otoliths – Page 4 – NOAA Teacher at Sea Blog

June 18, 2012August 11, 2021

Lesley Urasky: Setting Sail from St. Croix, June 16, 2012

NOAA Teacher at Sea
Lesley Urasky
Aboard the NOAA Ship Pisces
June 16 – June 29, 2012

Mission: Caribbean Reef Fish Survey
Geographical area of cruise: St. Croix, U.S. Virgin Islands
Date: Saturday, June 16, 2012

Location:
Latitude: 17.6395
Longitude: -64.8277

Weather Data from the Bridge:
Air Temperature: 29°C (84°F)
Wind Speed: 15.76 knots (18.1 mph)
Relative Humidity: 79%
Barometric Pressure: 1,012.7 mb
Surface Water Temperature: 29°C (84°F)

Personal Log

My trip to meet the Pisces and become a Teacher at Sea was a two-day process. I traveled from my home in Sinclair, Wyoming to Denver, Colorado to catch the first of three flights. The first flight was from Denver to Dallas/Ft. Worth International Airport; after a two-hour layover, I then flew to Miami. Originally, I was to travel the entire way in one day. However, I didn’t want to arrive in St. Croix at 10:00 p.m. and have to make my way to the pier, pass through security, board the ship, find my stateroom, and hopefully meet some of the crew and scientists late at night. Instead, I spent the night in Miami and flew to St. Croix the next morning.

Trip to St. Croix from Sinclair, Wyoming — Google Earth view of my trip to St. Croix.

Once I landed at the Frederiksted Airport on St. Croix, I took a taxi to the cruise ship pier. The taxi driver was very concerned about taking me there, because no cruise ships were docked; he was doubtful that any ship was there. After convincing him that a NOAA ship was indeed docked, he moved aside the sugar cane in the back, loaded my bags, and took me to the pier. Breaking my trip into two pieces turned out to be the best plan because once I got to the security gate, there was no approved members list at security and they wouldn’t accept my travel document. They called the ship and the Commanding Officer (CO) came down the pier to meet me at the gate and escort me to the ship. After a quick tour of the ship, I took some time to settle into the stateroom I’m sharing with the Operations Officer, Kelly Shill. The rest of the afternoon was spent exploring Frederiksted.

The NOAA ship Pisces — The Pisces viewed from Frederiksted, St. Croix

On Friday, June 15th, I went to Christiansted with some of the ship’s crew members. Kelly Schill, Operations Officer; Chris Zacharias, Junior Engineer; Peter Langlois, 3rd Mate; and I went shopping for souvenirs, had lunch, and fed the resident school of tarpon outside of Fort Christian Brew Pub. Later that evening, we went to a beachside restaurant and watched a performance by some modern dance fire dancers.

Tarpon waiting to be fed in the Christiansted harbor. — Hungry tarpon waiting for tidbits.

Today we left port and embarked on the third Leg of the Caribbean Reef Fish Survey. The first leg was when the Pisces traveled from Pascagoula, Mississippi to San Juan, Puerto Rico; here the ship picked up the scientific crew. The second leg was from San Juan, Puerto Rico to St. Croix; during this time period, they collected data about the ocean and the fish along the reef system. I joined the scientists and crew of the Pisces at Frederiksted, St. Croix in the U.S. Virgin Islands. The Pisces was in port at St. Croix for three days for personnel change, resupply of the galley, and to give the crew a rest. During this leg, we will be traveling back to San Juan, Puerto Rico taking samples around St. Croix and St Thomas islands. In addition to the reef fish survey, the Pisces will be deploying the base (anchor and chain) for another buoy to collect oceanographic data 3 nautical miles (nm) south of Saba, which is located between St. Croix and St. Thomas. The University of Virgin Islands is working in conjunction with NOAA to accomplish this goal. Once back in San Juan, the scientists will leave the ship, returning home with the data. On the fourth leg, the Pisces will return to Mayport, Florida, retrieving a buoy that is adrift along the way. Commander Fischel is kindly allowing me to remain aboard during the cruise back to port!

