Tag: bottom trawl

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Sue Zupko, Getting Ready: Is it a Go? September 4, 2014

NOAA Teacher at Sea
Sue Zupko
(soon to be) Aboard NOAA Ship Henry Bigelow
September 7-19, 2014

Mission: Autumn Bottom Trawl Survey Leg I
Geographical area of cruise:  Cape May, NJ to Cape Hatteras, NC
Date: September 4, 2014

Personal Log

I am a teacher of the Gifted and Talented at Weatherly Heights Elementary School in Huntsville, AL.  I am so very humbled by the opportunity I have been given to conduct research aboard the Henry B. Bigelow with NOAA scientists.  This is my second NOAA cruise.  I studied deep-water corals aboard the Pisces in 2011 and thought it was my only chance to do something like that.  They told me if I did all my homework, and did all my projects well, that good things would come my way.  I say that to my students and this is an example of why one should do one’s homework and try hard.   You’d better believe that I did my best.  I love to learn so a NOAA research cruise and projects with my students are a perfect fit.

Sue in sweatshirt looking up from microscope. Diego in the background.
Me on the Pisces, It was cold in this lab.

In preparing for my first entry I asked my students for advice on what to include.  They insisted that I include a “shout out” to them and tell how fabulous our school is.

Here are a few highlights.  Weatherly has been recycling aluminum cans to help pay for our outdoor classroom since 1998 when I helped write a grant to get a trailer to collect cans and take them to the recycling center.  We have made thousands of dollars through the years and have an Alabama Certified Outdoor Classroom now.  Students, parents, faculty, and community volunteers help with it and enjoy learning there.  We have raised Monarch butterfly larvae, viewed Ladybug larvae under a microscope from the Tulip Poplar tree, grown melons, touched plants in the sensory garden, and myriad other activities.

We piloted a recycling program for our district.  Every classroom has a bin to collect clean paper and plastic.  It is collected weekly and tons of items have been recycled as a result.

We participate in a plastic bottle cap recycling program.  This is an annual contest city-wide and Weatherly counts and recycles thousands of caps to be made into paint buckets rather than taking up room in the landfill.  For many years we recycled phone books and were one of the top three recyclers.

In addition to helping the environment, we are a No Place for Hate school.  We also study about the ocean.  A lot.  I am the faculty advisor for our morning announcements.  Our quotes of the week this year are about the ocean and we highlight an ocean literacy principle  every day.  We now know that marine biologist Sylvia Earle pointed out that “With every drop of water you drink, every breath you take, you’re connected to the sea. No matter where on Earth you live. Most of the oxygen in the atmosphere is generated by the sea.”

On my upcoming voyage with NOAA, I will launch two drifters.  In order to be selected for this drifter project, a teacher must have an international partner to share lessons with to learn about the ocean.  After an extensive search I found the perfect match.  Sarah Hills at the TED Istanbul College teaches English.  Her students will be studying map reading starting in September when they return to school.  We have already decided that our students will plot the course of the drifters and hypothesize where they will be at specific times based on the ocean currents and winds which will carry them.

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These drifters measure ocean salinity, surface water temperature, velocities (speeds) of the current, and air pressure and are important for understanding more about our weather and the ocean.  I can’t wait to get our students communicating.  Weatherly’s school theme is “A Village of Learners and Leaders.”  Outside my classroom on the bulletin board are some wonderful items from Turkey provided by Mrs. Hills and it says, “A Global Village of Learners and Leaders.”  In preparation for tracking our drifters, we are currently tracking former hurricanes and researching how the ocean changes our planet.  On their exit ticket today, my 5th graders commented that they liked tracking the hurricanes since they will use the same technique to track my journey and the drifters.

I am so excited.  I have spoken with the Chief Scientist, John Galbraith, and understand that I will be working side-by-side with scientists on this fisheries cruise.  We will drop a trawl net behind our 209 foot long ship and catch marine creatures.  Our job will be to sort the fish (and other marine animals) and learn more about them using measurements and other means such as dissection.  Computers play a role in our study and my first assignment will be to collect data in the computer.  Wonder what program I will use, and is it similar to Excel which we use a lot?

I asked my fourth graders if they thought I might see a whale.  They all responded yes in that group.  What do you think?

Teachers at Sea need to be flexible, have fortitude, and follow orders.  Let me explain.  Right now I am waiting to see if my ship will even sail.  The engineers have found a problem and are working to make the ship seaworthy for our voyage.  Already our cruise date has changed twice.  I must be flexible and be ready to leave on a moment’s notice.  There are always some changes, it seems, when dealing with the ocean.  On my last cruise a tropical depression (storm) formed over us and we couldn’t begin our research for an extra day.

Sailing is not for the faint of heart.  I must be able to work long hours in uncomfortable conditions (they say this is having fortitude).  They do supply my “foul weather” gear.  Wonder if I will smell like fish at the end of my shift.

One handy piece of equipment I will take is ear plugs.  The engines are loud and that helps when it is time to sleep.  My shift will be either from midnight to noon or noon to midnight.  That’s a long time to work.  If we have a good catch, we will be working a lot.  That is good for weight loss, as long as I don’t overdo with the fabulous food prepared by the stewards (cooks) in the galley (kitchen).

I was in the U.S. Army years ago and learned to follow orders, the third of the 3Fs.  There are NOAA officers whose orders I must follow for my safety and the safety of the other scientists.  I also must follow the orders of the NOAA Teacher at Sea directors and my chief scientist.  Add to that my principal and superintendent in my district.  That’s a lot of bosses giving orders.

Lastly, my students requested that I tell everyone our school motto.  “We are Weatherly Heights and we…GO THE EXTRA MILE.”  Well, pretty soon I can say, “We are the crew and scientists aboard the NOAA Ship Henry B. Bigelow and we…GO THE EXTRA NAUTICAL MILE.”  Can’t wait to see what treasures we will uncover in the ocean.

