Leah Johnson
Aboard NOAA Ship Pisces
July 21 – August 3, 2015

Mission: Southeast Fishery – Independent Survey
Geographical Area of Cruise: Atlantic Ocean, Southeastern U.S. Coast
Date: Saturday, August 1, 2015

Weather Data from the Bridge:
Time 12:13 PM
Latitude 033.995650
Longitude -077.348710
Water Temperature 24.37 °C
Salinity 36.179 ppt
Air Temperature 27.4 °C
Relative Humidity 83 %
Wind Speed 15.95 knots
Wind Direction 189.45 degrees
Air Pressure 1012.3 mbar

Science and Technology Log:
I am still amazed at the wealth of data collected aboard the Pisces on this survey cruise. I am getting better at identifying the fish as they are hauled up in the traps, as well as when I see these fish on video. Because of light attenuation, many fish look very different in color when they are underwater. Light attenuation refers to the gradual loss of visible light that can penetrate water with increasing depth. Red light has the longest wavelength on the visible light spectrum, and violet has the shortest wavelength. In water, light with the shortest wavelength is absorbed first. Therefore, with increasing depth, red light is absorbed, followed by orange, then yellow. Fish that appear red in color at the surface will not appear red when they are several meters below the sea surface where they are captured on camera.

For example, we hauled in some blackfin snapper earlier this week. At the surface, its color is a distinct red like many other types of snappers, and it has a black spot near the base of its pectoral fin. When I looked at the videos from the trap site, I did not realize that all of the fish swimming around with yellow-looking tails were the very same blackfin snappers that appeared in the traps! When I remembered that red light is quickly absorbed in ocean water and noticed the black spot on the pectoral fin and shape of the dorsal fin, it made more sense.

Top: Blackfin snapper collected from trap.
Bottom: Video still of blackfin snappers swimming near trap.

I tell my geology students every year that when identifying minerals, color is the least reliable property. I realize now that this can also apply to fish identification. Therefore, I am trying to pay closer attention to the shape of the different fins, slope of the head, and relative proportions of different features. The adult scamp grouper, for example, has a distinct, unevenly serrated caudal fin (tail) with tips that extend beyond the fin membrane. The tip of the anal fin is elongated as well.

Scamp grouper

Another tricky aspect of fish identification is that some fish change color and pattern over time. Some groups of fish, like wrasses, parrotfish, and grouper, exhibit sequential hermaphroditism. This means that these fish change sex at some point in their lifespan. These fish are associated with different colors and patterns as they progress through the juvenile phase, the initial phase, and finally the terminal phase. Some fish exhibit fleeting changes in appearance that can be caught on camera. This could be as subtle as a slight darkening of the face.

The slight shape variations among groupers can also lead groups of scientists to gather around the computer screen and debate which species it is. If the trap lands in an area where there are some rocky outcrops, a fish may be partially concealed, adding another challenge to the identification process. This is no easy task! Yet, everyone on board is excited about the videos, and we make a point to call others over when something different pops up on the screen.

We were all impressed by this large Warsaw grouper, which is not a common sight.

I have seen many more types of fish and invertebrates come up in the traps over the past week. Here are a few new specimens that were not featured in my last “fish” post:

Did You Know?

Fish eyes are very similar to those of terrestrial vertebrates, but their lenses that are more spherical.

lens from fish eye

Lens from fish eye

Personal Log:

I love being surrounded by people who are enthusiastic about and dedicated to what they do. Everyone makes an extra effort to show me things that they think I will be interested to see – which I am, of course! If an interesting fish is pulled up in the trap and I have stepped out of the wet lab, someone will grab my camera and take a picture for me. I continue to be touched by everyone’s thoughtfulness, and willingness to let me try something new, even if I slow down the process.

Me, on the deck of the ship. We just deployed the traps off the stern.

As our cruise comes to an end, I want to thank everyone on board for letting me share their work and living space for two weeks. To the NOAA Corps officers, scientists, technicians, engineers, deckhands, and stewards, thank you for everything you do. The data collection that takes place on NOAA fishery survey cruises is critical for the management and protection of our marine resources. I am grateful that the Teacher at Sea program allowed me this experience of a lifetime. Finally, thank you, readers! I sincerely appreciate your continued support. I am excited to share more of what I have learned when I am back on land and in the classroom. Farewell, Pisces!

