catch – NOAA Teacher at Sea Blog

July 3, 2019July 7, 2019

Karah Nazor: Cool Catch Highlights, June 2-7, 2019

NOAA Teacher at Sea

Karah Nazor

Aboard NOAA Ship Reuben Lasker

May 29 – June 7, 2019

Mission: Rockfish Recruitment & Ecosystem Assessment

Geographic Area: Central California Coast

Date: June 2-7, 2019

June 2, 2019 Game Plan and Trawling Line: 5 hauls in the Piedras Blancas Line near San Simeon, CA. Piedras Blancas is known for its Northern elephant seal colony, M. angustirostris. Hauls were conducted outside of the marine reserve and we did not encounter seals.

Catch Highlights: The night started off with excitement when Keith Sakuma brought in an Pacific electric ray, Torpedo californica, and we all got to see it up close before releasing.

Keith S and electric ray — Chief Scientist Keith Sakuma holding a Pacific electric ray, *Torpedo californica*

In Haul 3 we collected a pelagic octopus, Ocythoe tuberculata, shown below. Chromatophores in cephalapods, including squid, cuttlefish and octopus, are complex organs made up of both muscle and nerve and provide the ability for the animal to rapidly change its skin color in order to blend into the surrounding environment to avoid predation, communicate, or send a warning signal. It was impressive to watch the chromatophores at work as the pelagic octopus attempted to blend into the white background of his tank by turning white (see photos below) We released it back to the sea.

Pelagic octopus chromatophores — Pelagic octopus (*Ocythoe tuberculata*) with chromatophores expressing orange, purples and pinks. The beak is exposed here.

The differences in skin coloration of the five primary squid species we are catching including Boreal Squid, Blacktip Squid, Unknown Squid, Gonadus Squid, and Market Squid (see image below) are noteworthy. While living market squid exhibit brown, pink and purple skin color (see image below) the Chiroteuthis squid tentacle displays orange and red chromatophores (see image below).

Common squids in our catches. From top to bottom, Boreal Squid, Blacktip Squid, unknown species, Gonadus Squid, and Market Squid.

Living market squid exhibiting brown, pink and purple chromatophores.

Pink and purple chromatophores on the mantle of a market squid.

In Haul 4 we collected a Cranchia scabra, which Chief Scientist Keith Sakuma calls the “baseball squid” or glass squid whose body is covered with tubercles (brown spots on mantle in photo below). This animal attempted to hide from us by turning white, retracting its tentacles and inflating himself into a ball, somewhat resembling a baseball. After a few pictures, we released it back to the sea.

Cranchia scabra or "baseball squid" — *Cranchia scabra* or “baseball squid”

Another exciting deep-sea creature, the Pacific hatchet fish, Argyropelecus affinis, was collected in a bongo net deployed prior to CTD, for Dr. Kelly Goodwin’s eDNA research. The fish we collected below still has intact blue scales due to being well preserved in the bongo. The hatchet fish lives in mesopelagic zone down to 2000 m depths where the CTD sensors recorded a temperature of four degrees Celsius! Hatchet fish have upward facing eyes and mouths and swim up to the the epi-pelagic zone at night to feed on salps and krill.

Kelly conducted a quick surface bucket dip prior to CTD deployment in which we found a small (~2 inch) siphonophore, which I was very excited about since this was my first one to ever see in person! Siphonophores are colonial Cnidarians composed of individual animals called zooids. Moss Landing Graduate Student Kristin Saksa and I were able to confirm the identification of this beautiful creature as a siphonophore using an invertebrate field guide that Keith Sakuma brought on board. Perhaps due to the temperature change from being in the sea to being observed in a cell culture dish under the microscope, the siphonophore broke apart into its individual zooids right in front of my eyes. See before and after photos below.

Intact Siphonophore colony from bucket dip, note tip or “hat” at the bottom on the animal.

individual siphonophore zooids — Siphonophore individual zooids appear as semi circles consisting of small brown semi-circles.

Tonight I was also able to observe living salps that were pulled up in the bongo net and take a video. It was neat to see the salps pulsing.

Haul 5 was a massive haul full of pyrosomes, Pyrosoma atlanticum. Kristin Saksa volunteered to stir the bucket of pyrosomes (using her arms) so that we could obtain an accurate distribution of organisms for the initial volume count and analysis. As I video of this event (see stills from the video below), we were all laughing and realized that Kristin may be the only human on Earth who has ever stirred pyrosomes.

