Barney Peterson: Rescue at Sea, August 23, 2016

NOAA Teacher at Sea
Barney Peterson

Aboard NOAA Ship OREGON II
August 13 – 28, 2016

 

Mission: Shark/Red Snapper Longline Survey

Geographic Area of Cruise: Gulf of Mexico

Date: Tuesday, August 23, 2016

Weather Data from the Bridge:

Latitude: 28 10.999 N

Longitude:  084 09.706 W

Air temperature: 90.68 F

Pressure: 1020.05 Mb

Sea Surface Temperature: 32.6 C

Wind Speed: 4.74 Kt

Science Log:

Rescue At Sea!

About mid-morning today the ship’s electrician found me to tell me that the night shift crew had just reported seeing a Sea Turtle near the line that they were currently deploying.  The turtle swam over the line and then dove toward the baited hooks some 30 meters down near the bottom.  Nobody is supposed to catch Sea Turtles; the stress of being on the hook can be fatal so immediate recovery and release is required in the case of an accidental catch.  The crew went into immediate pro-active rescue mode!

Loggerhead Turtle

File photo of a Loggerhead Turtle.

The deployment was stopped. The line was cut and a final weight and a second hi-flyer were deployed to mark the end of the set for retrieval.  The Captain altered course to bring the ship back around to a point where we began retrieving the line.  Crew moved to the well deck and prepared the sling used to retrieve large sharks; it would be used to bring a turtle gently to the deck in the event that we had to remove a hook.

As retrieval started and gangions were pulled aboard, it became obvious that this set was in a great location for catching fish.  8 or 9 smallish Red Grouper were pulled in, one after another. Many of the other hooks were minus their bait.  The crew worked the lines with a sense of urgency much more intense than on a normal retrieval!  If a turtle was caught on a hook they wanted it released as quickly as possible to minimize the trauma.

As the final hi-flyer got closer and the last of the gangions was retrieved, a sense of relief was obvious among the crew and observers on the deck.  The turtle they spotted had gone on by without sampling the baited hooks.

On this ship there are routines to follow and plans in place for every emergency.  The rescue of an endangered animal is attended to with the same urgency and purpose as any other rescue.  The science and deck crews know those routines and slip into them seamlessly when necessary to ensure the best possible result.  This is all part of how they carry out NOAA’s mission of stewardship in our oceans.

Personal Log:

Here is Where I Live

I am assigned a bunk in a stateroom shared with another science crew member.  I am assigned to the top bunk and my roomie, Chrissie Stepongzi, is assigned to the bottom.  Climbing the ladder to the top bunk when the ship is rolling back and forth is like training to be an Olympic gymnast!  But, I seem to have mastered it!  Making my bed each morning takes determination and letting go of any desire for perfection: you just can’t get to “no wrinkles!”

stateroom

Find the Monroe Eagle in my nest aboard the OREGON II

Chrissie works the midnight to noon shift and I work noon to midnight so the only time we really see each other is at shift change.  Together, we are responsible for keeping our space neat and clean and respecting each other’s privacy and sleep time.

I eat in the galley, an area open to all crew 24/7. Meals are served at 3 regular times each day.  The food is excellent!  If you are on shift, working and can’t break to eat at meal time, you can request that a plate be saved for you.  The other choice for those off-times is to eat a salad, sandwich, fruit or other snack items whenever you need an energy boost.  We are all responsible for cleaning up after ourselves in the galley.  Our Chief Steward Valerie McCaskill and her assistant, Chuck Godwin, work hard to keep us well-fed and happy.

Galley

Everyone on the ship shares space in the galley where seats are decorated with the symbol of the New Orleans Saints… somebody’s favorite team.

There is a lounge, open to everyone for reading, watching movies, or hanging out during down time.  There is a huge selection of up-to-date videos available to watch on a large screen and a computer for crew use.  Another place to hang out and talk or just chill, is the flying deck.  Up there you can see for miles across the water while you sit on the deck or in one of two Adirondack chairs.  Since the only shade available for relaxing is on this deck it can be pretty popular if there is a breeze blowing.

Lounge

During off-duty times we can read, play cards or watch movies in the lounge.

Flying Bridge

The flying bridge is a place to relax and catch a cool breeze when there is a break in the work.