July 31, 2015August 21, 2021

Leah Johnson: Career Spotlight: NOAA Corps Officer, July 30, 2015

NOAA Teacher at Sea
Leah Johnson
Aboard NOAA Ship Pisces
July 21 – August 3, 2015

Mission: Southeast Fishery – Independent Survey
Geographical Area of Cruise: Atlantic Ocean, Southeastern U.S. Coast
Date: Thursday, July 30th, 2015

Weather Data from the Bridge:
Time 12:13 PM
Latitude 34.18282
Longitude -76.13712
Water Temperature 25.62 °C
Salinity 35.3592 ppt
Air Temperature 29.8 °C
Relative Humidity 71 %
Wind Speed 13.23 knots
Wind Direction 159.25
Air Pressure 1013.2 mbar

Science and Technology Log:
Career Spotlight: I would like to introduce everyone to Ensign Hollis Johnson, one of the Junior Officers on NOAA Ship Pisces. She was kind enough to let me ask her a few questions about life at sea.

Ensign Hollis Johnson

Q: What is the role of a Junior Officer (JO) on this ship?

A: The primary duty of a JO is driving the ship. We are also the eyes and ears of the Commanding Officer (CO). We carry out standing orders, ensure ship safety, and also make sure the scientists are getting what they need for their survey work.

Q: Does this job description vary depending on the ship?

A: This is a generic fleet-wide description, and some ships are a little different. On hydrographic ships, there is more computer-based work with data collection. On fisheries ships, collateral duties are split amongst the JOs; for example, we have an environmental compliance officer, a safety officer, a movie officer, and a navigation officer.

Q: What do you like best about your job and being at sea?

A: I really like driving the ship. Few jobs offer this kind of an opportunity! I also like the fact that no two days are ever the same, so my job is a constant adventure. The best things about being at sea in general are the sunrises and sunsets, and the dolphins, of course.

Q: What do you find to be the most challenging aspect of your job and life at sea?

A: This job requires long hours. We can easily work 12-16 hour days, and while in port we still have to work some weekends. Because of this time commitment, we have to make sacrifices. But, we get that time back with our land assignments because there is more flexibility.

Q: When do NOAA Corps officers go to sea, and for how long do they stay?

A: After a 5-month training period, JOs are sent straight to sea assignments for 2 year periods. This can be extended or shortened by 6 months depending on what you are looking for in your next assignment. I extended my assignment at sea for 5 months so I could get my upcoming land assignment in California to work with dolphins for 3 years. After the land-based assignment, NOAA officers typically return to sea as operations officers, then back to land, then sea as executive officers, and so on. That is how you move up.

Q: What exactly will you be doing when you are on your next assignment in California?

A: The title of my position will be Cetacean Photo Specialist. I will be in La Jolla, CA, doing boat and aerial surveys, lots of GIS work and spatial surveys of marine mammal populations. I will participate in the center’s marine mammal stranding network. I will also be involved with outreach and education, which includes giving tours and presentations on scientific studies happening at the lab.

Q: Is life at sea different from what you expected?

A: Actually, it is easier than I thought it would be. I have always been a homebody and lived near my parents, I’m always busy here so time flies. I have internet and phone service so I still feel connected.

Q: Where did you go to college, and what degree did you earn?

A: I attended the University of Georgia, and earned a B.S. in Biology with a focus in marine biology.

Q: When / how did you decide to pursue a career in science?

A: When I was a kid I went to Sea World and fell in love with the whales and dolphins. I always loved animal planet. I also considered being a veterinarian for a while. I tried to be realistic because it is hard to land a career as a marine biologist, but I interned at a lot of places and made connections so I could do what I wanted to do.

Q: How did you find out about careers with NOAA?

In college, I took a summer course about marine mammals and toured a NOAA lab. About a year later, in June, my uncle saw the NOAA Ship Nancy Foster in port in Georgia, and I talked to someone on board about the work they were doing at sea. I immediately applied, interviewed, and was commissioned in January. It all happened very fast once I found out about it.

Q: You were one of the divers who recovered the missing trap this week. How long have you been diving?

A: I was certified to dive when I was 18. It is amazing, and something everyone should try. When I became an officer, the first thing I did was beg my command to send me to the NOAA Dive Center for training as a working diver.

Q: If a high school student is interested in a career like yours, what advice would you give?