Kristin stirring pyrosomes — Kristin Saksa stirring a bucket full of *Pyrosoma atlanticum*

In haul 5 we were surprised to find a Giant 7-armed Atlantic octopus, or blob octopus. Keith Sakuma explained that the males have 7 arms as the fifth is a sex appendage whereas the female has 8 arms. After photographing this beautiful deep-sea octopus, we released him back to the sea.

blobtopus — Giant Seven-Armed Atlantic Octopus or “blob octopus”

June 3, 2019 Game Plan and Trawling Line: 5 hauls Outside Monterey Bay

Catch Highlights: Two of the hauls produced a lot of krill. The hauls had a high species density with a lot of myctophids, salps and blue lanternfish. Such hauls are time consuming to sort so as not to overlook something new and small. In one of the hauls we found a new-to-me myctophid called Nanobrachium. I dissected some of the fish and found that CA lanternfish and Northern anchovies were full of eggs, and their age/reproductive status was previously unknown.

We caught 2 young ocean sunfish, Mola mola. Both were immediately returned to the sea.

Kaila with young Mola mola — Scripps Graduate Student Kaila Pearson with a young ocean sunfish, *Mola mola*.

Keith and mola mola — LTJG Keith Hanson with a young ocean sunfish, *Mola mola*.

We found several species of deep sea dragonfish which we arrayed below on a ruler. Most of these fish are less than 6 inches long, no bigger than a pencil, but they are equipped with sharp fangs and are apex predators in their realm! Dragonfish have large bioluminescent photophore organs underneath their eyes (and sometimes lining their bodies) which produce light and are used to attract or deter prey and attract mates.

more dragonfishes — Longfin dragonfish, Tactostoma macropus, on left and a Pacific black dragon, Idiacanthus antrostomus, on right. Also in the photo are a krill (on the left of the dragonfish) and a Gonatus Squid (top left corner of photo).

Longfin dragonfish, *Tactostoma macropu*s, with large photo organ underneath the eye

We collected a stoplight loosejaw, Malacosteus niger, which can unhinge its jaw in order to consume large prey.

Face of stoplight loosejaw, *Malacosteus niger*.

June 4th: Davenport Line

The highlight of today was at 5:45 P.M. when team red hats went to the flying bridge for our workout and to hang out with Ornithologist Brian Hoover. There was a lot of Humpback whale activity. I counted around 20 spouts. We observed one whale that flapped its tail against the sea surface around 45 times in a row, perhaps communicating to nearby whales by generating pulses in the water or creating a visual cue. We saw several full breaches. We finished up the Davenport Line at 6:00 AM as the sea became rough. Thanks goodness for handrails in the shower.

The sorting team, aka Team Red Hats. From left: Kristin Saksa, Flora Cordoleani, Karah Nazor, Ily Iglesias, and Kaila Pearson.

June 5th: Outside of Tomales Bay

I woke up at 4PM and headed to the galley for dinner at 5PM. The boat was rocking so much that I became dizzy and knew that I would become sick if I tried to eat dinner, so I headed straight back to bed. Around 9PM the sea seemed to have calmed a bit, but I soon learned that it only felt calmer because the ship was traveling in the same direction as the swell at the moment but that we were about to turn around. Due to the rough conditions, the first haul inshore at Tomales Bay was delayed until midnight so the fish sorting team decided to watch “Mary Poppins Returns” in the galley. The talented chefs of the Reuben Lasker made the most amazing almond cookies today and, thankfully, temped me to eat again.

Catch Highlights: Haul 1 at station 165 was one of the easiest and most exciting catches of the survey so far because we collected a lot of jellyfish – my favorite! We counted 66 West Coast sea nettles, Chrysora fuscescens, seven Northern anchovies (7) and 24 market squid. I actually have a tattoo of West Coast sea nettle on my ankle. We placed the jellyfish flat on the lab bench and quickly measured their bell diameter before returning them to the sea. They did not sting us as most of the nematocysts were likely triggered during haul in. I removed a rhopalia, a sensory structure that lines the margin of the bell of Syphozoans (the “true” jellyfish). West Coast sea nettles have eight rhopalium which house the the ocelli (light sensing organ) and statolith (gravity sensing organ). A photomicrograph I took of the rhopalia under the dissecting microscope is below.

