Category: 2017

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Karen Grady: Sometimes You Find A Little Something Extra, April 16, 2017

NOAA Teacher at Sea

Karen Grady

Aboard NOAA Ship Oregon II

April 5 – April 20, 2017

Mission: Experimental Longline Survey

Geographic Area of Cruise: Gulf of Mexico

Date: April 16, 2017

 Weather Data

Latitude 2848.37 N
Longitude 09247.66 W
76 degrees
Sunny
No precipitation
Winds at 11 KTS
Waves at 2-4 FT

Science and Technology Log

Sometimes when a shark or fish is brought on board it has a “hitchhiker’ attached. We caught a blacknose shark that had a common remora, often referred to as a sucker fish, or shark sucker, attached to it. Scientist Kevin Rademacher placed this sharksucker (Echeneis naucrates) on my arm. I couldn’t really feel it but he was stuck there until I peeled him off. It was like peeling a piece of tape off. You can see from the photo how he is designed to attach to host species. Their head is actually a modified dorsal fin that has an oval shaped sucking disk with slat-like structures that open and close to create suction and take a firm hold against the skin of its host animal such as a shark, turtle, whale, or ray. By sliding backward, the remora can increase its suction, or it can release itself by swimming forward. They can be small like the one attached to my arm or they can grow to over two feet in length. The remora can move around on the host, removing parasites while at the same time gaining protection provided by the host. This relationship is often looked at as one of commensalism where both the host and the remora benefit.

The remora’s modified dorsal fin provides suction ability
Remora on TAS Karen Grady’s arm
Remora
Remora

Photos of the remora that was attached to a black-nosed shark.

When one hears that this is an experimental long-line survey of sharks and reef fish, all you think of is catching these creatures and collecting data. However, scientists are collecting data about the environment as well. It is very useful to obtain information about the water where they catch large numbers of a species and areas where they may not catch anything. One way they can do this is by using a Conductivity Temperature Depth Profiler (CTD).

The CTD gives scientists a profile of the water column where we just put out our line. The CTD has sensors that collects information on oxygen levels, temperature, water clarity, chlorophyll concentration, and salinity. The CTD is placed in the water and allowed to sit for three minutes to let the oxygen sensors soak and adjust from being on the deck and lowered into the water. The crew lowers it to a depth that is decided based upon the depth to the ocean floor. They like to take it as close to the bottom as possible in order for the information they gather to be as complete as possible. It is allowed to settle, run its scans and then is brought back up to the surface and the sensors are flushed with fresh water. The data is automatically loaded into the database. This information is collected at each station. It takes a joint effort of the deck, science and bridge crews to place the CTD in the water. Walkie talkies are utilized for communicating between all the crew involved in the operation.

Scientist James Sulikowski prepares the CTD for deployment
Scientists can review the data from the CTD immediately

Personal Log

Being at sea with Easter approaching had its moments when I thought of family and friends. We have our Easter traditions and I would be missing them this year. The Easter Bunny (Field Party Chief, Kristin Hannan) decided we needed an early visit this year. I think she was right. The surprise and the treats perked all the science staff up.

TAS Karen Grady 4-16-17 Easter basket

FPC Kristin Hannan asks me often if I have any questions about what they are doing or anything in general. I will be honest… I have gotten so caught up in what we are doing, trying to do my best at whatever job I am working on, and being in awe that I am actually out here that I forget to ask questions about the details. I love the anticipation of what might be on the next hook, I am mesmerized by the sleek lines of the sharks when we have them on board.

TAS Karen Grady 4-16-17 shark liver
Shark liver

When we had one come onboard that was dead due to low oxygen levels in the water where we caught it, we did a dissection on the deck while we waited to put out another line. The animal science nerd in me came to life!   I had no idea the liver was the largest organ inside a shark. Think about it …these creatures have no body fat and they store their energy in the liver. Then we looked at the intestines. There is not a lot of room in there so the shark we looked at the intestines are rolled up like you would roll a piece of paper. This gives them maximum absorption area but takes up a limited space.