A: Do a lot of volunteer work before you expect to get paid. You are investing in your future. If you want it bad enough you have to make sacrifices – but it will pay off. Make connections. If a marine biologist gives a presentation at your school, hang out after and talk with them. Ask for their email address and follow up. It’s a small world in marine research and networking is key.

Q: What is your favorite marine animal, and why?

A: I love thresher sharks and octopuses, but I’ll say Orcas. I’ve always found their species-wide diversity fascinating.

Personal Log:

There are so many people on this cruise who scuba dive and see amazing things below the sea surface. I have only snorkeled. I see dive certification in my future!

Did You Know?

The NOAA Commissioned Officer Corps is one of the seven uniformed services in the United States. Their motto is “Science, service, stewardship”.

Chart and control panel on the bridge

July 30, 2015August 21, 2021

Leah Johnson: Career Spotlight: Survey Technician, July 29, 2015

NOAA Teacher at Sea
Leah Johnson
Aboard NOAA Ship Pisces
July 21 – August 3, 2015

Mission: Southeast Fishery – Independent Survey
Geographical Area of Cruise: Atlantic Ocean, Southeastern U.S. Coast
Date: Wednesday, July 29, 2015

Weather Data from the Bridge:
Time 12:13 PM
Latitude 033.707470
Longitude -076.827550
Water Temperature 25.8 °C
Salinity 37.1618 ppt
Air Temperature 29.2 °C
Relative Humidity 75 %
Wind Speed 16.08 knots
Wind Direction 25.88 degrees
Air Pressure 1013.2 mbar

Science and Technology Log:
Career Spotlight: I would like to introduce everyone to Danielle Power, the Survey Technician on NOAA Ship Pisces. She was kind enough to let me interview her today.

Editing map area coordinates in the acoustics lab

Q: What is the role of a survey technician (ST) on this ship?

A: The survey technician keeps track of scientific equipment and spaces. This includes calibrating sensors and maintaining and repairing equipment. When science parties are on the ship, the ST assists with data collection and oversees CTD operation.

Q: Does this job description vary depending on the ship?

A: Yes. On the Nancy Foster and other ships with big dive platforms, STs do a lot of diving and deck work. There are often two STs on board, each working a half-day shift. These STs do not work so intensively with fish. Hydrographic vessel STs deal with mapping and tide station installs.

Q: What do you like best about your job and being at sea?

A: My favorite thing about life at sea is that there are no bugs, and I don’t have to deal with allergies! I also meet awesome people on every cruise. Every trip is a little different, so I am always learning new things.

Q: What do you find to be the most challenging aspect of your job and life at sea?

A: Being at sea for a long time, all the time, is taxing.

Q: Is life at sea different from what you expected?

A: Yes. This job requires living with 20 other people in a confined space all the time, and it isn’t easy. I didn’t fully realize this back in college. I don’t have easy access to things I might want or need. I also have to give up certain aspects of social life. You can’t just take a day off, you have to take an entire leg of a cruise off (up to 2 weeks), which is a lot of money to not be making and a lot of work to be missing. So I have to miss some big events for important people in my life, like weddings and holidays.

Q: Where did you go to college, and what degree did you earn?

A: I graduated from Old Dominion University in Norfolk, Virginia. I earned a B.S. in biology with a concentration in marine biology.

Q: When / how did you decide to pursue a career in science?

A: In 6^th grade, I went on a family vacation to Disney world. I went to Sea World, and it ignited my love for all things ocean. I have stuck with it ever since.

Q: If a high school student is interested in a career like yours, what advice would you give?

A: Work hard, and get a college degree that is relevant. Make sure you know that this is a job you truly want to do. Find internships and experience life on a ship before you commit. If you enjoy it, then make the most of the career and all of the opportunities that come with it.

Q: What is your favorite marine animal, and why?

A: An Octopus! Cephalopods are very intelligent creatures, and I love that they can blend into environments so well that they cannot be seen. They can change not just their color, but their texture. They are so interesting! They can go into small spaces, because they can fit anywhere their beaks fit and they use parts of their environment as tools.

recording data in the wet lab

Personal Log:
I am blown away by all of the different jobs that need to be filled while out at sea. Working on a boat was something that I never even considered when I was in high school. The idea just never occurred to me, and I didn’t know anyone at the time who did anything like this. There are so many interesting career opportunities that exist, and new types of jobs will develop as needs and technology change over time.

Read all about career opportunities with NOAA here!

Did You Know?