Science and Technology Log

Here is a quick overview of all equipment the survey will use to collect data. There is an array of four video cameras that is baited with frozen squid. The array is lowered over the side of the ship at each sampling site, and allowed to rest on the bottom for 40 minutes. The cameras cannot be deployed during the night because there are no lights on the array. Therefore, viewing is dependent upon the availability of sunlight penetrating the water column. Because of the need for natural light, the cameras are only used during daylight hours; the array cannot be deployed earlier than one hour after sunrise and must be retrieved from the bottom of the continental shelf or shelf edge one hour before sunset.

After the camera array is deployed, a cluster of instruments called a CTD is lowered to collect data on the ocean environment. CTD is an acronym for Conductivity, Temperature, and Depth. Conductivity is used to determine the salinity (the amount of salts dissolved in the water). Water conducts electricity (this is why you shouldn’t use electrical appliances while in or around water, and why the lifeguard tells you to get out of the pool during a thunderstorm). As the salinity increases, conductivity increases. Temperature is a very straight forward measurement. I’m sure you’ve measured the temperature of several different things ranging from air temperature (to see how hot it is outside) to the internal temperature of a roasting chicken. These measurements are related to specific depths within the water column. The depth the instrument is at in the ocean is calculated from measuring the hydrostatic pressure (how much pressure the overlying water exerts on the instrument). The CTD instrumentation cluster collects huge amounts of data – 8 measurements per second! These are averaged and compressed into “bins” covering 1 meter segments.

CTD and Camera array waiting deployment — The CTD and camera array waiting deployment.

In addition, the instrument cluster also measures the amount of oxygen dissolved (DO) in the water column. As you probably already know, most organisms require oxygen to live (carry out cellular respiration). The amount of oxygen dissolved in the water is directly correlated to how much life the water can support. More oxygen = more life. When water is warmer, it loses its ability to “hold onto” oxygen; cold water will contain more dissolved oxygen. This is one reason why climate change and warming aquatic environments are of great concern.

Deploying the camera array — Victor, Joey, and Joe deploying the camera array

After both the camera array and CTD have been deployed and retrieved, the final step at each site is to collect fish through the use of bandit reels located at three sites on the ship. All three are located on the starboard (right hand) side of the ship. Reel #1 is starboard (S), Reel #2 is starboard aft (SA), and Reel #3 is starboard stern (SS) at the back of the ship. Reel #3 is where I helped the attempts to collect fish. Each bandit reel has ten hooks of the same size (8/0, 11/0, and 15/0) attached to a 300-lb test monofilament. Each of the hook sizes are rotated around the stations throughout the day. These hooks are baited with slices of frozen Atlantic mackerel. A 10 pound weight is attached to the end of the line, the baited hooks attached, and the line let out until it hits bottom. Then, a float is attached and the line is left for five minutes before being reeled back in.

Any fish that are caught are identified and have their length and mass measured. Afterwards, the fish’s otoliths are removed and it is opened to determine its gender and have its reproductive stage assessed. More on the fish specifics to come!

August 29, 2011April 28, 2021

Marian Wagner: From Fishing to Dissecting in the Wet Lab, August 22, 2011

NOAA Teacher at Sea
Marian Wagner
Aboard R/V Savannah
August 16 — 26, 2011

Mission: Reef Fish Survey
Geographical Area: Atlantic Ocean (Off the Georgia and Florida Coasts)
Date: Monday, August 22, 2011

Science Team on R/V Savannah Aug 16-26, 2011: Back row: Chief Scientist Warren Mitchell, Christina Schobernd, Katie Rowe, Mike Burton. Front row: Shelly Falk, Stephen Long, Sarah Goldman, Marian Wagner, David Berrane.

Weather Data from the Bridge (the wheelhouse, where the controls of the ship are)
S-SW Wind at 15 knots
(This means wind is travelling 15 nautical miles per hour, 1.15 statute miles = 1 nautical mile)
Sea depth today ranged from 45 meters to 74 meters
Seas 3-4 feet in the morning, 2-3 feet in the evening (measure of the height of the back of the waves, lower the number = calmer seas and steadier boat)

Science and Technology Log

In my last blog, I explained what I am doing on the first half of my shift (noon to around 6:00pm/dinnertime) and how we conduct our research on the aft deck of the boat: we drop chevron traps to the ocean floor with cameras attached and then pick up the traps with fish sample collections. The fish we trap and the cameras recording the activity around the traps help us estimate the fish populations. We finish up this segment of our work on the deck of the boat by recording this data in a systematic data collection sheet called “Length Frequency”. If we didn’t record the data the same way every time, it would be impossible to compare the thousands of samples in the past and into the future and understand what is happening to the populations of fish over time.