My work area consists of 4 stations: the dry lab which has computers for working with data, tracking ship movements between sample sites, and storing samples in a freezer for later study;

Dry Lab

The dry lab where data management and research are done between deployments

the wet lab which so far on this cruise, has been used mainly for getting ready to work on deck, but has equipment and storage space for processing and sampling our catch; the stern deck where we bait hooks and deploy the lines and buoys; the well deck at the front of the ship where lines and buoys are retrieved, catch is measured and released or set aside for processing, and the CTD is deployed/stored for water sampling.

We move between these areas in a rhythm dictated by the pace of our work.  In between deployments we catch up on research, discuss procedures, and I work on interviews and journal entries.  I am enjoying shipboard life.  We usually go to bed pretty tired, that just helps us to sleep well.  The amazing vistas of this ocean setting always help to restore my energy and recharge my enthusiasm for each new day.

sunset

Beautiful sunsets are the payoff for hot days on the deck.

 

Barney Peterson: Cut Bait and Fish! August 17, 2016

NOAA Teacher at Sea
Barney Peterson

Aboard NOAA Ship OREGON II
August 13 – 28, 2016

 

Mission: Shark/Red Snapper Longline Survey

Geographic Area of Cruise: Gulf of Mexico

Date: Wednesday, August 17, 2016

Weather Data from the Bridge:

Latitude: 25 29.664 N

Longitude: 082 02.181 W

Air temperature: 84.56 F

Pressure: 1018.13 Mb

Sea Surface Temperature: 30.5 C

Wind Speed: 13.54 Kt    East 12.72 degrees

Science Log:

The fishing process on the ship repeats itself in a well-defined cycle: cut bait, bait 100 hooks, drop hi-flyer, drop weight,  attach 50 tags and baited hooks, drop weight, attach 50 more tags and hooks, drop weight, deploy hi-flyer.  Put the CTD over the side and retrieve for water quality data.  Wait an hour.  Retrieve hi-flyer, retrieve weight, pull in first 50 hooks and detach tags logging any catch as they come in, retrieve weight, pull in next 50 hooks and detach tags logging any catch as they come in, retrieve last weight, retrieve last hi-flyer.  Process the catch as it comes in, logging tag number, gender, species, lengths at 3 points, life stage, and tag number if the catch is a shark that gets tagged, return catch to water alive as quickly as possible. Transit to the next sample site.  Wash, rinse and repeat.

That boils it down to the routine, but long line fishing is much more interesting and exciting than that!  Bait we use is Atlantic Mackerel, caught farther north and frozen, thawed just before use and cut into 3 pieces per fish.  A circle hook is inserted through each piece twice to ensure it will not fall off the hook…this is a skill that takes a bit of practice.  Sometimes hooks are pulled in with bait still intact. Other times the bait is gone and we don’t know if it was eaten without the hook catching, a poor baiting job, or more likely eaten by smaller fish, too little to be hooked.  When we are successful we hear the call “FISH ON!” and the deck comes alive.

The line with a catch is pulled up as quickly and carefully as possible.  Some fish are not securely hooked and are lost between the water and the deck…not what we want to happen.  If the catch is a large shark (generally 4 feet or longer) it is raised to the deck in a sling attached to the forward crane to minimize the chance of physical injury.  For large sharks a camera with twin lasers is used to get a scaled picture for estimating length.  There is a dynamometer on the line between the sling and the crane which measures pressure and converts it to weight.  Both of these processes help minimize the time the shark needs to be out of water with the goal of keeping them alive to swim away after release.  A tag is quickly attached to the shark, inserted under the skin at the base of the second dorsal fin.  A small clip is taken from a fin, preferably from the pelvic fin, for DNA studies. The sling is lowered back to the water and the shark is free to swim away.  All data collected is recorded to the hook-tag number which will identify the shark as to geographic location of the catch.

Shark in sling

A sandbar shark being held in the sling for measurements.

Sometimes the catch is a smaller shark or a bony fish:  a Grouper, a Red Snapper, or any one of many different types of fish that live in this area.  Each of these is brought onto the deck and laid on a measuring board. Species, length, and weight are recorded. Fin clips are taken.  Many of them are on the list of species of recreational and commercial importance.  These fish are retained for life history studies which will inform future management decisions.  In the lab they are dissected to retrieve otoliths (ear stones) by which their age is determined.  Depending upon the species, gonads (the reproductive organs) may be saved for study to determine the possibilities of future reproductive success.  For certain species a good-sized piece of flesh is cut from the side for fraudulent species voucher library use.