Karah measures sea nettle — Teacher at Sea Karah Nazor measuring a West Coast sea nettle *Chrysora fuscescens*.

Karah examines sea nettle — Karah Nazor examining a West Coast sea nettle, *Chrysora fuscescens*.

Kaila holds up sea nettle — Scripps graduate student Kaila Pearson examining a West Coast sea nettle, *Chrysora fuscescens*.

Kristin holds up a sea nettle — Moss Landing graduate student Kristin Saksa examining a West Coast sea nettle, *Chrysora fuscescens*.

Photomicrograph of the ocelli or light sensing organ in the rhopalia of a West Coast sea nettle, *Chrysora fuscescens*.

Haul 2 mostly consisted of Northern anchovies, 1 krill, a few moon jellyfish, Aurelia aurita, a few squid, which made for another very short and easy sort (see photo below). I study moon jellyfish in my lab back at McCallie High School, so I was curious to look inside of the stomach and reproductive organs of these wild jellyfish. Under the dissecting microscope, eggs were present and were purple in color (see photomicrograph below).

jellyfish eggs — Photomicrograph of purple eggs and clear gastric filaments of the moon jellyfish, *Aurelia aurita*

Kaila Pearson (left) and Karah Nazor and Keith Hanson sorting Haul 2.

Haul 3 had a lot of krill, young of year (YOY) Pacific hake, Merluccius productus, one large hake, and a few market squid. This sort was also super easy except for separating the small YOY Pacific hake from the krill.

Sorting of haul 3 which had a lot of krill and young of year (YOY) Pacific hake, Merluccius productus.

June 6th: Outside Farallones. On our final night, we conducted three hauls with very small harvests consisting of few organisms and low species density. One new to me fish in the final catch was a top smelt fish (see image below). These were the three easiest sorts of the survey. It was suggested by Keith Sakuma that the catches were small due to the stormy conditions.

A small catch from the last night June 6, 2019, with one West Coast Sea Nettle, a Gonatus squid, and two topsmelt silversides, *Atherinops affinis*.

Kristin with a topsmelt — Moss Landing graduate student Kristin Saksa with a topsmelt silverside, *Atherinops affinis*, from the final haul of the survey.

June 7, 2019: Return to San Francisco

Group photo at Golden Gate Bridge — In front of the Golden Gate Bridge at the conclusion of the cruise. From left: Brian Hoover, Kelly Goodwin, Ily Iglesias, Karah Nazor, Flora Cordoleani, Kristin Saksa, Lauren Valentino, and Jarrod Santora.

group photo at Marin Headlands — In front of the Marin Headlands at the conclusion of the cruise. From left: Ily Iglesias, Kristin Saksa, Flora Cordoleani, Kaila Pearson, Lauren Valentino, and Karah Nazor.

October 22, 2018

Andria Keene: The sun is setting on my adventure! October 21, 2018

NOAA Teacher at Sea

Andria Keene

Aboard NOAA Ship Oregon II

October 8 – 22, 2018

Mission: SEAMAP Fall Groundfish Survey

Geographic Area of Cruise: Gulf of Mexico

Date: October 21, 2018

Weather Data from the Bridge
Date: 2018/10/21
Time: 12:52
Latitude: 029 23.89 N
Longitude 094 14.260 W
Barometric Pressure 1022.22mbar
Air Temperature: 69 degrees F

The isness of things is well worth studying; but it is their whyness that makes life worth living.
– William Beebe

Last sunset — My last sunset aboard the Oregon II.

Science and Technology Log

Today is our last day at sea and we have currently completed 53 stations! At each station we send out the CTD. CTD stands for Conductivity, Temperature and Depth. However, this device measures much more than that. During this mission we are looking at 4 parameters: temperature, conductivity, dissolved oxygen and fluorescence which can be used to measure the productivity of an area based on photosynthetic organisms.

Once the CTD is deployed, it is held at the surface for three minutes. During this time, 4,320 scans are completed! However, this data, which is used to acclimate the system, is discarded from the information that is collected for this station.

CTD Collage — The crane lifts the CTD from the well deck and deploys it into the water.

Next, the CTD is slowly lowered through the water until it is about 1 meter from the bottom. In about 30 meters of water this round trip takes about 5 minutes during which the CTD conducts 241 scans every 10 seconds for a grand total of approximately 7,230 scans collected at each station.

CTD Graph — The computer readout of the data collected at one of the stations.