NOAA stands for “National Oceanic and Atmospheric Administration”. It officially formed in 1970, but the environmental agencies that came together to form NOAA originated in the 1800s. Learn more about NOAA’s history here.

July 28, 2015August 21, 2021

Leah Johnson: Trap Recovery, July 27, 2015

NOAA Teacher at Sea
Leah Johnson
Aboard NOAA Ship Pisces
July 21 – August 3, 2015

Mission: Southeast Fishery – Independent Survey
Geographical Area of Cruise: Atlantic Ocean, Southeastern U.S. Coast
Date: Monday, July 27, 2015

Weather Data from the Bridge:
Time 12:38 PM
Latitude 034.384490
Longitude -076.576130
Water Temperature 23.75 °C
Salinity -No Data-
Air Temperature 30.8 °C
Relative Humidity 62 %
Wind Speed 10.15 knots
Wind Direction 88.23 degrees
Air Pressure 1014.8 mbar

Science and Technology Log:
As I mentioned in an earlier post, flexibility is key. Things don’t always go according to plan. Originally, we were going to head northeast from Morehead City Port, but the weather did not cooperate with us. We headed south to avoid a large storm, and then moved closer inshore. This forced us to choose some different areas to sample. Most of our sample sites are situated over the continental shelf between Cape Fear and Cape Hatteras. Tomorrow we hope to move to deeper waters beyond the shelf break.

Map of Pisces route so far. Image from Shiptracker.

On July 23, we lost a trap. After one of the deckhands threw the hook out to catch the buoy rope and started the winch, the rope went taut and then snapped. Occasionally this happens because the traps can shift and become wedged under or hooked onto a rocky ledge on the seafloor. We do our best to avoid this, but it happens. This is why it is important to have extra traps, cameras, and camera housings on board.

Map showing positions of two lost traps. Water depth is shown in feet.

We planned to retrieve our trap the following day, but the storm chased us out of the area. Two days later, we lost a second trap! Unfortunately, this one was too deep to recover on a dive. The traps we deploy have zinc clasps that dissolve after ~24 hours, so fish can eventually exit the traps on the off chance that we are unable to retrieve them. Still, we don’t want to simply abandon traps on the seafloor or run short on gear, so we made plans to retrieve the first trap. We just had to remain patient and hope for calmer seas. Finally, our window of opportunity opened up today.

The small boat is on a davit on the 01 deck.

A small boat is located on 01 deck near the stern of NOAA ship Pisces. The deck chief oversees operations as it is lowered for the divers, the dive master, and deckhands to board. They take an inflatable buoy and rope with them, and then head out to the coordinates of the trap. The divers descended ~20 meters to the shelf where the trap was indeed wedged on a rocky ledge. First, the divers removed the two GoPro cameras that were attached to the trap. Next, they secured a rope attached to a buoy on the trap. The ship will then be able to use this buoy to retrieve the trap as typically done. The divers ascended the line and were picked up with the small boat.

The small boat returns after successfully finding the trap.

The deckhands then attached our standard buoys to the rope, and returned to the Pisces. The divers climbed up a rope ladder on the starboard side of the ship, and the small boat was hoisted up. We then hauled up the missing trap like we would any other. The trap was empty, and all of the bait was gone – not surprising after a 4-day soak!

Personal Log:

I make a point to stand near the bow of the ship and watch the sea and sky for a while every day. I usually see some flying fish, which are fun to watch. They zip out of the water, dart across the waves, and then dive back under. One of them landed on deck after a storm, so I had a chance to see one up close.

Flying fish

The skies are beautiful, too. I have seen some impressive clouds and gorgeous sunrises and sunsets. The view is completely unobstructed, so I can just take it all in without distraction. I find it all very peaceful.

The skies at sea are stunning.

Did You Know?

After otoliths and tissue samples are collected from the fish we keep, the fish are filleted, frozen, and donated to local food banks.

Collecting tissues from a fish.