 

 

 

One thing I think of as we are catching these species is that very few people stop and think about the actual research scientists do to help understand what is needed to maintain healthy populations. It is necessary to do these surveys, catch the species, tag some, draw blood, take fin clips, keep whole specimens, and dissect some. On our cruise we were lucky enough to ultrasound a few pregnant sharks and see the pups inside.

TAS Karen Grady 4-16-17 shark ultrasound
Baby sharks visible on ultrasound

Now stop and think about all those things I just listed that we do at times. When a hook comes up and there is a fish or shark on it is handed off to one of the science crew.  It is noted in the computer that there was a something caught. The science crew member will take measurements and weight of the fish or shark. If it is a shark, the sex will be noted and some species may be tagged, have a fin clip taken and blood drawn. While all of these activities are taking place, the next hooks keep being brought up. The deck can get pretty crazy if there are several hooks in a row with something on them. The data collector has to keep tag numbers, species, measurements, samples and weights all written in the correct spot while having two or three people calling them out for different fish and or sharks. I had experience working cattle which would mean filling syringes, writing down tag numbers, filling taggers, etc. But this is even crazier than that could get at times. And everything stops if someone calls “hardhats” because that means we have one big enough for the cradle. Working back writing down data or taking measurements you can’t see what is on the next line so you sneak up for a peak when they say it’s a big one then you get out of the way.   One of the best experiences so far was almost getting a big tiger shark in the cradle. I was lucky enough to get a video of her, so stay tuned! Unfortunately, when the big shark brushed against the cradle she snapped the line and was gone with a huge spray of water.

This second leg of the experimental long-line survey is winding down. There have been long days but they are filled with laughter, giggles, anticipation, excitement, teachable moments (I can finally get the circle hooks out by myself…sometimes) , and the dreaded words “snapper.” I mean nothing against the Red Snapper, they are a bright colorful and tasty fish, but when you are hoping for a shark to be on the hook…. let’s just say the sets where we get 12 snapper and two sharks are not our favorites.

Photos: “Shark!” or “Fish on!” means a busy deck.

TAS Karen Grady 4-16-17 hammerhead cradle
Scalloped hammerhead shark

When the guys at the rail grab the hard hats it means it is time for the cradle and we get to see things like this gorgeous scalloped hammerhead. Things move very quickly when one is in the cradle. Safety for those on deck comes first and everyone is focused on getting measurements, fin clip and a tag on the shark and getting it safely back in the water as quickly as possible.

TAS Karen Grady 4-16-17 baby tiger shark
Baby tiger shark

Baby tiger shark in the cradle. They warned me that they were cute and they were so right. Yes, a shark can be “cute” when your referring to baby tiger sharks and baby hammerheads!

Did You Know

Sharks store energy in their liver. It is the largest organ in their body. The heart on the other hand is extremely small in comparison to the size of the shark.

TAS Karen Grady 4-16-17 hammerhead dissection
Dissected scalloped hammerhead with liver visible

Look at the liver of this scalloped hammerhead. It is amazing how big it is in relation to the body of the shark. This is just one way these amazing creatures are designed to be efficient and survive in their underwater world.

Sharks have a nictitating membrane that they can close over their eye for protection. When a shark is brought on deck you can touch near the eye and the membrane will automatically move to close.

TAS Karen Grady 4-16-17 nictitating membrane
Nictitating membrane partially closed on the eye of a scalloped hammerhead
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Mark Wolfgang: Fish Eggs, I Will Take Mine Over Easy; April 15th, 2017

NOAA Teacher at Sea

Mark Wolfgang

Aboard NOAA Ship Reuben Lasker

April 11 – April 22, 2017

 

Mission: Spring Coastal Pelagic Species (Anchovy/Sardine) Survey

Geographic Area of Cruise: Pacific Ocean

Date: April 14, 2017

Weather Data from the Bridge:

Lat: 35o 47.1’N         Long: 122o 58.8’ W

Temperature: 14.9oC (59oF)

Wind speed: 29 knots

Barometer:  1020.92 mbar

Conditions: Windy, blue skies with a few clouds, choppy seas

Scientific and Technology Log:

The research into the fish that live in this area of the Pacific Ocean investigates the entire life cycle.  The night trawls will usually catch adults or juveniles.  There are other techniques to collect eggs and larvae.  One of these techniques is a Continuous Underway Fish Egg Sampler (CUFES).