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Melissa George: Scraping the Bottom-Dwellers, August 6, 2013

NOAA Teacher at Sea
Melissa George
Aboard NOAA Ship Oscar Dyson
July 22 – August 9, 2013

Mission:  Pollock Survey
Geographical Area of Cruise:  Gulf of Alaska
Date:  Tuesday, August 6, 2013

Current Data From Today’s Cruise  (9 am Alaska Daylight Time)

Weather Data from the Bridge 
Sky Condition:  Partly Cloudy
Temperature:  15° C
Wind Speed: 7 knots
Barometric Pressure:  1019.6 mb
Humidity:  90%

August 6, 2013: Partly Cloudy or Partly Mountainy?
August 6, 2013: Partly Cloudy or Partly Mountainy?

Sun and Moon Data
Sunrise:  5:15 am
Sunset:  9:33 pm
Moonrise:  5:33 am
Moonset:  8:45 pm

Geographic Coordinates   ( 9 am Alaska Daylight Time)

Latitude:  59 ° 20.4 N Longitude:  141° 16.6 W
The ship’s position now can be found by clicking:  Oscar Dyson’s Geographical Position

Science and Technology Log

Besides the mid-water trawling, information about the pollock population is gathered in other ways on the Oscar Dyson research vessel.  One of these ways is direct, monitoring the pollock by trawling in other parts of the water column; the other way is indirect, evaluating the prey that the pollock feeds on.

Bottom Trawling

Scientists use acoustics to locate the signal for the fish.  Sometimes this signal is noticed near the ocean floor.  In this case, the PolyNor’eastern (PNE) Bottom Trawl Net is used to trawl for fish.  This net is a large net equipped with rubber bobbins that allow it to get close to the benthic region of the ocean without dragging.

Poly Nor'Eastern Bottom Trawling Net
Poly Nor’Eastern Bottom Trawling Net

During this research expedition, we used the PNE net six times to survey pollock.  Often times these trawls brought up other interesting sea life, that were quickly assessed (identified, measured, and recorded) and returned to the ocean.  The majority of invertebrate sea animals such as poriferans (sponges), cnidarians (sea anemones), annelids (segmented worms), mollusks (barnacles), arthropods (hermit crabs hiding in mollusk shells), and echinoderms (sea urchins and starfish) were brought up in these hauls.  In addition, some interesting species of fish (see this blog’s Trawling Zoology segment below) were gathered in bottom trawls.

Miscellaneous Invertebrates from Bottom Trawl
Miscellaneous Invertebrates from Bottom Trawl
Large Lingcod Caught in Bottom Trawl
Large Lingcod Caught in Bottom Trawl

Using the Methot Trawl

We use the Methot trawling net to sample krill, a type of zooplankton that pollock feeds on.  On this voyage, the Methot was used 6 times as well.  The Methot is a single net with a large square opening or mouth. The net is deployed from the stern and towed behind the vessel.  Inside the Methot is a small removable codend where much of the catch is deposited.

Methot Net Lying on Trawl Deck
Methot Net Lying on Trawl Deck
Raising the Methot Net
Raising the Methot Net
Codend of Methot Overflowing with Krill
Codend of Methot Overflowing with Krill

The krill is measured and counted as well.  First, the water is drained out, then it is weighed, and a small sample is weighed and counted.

Lining Up and Counting Krill
Lining Up and Counting Krill

Bottom trawls and Methot trawls are both important aspects of the pollock survey.

Personal Log

Accomplishment

Continuing with Maslow’s hierarchy of needs, I will discuss the top part of the pyramid, how self-actualization, or being involved in creative endeavors to expand one’s full potential, are met on the Oscar Dyson.  

A Version of Maslow's Hierarchy of Needs
A Version of Maslow’s Hierarchy of Needs

Since I am an honorary member of the am science team, I am privy to many discussions between the scientists on the team regarding a variety of topics.   For example, one side project on the mission is to gather information regarding the abundance and distribution of euphausiids (krill) in the Gulf of Alaska.  This research project involves the use of a smaller “critter camera,” engineered and built by two of the MACE (Midwater Assessment and Conservation Engineering) group members, to take pictures of krill at various ocean depths and (ideally) reconcile its distribution with acoustic and Methot trawl data.  The goal of the project is to provide insight into the feeding conditions of pollock.  The discussions between group members involve postulating, speculating, testing, theorizing, analyzing, teaching, and questioning; clearly this meaty dialog  indicates that the process of science is an intellectually stimulating and creative endeavor.

Scientist Team Members--- Abigail, Patrick, and Kirsten---Engaged in a Stimulating Discussion
Scientist Team Members— Abigail, Patrick, and Kirsten—Engaged in a Stimulating Discussion
Did You Know?
One of the people who views my blogs before they are posted is the Executive Officer (2nd in Charge) of the crew on the Oscar Dyson.  His name is Chris and on this mission he is “augmenting” or filling in for another employee.  Chris administers the day-to-day operations of the crew including logistics, payroll, and travel.  Chris is a member of the NOAA Corps; he has both a BS in Marine Biology and an MS in Management Information Systems from Auburn University located in Auburn, Alabama.  He grew up in various places in the Midwest (his dad was in the U.S. Airforce) and has worked in several fields including information technology and zookeeping.  He applied to the NOAA Corps because he wanted to live and work near the ocean.
Chris, the Executive Officer of the Oscar Dyson
Chris, the Executive Officer of the Oscar Dyson

Something to Think About: 

In previous posts, we have explored invertebrates encountered on this mission. Today we will look at a group of vertebrates from the class  Osteichthyes, a word that comes from the Greek osteon meaning “bone” and ichthus meaning “fish.”  We will focus on some of the other fish besides pollock found in bottom trawls.  These bottom-dwellers are quite interesting creatures.

One of the most frequently found fish, other than pollock, is a type of rockfish called the Pacific Ocean Perch (POP); the species name is Sebastes alutus (Greek: Sebastes “August, venerable”, alutus “grow, nourish”).  This fish actually was seen in many trawls, both mid-water and bottom. As the picture below indicates, the body and fins of the POP are light red; however, there are dark olivaceous areas on back under soft dorsal fin and on the caudal peducle.  The maximum length of the fish is 55 cm and it is commonly found at a depth between 100-350 m.