After the smaller sharks are measured, fin clipped, gender identified, life stage is determined and weight is taken, they are tagged and returned to the water as quickly as possible.  Tags on these sharks are a small, numbered plastic tag attached by a hole through the first dorsal fin.

This is a lot to get done and recorded and it all happens several times each shift.  The routine never varies.  The amount of action depends upon the success of the catch from any particular set.  This goes on 24 hours per day.  The only breaks come as we travel between the sites randomly selected for our sets and that time is generally spent in the lab.

(Thanks go to Kevin Rademacher, Trey Driggers and Lisa Jones, Research Fisheries Biologists, for contributing to this entry.  File photo NOAA/NMFS)

Personal Log:

I do not need 12 hours of sleep.  That means I have several hours at the start or end of each shift to write in my journal, talk to the other members of the crew, take care of personal business such as laundry and communicate with home via email.  Even so, every day seems to go by very quickly and I go to bed thinking of all the things I have yet to learn.  In my next posts I will tell more about the different kinds of sharks and introduce you to some of the other people on the ship.  Stay tuned.

Denise Harrington, Getting Ready for an Adventure, April 23, 2016

NOAA Teacher at Sea
Denise Harrington
(Almost) aboard NOAA Ship Pisces
May 04, 2016 – May 17, 2016

Greetings from Garibaldi, Oregon. My name is Denise Harrington and I teach Second Grade at South Prairie Elementary School in Tillamook, Oregon, along the north Oregon coast. There are 300 amazing second and third graders at our school who can prove to you that no matter how young you are, you can be a great scientist.  Last year they were caught on camera by Oregon Field Guide studying the diversity of life present in our ocean.

 

I applied to become a NOAA Teacher at Sea because I wanted to work with scientists in the field. I seem to learn best by doing.  In 2014, I joined the crew of NOAA ship Rainier, mapping the ocean floor near Kodiak Island, Alaska.  I learned how vast, connected, and undiscovered our oceans are. Students watched in disbelief after we discovered a sea floor canyon.  I learned about the technology and skills used to map the ocean floor. I learned how NOAA helps us stay safe by making accurate nautical charts.  It was, for our students and myself, a life changing experience.

As an avid sea kayaker, I was able to share my deeper understanding of the ocean with fellow paddlers. Photo courtesy of Bill Vonnegut

Now, I am fortunate enough to participate in another NOAA survey. On this survey aboard NOAA ship Pisces, scientists will be collecting data about how many fish inhabit the area along banks and ledges of the Continental Shelf of the Gulf of Mexico.
NOAA believes in the value of sharing what they do with the public, and students in particular. The crew of Pisces even let fifth grader students from Southaven, Mississippi name the ship after they won a writing contest. Maybe you can name the next NOAA ship!

On May 3, 2016, Ship Pisces will begin Leg 3 of their survey of reef fish. I have so many questions.  I asked Chief Scientist Kevin Rademacher why the many survey partners chose snapper and grouper to survey. He replied “Snapper and grouper are some of the most important commercial fisheries here in the Gulf of Mexico. There are 14 species of snapper in the Gulf of Mexico that are good to eat. Of those the most commercially important is the red snapper. It is also currently over-fished.”   When I hear “over-fished” I wonder if our second graders will have many or any red snapper to eat when they they grow up. Yikes!

Another important commercial catch is grouper.  My brother, Greg, who fishes along the Kenai River in Alaska understands why grouper is a focus of the survey. “It’s tasty,” he says. I can’t believe he finds grouper tastier than salmon.  NOAA is making sure that we know what fish we have and make sure we save some for later, so that everyone can decide which fish is the tastiest when they grow up.

I have so many questions keeping me up at night as I prepare for my adventure. What do I need to know about fish to do my job on the ship?  Will I see evidence of the largest oil spill in U.S. history, the Deepwater Horizon spill? How crowded will we all be aboard Ship Pisces? If I dissect fish, will it be gross? Will it stink?  Will I get sea sick? With my head spinning with questions, I know I am learning. Yet there is nothing more I can do now to prepare myself for all that I will learn, except to be early to the airport in Portland, Oregon, and to the ship in Pascagoula, Mississippi, on May 3rd.