DSC00050
The Continuous Underway Fish Egg Sampler (CUFES)

There is an intake valve 3m under the surface of the water and it is collecting water (and anything living in it) all the time.  As the Reuben Lasker moves along a transect water is collected through this machine and filtered.  Every 30 minutes, the specimens that have been collected are removed, counted, and identified under the microscope.  The samples are then rinsed into small vials, preserved in formalin and are labeled and stored.  On this survey, they are looking for sardine, anchovy, jack mackerel, hake, and squid eggs.  The sample also has numerous copepods, but those are not counted and recorded.  So far, we have found mostly jack mackerel and squid eggs which are reflected in our catches during the night trawl.

A second technique involves nets dropped off the side of the ship.  The first is net called a

DSC00040
Deck hands and the chief scientist deploying the pairovet from the side station

pairovet.  A pairovet is a vertical plankton tow.  The net is dropped off the side of the ship
to a depth of 70 meters.  The net stays in place for 10 seconds and then are pulled back up.  The specimens collected are rinsed into containers.  One net’s collection is placed in formalin, a preservative, for later identification, while a second net’s collection is placed in ethanol for possible DNA analysis.  The other net is called a Bongo Net.  This net is an oblique tow and is dropped to a depth of 210 meters and is pulled in at an angle of 45o.  The contents are preserved for later identification and possible DNA testing.  The pairovet has a finer mesh to the net, so it collects smaller zooplankton and icthyoplankton.

DSC00046
The Bongo net being lowered into the waters off of Big Sur

 

The trawls on the night of the 12th had some Jack mackerels, some larger squid, a couple octopi, and a single sardine.  For the Jack mackerel and sardine, we recorded their length

DSC00035
Jack Mackerel

and mass.  We also took tissues for DNA analysis as well as the gonads for female sardines, anchovies, Jack mackerel, and Pacific mackerel.  These will be used for histology and fecundity studies.  Fecundity is the ability to produce an abundance of offspring or their fertility.  We remove a small, hard structure called the otolith.  The otolith is found in the inner ear and maybe used for balance.  The otolith can be used for aging the fish.  We had high winds on the 13th, so we were only able to one trawl.  Ironically, we watched “Finding Dory” while we waited for the bridge to say it was safe to let out the trawl nets.  We didn’t find her.

Personal Log:

It has been quite challenging changing my sleeping schedule.  Not only am I all screwed up with the 3 hour time difference from home, I am currently working the night trawls from 6 pm to 6 am, although the heavy work doesn’t begin until after sunset.  I was awake for 28 hours straight, but was able to get some sleep and relax some this afternoon.  I got a chance to call home and talk to my family.  It has been difficult being away from them and not getting a chance to talk, but I had that opportunity today.  For that I am thankful.  There were some plans to fly the drone when we arrived at the coast of Big Sur, California, but the winds were too high to do so.  I continue to be impressed with the scientists and crew.  I love watching the team work – it is quite impressive.  As we moved up the coast today, I took a few minutes to look around and soak it all in.  Big Sur was beautiful, the sky was clear with only a few clouds, and the water was a deep rich blue.  It was gorgeous.  I am so glad I took a moment to realize how lucky I am.

DSC00038
Big Sur, California

 

Did you know?

The Pacific Ocean is the biggest ocean in the world.  It contains 30% of the space in the earth and contributes half of the water to the world.  It is also the deepest ocean in world, counted at 3800 m.  I am currently traveling through the Northern Pacific Ocean.