Pacific Ocean Perch (a type of Rockfish)
Pacific Ocean Perch (a type of Rockfish)

A fish that belongs to the same genus as the POP is the Tiger Rockfish, Sebastes nigrocinctus ( Latin: niger, “black” and cinctus, “belt”).  We found this fish once in a bottom trawl.  The bottom of the tiger rockfish is light red to orange with several broad, vertical black-red bands on body.  It grows to a maximum length of 61 cm and is commonly found at a depth between 55 to 274 m.  Notice how similar it looks to the POP.

Tiger Rockfish, notice the similarities to the Pacific Ocean Perch
Tiger Rockfish, notice the similarities to the Pacific Ocean Perch

One of the most colorful fish that was found in a bottom trawl was the kelp greenling, Hexagrammos decagrammus (Greek:  hexa, “six”; grammus, “letter, signal”, deca, “ten”), a fish that generally hangs out in rocky reefs and kelp beds in relatively shallow waters (up to 46 m).  The fish is olive brown to bluish grey, speckled with irregular blue spots if male and reddish brown to gold spots if female (those we caught were most likely female).  The fish reach a maximum length of 53 cm.

Kelp Greenling
Kelp Greenling
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Amie Ell: Deadman’s Bay, July 11, 2013

NOAA Teacher at Sea
Amie Ell
Aboard NOAA Ship Oscar Dyson (NOAA Ship Tracker)
July 7 – July 11, 2013

Mission: Alaska Walleye Pollock Survey
Geographical Area: Gulf of Alaska
Date: July 11th, 2013

Location Data from the Bridge:
Latitude: 56.56 N
Longitude: 152.74 W
Ship speed:   11.3 kn

Weather Data from the Bridge:
Air temperature: 10.7 degrees Centigrade
Surface water temperature: 8.6 degrees Centigrade
Wind speed:  18 kn
Wind direction: 250 degrees
Barometric pressure: 1016 mb

Science and Technology Log:

Nets on Spools
Nets on Spools
OLYMPUS DIGITAL CAMERA
Full net on deck
OLYMPUS DIGITAL CAMERA
Pollock from a bottom trawl

So now that you know what we do with the fish after they are caught, let’s go back and see how the fishermen trawl.  There are two large nets at the stern of the ship.  Today we used both nets for the first time.  The scientists, crew, and fishermen all work together to catch the fish.  In the acoustics lab Paul is reviewing and scrutinizing the data he receives from the echo locators mounted on the hull of the ship.  There are many factors he must evaluate in order to have a good trawl.  There are places in our area that have been marked as “untrawlable”.  This is usually due to a sea floor that is rocky.  Trawling in these places may ruin the nets.  We have completed at least one trawl a day since we have been out to sea.  Today we completed two during my watch.  The first was with a larger net and was not sent all the way to the bottom.  The second trawl was sent to the bottom with a smaller net.  The bottom trawl brought up the largest pollock I have seen so far.  The longest pollock was 75 cm.  We also brought up a salmon, cod,   rock fish, and a whole lot of herring.

Crane lifting the net to be dumped into the bin.
Crane lifting the net to be dumped into the bin.
OLYMPUS DIGITAL CAMERA
The CamTrawl being removed after a trawl.

The nets are both on large spools and are released or returned with the help of a very large winch.  Before the net is released into the water the CamTrawl is attached to it.  This is a camera that takes pictures that help the scientists see at what point in the trawl fish were entering the net.

Example photo from the CamTrawl. A Salmon Shark caught on the first leg.
Example photo from the CamTrawl. A Salmon Shark caught on the first leg.

The time that the net is in the water depends on the information about the amount of fish coming from the acoustics lab.  Scientists watch the echo information to determine how much time the net should be in the water to catch enough fish to sample.  We must have at least 300 pollock to make a complete survey.

The fishermen bring the nets back to the trawl deck and wind them back onto the spools.  They then will use a crane to lift the catch and dump it into a bin.  From the fish lab we can lift this bin to dump the fish onto the conveyor belt.

Personal Log

Me in my survival suit
Me in my survival suit
Entering Deadman's Bay
Entering Deadman’s Bay

On Monday, we had our weekly fire and abandon ship drills.  After the drills I practiced putting on my survival suit.  This suit is designed to keep you afloat and warm in the event that you have to go into the water.

Deadman's Bay
Deadman’s Bay

On Tuesday, we surveyed up into Deadman’s Bay.  It was a beautiful sun shiny day and the scenery was amazing.  We were very close to the shore on both sides.  I sat out on the trawl deck and scanned the hillsides with my binoculars.  I was told that it is common to see bears here, but I did not see any.

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Johanna Mendillo: Nets, Northern Sea Nettles and More…, August 5, 2012

NOAA Teacher at Sea
Johanna Mendillo
Aboard NOAA ship Oscar Dyson
July 23 – August 10

Mission: Pollock research cruise
Geographical area of the cruise: Bering Sea
Date: Sunday, August 5, 2012

Location Data
Latitude: 61º 10′ N
Longitude: 179º 28’W
Ship speed: 4.3 knots ( 4.9 mph)

Weather Data from the Bridge
Air temperature:  11.1ºC (52ºF)
Surface water temperature: 8.1ºC (46.6ºF)
Wind speed: 5.4 knots ( 6.2 mph)
Wind direction: 270ºT
Barometric pressure: 1013 millibar ( 1.0 atm)

Science and Technology Log:

So far, you have learned a lot about the pollock research we conduct on board.  You have learned:

  • How to age fish (with otoliths)
  • How to measure fish (with the Ichthystick)

and

  • How to identify fish gender (with your eyes!)

Now, we are going to backtrack a bit to the two big-picture topics that remain:

  • How do we CATCH the pollock (hint hint, that is today’s topics… NETS!)

and

  • How do we even find pollock in the Bering Sea (that is the next blog’s focus: acoustics!)

So, to begin, there are several types of nets we are carrying on board.  Remember, when a net is dragged behind a ship in the water it is called trawling, and the net can be considered a trawl.  The most-used is the Aleutian Wing Trawl, or AWT, which we use to sample the mid-water column (called a midwater trawl).  We are also using a net called the 83-112, which is designed to be dragged along the ocean floor as a bottom trawl, but we are testing it for midwater fishing instead.  In fact, sometimes during my shift we do one AWT trawl, and immediately turn around and go over the same area again with the 83-112 to see differences in the fish sizes we catch!