I will get home in time to watch my daughter, Elizabeth, graduate from high school.  Ever since I returned from the NOAA cruise in Alaska, she has been studying marine biology and even competed in the National Ocean Sciences Bowl.

liz with a crab

 

During research in the Gulf of Mexico with the crew of Ship Pisces, I will learn about the many living things in the Gulf of Mexico and about the technology they use to protect and manage commercial fisheries.  Soon, you will be able to watch me collect data about our ocean critters. Hope for fair winds and following seas as I join the crew on Ship Pisces, “working to protect, restore, and manage the use of our living ocean resources.”

Jeff Miller: Sharks and Dead Zones, September 12, 2015

NOAA Teacher at Sea
Jeff Miller
Aboard NOAA Ship Oregon II
August 31 – September 14, 2015

Mission: Shark Longline Survey
Geographical Area: Gulf of Mexico
Date: September 12, 2015

Data from the Bridge
Ship Speed:  9.2 knots
Wind Speed:  8.8 knots
Air Temp: 27,7°C
Sea Temp: 30.2°C
Seas: 1-2 meters
Sea Depth:  457 meters

GPS Coordinates
Lat:  27 47.142 N
Long:  094 04.264 W

Science and Technology Log
On September 8 – 9, we surveyed a number of stations along the Texas and Louisiana coasts that were in shallow water between 10-30 meters (approximately 30-100 feet).  Interestingly, the number of sharks we caught at each station varied dramatically.  For example, we pulled up 65 sharks at station 136 and 53 sharks at station 137, whereas we caught only 5 sharks at station 138 and 2 sharks at station 139.  What could account for this large variance in the number of sharks caught at these locations?

Weighing a bonnethead shark

Weighing a bonnethead shark caught off the coast of Texas.

One key factor that is likely influencing shark distribution is the amount of dissolved oxygen in the water.  Oxygen is required by living organisms to produce the energy needed to fuel all their activities.  In water, dissolved oxygen levels above 5 mg/liter are needed for most marine organisms to thrive. Water with less than 2 mg/liter of dissolved oxygen is termed hypoxic, meaning dissolved oxygen is below levels needed by most organisms to thrive and survive.  Water with less than 0.2 mg/liter of dissolved oxygen is termed anoxic (no oxygen) and results in  “dead zones” where little, if any, marine life can survive.

As part of several missions, including the ground fish and longline shark surveys, NOAA ships sample the levels of dissolved oxygen at survey stations in coastal waters of the Gulf of Mexico.  Measurements of dissolved oxygen, salinity, and temperature are collected by a device called the CTD.   At each survey station, the CTD is deployed and it collects real-time measurements as it descends to the bottom and returns to the surface.

CTD

Standing with the CTD, which is used to measure dissolved oxygen, salinity, and temperature.

Data collected by the CTD is used to produce maps showing the relative levels of dissolved oxygen in coastal regions of the Gulf of Mexico.    For more environmental data go to the NOAA National Centers for Environmental Information.

2015 Gulf Hypoxia Map

Map showing dissolved oxygen levels in the coastal areas of the Gulf of Mexico. Red marks anoxic/hypoxic areas with low dissolved oxygen levels.  Source: NOAA National Centers for Environmental Information.

Environmental surveys demonstrate that large anoxic/hypoxic zones often exist along the Louisiana/Texas continental shelf.  Because low dissolved oxygen levels are harmful to marine organisms, the anoxic/hypoxic zones in the northern Gulf of Mexico could greatly impact commercially and ecologically important marine species.  Overwhelming scientific evidence indicates that excess organic matter, especially nitrogen, from the Mississippi River drainage basin drives the development of anoxic/hypoxic waters.  Although natural sources contribute to the runoff, inputs from agricultural runoff, the burning of fossil fuels, and waste water treatment discharges have increased inputs to many times natural levels.

Runoff in the Mississippi basin

Map showing sources of nitrogen runoff in the Mississippi River drainage basin. Source NOAA National Centers for Coastal Ocean Science.

Nitrogen runoff from the Mississippi River feeds large phytoplankton algae blooms at the surface.  Over time, excess algae and other organic materials sink to the bottom.  On the bottom, decomposition of this organic material by bacteria and other organisms consumes oxygen and leads to formation of anoxic/hypoxic zones.  These anoxic/hypoxic zones persist because waters of the northern Gulf of Mexico become stratified, which means the water is separated into horizontal layers with cold and/or saltier water at the bottom and warmer and/or fresher water at the surface. This layering separates bottom waters from the atmosphere and prevents re-supply of oxygen from the surface.