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Karen Grady: One Fish Two Fish Red Fish …… Weird Fish, April 10, 2017

NOAA Teacher at Sea

Karen Grady

Aboard NOAA Ship Oregon II

April 5 – April 20, 2017

Mission: Experimental Longline Survey

Geographic Area of Cruise: Gulf of Mexico

Date: April 10, 2017

Weather Data

Latitude 2827.10
Longitude 09148.6
75 degrees
Sunny
No precipitation
Winds at 10 KTS
Waves at 2-4 FT

Science and Technology Log

We have continued to move between deep stations setting the baited line and hoping to catch deep water fish and sharks. These deep sets require longer soaking time to allow the hooks to reach the bottom.   The downside is that we have been retrieving one set of gear and putting out one set of gear in a 12 hour period of time. Some sets have a few fish and some we get a big goose egg.   There is always anticipation though as the 100 hooks are brought up. Everyone stands in their spots waiting to hear either “fish on,” “shark” or everyone’s favorite, “hard hats!” which means there is a big shark and it’s time for the sling. Below you will see the awesome Great Hammerhead (Sphyrna lewini) we caught.

TAS Karen Grady 4-13-17 great hammerhead
Great Hammerhead Shark

The first few days we have been fishing deep in the Mississippi Canyon. The Mississippi Canyon is a geological formation in the Gulf of Mexico. It is located in an area which is part of the territorial waters of the United States. We put out some deep lines with the deepest at 1900 feet. These lines soaked four hours once fully deployed.  They soak longer because they have so far to sink to get to the depth the scientists want to fish at. When we deploy a line the first thing in the water is the High Flyer, which stands like a beacon and bobs in the water marking the start of our fishing line. The next thing over the side of the ship is a weight that helps carry the line to the desired depth. Halfway through, another weight is deployed, and after the 100th hook, the third weight goes in.   The last thing over is another High Flyer to mark the end of the line. If it is dark outside, the High Flyers have lights attached on top that flash so that they can be seen.

TAS Karen Grady launching high flyer
“High Flyers” mark the beginning and the end of the long line set.

At our last deep station we caught a Mexican Grenadier, Coryphaenoides mexicanus. This fish is very unusual in color and appearance. If you feel the scales on the fish you find that they are very unique. Each scale has tiny sharp, thin spinules. As you run your hand over the fish you can feel these scale modifications. The eyes are bulged due to the pressure change of coming up from such deep depths. The scientists determined the sex of the Grenadier and then it was frozen for future study.

TAS Karen Grady 4-13-17 grenadier
Mexican Grenadier

We also caught two Cutthroat Eels, from the family Synaphobranchidae, that were both females. Synaphobranch means unified gill… the two gill slits join together making it look like a cut throat. They are bottom-dwelling fish, found in deep waters. The eels were weighed, measured, and the scientists determined the sex and maturity of each eel. It is important that they make accurate identification of specimens and collect data. The scientists work together using personal knowledge and books when necessary. There are times on deck when the scientists will stop to examine a species and will take multiple pictures of certain identifying parts so that they can look at them closely later.

Examining a cutthroat eel
The scientists work together and reference books to identify specimens.

 

Personal Log

One of the great things during a watch is being able to talk with the scientists. I am an avid listener and observer. This is what they do year in and year out and they love what they do. I am a quiet observer a lot of the time. I listen and then ask questions later. It’s not exactly easy to carry around paper and pencil to take notes. But during the transit portions or soak times I ask more questions and gather information to share in my blog posts or for the lesson plan I will be writing when I get home.

The food has been great here on the ship. Our stewards have fresh salads, and menus that include two main course options, a daily soup, dessert and multiple side choices.   There are snacks available 24/7 so you are never hungry. Because the meals are so great you see most people trying to fit in a workout during the day. I have been introduced to the Jacob’s ladder for workouts. I never liked hills and now I can say I don’t like climbing ladder rungs either. That machine is evil!! However, I will continue to do cardio on it as the food is excellent and keeping food in your stomach helps prevent sea sickness. I will happily eat more than I usually do if it means I don’t get seasick. An example of a typical lunch would be today when we had choices of salad, reuben, tuna melt, french fries, sweet potato fries, cookies and several other sides.