If the 83-112, which is a smaller net, proves to be adequate for midwater sampling, NOAA hopes it can be used off of smaller vessels for more frequent sampling, especially in the years the NOAA does not conduct the AWT (NOAA currently does AWT surveys biennially).

Now, for each type of net, there is some new vocabulary you should know:

A typical midwater trawl
A typical midwater trawl…

The codend is the bottom of the net.  A closed codend keeps the fish inside the net and an open cod end allows them to swim through.  It may seem odd, but yes, sometimes scientists do keep the codend open on purpose!  They do this with a camera attached to the net, and they simply record the numbers of fish traveling through a certain area in a certain time period, without actually collecting them!  Here on the Dyson, the NOAA team is testing that exact type of technology with a new underwater camera called the Cam-Trawl, and you will learn about it in a later post.

The headrope is the top of the opening of the net.

The footrope is the bottom of the opening of the net.

(The 83-112 is called such because it has an 83 ft headrope and an 112 ft footrope.)

The trawl doors are in front of the headrope and help keep the net open.  Water pressure against the trawl doors pushes them apart in the water column during both setting of the net and while trawling, and this helps spread out the net so it maintains a wide mouth opening to catch fish.

There are floats on the top of the net and there can be weights on the bottom of the net to also help keep it open.

Lastly, the mesh size of the net changes: the size at the mouth of the net is 3 meters (128in.), and it decreases to 64in., 32in., 16in.., 8in., etc. until it is only ½ inch by the time you are holding the codend!

Here is a diagram to put it all together:

Courtesy of Kresimir Williams, NOAA

If you think about the opening of the net in terms of school buses, it will help!  It turns out that the AWT’s opening height, from footrope to headrope, is 25m, which is 2 school buses high!  The AWT’s opening width, is 40m across, about 3.5 school buses across!  Now, you can see why positioning and maneuvering the net takes so much care– and how we can catch a  lot of pollock!

Here is a trawl returning back to the ship's deck!
Here is a trawl returning back to the ship’s deck!

Now, when the scientists decide it is “time to go fishing” (from acoustic data, which will be the topic of the next blog) they call the officers up on the Bridge, who orient the ship into its optimal position and slow it down for the upcoming trawl.  Meanwhile, the deck crew is preparing the net.  The scientists then move from their lab up to the Bridge to join the officers– and they work together to monitor the location and size of the nearby pollock population and oversee the release and retrieval of the net.

Along the headrope, there are sensors to relay information to the Bridge, such as:

  • The depth of the net
  • The shape of the net
  • If the net is tangled or not
  • How far the net is off the bottom and
  • If fish are actually swimming into the net!

The fish and the net are tracked on this array of computer screens.  As the officers and scientists view them, adjustments to the net and its depth can be made:

The Bridge!
The Bridge!

The start of the trawl is called “EQ” – Equilibrium and the end of the trawl is called “HB” – haul back.  The net can be in the water anywhere from 5-60 minutes, depending on how many fish are in the area.

The AWT will get would up on this new reel
The AWT will get wound up on this reel

Now, sometimes an AWT catches so many fish that there are simply too many for us to measure and process in a timely fashion, so it is deemed a “splitter”!  In a splitter, there’s an extra step between hauling in the net from the ocean and emptying it to be sorted and processed.  The codend of the AWT is opened over a splitting crate, and half of the pollock go into a new net (that we will keep and sort through) and the rest of the pollock are returned to the water.

The net is back on board! Time to open up the codend and see what we have caught!
The net is back on board! Time to open up the codend and see what we have caught!

Personal Log:

Let’s continue our tour aboard the Oscar Dyson!  Follow me, back to the bridge, where the OOD (Officer on Duty) is at the helm.  As you already know, the first thing you notice on the bridge is the vast collection of computer screens at their disposal, ready to track information of all kinds.  You will learn more about these in an upcoming blog.

Busy at work on the bridge...
Busy at work on the Bridge…

In addition to these high-tech instruments, I was very happy to see good old-fashioned plotting on a nautical chart.  In class, students, you will have a special project where you get to track the changing position of the Oscar Dyson!

This chart is showing the northernmost point of three of our sampling transects- including the one closest to Russia!
This chart is showing the northernmost point of three of our sampling transects- including the one closest to Russia!

Here is a sample of the hour-by-hour plotting, done by divider, triangle, and pencil:

Can you spot them, hour by hour?
Can you spot them, hour by hour?

I will end here with a sea specimen VERY different from pollock, but always a fan favorite— jellyfish!  Interestingly, there are a large number of jellyfish in the Bering Sea- something I never would have assumed.  The one that we catch in almost every net is the Northern Sea Nettle (Chrysaora melanaster).  In one net, we collected 22 individuals!

When we collect non-pollock species such as these, we count, weigh, and record them in the computerized database and then release them back into the ocean.  Here they are coming down the conveyor belt after the net has been emptied:

Processing a net with many a jelly!
Processing a net with many a jelly!

The so-called bell, or the medusa, can be quite large- some are the diameter of large dinner plates (45cm)!  Their tentacles can extend to over 3m in length.  They consume mostly zooplankton, small fish (including juvenile pollock), and other jellies.  How so, exactly?  Well, when the tentacles touch prey, the nematocysts (stinging cells) paralyze it.  From there, the prey is moved to the mouth-arms and finally to the mouth, where it’s digested.

Some of the larger ones!
Some of the larger ones!

This same mechanism is used by sea nettle when it encounters danger like a large predator.  It stings the predator with its nematocysts and injects its toxins into its flesh.  In the case of smaller predators, this venom is strong enough to cause death.  In larger animals, however, it usually produces a paralyzing effect, which gives the sea nettle enough time to escape.

Now in the case of me handling them… and other humans…their sting is considered moderate to severe.  In most cases, it produces a rash, and in some cases, an allergic reaction.  However, we wear gloves on board and none of the scientists have ever had an issue holding them.  In fact, they offered to put one on my head and take a picture… but I declined!  If a few students email me, begging for such a picture, maybe I will oblige…

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Stacey Jambura: Not Your Average Fish Tail Tale July 16, 2012

Stacey Jambura
July 6 – 17, 2012
.
Geographical Area of Cruise: Gulf of Mexico
(You can view the NOAA ShipTracker here: http://shiptracker.noaa.gov/shiptracker.html)
Date: July 16, 2012
.
Weather Details from Bridge: (at 15:45 GMT)
Air Temperature: 28.8 ◦C
Water Temperature: 28.80 ◦C
Relative Humidity: 70 %
Wind Speed: 8.56 kts
Barometric Pressure: 1,017.68 mb

.