Our CTD scans have gathered the expected data but during the summer months the CTD has found areas of hypoxia off the coast of Louisiana and Texas.

Summer Hypoxia Zones — Data from CTD scans was used to create this map of hypoxic zones off the coast of Louisiana in summer of 2018.

Personal Log

The gloomy weather has made the last few days of the voyage tricky. Wind and rough seas have made sleeping and working difficult. Plus, I have missed my morning visits with dolphins at the bow of the ship due to the poor weather. But seeing the dark blue water and big waves has added to the adventure of the trip.

Dark clouds lifting — The gloom is lifting as a tanker passes in the distance.

We have had some interesting catches including one that weighed over 800 pounds and was mostly jellyfish. Some of the catches are filled with heavy mud while others a very clean. Some have lots of shells or debris. I am pleasantly surprised to see that even though I notice the occasional plastic bottle floating by, there has not been much human litter included in our catches. I am constantly amazed by the diversity in each haul. There are species that we see at just about every station and there are others that we have only seen once or twice during the whole trip.

Catch collage — A few of the most unique catches.

I am thrilled to have had the experience of being a NOAA Teacher at Sea and I am excited to bring what I have learned back to the classroom to share with my students.

Challenge Question:

Bonus points for the first student in each class to send me the correct answer!

These are Calico Crabs, but this little one has something growing on it? What is it?

Did you know…

That you can tell the gender of a flat fish by holding it up to the light?

Flatfish collage — The image on the top is a female and the one of the bottom is the male. Can you tell the difference?

Today’s Shout Out!

Kudos to all of my students who followed along, answered the challenge questions, played species BINGO, and plotted my course! You made this adventure even more enjoyable! See you soon 🙂

July 17, 2017July 17, 2017

Anna Levy: First Day of Fishing! July 12, 2017

NOAA Teacher at Sea

Anna Levy

Aboard NOAA Ship Oregon II

July 10 – 20, 2017

Mission: Groundfish Survey

Geographic Area of Cruise: Gulf of Mexico

Date: July 12, 2017

Weather Data from the Bridge

We’re traveling through some mild rainstorms. Nothing extreme, but we do feel a little more side to side rocking motion in the boat (which makes me feel sleepy!)

Latitude: 29 degrees, 56.2 minutes North

Longitude: 86 degrees, 20.6 minutes West

Air temp: 24.7 degrees Celsius

Water temp: 30.1 degrees Celsius

Wind direction: light and variable

Wind speed: light and variable

Wave height: 1 foot (about 0.3 meters)

Sky: overcast with light rain

Science and Technology Log

Today I completed my first shift on the science team and we surveyed 3 complete stations. At each station, we carried out a multi-step protocol (or procedure). Here are the steps:

The Depth Contour Output graph displays data collected from one station.

Before we begin fishing, the ship conducts a transect (or cross-section) of the survey area, using multiple pieces of equipment to observe the ocean floor. This tells us if it is safe (for both ship operations and for fragile coral that may exist) to trawl here. If a coral reef or other large obstacle was present, we would see significant variation in the depth of the ocean floor. This “depth contour output” graph shows the data we collected at one station. How deep is the water at this station? Is it safe to trawl here?

The CTD collects information about water chemistry

We also use a collection of instruments called a “CTD” to collect information about the chemistry of water itself at different depths. This information is called the water’s “profile.” For fisheries studies, we are most interested in the amount of dissolved oxygen and the temperature at different depths. Why might this information be relevant for understanding the health of fish populations?

We also measure the water color using the Forel-Ule color scale by matching it to the samples shown in this photo. This gives scientists an indication of the amount of particulates, chlorophyll, and nutrients are in the water.

Once we determine it is safe to trawl, the ship returns to the starting location. We will trawl along the same path that we observed. Here’s the trawl net before it is lowered into the water. It will be pulled just along the bottom of the survey area, using tickler chains to agitate the ocean floor for benthic organisms for 30 minutes, and collecting whatever crosses its path!

Once the trawl is finished, the deck crew uses a large crane to pull the trawl on board. We all help to empty the net and place everything into baskets. Most of what we catch are biological organisms, but small amounts of non-living material (like shells, dead coral, and even trash) come up as well.

We then bring the baskets into the wet lab.

Baskets are emptied into a long trough with a conveyor belt

We dump the baskets into a long metal trough that has a conveyor belt at the bottom.