Today started with us catching two Cutthroat Eels and a Mexican Grenadier. You can see from the pictures I have posted that they look very different from most fish that you see. They really are that color. It was a shock after the sleek sharks and the bright orange Red Snapper I had seen on previous sets. I was busy watching the scientists using their books and personal knowledge to identify each species accurately.   After we finished the work up on the fish we caught we headed for the next station. Now we are back to shallower fishing and expect to catch sharks, red snapper, and a variety of other fish.

TAS Karen Grady 4-13-17 grenadier and eels
Two cutthroat eels (top) and Mexican grenadier (bottom)

I can honestly say that the 12 hour shifts start wearing you down, and sleeping is not an issue once you climb under the covers. The waves will wake you up now and then. And some mornings I wake up and can smell them cooking breakfast but sleep overrides the smell of food because I know how long it will be till I get to bed again. Walking out on deck each morning to views like this does lead to a smile on your face, that and the music that is playing loudly on the deck. Yesterday it was Hair Nation…. taking me back to the 80’s.

TAS Karen Grady 4-13-17 blue water
View from the deck of NOAA Ship Oregon II

Did You Know?

The Gulf of Mexico is roughly 995 miles along its longer, east-west axis. It has a surface area of about 600,000 square miles.

A wide variety of physical adaptations allow sharks to thrive in the Gulf of Mexico. They have powerful smell receptors. The sensory organs lining their prominent snouts, called ampullae of Lorenzini, can detect movement of potential prey even if the sharks cannot see it. These sensory organs assist in trailing injured marine animals from great distances. They help sharks locate all sort of other things, too– shrimp boats, other sharks, birds, turtles (tiger sharks a big turtle eaters!), even boats that are dumping trash.

The skin on a shark is smooth if you run your hand head to tail and rough like sandpaper if you run your hand from tail to head. At one time, sharks skin was used as a form of sandpaper. The dermal denticles, or skin teeth, can be different from species to species and can sometimes be used as a character to look at when trying to identify one species from another.

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Emily Sprowls: Whirlwind Return to Shore, April 11, 2017

NOAA Teacher at Sea

Emily Sprowls

Aboard NOAA Ship Oregon II

March 20 – April 3, 2017

Mission: Experimental Longline Survey

Geographic Area of Cruise: Gulf of Mexico

Date: April 11, 2017

Weather Data

The weather on the last scheduled day of the cruise was so bad (12 ft. seas! 30 knot winds!) that the ship came into port early on Sunday. The strong winds and waves kicked up and a string of severe storms and tornadoes swept through the area just after my flight home left on Monday morning.

Science and Technology Log

The last few days of the cruise brought in a lot of sharks, fish and data. We were kept pretty busy, putting in and hauling out 3 or 4 lines each shift. In total between both shifts we set 53 stations and caught 679 vertebrate specimens (not counting the invertebrates: sea stars, sea cucumbers and all those isopods)! There were points when this was totally exhausting and repetitive, but then there were moments when we were holding sharks and it was all worth it! We caught some amazing creatures, and some just floated or flew by for a visit like jellyfish and migrant birds.

In between stations the scientists worked to collect and label tissue samples from the specimens needed by different research labs, including fin clips, parasites, muscles, and eye lenses.

Migrating songbird visitor
Portuguese man-o-war jelly
Tissue specimens from bony fish

Personal Log

To be completely honest, there was a point about two-thirds through the cruise when I felt pretty tired, a little bit nauseous, and like I had already seen and learned so much that I was ready to go home. That happened to be a day when another thunderstorm blew in, and we had to take a break from sampling. That terrific weather break (during which we lounged with popcorn and a not-so-terrific movie) also coincided with the forecast suggesting a possible early end to the cruise. Suddenly, it seemed like my trip was almost over — I realized that I had so many more questions for my new scientist friends and not enough time to learn everything!

Fortunately, the scientists on board were very kind and eager to answer my students’ questions with the best information they could find. We had several engaging discussions while answering the kids’ questions… in fact, at one point we were so engrossed in a conversation about dogfish life history that we were suddenly interrupted by radio calls from the deck and bridge that we had missed hauling in our line! We grabbed all our gear: boots, gloves, life jackets, hardhats, clipboards, cameras, laptop; and ran out on deck as fast as we could muster. We had all forgotten it was April Fool’s Day! Ha!