Since levels of dissolved oxygen can  greatly influence the distribution of marine life, we reasoned that the high variation in the number of sharks caught along the Louisiana/Texas coast could be the result of differences in dissolved oxygen.  To test this idea, we analyzed environmental data and shark numbers at survey stations along the Louisiana/Texas coast.  The graphs below show raw data collected by the CTD at stations 137 and 138.

CTD 137

Dissolved oxygen levels at station 137 (green line; raw data). At the surface: dissolved oxygen = 5.0 mg/liter. At the bottom: dissolved oxygen = 1.5 mg/liter.  Notice the stratification of the water at a depth of 7-8 meters.

 

CTD 138

Dissolved oxygen levels at station 138 (green line; raw data).  At the surface: dissolved oxygen = 5.5 mg/liter. At the bottom: dissolved oxygen = 0 mg/liter.  Notice the stratification of the water at a depth of 7-8 meters.

Putting together shark survey numbers with environmental data from the CTD we found that we caught very high numbers of sharks in hypoxic water and we caught very few sharks in anoxic water.  Similar results were observed at station 136 (hypoxic waters; 65 sharks caught) and station 139 (anoxic waters; 2 sharks caught).

Data table

Relationship between dissolved oxygen levels and numbers of sharks caught at stations 137 and 138.

What can explain this data?  One possible answer is that sharks will be found where there is food for them to eat.  Thus, many sharks may be moving in and out of hypoxic waters to catch prey that may be stressed or less active due to low oxygen levels.  In other words, sharks may be taking advantage of low oxygen conditions that make fish easier to catch.  In contrast, anoxic waters cannot support marine life so there will be very little food for sharks to eat and, therefore, few sharks will be present.  While this idea provides an explanation for our observations, more research, like the work being done aboard the NOAA Ship Oregon II, is needed to understand the distribution and movement of sharks in the Gulf of Mexico.

Personal Log
My time aboard the Oregon II is drawing to a close as we move into the last weekend of the cruise.  We have now turned away from the Louisiana coast into deeper waters as we travel west to Galveston, Texas.  The weather has changed as well.  It has been sunny and hot for much of our trip, but clouds, rain, and wind have moved in.  Despite this change in weather, we continue to set longlines at survey stations along our route to Galveston.  The rain makes our job more challenging but our catch has been relatively light since we moved away from the coast into deeper waters.  Hopefully our fishing luck will change as we move closer to Galveston.  I would like to wrestle a few more sharks before my time on the Oregon II comes to an end.

Jeff Miller: Wrestling Sharks for Science, September 9, 2015

NOAA Teacher at Sea
Jeff Miller
Aboard NOAA Ship Oregon II
August 31 – September 14, 2015

Mission: Shark Longline Survey
Geographical Area: Gulf of Mexico
Date: September 9, 2015

Data from the Bridge
Ship Speed: 9.4 knots
Wind Speed: 6.75 knots
Air Temp: 29.4°C
Sea Temp: 30.4°C
Seas: <1 meter
Sea Depth: 13 meters

GPS Coordinates
Lat:  N 29 25.103
Long:  W 092.36.483

Science and Technology Log
The major goal of our mission is to survey shark populations in the western Gulf of Mexico and collect measurements and biological samples.  The sharks are also tagged so if they are re-caught scientists can learn about their growth and movements.

Sharks are members of the class of fishes called Chondrichthyes,which are cartilaginous fishes meaning they have an internal skeleton made of cartilage.  Within the class Chondricthyes, sharks belong to the subclass Elasmobranchii together with their closest relatives the skates and rays.  There are about 450 species of living sharks that inhabit oceans around the world.

Sharks, or better put their ancient relatives, have inhabited the oceans for approximately 450 million years and have evolved a number of unique characteristics that help them survive and thrive in virtually all parts of the world.  The most recognizable feature of sharks is their shape.  A shark’s body shape and fin placement allow water to flow over the shark reducing drag and making swimming easier.  In addition, the shark’s cartilaginous skeleton reduces weight while providing strength and flexibility, which also increases energy efficiency.

Blacktip shark

Measuring a blacktip shark on deck. The blacktip shark shows the typical body shape and fin placement of sharks. These physical characteristics decrease drag and help sharks move more efficiently through water.

When I held a shark for the first time, the feature I noticed most is the incredible muscle mass and strength of the shark.  The body of a typical shark is composed of over 60% muscle (the average human has about 35-40% muscle mass).  Most sharks need to keep swimming to breathe and, therefore, typically move steadily and slowly through the water.  This slow, steady movement is powered by red muscle, which makes up about 10% of a sharks muscle and requires high amounts of oxygen to produce fuel for muscle contraction.  The other 90% of a sharks muscle is called white muscle and is used for powerful bursts of speed when eluding predators (other sharks) or capturing prey.