Science and Technology Log

The Trawling Net

Trawling Net
Trawling Net

The trawling net is used to collect groundfish samples. It is deployed from the stern of the ship and towed for 30 minutes. The net is towed back in and brought onboard to be emptied. During this process it is important that everyone at the stern of the ship is wearing a hard hat and a personal flotation device in the unlikely event that something goes wrong. Once the net is lifted over the side of the ship and brought on deck, it is untied and emptied into large baskets.

Hauling the trawling net back onboard.
Hauling the trawling net back onboard.

The baskets are weighed before they are brought inside and emptied onto a large conveyor belt. The fish are spread out on the belt so they are easier to sort. The fish are sorted into individual baskets by species. Once all of the fish are sorted, we count them and find their total weight. We then work through each basket and measure, weigh, and identify the sex of each specimen. Once we are done measuring the fish, some are bagged, labeled and frozen for scientists to examine back at their labs. The rest of the fish are thrown back into the ocean.

Emptying the trawling net into baskets
Alex & Reggie emptying the net into baskets.

We found many different species of vertebrates and invertebrates (fish with a spine, and those without a spine). Here are some of the fish we found:

Vertebrates

Invertebrates

It is important to document the length and weight of each fish collected in a trawl. We used special measuring boards and scales to collect this data. There are two boards, each is connected to one computer. When we measure the fish, we use a magnetic wand. When it touches the board, it sends a signal to the computer which records the length of the fish. Fish are measure at one of three lengths: fork length, standard length, and total length. Once the fish are measured, they are placed on a scale to be weighed. The scale is also connected to the computer and records the weight of the fish.

Scale
Scale
Boards
Measuring Boards
Fork length is measured from the inside of the tail of the fish.
Fork length is measured from the inside of the tail of the fish.
Standard length is measure from the base of the tail of the fish.
Standard length is measure from the base of the tail of the fish.
Total length is measured from the tip of tail of the fish.
Total length is measured from the tip of tail of the fish.

Personal Log

Day 12 – July 16th

Today is my last day at sea before we dock in Pascagoula,Mississippi. It has been quite a journey and I can’t believe it is already over. Though the work was hard and hot (and many times smelly), it was an amazing experience and I hope to one day have the opportunity to experience it again! I have met many wonderful people and hope to keep in touch with them! I have learned so much about our oceans and the life within them. I hope that my blogs have given you a glimpse into what life onboard the Oregon II is like and I hope that you have learned something about the work that takes place on the open seas.

Map of our Survey
Map of our Survey

Although this is my last day on the Oregon II, keep an eye out for one final blog. There will be interviews with the crew of the Oregon II, what their job is, why they chose this line of work, the steps they took to become a crew member of the Oregon II, and words of advice for students everywhere!

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Amanda Peretich: More Trawling Treasures, July 11, 2012

NOAA Teacher at Sea
Amanda Peretich
Aboard Oscar Dyson
June 30, 2012 – July 18 2012

Mission: Pollock Survey
Geographical area of cruise: Bering Sea
Date: July 11, 2012

Location Data
Latitude: 58ºN
Longitude: 173ºW
Ship speed: 11.7 knots (13.5 mph)

Weather Data from the Bridge
Air temperature: 7.9ºC (46.2ºF)
Surface water temperature: 7.3ºC (45.1ºF)
Wind speed: 10.7 knots (12.3 mph)
Wind direction: 323ºT
Barometric pressure: 1007 millibar (0.99 atm, 755 mmHg)

Science and Technology Log
In a recent post, I talked about how one of the things we are doing on board the Oscar Dyson is trawling for fish. The video from that post showed what happens in the fish lab during a midwater trawl. Remember that there are two nets we have been using for a midwater trawl: first, the normal Aleutian Wing Trawl, or AWT, which catches plenty of pollock, but also the 83-112 to which adjustments are being made to use this bottom trawl net for midwater fishing. But what about using the 83-112 for its original purpose: bottom (or benthic) trawling?

Bottom Trawl

83-112 Bottom Trawl Net
The 83-112 net used for bottom trawls (and comparison midwater trawls on this ship).

I’ve been lucky enough to see two bottom trawls on this cruise, although neither of them were actually during my shift. My wonderful roommate Carwyn, one of the other scientists on board, came to tell me about the bottom trawls so I could see all the neat creatures from below! A bottom trawl is used when the pollock are swimming much lower in the water column for one reason or another, but in trying to catch them, there are always many more “trawling treasures” that find their way onto the fish table. The process is basically the same as a midwater trawl, except the 83-112 net is lower down in the water towards the bottom of the sea floor (hence the term bottom trawl). The net is also much shorter in length than the AWT using in midwater trawling.

DYK?: How do the scientists know exactly how far down the net is in the water column? One of the sensors attached to the net is called the SBE (Seabird) 39. This will measure the depth and temperature during the trawl and determine the average head rope depth (which is the top of the net) and average temperature during the trawl between EQ (equilibrium – start of the trawl) and HB (haul back – end of the trawl). The sensor is then uploaded on the computer and the data is used by the scientific party.

Headrope Haul 76
This plot is used to determine the average head rope depth and temperature during the trawl (between EQ and HB). Depth is measured in meters and temperature in degrees Celsius on the y-axis versus time on the x-axis.
Field Guides
Field guides to classify various species found in the Pacific Ocean.

I attempted to classify all of these great bottom trawl treasures, and discovered that this was way easier said than done. There are some books in the fish lab with photos and descriptions just of the species that may be found around the Alaskan waters, and it was incredibly difficult to nail down a specific species for most of the finds!

In the bottom trawl, we found things such as the Oregon hairy triton, an unidentified pretty purple star fish, pink shrimp, basket stars, sheriff’s star, halibut, crabs, pacific cod, sculpin, Pribilof snail, sea anemone, scallop, sponge, sea pens, arrowtooth flounder, flathead sole, chiton, and seaweed.