July 27, 2015August 21, 2021

Leah Johnson: Physical and Chemical Properties of Ocean Water (There’s More Here Than Just Fish!) , July 26, 2015

NOAA Teacher at Sea
Leah Johnson
Aboard NOAA Ship Pisces
July 21 – August 3, 2015

Mission: Southeast Fishery – Independent Survey
Geographical Area of Cruise: Atlantic Ocean, Southeastern U.S. Coast
Date: Sunday, July 26, 2015

Weather Data from the Bridge:
Time 12:38 PM
Latitude 34.24389
Longitude -76.6625
Water Temperature 23.75 °C
Salinity –No Data-
Air Temperature 28.6 °C
Relative Humidity 68 %
Wind Speed 12.6 knots
Wind Direction 67.01 degrees
Air Pressure 1014.8 mbar

Science and Technology Log:
The primary purpose of this cruise is to survey reef fish. Our main task is to collect data pertaining to presence and number of fish species, species length frequency, and sample materials for fish age and growth. However, other types of measurements are being made as well. For example, the CTD is an instrument that measures different properties of ocean water with depth. It is deployed every time the fish traps are dropped.

The CTD sits on the starboard side of the deck of NOAA Ship Pisces.

The acronym “CTD” stand for conductivity, temperature, and depth. The instruments that measure these properties are affixed to a metal cylinder called a rosette. A range of sensors can be attached depending on what needs to be measured. Additionally, containers can be attached to the frame in order to collect sea water samples at different depths. When the ship reaches the designated coordinates, the survey technician calls to the deckhands and instructs them to use the winch to lower the CTD to a designated depth, and then haul it back up.

Deckhands assist with lowering the CTD.

Below you can see a graph of the data collected earlier in the week:

CTD Data

The y-axis represents depth in meters. The CTD actually measures water pressure, which is then converted to depth. Pressure and depth are directly related: as depth increases, pressure increases.

There are several different properties represented on the x-axes, shown in different colors:

light green = oxygen (mg/l)
orange = conductivity (S/m)
dark green = temperature (°C)
purple = salinity (PSU, or ppt)

What do these measurements mean? As depth increases, temperature decreases. Sunlight warms the sea surface, and wind and ocean currents distribute this heat energy throughout the upper waters. Beneath this mixed layer, temperature decreases steadily with depth. In deeper water (not at this location), this rate of change decreases and the temperature of deep ocean water is nearly a constant 3 °C. Salinity refers to the concentration of dissolved salts in the water. Average ocean salinity is 35 ppt (parts per thousand), though this varies by a few parts per thousand near the surface. Increased precipitation, runoff, or melting of sea ice can decrease salinity, and evaporation and ice formation can increase salinity. Conductivity (measured in Siemens per meter) is a measure of how much current can travel through the water, and this is affected by both salinity and temperature. Finally, fish and other marine organisms require dissolved oxygen to breathe. By measuring the amount of oxygen at different levels in the water column, we can determine how much sea life can be supported in a given area. Dissolved oxygen in the ocean comes from mixing at the surface, and is also produced by photosynthetic organisms. As temperature and salinity increase, dissolved oxygen levels decrease. Additionally, temperature and salinity data can be used to determine the water density, or the mass of water per unit volume. Different fish can tolerate certain ranges of all of these chemical and physical parameters.

With respect to the fish survey, this information is important because we can monitor the conditions of the water near the ocean floor where the traps are located. For scientists who are interested in characterizing reef fish habitat, this data is a critical component of their research.

There are other ways in which this data can be used. The depth profiles of each of the chemical and physical properties at a given site can be compared to other local sites in order to identify any spatial anomalies. This is of great interest for seafloor mapping and ocean exploration cruises. For example, a change in conductivity and temperature at a site in the middle of the ocean could indicate the presence of a hydrothermal vent. Or, a decrease in salinity in a region along a coastline could indicate freshwater runoff.

Additionally, as measurements are made at similar locations over a period of time, temporal changes may be observed. This could reveal seasonal changes, or a long-term trend. Because we are observing an increase in average global temperatures and experiencing global climate change, it is critical to collect data that can be used to assess changing ocean conditions.

Personal Log:
“Will you be eating a lot of fish on the ship?” I heard this question a lot before I left for this cruise. I wondered myself. It seemed reasonable that fish would be prepared for meals because, well, we will be living at sea! On the other hand, I wondered if everyone on board would be sick to death of fish because we would be looking at them all day. As it turns out, fish is prepared for nearly every meal; however, there is often another meat option, as well as a variety of other non-meat dishes. Now we know!

Ship mess

Did You Know?
There are many fish that make a grunting sound. When we have tubs full of tomtates in the wet lab, it sounds like a bunch of miniature pigs making snorting noises!

Still from video of tomtates near a trap. A nurse shark can be seen in the background.