Oregon2 crew
NOAA Corps Officers LCDR Lecia Salerno, LT Reni Rydlewicz and ENS Chelsea Parrish

I am so grateful to the entire crew for their hospitality and their willingness to teach me about their jobs. They shared not only their homes on the boat, but also their own stories and knowledge about the work we were doing. I was lucky to share my first boat experience with Ensign Parrish, who was on her first cruise as a newly minted NOAA officer. Her infectious smile and clear love for being at sea, all while learning the ropes of the Oregon II, helped pull me right along with her enthusiasm.

The main person responsible for my excellent experience aboard was the Field Party Chief.

Baby tiger shark
The amazing shark wrangler Kristin Hannan with a young tiger shark!

Kristin Hannan was friendly and generous with her time, all while coordinating stations with the bridge, managing the scientific crew, and preparing for the next research trip. She was also indefatigable! By the time I would get my baiting gloves off, catch my breath, and get ready to help clean up, she had already finished scrubbing the barrels and decks! Most endearing, however, were her encyclopedic knowledge of shark anatomy and population ecology, and her love of all things shark (even the movie JAWS), tempered by a clear, rational, scientific perspective on issues facing the Gulf of Mexico.

Eventually, the trip drew to a close. As we approached the final sampling stations, there were many species I had hoped to see that hadn’t come up yet. It was as if all I had to do was wish for them and they appeared in the final hauls: Stingrays – CHECK! Big bull shark – CHECK! Beautiful baby tiger shark — CHECK! Adorable spinner shark — CHECK!

I started to see why this work was so addictive and attractive to the crew. But, at the end, I was definitely ready to be on stable land and order whatever I wanted from a restaurant. Going home to my incredibly spacious queen-sized bed and enormous 50 square foot bathroom was also quite nice! I loved my adventure at sea, while I also so admire the tenacity and grit that the scientists and crew on the Oregon II have for living the boat life for much, much longer than two fun weeks. Thank you!

Kids’ Questions

What types of sharks will you catch in the Gulf?

On our leg, we caught the following shark species:

Scalloped hammerhead
Scalloped hammerhead
  • Blacknose shark , CARCHARHINUS ACRONOTUS
  • Spinner shark, CARCHARHINUS BREVIPINNA
  • Blacktip shark, CARCHARHINUS LIMBATUS
  • Sandbar shark, CARCHARHINUS PLUMBEUS
  • Gulper shark, CENTROPHORUS GRANULOSUS
  • Little gulper shark, CENTROPHORUS UYATO
  • Tiger shark, GALEOCERDO CUVIERI
  • Dusky smoothhound shark, MUSTELUS CANIS
  • Gulf smoothhound, MUSTELUS SINUSMEXICANUS
  • Sharpnose shark, RHIZOPRIONODON TERRAENOVAE
  • Scalloped hammerhead shark, SPHYRNA LEWINI
  • Cuban dogfish shark, SQUALUS CUBENSIS

 

 

Clearnose skate
Clearnose skate

We also caught the following batoid species:

  • Southern stingray, DASYATIS AMERICANA
  • Roughtail stingray, DASYATIS CENTROURA
  • Bullnose ray, MYLIOBATIS FREMINVILLII
  • Clearnose skate, RAJA EGLANTERIA

 

What is the most populous type of shark in the Gulf of Mexico?

Sharpnose sharks were the most common in our sampling (we caught 247!) Bonnethead sharks are the more common species closer to shore, and blacktip sharks tend to be more common out farther to sea.

Are some shark species more or less sensitive to pollution?

Bull sharks are tolerant of extremes in water conditions (they have been found in the Mississippi River!), so they may be less sensitive to pollution. In general, hammerhead species are more sensitive and younger sharks are also in sensitive life stages, so they might be more sensitive. This is exactly the kind of questions that scientists might be able to answer more definitively someday using the large amounts of data collected by the Oregon II.

What are sharks’ lifespans?