Since sharks are so strong and potentially dangerous, one lesson that I learned quickly was how to properly handle a shark on deck.  Smaller sharks can typically be handled by one person.  To hold a small shark, you grab the shark just behind the chondrocranium (the stiff cartilage that makes up the “skull” of the shark) and above the gill slits.  This is a relatively soft area that can be squeezed firmly with your hand to hold the shark.  If the shark is a bit feisty, a second hand can be used to hold the tail.

Holding a sharpnose shark

Smaller sharks, like this sharpnose shark, can be held by firmly grabbing the shark just behind the head.

Larger and/or more aggressive sharks typically require two sets of hands to hold safely.  When two people are needed to hold a shark, it is very important that both people grab the shark at the same time.  One person holds the head while the other holds the tail.  When trying to hold a larger, more powerful shark, you do not want to grab the tail first.  Sharks are very flexible and can bend their heads back towards their tail, which can pose a safety risk for the handler.  While holding a shark sounds simple, subduing a large shark and getting it to cooperate while taking measurements takes a lot of focus, strength, and teamwork.

Holding a blacktip shark

Teamwork is required to handle larger sharks like this blacktip shark, which was caught because it preyed on a small sharpnose shark that was already on the hook.

 

Measuring a blacktip shark

Collecting measurements from a large blacktip shark.

 

Holding a blacktip shark

Holding a blacktip shark before determining its weight.

When a shark is too big to bring on deck safely, the shark is placed into a cradle and hoisted from the water so it can be measured and tagged.  We have used the cradle on a number of sharks including a 7.5 foot tiger shark and a 6 foot scalloped hammerhead shark.  When processing sharks, we try to work quickly and efficiently to measure and tag the sharks to minimize stress on the animals and time out of the water.  Once our data collection is complete, the sharks are returned to the water.

Tiger shark in the cradle

Large sharks, like this tiger shark, are hoisted up on a cradle in order to be measured and tagged.

Personal Log
We are now in full work mode on the ship.  My daily routine consists of waking up around 7:30 and grabbing breakfast.  After breakfast I like to go check in on the night team to see what they caught and determine when they will do their next haul (i.e. pull in their catch).  This usually gives me a couple hours of free time before my shift begins at noon.  I like to use my time in the morning to work on my log and go through pictures from the previous day.  I eat lunch around 11:30 so I am ready to start work at noon.  My shift, which runs from noon to midnight, typically includes surveying three or four different stations.  At each station, we set our baited hooks for one hour, haul the catch, and process the sharks and fishes.  We process the sharks immediately and then release them, whereas we keep the fish to collect biological samples (otoliths and gonads).  Once we finish processing the catch, we have free time until the ship reaches the next survey station.  The stations can be anywhere from 6 or 7 miles apart to over 40 miles apart.  Therefore, our downtime throughout the day can vary widely from 30 minutes to several hours (the ship usually travels at about 10 knots; 1 knot = 1.15 mph).  At midnight, we switch roles with the night team.  Working with fish in temperatures reaching  the low 90°s will make you dirty.  Therefore, I typically head to the shower to clean up before going to bed.  I am usually in bed by 12:30 and will be back up early in the morning to do it all over again.  It is a busy schedule, but the work is interesting, exciting, and fun.  I feel very lucky to be out here because not many people get the opportunity to wrestle sharks.  This is one experience I will always remember.

Jeff Miller: Fishing for Sharks and Fishes, September 6, 2015

NOAA Teacher at Sea
Jeff Miller
Aboard NOAA Ship Oregon II
August 31 – September 14, 2015

Mission: Shark Longline Survey
Geographical Area: Gulf of Mexico
Date: September 6, 2015

Data from the Bridge
Ship Speed: 9.7 knots
Wind Speed: 5.6 knots
Air Temp: 30.9°C
Sea Temp: 31.1°C
Seas: <1 meter
Sea Depth: 52 meters

GPS Coordinates
Lat:  N 28 06.236
Long:  W 095 15.023

Science and Technology Log
Our first couple days of fishing have been a great learning experience for me despite the fact that the fish count has been relatively low (the last three sets we averaged less than 5 fish per 100 hooks).  There are a number of jobs to do at each survey station and I will rotate through each of them during my cruise. These jobs include baiting the hooks, numbering and setting the hooks on the main line, hauling in the hooks, measuring and weighing the sharks/fish, and processing the shark/fish for biological samples.