Here is a picture of us recording the weight and length of the fish and the frequency (how many we caught) in a systematic way, always keeping track of where the fish were caught as well. Because we catch large numbers of certain fish species (such as Vermillion Snapper, Red Porgy, Gray triggerfish, and Black Sea Bass), we do not keep all of them for further research. When recording/reporting “toss” or keep” got monotonous, I found ways to communicate creatively—how many words can you think of that rhyme with “toss” and “keep”? I got 11 for toss and 16 for keep. David, Katie, and Stephen were such sports for going along with my silly games!

After this point in the day, the fish are in bags and put on ice, and we wash up for dinner.

After dinner, our work moves into the wet lab, where we prepare biological samples for further research. For the rest of this log section I describe more about how and why we
use the biological samples.

Dissecting Vermillion — Dissecting vermillion snapper in wet lab, in search of otoliths and gonads.

We use the biological samples to obtain and report important biological measures such as age, length, weight, feeding habits, and genetics. In order to know specific ages of the fish, we take out a small bone in the fish called the OTOLITH, which is located in the inner ear. An otolith is a reliable source to obtain the age of a fish. They show age in rings similar to how trees show their age in their growth rings. We also take the GONADS from the fish to give important information about reproductive development. Here is a picture of me dissecting a vermillion snapper and taking out the otolith (right hand) and gonads (left hand) to send to the lab back in Beaufort, North Carolina, where scientists work.

Gray Triggerfish — Here I just reeled in a gray triggerfish, one of our target species for hook and line catch.

Sometimes after dinner we had time to fish with hook and line in the stunning sunset. This method of catching fish provided us with fish samples to study that did not have stomachs full of bait like the rest of our fish samples caught in traps. We did this so we could study their stomach contents and learn about what they are eating and get information about the ecosystem they are dependent upon. We were targeting vermillion snapper and gray triggerfish, fish that are known to really gorge on bait in the traps. Sarah was dissecting the stomach of scamp grouper and found an octopus beak!

Sarah Dissecting Scamp Grouper — Sarah dissecting stomach of scamp grouper and finds octopus beak!

When Sarah was dissecting the stomach of a scamp grouper, she found an octopus beak, the last part of the octopus to be digested. Exciting find!!

Hook and Line Teamwork — When fishing becomes chaotic, teamwork is key.

Here is one of my favorite pictures of all, captured during one of our hook and line battles, and a testament to the incredible teamwork of the scientists and crewmen. How many people does it take to catch a fish? Here, 5 of us were working on the same task. Lines from 4 reels were tied up from a strong fish swimming in circles, and it took an intense team effort to unravel them in a critical moment. Success was sweetly earned.

Click here for more info on the fish we are studying for stock assessments.

Personal Log

I’m on a boat! This phrase has been repeated many times and it captures my enthusiastic awe (with a touch of humor) that I have had many privileges, and the fortune to be around some remarkable people, day in and day out. I took the opportunity to interview a few of them so I could share it here. (Next blog: Interview with Captain Raymond Sweatte)

Interview with Richard Huguley, engineer

Marian: When you were a kid, would you have imagined yourself here now?

Richard: Yes. In Mobile, Alabama, where I grew up, I played with wooden boats, making them go up and down the creek, and spent time catching crawfish. I could see this as where I’d be.

M: How often did you play outside?

Richard: From sun-up to sun-down. I skipped out to the woods all day some days. I was never afraid to be in the woods. I played with snakes, frogs, had a baby pet squirrel I kept in my pocket. It poked its head out to eat, and then crawled back into my pocket.

M: How did you become prepared for work as an engineer on a boat?

Richard: I have worked in all different fields required of an engineer: electrical, metal manufacturing-welding, automotive, building race cars and motor cycles, etc. I always had the interest to take a challenge someone else wouldn’t take—not a challenge that just required physical strength, but more of intellectual puzzle. It takes lots of time. I took the time to figure the challenges out. I can visualize math. My dyslexia is a strength I use to my advantage. I see people struggling with something, and it’s like I see it from the opposite end. I do it without thinking about it. Jigsaw puzzles are good for this kind of challenge. It would be good for your students to try doing a jigsaw puzzle with the pieces upside down so they build the puzzle from the angles of the edges.