Enjoy the slideshow below with photos of the bottom trawl treasures (and an interesting fact or two about some of them) or click on the link to open it in a new window!

Bering Sea Bottom Trawl Treasures

Methot Trawl

Methot Net
Methot trawl net.

The other trawl we’ve done outside of the normal AWT (Aleutian Wing Trawl) midwater and 83-112 midwater comparison trawl is something called a methot trawl. This uses a completely different net because the others have mesh that is much too large to catch something so small. The methot net has very fine mesh and a hard square opening with a fixed height. The cod end (very end of the net) is actually a small white container because the organisms collected are so small. A methot trawl is done to collect euphausiids, otherwise known as krill. Sometimes other microscopic (small) organisms are collected as well, including jellies, salps, and amphipods, which must then be carefully sorted out.

DYK?: Krill are part of the phylum Arthropoda, which includes species with an exoskeleton and jointed legs such as spiders, crabs, insects, and lobsters. They are an important part of the ecosystem because these small, reddish-orange animals are a source of food for many larger animals.

Steps to process a methot trawl in the fish lab:
1. Dump contents of the hard cod end container into a large gray bin.
2. Remove any large jellyfish (and weigh those separately).
3. Rinse contents from the gray bin into the sieve to remove any water.
4. Using tweezers, sort through the small microscopic organisms on the sieve and remove anything that isn’t krill.
5. Weigh krill sample.
6. Collect a random subsample in a scoop and weigh it.
7. Count all of the krill in the subsample (yes, this is as tedious as it sounds!).

Processing a Methot
Processing a methot trawl: removing water with the sieve, sorting through all of the krill and pull out any amphipods, salps, or jellies with tweezers (to weigh separately).

Personal Log

Bowthruster
Heading down to check out the bowthruster on the Oscar Dyson!

It continues to be a little slow on the trawling during my shift, but that’s okay, because I was lucky enough yesterday to get a tour of some of the lower bridge levels from the 1st Assistant Engineer, Tony.

DYK?: There are 8 levels on the Oscar Dyson. They are numbered, starting from the topmost deck, as follows:
O4 – flying bridge
O3 – bridge
O2 – staterooms (CO, XO, chief scientist)
O1 – staterooms (scientists), CTD winch, FRB (fast rescue boat), Peggy D (boat), liferafts
1 – galley, labs (acoustics, chem, dry, fish)
2 – engineering (machinery, centerboard, oceanic winch, trawl winch, and more), staterooms (deck crew and then some)
3 – engineering (machinery, bilge/ballast, workshop, and more)
4 – bowthruster, transducer, fuel oil tanks, ballasting tanks

I plan to share some of the facts I learned related to chemistry and biology from this tour (and other things on board) in one of my next blogs, so be sure to look for all of the info on the generators, sea water purification, MSD, cathodic protection system, and more.

We did have two trawls yesterday (July 10) – the first was an AWT midwater trawl that had caught so many fish it was actually a “splitter”! In a splitter, there’s an extra step between hauling in the net and getting it to the table in the fish lab. The cod end of the AWT net is opened over a separate splitting crate, where there is another net underneath that will only take about half of the fish to release on the table. The rest are then returned to the water.

Splitting
Splitting an AWT midwater trawl that collected too many pollock.

We also had drills yesterday (these are required once a week) and after gaining permission from the bridge, I checked in to my muster station (which is in the conference room for the science party, away from all of the action) and then went and watched what everyone else on board does. When we have fire drills in school, the alarm sounds, we walk outside, and wait for the “all clear” before heading back in. When they have fire drills on the Oscar Dyson, they use a smoke machine to produce smoke, there is an on-scene crew (first responders), there may or may not be a “victim” involved, the hose team actually dresses out (with the help of another person on the alpha or bravo firefighting teams), and the fire hoses are actually used. It may seem like old hat to everyone else on board, but I found it incredibly interesting to watch!

Fire Drill
Fire drill (smoke in the oceanic winch room) on board the Oscar Dyson.

Following the fire drill, there was an abandon ship drill, where everyone on board grabs their survival suit, PFD, and heads to one of three life rafts (there are actually 6 on the ship). The CO had me stay up in the TV lounge so that my life raft (#5) wouldn’t have a “full muster” until they sent out a search party to find me. Just as there are two people on hose team in both alpha and bravo for the fire drill, people must go in pairs for the search party, so Patrick and Rick came and found me. I think some people thought I’d actually not heard the alarm (I was wearing headphones), but I was instructed to be up there! We will have one more day of drills before we get back to Dutch Harbor, so maybe I’ll actually don my bright orange survival suit, which other Teachers at Sea in the past have affectionately called the “gumby suit” (even though Gumby was green).

Animal Love
In yesterday’s AWT midwater trawl, we had a new visitor in the fish lab. Introducing the lumpsucker!

Lumpsucker
Me (left) and ENS Libby (right) showing some love for a lumpsucker (middle).

The lumpsucker is in the family Cyclopteridae, which is derived from Greek words that mean circle and fin in reference to their round-shaped pectoral fins. There is a sucker on the bottom of them, so when we put this little sucker in some sea water while we were processing the fish, he stuck himself to the bottom of the container! Lumpsuckers are poor swimmers, so they are mostly benthic, meaning they stay at the bottom of the sea floor. However, that doesn’t mean they are incapable of swimming (especially since this one was caught during a midwater trawl). We took some photos and tossed this little guy back to sea, so hopefully he makes it!

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Andrea Schmuttermair: Eager Anticipation from Land-locked Colorado, June 7, 2012

NOAA Teacher at Sea
Andrea Schmuttermair
Aboard NOAA Ship Oregon II
June 22 – July 3, 2012

Mission: Groundfish Survey
Geographical area of cruise: Gulf of Mexico (between Galveston TX and Pascagoula, MS)
Date: June 7, 2012

Personal Log (pre-cruise)

What does

      +     +       =   ?

That’s right! Ms. Schmuttermair is heading to sea this summer as a participant in NOAA’s Teacher at Sea Program!