Numbering the baited hooks

Each gangion (the baited hook and its associate line) is tagged with a number before being attached to the main line.

 

Number clips

A number clip is attached to each gangion (baited hook and its associated line) to catalog each fish that is caught.

After the line is deployed for one hour, we haul in the catch.  As the gangions come in, one of us will collect empty hooks and place them back in the barrel to be ready for the next station.  Other members of the team will process the fish we catch.  The number of fish caught at each station can vary widely.  Our team (the daytime team) had two stations in a row where we caught fewer than five fish while the night team caught 57 fish at a single station.

Collecting empty hooks

Empty hooks are collected, left over bait is removed, and the gangion is placed back in the bucket to be ready for the next station.

So far we have caught a variety of fishes including golden tilefish, red snapper, sharpnose sharks, blacknose sharks, a scalloped hammerhead, black tip sharks, a spinner shark, and smooth dogfish.  The first set of hooks we deployed was at a deep water station (sea depth was approx. 300 meters or 985 feet) and we hooked 11 golden tilefish, including one that weighed 13 kg (28.6 pounds).

Golden tilefish

On our first set of hooks in deep water, we caught a number of golden tilefish including this fish that weighed nearly 30 pounds.

We collect a number of samples from fishes such as red snapper and golden tilefish.  First we collect otoliths, which are hard calcified structures of the inner ear that are located just behind the brain.  Scientists can read the rings of the otolith to determine the approximate age and growth rate of the fish.

Otolith

Otoliths can be read like tree rings to approximate the age and growth rate of bony fishes.  Photo credit: NOAA Marine Fisheries.

The answer to the poll is at the end of this post.

You can try to age fish like NOAA scientists do by using the Age Reading Demonstration created by the NOAA Alaska Fisheries Science Center.  Click here to visit the site.

When sharks are caught, we collect information about their size, gender, and sexual maturity.  You may be wondering, “how can you determine the sex of a shark?”  It ends up that the answer is actually quite simple.  Male sharks have two claspers along the inner margin of the pelvic fins that are used to insert sperm into the cloaca of a female.  Female sharks lack claspers.

Male female shark

Male and female sharks can be distinguished by the presence of claspers on male sharks.

Personal Log
After arriving at our first survey station on Thursday afternoon (Sep. 3), everyone on the ship is in full work mode.  We work around the clock in two groups: one team, which I belong to, works from noon to midnight, and the other team works from midnight to noon.  The crew and science teams work very well together – everyone has a specific job as we set out hooks, haul the catch, and process the fishes.  It’s a well oiled machine and I am grateful to the crew and my fellow science team members for helping me learn and take an active role the process.  I am not here as a passive observer.  I am truly part of the scientific team.

I have also learned a lot about the fishes we are catching.  For example, I have learned how to handle them on deck, how to process them for samples, and how to filet them for dinner.  I never fished much my life, so pretty much everything I am doing is new to me.

I have also adjusted well to life on the ship.  Before the cruise, I was concerned that I may get seasick since I am prone to motion sickness.  However, so far I have felt great even though we have been in relatively choppy seas (averaging about 1-2 meters or 3 to 6 feet) and the ship rocks constantly.  I have been using a scopolamine patch, an anticholinergic drug that decreases nausea and dizziness, and this likely is playing a role. Whether it’s just me or the medicine, I feel good, I’m sleeping well, and I am eating well.  The cooks are great and the food has been outstanding.  All in all, I am having an amazing experience.

Poll answer:  This fish is approximately nine years old (as determined by members of my science team aboard the Oregon II).

Jeff Miller: Cruising to the Survey Stations, September 2, 2015

NOAA Teacher at Sea
Jeff Miller
Aboard NOAA Ship Oregon II
August 31 – September 14, 2015

Mission: Shark Longline Survey
Geographical Area: Gulf of Mexico
Date: September 2, 2015

Data from the Bridge
Ship Speed: 11.6 knots
Wind Speed: 7 knots
Air Temp:  24.7°C
Sea Temp:  29.6°C
Seas:  3-4 ft.
Sea Depth: 589 meters

GPS Coordinates
Lat: 28 01.364 N
Long: 091 29.104 W

Cruising Map

Map showing our current location and the site of our first survey station

Science and Technology Log
After a one day delay in port at Pascagoula, MS we are currently motoring southwest towards our first survey station in the Gulf of Mexico near Brownsville, TX. Our survey area will include random stations roughly between Brownsville and Galveston, TX.