Thank you, Richard, for taking the time to talk and share your stories and the many skills you taught me. You are one-of-a-kind and I hope you can come visit my classroom someday!

Interview with Katie Rowe, scientist and scuba diver/instructor

Marian: What do you like about working in a lab?

Katie: Lab work is about exploration, you don’t know entirely what you’ll find. We’re looking for otoliths, etc, but there is a possibility to find anything!

M: What makes the best partnerships in the lab?

Katie: I like working with people who are organized and efficient, people who can interpret and know what needs to be done next. It takes an organized system for people to work like this, like we work here. The system works well here so everyone knows what they are doing, and what happens next so we can all step in and do what needs to be done.

M: What’s your favorite animal?

Katie: Bull shark, Carcharhinus leucas, because they are adaptable. They can survive in fresh water. In Nicaragua, one was found in fresh water going after fish to eat, and they thought it was a new species, but then realized it was the bull shark. They have the highest testosterone of any animal in the world, so they are bad-tempered, but I still love them. I named my cat Leucas after the bull shark’s Latin name.

Thanks Katie! It was great to work with you day in and day out! You are a tough gal and make an excellent partner, very organized and efficient!

Pulling Up Buoys with Grappling Hook — Tossing grappling hook to "catch" buoys attached to fish traps.

Fun extra: How do we retrieve the buoys and pull up the fish traps? I got to try my hand at this new sport, the grapple hook toss. I am so grateful to have had the chance to try my hand at so many different roles. Thanks for the opportunity!

August 22, 2011March 12, 2021

Jennifer Goldner: Still Learning! August 22, 2011

NOAA Teacher at Sea
Jennifer Goldner
Aboard NOAA Ship Oregon II (NOAA Ship Tracker)
August 11 — August 24, 2011

Mission: Shark Longline Survey
Geographical Area: Southern Atlantic/Gulf of Mexico
Date: August 22, 2011

Weather Data from the Bridge
Latitude: 27.56 N
Longitude: 83.73 W
Wind Speed: 5.95 kts
Surface Water Temperature: 30.50 C
Air Temperature: 31.60 C
Relative Humidity: 66.00%

Science and Technology Log

Okay, so I admit, I can’t learn enough. I just THOUGHT I was doing my last post, but I have to share with you some more information I learned toward the end of our journey. So if you want to learn some “cool facts,” today’s post is for you!

Cool Fact #1: Sargassum– This is a type of seaweed we saw in the ocean today alongside the ship. It mats together in large clumps and serves as a refuge for larval fish. It also is a type of “floating community” with lots of fish, such as mahi mahi, congregating around it. Newly hatched sea turtles find refuge in sargassum.

Sargassum off the starboard side of NOAA Ship Oregon II

Cool Fact #2: Shark skin samples and fin clips — All week long I have seen shark skin samples and fin clips taken, but today I found out from two of the scientists on our survey, Dr. Trey Driggers and Adam Pollack, what is done with these. The skin sample is done so the shark can be identified down to the species. For example, there are 3 species of smooth dogfish in the Gulf of Mexico. They all look the same externally. Keep in mind, the smooth dogfish shares the same genus (Mustelus), but the species differs. One of the ways to tell them apart is to look at their skin sample under a microscope. For this reason, every shark that is caught has a small sample of skin taken that is placed in alcohol for preservation.

When it gets to the lab, the scientist looks at the dermal denticles (scales) under a microscope. If the denticle has 1 point, its species is either canis (common name– smooth dogfish) or norrisi (common name–Florida smooth dogfish). If it has 3 points, its species is sinusmexicanus (common name- Gulf smooth dogfish).

The fin clip is collected and archived and later a DNA analysis is performed. They are compared to fish of the Gulf of Mexico to tell if they are genetically different or similar. This information is used for stock management.

Cool Fact #3: Otoliths– I have been assisting the scientists this week in getting the otoliths from various fish, such as red grouper, yellowedge grouper, and blueline tilefish. Today I got to take the otoliths out myself. By “myself,” I mean with the help of skilled scientist, Adam! It was neat! So what are otoliths? They are the ear bones of fish. They tell the age of the fish, much like the annual rings of a tree trunk do. These are collected and put in an envelope with the identification number in order to be observed under a microscope in the lab.