Me and my forever hiking pal, Wesson

Hi! My name is Andrea Schmuttermair, and I am a 3-6 grade science teacher at The Academy in Westminster, CO.  I just finished up my first year in this position, and absolutely love engaging my students in important science concepts. Outside of the classroom, I can be found hiking, biking, and exploring the mountains of beautiful Colorado with my dog, Wesson.

Growing up in San Diego, CA, I would definitely consider myself an “ocean lover”. I grew up spending countless hours at the beach, checking out the sea life that washed up in the tide pools and snorkeling in La Jolla Cove. When I heard about the Teacher at Sea program, I knew it was right up my alley. Living in land-locked Colorado, I strive to bring both my love and knowledge of the ocean to my students. One of the most memorable teaching moments for me this year was seeing my 3rd graders have that “Aha!” moment when they realized what we do here in Colorado greatly affects our oceans, even though they are hundreds of miles away.

Now, in just a couple short weeks, I will  don my sea legs, leave dry land behind, and set sail on the Oregon II. The Oregon II, one of NOAA’s 11 fishery vessels, conducts fishery and marine research to help ensure that our fish population in the ocean is sustainable. Fishery vessels work with the National Marine Fisheries Service to provide important information about fish populations and what regulations about fishing practices need to be in place.

This summer, we will be conducting the summer groundfish survey, a survey that has been conducted for the past 30 years. This particular survey is conducted during the summer months between Alabama and Mexico. On this second leg of the survey, we will be sailing from Galveston, TX to the Oregon II’s home port of Pascagoula, MS.


What exactly is a groundfish survey, you ask? When I first received my acceptance letter, they informed me that this was the “critter cruise”, and I, being the critter lover, was thrilled! The main goal of this survey is to determine the abundance and distribution of shrimp by depth. In addition to collecting shrimp samples, we may also collect samples of bottomfish and crustaceans. It will also be important to collect meteorological data while out at sea. I am excited to see what kind of critters we pull up!

Ms. Schmuttermair LOVES critters, as seen here with Rosy the scorpion.

How will we be catching all of these critters and collecting data while out at sea? The Oregon II has a variety of devices to help collect information about the ocean, including bottom trawls and a CTD. The bottom trawl is a large net that is towed to collect shrimp and other bottom dwellers that will be sorted once the catch is brought aboard. A CTD (stands for Conductivity, Temperature, and Depth) is an instrument that can collect a wide variety of data, including temperature, salinity and oxygen content. I can’t wait to learn how some of these tools are operated!

What are my goals while out at sea?

  • To learn as much about the environment I am in as possible.
  • To ask the scientists plenty of questions about their research, and why collecting data is so important.
  • To take many pictures to bring back to my students
  • To get to know the crew on board, and how they came to work on the Oregon II
  • Not getting seasick!

Now it’s your turn: What would YOU like to know more about? Is it more about the animals we bring up in our trawls? Maybe it’s to learn more about life on the Oregon II, and specifications about this ship. Perhaps you’d like to know how to become a scientist with NOAA and work on board one of their many ships.  Leave your questions in the “Comments” section below (you are welcome to do this in any of my entries), and I’ll do my best to answer them!

Don’t forget to keep an eye out for the challenge questions, which from this point forward I will refer to as the “Critter Query”.

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Caitlin Thompson: Bottom Trawl, August 11, 2011

NOAA Teacher at Sea
Caitlin Thompson
Aboard NOAA Ship Bell M. Shimada
August 1 — 14, 2011

Mission: Pacific Hake Survey
Geographical Area: Pacific Ocean off the Oregon and Washington Coasts
Date: August 12, 2011

Weather Data from the Bridge

Lat. 48 degrees 07.0 N
Long. 125 degrees 13.7 W
Present weather: partly cloudy 6/8
Visibility: 10 n.m.
Wind direction: 335
Speed 10 kts
Sea wave height: 2-3 feet
Swell waves – direction: —
Swell waves – height: —
Sea water temperature: 15.0 degrees C
Sea level pressure: 1017.3 mb
Temperature – dry bulb: 15.8 degrees C
Temperature – wet bulb: 13.2 degrees C

Science and Technology Log

Third Wire FS70
The Third Wire FS70 provides an image of the net, shown as half circle, and the fish around it.

The big news is that we’re headed to port a day early. There was a electrical component failure in the engine system that converts the diesel power to electricity which powers the electrical motors that turn the propeller shaft. This reduced the Shimada to running on about half power. I can’t believe the cruise is ending!

Yesterday we did a bottom trawl, the first bottom trawl ever conducted on the Shimada. Using the sonars, the scientists on the sonar team saw an interesting aggregation of fish. They couldn’t use the usual mid-water net, which is relatively easy to damage, because the fish were very close to the bottom. Besides, the bottom appeared hard and rocky. I was excited when they decided to test the new net. Unlike the mid-water trawls, which usually bring up a mostly “clean” haul of hake, a bottom trawl tends to bring up a wide array of species. I wanted to learn some new names.

ITI
The ITI shows the distance of the bottom of the ocean from the net. Where the pink lines are highest, the net is lowest.

Deploying the bottom net proved educational. The mid-water net is sent down with the FS70 attached, which provides an image of the objects near and in the net. On the screen shot of the FS70 above and to the right, look for the half-circle, which shows the open net, the silver blue line under the net, which is the bottom of the ocean, and some dots inside the net that are most likely fish already caught in the net. The images are sent through a wire. It would be too easy to damage the wire in a bottom trawl, so the scientists use the ITI instead.

Larry was in charge of fishing today and was disatisfied with the image the ITI System produced of the bottom trawl. The ITI does not produce as good an image of the bottom trawl as the FS 70 did on the midwater trawl. This made it more difficult to decide how much was being caught and how long to fish. The scientists began planning how to get a better system for the ship.