Each shark species is different, but generally they live a long time. Small sharpnose sharks can live about 10 years. Dogfish can live up to 70 years. Other sharks average about 30 years. There is speculation that a Greenland shark has lived over 100 years! These long lifespans are part of the reason many shark populations are vulnerable because it takes them a long time to reach maturity and they do not reproduce quickly. Life history information about sharks is important to know as the NOAA scientists help manage fisheries.

 

 

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Mark Wolfgang: First Impressions, April 12, 2017

NOAA Teacher at Sea

Mark Wolfgang

Aboard NOAA Ship Reuben Lasker

April 11 – April 22, 2017

 

Mission: Spring Coastal Pelagic Species (Anchovy/Sardine) Survey

Geographic Area of Cruise: Pacific Ocean

Date: April 12, 2017

Weather Data from the Bridge:

Lat: 35o 21.1’ N            Long: 121o 26.9’ W
Overcast, rainy with quite a bit of fog
Temperature: 14oC (56oF)
Wind speed: 9.26 knots
Barometer: 1015.17 mbar
Visibility: Very limited

TAS Mark Wolfgang 4-13-17 Mark on deck
TAS Mark Wolfgang on board NOAA Ship Reuben Lasker, passing under San Francisco’s Golden Gate Bridge

Scientific and Technology Log:

Last night/this morning, we did our first two trawls. These two trawls were kind of “blind” because they had not started doing acoustic trawls. I think I am starting to get the hang of how things happen during a trawl, which I know will be put to the test tonight.

TAS Mark Wolfgang 4-13-17 pulling in net v2
The deck crew reels in the trawl net

As the net is pulled in, a team goes out and removes the camera from the net. The camera is used to monitor the net during the trawl, as well as monitoring the MMED (Marine Mammal Excluder Device) which records animals and their condition as they encounter the metal bars and are excluded through the opening in the top portion of the net. The deck crew continues to pull in the net. The organisms collected in the end of the net are put into buckets and brought into the wet lab. The first trawl had a small sunfish in the catch, but I missed it because I was putting my foul-weather gear on.

TAS Mark Wolfgang 4-13-17 market squid
Contents of the trawl (mostly pyrosomes and market squid) on the sorting table

The organisms are dumped onto a table and sorted. After sorting, the organisms are put on the scale and the mass is recorded. The number and type of fish were recorded. Both trawls had mostly pyrosomes (a colonial tunicate) and market squid. I have taught about tunicates in my zoology class, but never knew they were so common in the Pacific Ocean. Other than the pyrosomes and squid, the two trawls contained some lantern fish, several red pelagic crabs, and some other very small fish as well as a moon jelly.

Since we had no sardines or anchovies to process, we focused our time on the market squid. A random sample of 50 squid are taken. For each squid, we measure the length of the mantle, place the squid on a balance and record the mass. If the squid were larger than 75 mm, the squid was given a tag and placed in a bag. The squid smaller than 75 mm are all placed together in a bag.

Measuring squid
Weighing squid

It was impressive how all team members got right to work and functioned like a well-oiled machine. I am also impressed with how all individuals think of safety first. Starting at sunrise, they began doing acoustic trawls, so we may have better luck catching sardines and anchovies tonight.

Personal Log:

I have enjoyed my first days on the Reuben Lasker. The crew and science team have been very accommodating and welcoming. I am trying to be helpful and not get in the way. My roommate is a UAS drone pilot, but the weather has not been good enough to fly today – it is quite foggy and rainy and the seas are choppy. I hope I get a chance to see it fly sometime soon. I am trying to get used to the sleeping schedule and since I couldn’t sleep this morning, I took a little tour today and went to the bridge and spoke to some of the crew on the bridge as well as the Commanding Officer (CO). They showed me around a little and described some of the different navigational equipment. The chief electrician showed me around the computers in the acoustic lab. It is crazy to see all of the technology and to hear about how they handle all of this data with limited internet access on the boat. I am so pleased that everyone was been so friendly. The food has been great (we had an incredible crème brulee last night) and I have not been sea sick so far.

Did you know?

Pyrosomes are colonies of hundreds of individuals known as zooids. These zooids are joined by a gelatinous tunic and work in unison to propel the colony through the water.