Removing the otoliths- Thanks to Adam, Scientist, for teaching me how to do this!

Personal Log

Last night after our shift ended at midnight, by the light of the moon we watched a pod of about 25 dolphins chase flying fish and play in the wake of the boat. I sure will miss all the sights the sea has to offer. I will especially miss the people.

I mentioned in an earlier post that NOAA Ship Oregon II is like a city. It has everything needed on board to run smoothly. There are people with numerous kinds of backgrounds. Each and every one of these individuals is needed in order to successfully complete a NOAA mission, whatever it may be.

So now I’m talking to you kids. Have you ever thought about what you want to be or do when you grow up? How about starting now? How about you adults, have you ever thought about trying to do something new and exciting? I have a question for you (and I would like for you to put your answer in the poll): If you could choose any job on this ship, what would it be?

If you will notice from my posts, I did not just cover the science end of this ship. There are so many other careers going on to make these surveys work. It’s a team effort. Under the leadership of Cap Nelson, that’s exactly what you have here on NOAA Ship, Oregon II: a team effort. And that’s what makes this ship a model for any team to follow.

July 28, 2011April 28, 2021

Walter Charuba: Red Skies at Night: July 21st, 2011

NOAA Teacher at Sea
Walter Charuba
Aboard R/V Savannah
July 18 — 29, 2011

Mission: Reef Fish Survey
Geographical Area: Southeast Atlantic Ocean
Date: July 21, 2011

Science and Technology Log

There is an old sailor’s proverb: “Red Sky at night, it will be bright” or “sailors take flight“ or something like that. I just know that I live by this saying and it has caused many a captain to throw away their weather charts. There was a beautiful red sunset last night and I stood at the bow or stern (I am down to two boat locations now) in complete admiration. However, when I started my shift in the morning there was a front moving in with rain clouds and lightning. I must admit I have been pretty calm most of the trip and this has not been due to the Dramamine. Seeing these clouds caused my imagination to get the better part of me, which of course would be the part that includes my brain. I had images of “The Great Wave” by Hokausai racing in my head. This outlook was ridiculous because there weren’t even white caps on the waves. The storm never hit us and the day turned out to be excellent.

NOAA Teacher at Sea Dolphins Night BesT — Dolphins chasing flying fish at night

Another reason last night was special was because I was able to view some dolphins at a very close distance. First Mate, Michael Richter, made it quite clear that no one was supposed to walk around the boat alone at night, especially the dark upper deck , and especially on the railings. So after daylight, we are limited to the lighted lower deck. As I was reviewing my constellations, the light seemed to attract these flying fishes. I do not know if this is true, because correlation isn’t always causation, but it looked true. As I was staring at the flying fishes, a large splash startled everyone. It was a spotted dolphin and a calf jumping for the flying fishes. The dolphins jumped around for about twenty minutes until we took off to our next destination. It was kind of like our own little Sea World, except natural. It was a perfect way to end the night.

NOAA Teacher at Sea Trap Collection — Here I am (right) preparing to help with the trap collection

Morning was the time to not only see, but capture, new creatures. My last blog described the deployment of traps, but now I will write about the retrieval of traps. Science Watch Chief, David Berrane termed this “action time.” The two flotation buoys we drop are significant because, after “soaking” a trap for 90 minutes, the boat returns to these devices and a crew member has to throw a grappling hook at a line between the buoys. We then quickly pull the buoys in next to the boat. The buoys are lifted up, the line is connected to a “hauler,” and a trap is pulled on board. This may sound simple but it is actually a five person task. The task is very intense and focused because people may trip over the buoys or ropes, or the trap’s line can snap due to weight or current. Hopefully the trap will be filled with fish and the cameras will record useful data from depths ranging from 25 to 83 meters. As soon as the trap is brought on board, the fish are collected and the cameras are disconnected.

NOAA Teacher at Sea Cameras — The cameras used on the fish traps

The video survey of the reef is just as important as capturing fish, as cameras can assess the population of species that do not go in traps. Zeb Schobernd, the video watch commander, and I do salute him, downloads all the data on board for further viewing during the off season. Imagine all the viewing that has to be done? For instance fifteen videos were taken in one day of our ten day cruise, and there are four or five missions a year. To avoid reef video insanity, the data is viewed in thirty second intervals which is still a great deal of work.