Survey stations are randomly selected from a predetermined grid of sites.  Possible stations fall into three categories: (A) stations in depths 9-55 meters (5-30 fathoms), (B) stations in depths between 55-183 meters (30-100 fathoms), and (C) stations in depths between 183-366 meters (100-200 fathoms).  On the current shark longline surveys, 50% of the sites we survey will be category A sites, 40% will be category B sites, and 10% will be category C sites.  Environmental data is also collected at each station including water temperature, salinity, and dissolved oxygen.

Several questions you may have are why do a shark survey, how do you catch the sharks, and what do you do with the sharks once they are caught?  These are great questions and below I will describe the materials and methods we will use to catch and analyze sharks aboard the Oregon II. 

Why does NOAA perform shark surveys?
Shark surveys are done to gather information about shark populations in the Gulf of Mexico and to collect morphological measurements (length, weight) and biological samples for research.

How are shark surveys performed?
At each collection station, a one mile line of 100 hooks baited with Atlantic Mackerel is used to catch sharks. The line is first attached to a radar reflective highflyer (a type of buoy that can be detected by the ship’s radar).  A weight is then attached to the line to make it sink to the bottom.  After the weight is added, about 50 gangions with baited hooks are attached to the line.  At the half mile point of the line, another weight is attached then the second 50 hooks.  After the last hook, a third weight is added then the second highflyer.  The line is left in the water for one hour (time between last highflyer deployed and first highflyer retrieved) and then is pulled back on to the boat to assess what has been caught.  Small sharks and fishes are brought on deck while larger sharks are lifted into a cradle for processing.

Longline equipment

Sampling gear used includes two highflyers, weights, and 100 hooks

 

Longline hooks

Longline hooks used for the shark survey

 

Longline hooks

Longline hooks used in the shark survey

 

Shark cradle

Shark cradle used to collect information about large sharks

 

What data is collected from the sharks?
Researchers collect a variety of samples and information from the caught sharks.  First, the survey provides a snapshot of the different shark species and their relative abundance in the Gulf of Mexico.  Second, researchers collect data from individual sharks including length, weight and whether the shark is reproductively mature.  Some sharks are tagged to gather data about their migration patterns.  Each tag has an identification number for the shark and contact information to report information about where the same shark was re-caught.  Third, biological samples are collected from sharks for more detailed analyses.  Tissues collected include fin clips (for DNA and molecular studies), muscle tissue (for toxicology studies), blood (for hormonal studies), reproductive organs (including embryos if present), and vertebrae (for age and growth studies).

Personal Log
One of the desired traits for participants in the Teacher at Sea program is flexibility – cruising schedules and even ports can change.  I have now experienced this first-hand as we were delayed in port in Pascagoula, MS for an extra day.  Though waiting an extra day really isn’t a big deal, it is hard to wait since myself and the rest of the scientific crew are all anxious to begin the shark survey.  Since we also have two days of cruising to reach our first survey site, this means we all have to find ways to pass the time.  I have used some of my time trying to learn about the operation of the ship as well as the methods we will be using to perform the longline survey.  I also watched a couple movies with other members of the science team.  The ship has an amazing library of DVDs.

The Oregon II

Getting ready to leave Pascagoula aboard the NOAA Ship Oregon II

Safety is very important aboard the Oregon II so today we performed several drills including an abandon ship drill.  This drill requires you to wear a survival suit.  Getting mine on was a tight squeeze but I got the suit on in the required time.

Safety suit

In my safety suit during an abandon ship drill

Did You Know?
The NOAA Commissioned Officer Corps is one of the seven uniformed services of the United States.  Can you name the other six uniformed services?  Think about this and check the answer at the bottom of this post.

NOAA Corps Officers perform many duties that include commanding NOAA’s research and survey vessels, flying NOAA’s hurricane and environmental monitoring planes, and managing scientific and engineering work needed to make wise decisions about our natural resources and environment.

Answer: The seven uniformed services of the United States are: (1) Army, (2) Navy, (3) Air Force, (4) Marine Corps, (5) Coast Guard, (6) NOAA Commissioned Officer Corps, and (7) Public Health Service Commissioned Corps.