The catch is sorted into baskets by species

Next we sort the catch. Each species gets its own basket and we count the number of individuals for each species.

Then, it’s time for the tough part (for me at least) – every organism has to be identified by its scientific name. That’s a lot of Latin! Fortunately, Andre and the senior scientists are very patient and happy to help those of us who are new. It’s amazing how many species these experienced scientists recognize off the top of their heads.

We also have many field guides, which are books containing photos and descriptions of species, to help us.

For each species, we record the total number of individuals and total mass

We are interested in how much of each species are present, so we record both the total number of individuals and total mass of each species.

TAS Anna Levy measures the length of a flatfish using the Limnoterra Board

We also measure the length and mass of a sample of individuals. A handy device called a Limnoterra Electronic Measuring Board makes this process easy. We place the mouth of the fish on one end of this board and then touch its tail fin with a pen-like magnetic wand. The board then automatically sends the fish’s length to the computer to be recorded. We use an electronic balance that is also connected to the computer to measure and record mass.

A computer screen displays FSCS software

All of the information is recorded in a database, using software called FSCS (pronounced “fiscus”).

Many of the specimens we collect are saved for use in further research on land. Scientists at NOAA and other research institutions can request that we “bag and tag” species that they want. Those samples are then frozen and given to the scientists when we return to shore.

Any organisms or other material that remains is returned to the sea, where it can be eaten or continue its natural cycle through the ecosystem. The conveyor belt, conveniently, travels to a chute that empties back into the ocean. Now all that’s left is to clean the lab and wait for the process to begin again at the next station!

Our goal is to complete this process 48 times, at the 48 remaining stations, while at sea. 3 down, 45 to go!

Personal Log

This work has real highs and lows for me, personally. There are dramatic, hold your breath, moments like when equipment is lifted off the deck with cranes and lowered into the water. There is the excitement of anticipating what data or species we will find. My favorite moment is when we dump the buckets and all of the different species become visible. I’m amazed at the diversity and beauty of organisms that we continue to see. It reminds me of all of the stereotypical “under the sea” images you might see in a Disney movie.

The more challenging part is the pace of the work. Sometimes there are many different things going on, so it’s easy to keep busy and focus on learning new things, so time passes quickly. Other times, though, things get repetitive. For example, once we start entering all of the data about the individual fish, one person calls out the length and mass of a fish, while the other enters it into the computer – over and over until we’ve worked through all of the fish.

… but sometimes the work even stops altogether, especially when whether interferes.

Sometimes, the work even stops altogether, especially when the weather interferes. There have been mild rainstorms coming and going continually. It is not safe to have people on deck to deploy the CTD and trawling equipment when there is lightning in the area, so there is nothing for the science team to do but wait during these times.

Because the pace of the work is constantly changing, it’s difficult to get into a groove, so I found myself getting really tired at the end of the shift. However, an important part of collecting data out in the field is being flexible and adapting to the surroundings. There is a lot to accomplish in a limited amount of time so I keep reminding myself to focus on the work and do my best to contribute!

Did You Know?

When working at sea, scientists must use special balances that are able to compensate for the movement of the ship in order to get accurate measurements of mass.

To ensure that we are accurately identifying species, we save 1 individual from each species caught at a randomly selected station. We will freeze those individuals and take them back to NOAA’s lab in Pascagoula, where other scientists will confirm that we identified the species correctly!

Questions to Consider:

Review: Look at the “depth contour output” graph above: How deep is the water at this station? Is it safe to trawl here?

Research: What does “CTD” stand for?

Research: For fisheries studies, we are most interested in the amount of dissolved oxygen and the temperature at different depths. Why might this information be relevant for understanding the health of fish populations?

Reflect: Why might scientists decide to use three different pieces of equipment to collect the same data about the ocean floor? And, why might they have several different scientists independently identify the species name of the same individuals?

June 30, 2017June 30, 2017

Dawn White: Finally Fishing! June 27, 2017

NOAA Teacher at Sea

Dawn White

Aboard NOAA Ship Reuben Lasker

June 19 – July 1, 2017

Mission: West Coast Sardine Survey

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

Date: June 27, 2017

Weather Data from the Bridge

Date: June 27, 2017                                                         Wind Speed: 28.9 kts with gusts
Time: 9:15 p.m.                                                                 Latitude: 4828.20N
Temperature: 13.4^oC                                                      Longitude: 12634.66W

Science and Technology Log

White_Lasker route 6-27 — The red line indicates the route of NOAA Ship *Reuben Lasker* transiting along the coast of Vancouver Island

We finally reached the tip of Vancouver Island on Sunday evening, June 25. It would be our first night of fishing. The red line indicates the route taken by the Reuben Lasker as we transited along the coast to the northernmost tip of the island. The blue lines indicate the path to be taken for regular interval acoustic monitoring for schools of fish. Based on the acoustics results, a decision would be made as to where the fishing would occur at night.