Fish brought on board are immediately classified to species, and then measured individually. Measurement data are called “length frequency,” and hundreds of fish could be measured from one trap. According to a random tally sheet, certain fish are kept to collect “age and growth” data. Again, this could be hundreds of fish. In the ship’s “wet lab,” fish are then dissected. Most fish have a pair of “otolith” bones (i.e., ear stones) in their head. Otoliths are collected at sea, but sent to a lab where they will be examined under a microscope. When otoliths are cut by a delicate saw, visible rings tell the age of a fish, similar to how the rings visible on a tree stump can tell the age of a tree. Fish are further dissected to check the condition of their reproductive systems.

In the next blog I will I write about the “CTD” device.

July 28, 2011March 12, 2021

Cathrine Fox: Issue Six: Alaska, impossibly big and impossibly green

NOAA TEACHER AT SEA
CATHRINE PRENOT FOX
ONBOARD NOAA SHIP OSCAR DYSON
JULY 24 – AUGUST 14, 2011

Mission: Walleye Pollock Survey

Location: Kodiak, Alaska

Date: July 27, 2011

Weather Data from the Bridge

True Wind Speed: na

Air Temperature: 14° C dry/12° C wet

Air Pressure: na

Overcast

Latitude: 57.44° N, Longitude: 152.31° W

Ship heading: n/a

(Limited data, as ship is in port)

Scientific Log:

I’ve received an in-depth tour of the ship and labs, and I am starting to piece together how the “Acoustic Trawl Survey” works. Basically, NOAA is responsible for monitoring the populations of walleye pollock and accomplishes this task in several ways. The acoustic trawl survey is one part of how this is done.

The science team identifies particular transect areas in the Gulf of Alaska. The ship travels to that area, then transmits acoustic signals about once per second as it travels along each transect. The returning echo gives scientists an initial measurement of the abundance of organisms in the water below the ship. Just “listening,” however, is not enough. We also have to sample populations physically to determine the ages, sizes, and species of the organisms. The ship trawls for these additional data.

A trawl is a large net towed behind the ship to catch fish and other organisms. The individuals (of all species) in the catch are identified and counted. Cameras (three) are mounted inside the back of the trawl (codend) to collect images as they pass through the trawl. From this larger catch, a sample of the walleye pollock (about 300 individuals) are dissected to determine sex, diet, measured (length and weight) for size and aged by looking at (yes) their ear bones or otoliths. I’ll cover all of this in depth once I have been able to do it and see it in action, but that is the gist.

Personal Log:

I think first impressions are important. Alaska? Alaska is impossibly big and impossibly green. Too big, perhaps to describe with common adjectives. It took me about two days of travel from the 4-Corners to make my way up here: a Beechcraft 1900 from Cortez to Denver, then flights from Denver to Seattle and Seattle to Anchorage. I spent the night in Anchorage and wandered the city at midnight… …not that you can tell that it was so late from the pictures.

The next morning I took off from Anchorage and met up with the crew and scientific party onboard the Oscar Dyson in Kodiak, an island the size of Connecticut in the Gulf of Alaska

As for how ‘impossibly green’ Alaska is, I was thinking about the reasons Georgia O’Keeffe gave for moving from New York City to New Mexico in 1949. She said (and I paraphrase) that she wanted to use more vibrant colors in her palette of paints than just green. Ms. O’Keeffe would have it rough here in Alaska: greens, greys and blues abound. Adventures in a Blue World Issue 6 may not convince you of the colors of Alaska, but I hope it gives you a grasp of its size.

I’ve already settled in to the ship and my stateroom. My stateroom is small but comfortable, and I share it with a woman who is part of the scientific NOAA team. Interestingly, she worked for the same professor at the Rocky Mountain Biological Laboratory in Gothic, Colorado as an undergraduate that I did. Very Small World.

We are docked in Kodiak for a few more days than anticipated: we are awaiting the arrival of another deck-hand, and there are a few repairs that need to be made to the ship. Once we get started, I will be working the 4am-4pm shift, and taking part in whatever science is taking place. In the meantime, I get to ‘nose around’ Kodiak, go for hikes and runs, check out museums (see below), and eat as many salmonberries as I can stuff into my mouth.

Until our next adventure,
Cat