White_deploying net — Crew deploying the fishing net

The photo at left shows the crew completing the deployment of the fishing net. You can see the large winch that will release and retrieve the main body of the net. The net will be set out for about 45 minutes. During this time there are many variables that will be monitored. Sensors attached to the net will collect data on time spent at each depth. Other factors being monitored include temperature, wind speed, swell size, and lat/long of trawl. In addition, there are four water-activated “pingers” attached to the net that emit sounds at frequencies known to disturb larger mammals in an effort to reduce accidental captures.

Once the net has been retrieved, the scientists collect the catch in large baskets and begin the process of weighing and sorting. The first night’s catch was primarily made up of a very unique colonial type of organism called a pyrosome. The side nets and codend (mesh covered end of the main net where most of the catch is collected) were packed with these the first couple of trawls.

White_many pyrosomes — Many pyrosomes were mixed in with the catch.

You can see many pyrosomes mixed in with the rest of the catch here. They are the pink colored cylindrical organisms. They have been increasing in population over the past couple of years as well as appearing further north than ever observed before. A nice overview of the pyrosome influx and volumes observed was recently reported in an article published by Environment entitled “Jellied sea creatures confound scientists, fishermen on U.S. Pacific Coast”. You can review the article here.

The trawl net being used was part of the research project, as it possessed modifications aimed at capturing and quantifying organisms that made it through an apparatus called the extruder door. The purpose for this opening is to allow for larger mammals and non-target organisms to pass through the net relatively unharmed should they get caught. Two additional pocket nets had been added to the main net for the specific purpose of monitoring what made it through the mesh.

This far north, the researchers were expecting to find mostly juvenile herring and salmon. On our second night of fishing we actually had several species of fish and other marine animalia to i.d. The amount and type of data collected depended on the species of organism. In some cases, we collected just the mass of the group of organisms as a whole. For other species, we collected mass, lengths, presence/absence of an adipose fin, DNA samples from a fin clip, and more. Certain species were tagged, bagged, and frozen for further study in a land-based lab. It’s so interesting to see the variety we pull out of the net each trawl!

Some of the species collected can be seen below:

Extension question for my students reading this:

What traits could you use to differentiate between the juvenile salmon and Pacific herring?

Personal Log:

White_scientists collecting data — Here are some of the scientists making sure the correct data is collected and recorded from one of our catches.

White_here i am in yellow — Here I am (in yellow) with some of the scientists (L to R: Emily, Amy, and Angela) getting ready to receive the evening’s catch.

First trawl starts as close to sunset as possible, which for this latitude has been somewhere between 9:30-10:00 p.m. There is always this air of anticipation as we wait for the net to be emptied. It has been enlightening to work with the science staff as they evaluate each sample. The number of reference sheets and data recording forms is incredible. It seems like you would need to take a course in data management just to ensure you were familiar enough with the requirements to not overlook some detail of importance.

The photo of the group above was taken about 11:00 p.m. I was worried initially that I would not be able to flip my sleep schedule to match the work schedule, but it has been much more doable than I thought it would be. Our staterooms are dark and quiet, so going to bed in the morning really doesn’t feel any different that at night. Thanks to the extensive movie collection and my ability to keep downloading books to read on Kindle, I have had plenty of filler for downtime and that “reading before bed” I always do.

Time to go to work…..

Did You Know?

There are 36 species of dolphin worldwide, including 4 species of river dolphins. Quite a few of the Common Bottlenose Dolphin followed the ship out of the harbor in San Diego, riding along on the wake produced by the ship. On the way up the coast of California I saw a couple of Dall’s Porpoises (not in the dolphin family, but quite similar in appearance). Then as we traveled south along Victoria Island there were a couple of Pacific White-Sided dolphins enjoying games along-side the ship. It is so exciting to see these animals out in their native habitat!

Every night before the ship drops the fishing net, a member of the science team is sent to the bridge to perform a 30-minute mammal watch. The surrounding waters are observed closely for any signs of these and other larger species. The investigators do their best to ensure that only the small fish species intended for capture are what enters the net. Should there be a sighting, the ship moves on another 5 miles in an effort to avoid any accidental captures. The scientists and crew work very hard to minimize the impact of their studies on the surrounding ecosystems.

June 12, 2017

David Amidon: Back to Work, June 10, 2017

NOAA Teacher at Sea

David Amidon

Aboard NOAA Ship Reuben Lasker

June 2 – 13, 2017

Mission: Pelagic Juvenile Rockfish Recruitment and Ecosystem Assessment Survey

Geographic Area of Cruise: Pacific Ocean off the California Coast

Date: June 10, 2017

Weather Data:

Latitude: 33 degrees, 43 min North; Longitude: 119 degrees, 32 min West

Air Temp: 16.7 C Water Temp: 16.9 C Wind Speed: 27 knots

Science Log

After our quick stop into port, we were back to the sorting last night.

I will take you though a step-by-step account of the sort.

A science crew member reports to the Bridge for the 30 min Marine Mammal Watch. The fishermen ready the net.
We arrive at the Station. Science crew goes on deck for the Outdoor Marine Mammal Watch. The fishermen put the net in the ocean and begin trawling.
After a 15 minute trawl, the net is hauled in and the Marine Mammal Watch ends.
The crew brings the sample collected in a bucket into the Science Lab.
Based on the size of the catch and the organisms present, the crew determines an appropriate sample size. This time we went with a 250 ml sample as there were a TON of small pyrosomes.

Determining the volume of the total catch

Selecting a mixed subsample

Our 250ml sample
We sort based on visual identification.

Separating the first subset

We found pyrosomes, some anchovy & market squid, as well as flat fish and salps.
People sorting will call out their counts of each species and record the numbers collected.
Isolate a sample of krill to be specifically analyzed. They determine the species in the sample and number of each.

Collecting the krill sample

A krill under the microscope
Determine a second sample size to analyze. At each subsequent sample, we will stop counting specific organisms, such as tonight when we stopped counting the pyrosomes because we had enough data to extrapolate a value for the number collected. Then we stopped counting anchovies, etc. until we are just looking for outliers, or creatures in such low abundance an estimate would not be acceptable.

Selection from larger subsample

Organized sort

Repeat the steps until we have gone through the entire catch.
Afterwards, information is logged into the database and representative samples are measured and recorded.
Sorting the catch
The last step is to prepare samples for onshore analysis. Many labs have a standing request if samples are available, such as 5 Hake or a sample of anchovies. Specifically, the juvenile rockfish will undergo DNA analysis as well as having otoliths removed for further analysis. Basically, fish grow these little ear bones with rings like a tree. The more rings, the longer a fish has been alive. Therefore, the researchers can determine the age and growth rates of the fish based on these features.

Removing otoliths from a rockfish

A rockfish otolithe under the microscope

An Argonaut – basically an octopus with a shell

A Pyrosome under the microscope. This is really a COLONIAL organism, not truly multicellular.

Personal Log

Thursday, June 8th

We arrived in port today, so nothing on the science end to report. As we conducted the trawls the night before, I was still on the night schedule and missed out on a chance to explore San Diego. However, we did go to dinner with the other science personnel that work the daytime shifts, which was nice.

Friday, June 9th

The repairs went well and we returned to the ocean. We arrived at a station just after midnight and worked on 3 trawls. Waves started picking up during the shift. It is supposed to be windy again, which means the waves action will increase too.

Saturday, June 10th

Did I mention the winds were going to pick up? Wow. They were right – and tomorrow won’t be any better. I put the patch back on, which is unfortunate because my major side effect is that it really makes me tired. Or it could be that I have a tendency to visit the Flying Bridge to watch the sun come up.

Tonight we caught adult anchovies – and a lot of them. We ended saving a lot of the catch for other labs and for bait.

The night’s 1st catch 6/10

Starting the sort – check out those adult anchovies!

Adult anchovies vs YOY or Young of the Year

DID YOU KNOW?

At night, the officers piloting the ship keep all the lights off on the bridge. All displays are illuminated with red lights. In this way, the people on the bridge will keep their eyes adjusted to the dark and they will be better prepared to spot potential problems on the water.

At night, bridge displays are illuminated with only red light, which keeps officers’ eyes better adjusted to the dark.