The bottom trawl disappointed the scientists because it brought up fewer hake than they had hoped, but I was happy to see so many new kinds of fish, and to learn to identify many so that I could help sort. This is the list of everything we pulled up:

Ratfish
This spotted ratfish has a venomous spine on its dorsel fin!
Aspot prawn, full of eggs
A spot prawn, full of eggs
Rockfish
Larry, Alicia and I sort rockfish. Initially, the fish on the table looked the same to me, but I soon learned to identify ...
Rex sole
Rex sole

Arrowtooth flounder
Brown cat shark egg case
Cloud sponges
Darkblotched rockfish
Dover sole
Greenstriped rockfish
Hermit crab unident.
Lanternfish unident.
Long honred decorator crab
Longnose skate
Pacific hake
Pacific ocean perch
Pom pom anemonome
Redbanded rockfish
Rex sole
Rosethorn rockfish
Sablefish
Sea cucumber unident.
Sea urchins and sand dollars unident.
Sharpchin rockfish
Shortspine thornyhead
Skate egg case ulnident.
Slender sole
Snail unident.
Spot prawn
Spotted ratfish
Wattled eelpout

Personal Log

Last night, some of us went up to the fly bridge in hopes of seeing the Perseid Meteor Shower. The sky was miraculously clear but the nearly full moon and bright lights on the ship blocked out most of the stars. Still, we saw some truly magnificent shooting stars before the clouds rolled in. I had brought my sleeping bag for warmth and fell fast asleep to the soothing voices of my shipmates. When they woke me up, I dropped by the chemistry lab to see how the nighttime zooplankton sampling was going and discovered that a mallard had arrived on deck. Mallards are not sea birds and are not equipped to be so far out to sea, so we were highly surprised to see her some fifty nautical miles off land. We named her Myrtle. We gave Myrtle food and water and hoped she would stay with the ship until we were close to land, but after a long nap, she took off. I hope she makes it to land.

In cribbage news, I won the semi-finals but lost the championship game. I had such a great time playing.

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Jason Moeller: June 23-24, 2011

NOAA TEACHER AT SEA
JASON MOELLER
ONBOARD NOAA SHIP OSCAR DYSON
JUNE 11-JUNE 30, 2011

NOAA Teacher at Sea: Jason Moeller
Ship: Oscar Dyson
Mission: Walleye Pollock Survey
Geographic Location: Gulf of Alaska
Date: June 23-24, 2011

Ship Data
Latitude: 54.86 N
Longitude: -161.68 W
Wind: 12.1 knots
Surface Water Temperature: 8.5 degrees C
Air Temperature: 9.1 degrees C
Relative Humidity: 95%
Depth: 52.43 m

Personal Log

As I mentioned in the last post, everything here has settled into a routine from a personal standpoint, and on that end there is not much to write about. However, there were three things that broke up the monotony. First, as always, the scenery was beautiful.

Cove
Snow covered hills shield the cove from the winds. Look how smooth the ocean is!
cove2
The view off the back of the ship.

Second, I found out that even with all of the modern equipment on board, catching fish is still not guaranteed. We trawled three times last night on the 23rd and caught a total of 14 fish in all three trawls! Remember, a good sample size for one trawl is supposed to be 300 pollock, so this is the equivalent of fishing all day long and catching a minnow that just happened to swim into the fishing hook.

The first trawl caught absolutely nothing, as the fish dove underneath the net to escape the danger. The second trawl caught two pacific ocean perch and one pollock, and the third trawl caught eleven pollock. All in all, not the best fishing day.

pollock
The lone pollock from the second trawl.

Despite the poor fishing, we did bring up this neat little critter.

isopod
This is an isopod! These animals are very similar to the pillbugs (roly-polys) that we find in the US. Many marine isopods are parasites, and can be a danger to fish!
isopod2
This is the bottom view of an isopod

The third thing to break up the monotony was the Aleutian Islands earthquake. On the evening of June 23rd, a magnitude 7.2 earthquake shook the Aleutian Islands. According to ABC news, the earthquake was centered about 1,200 miles southwest of Anchorage. The quake spawned a brief tsunami warning that caused a large number of Dutch Harbor residents (Dutch Harbor is the home base of the show Deadliest Catch) to head for higher ground. We had been in the Aleutian Islands and Dutch Harbor area on our survey route, but had left two days before, so the Oscar Dysonwas completely unaffected by the earthquake.

Dutch Harbor residents seek higher ground after a tsunami warning was issued. AP photo by Jim Paulin.

Science and Technology Log

In order to obtain photos of all of this neat sealife, we first have to catch it! We catch fish by trawling for them. Some of you may not know exactly what I’m talking about, so let me explain. Trawling is a fishing method that pulls a long mesh net behind a boat in order to collect fish. Trawling is used to collect fish for both scientific purposes (like we’re doing) and also in commercial fishing operations. We have two types of fish trawls onboard the NOAA Ship Oscar Dyson — a mid-water trawl net and a bottom trawl net. We’ve used both types throughout our cruise, so let me tell you a little about each.

The mid-water trawl net is just as it sounds — it collects fish from the middle of the water column — not those that live on the seafloor, not those that live at the surface. The technical name for the net we have is an Aleutian Wing Trawl (AWT) — it’s commonly used by the commercial fishing industry.

trawl net
Part of the mid-water trawl net as it's being deployed.

The end of the net where the fish first enter has very large mesh, which is used to corral the fish and push them towards the bag at the end. The mesh gets progressively smaller and smaller the further into it you go, and at the very end (where the collecting bag is), the mesh size is 0.5 inches. The end (where the bag is, or where the fish are actually collected) is called the codend.

codend
One of the codends on the deck of the Oscar Dyson

This is the kind of net we use when we want to collect a pollock sample, because pollock are found in the water column, as opposed to right on the seafloor (in other words, pollock aren’t benthic animals). Our particular net is also modified a little from a “normal” AWT. Our trawl has three codends (collecting bags) on it, each of which can be opened and closed with a switch that is controlled onboard the ship. The mechanism that opens and closes each of the 3 codends is called the Multiple Opening and Closing Codend (MOCC) device. Using the MOCC gives us the ability to obtain 3 discrete samples of fish, which can then be processed in the fish lab.

MOCC
The MOCC apparatus, with the 3 nets extending off.
bar
The nets are opened and closed using a series of metal bars. (The bar here is the piece of metal running across the middle of the photo). The net has 6 of these bars. When the first bar is released, the first codend is ready to take in fish. When the second bar is dropped, the first codend is closed. The third and fourth bars open and close the second codend, and the fifth and sixth bars open and close the third codend.
trigger
This is the trigger mechanism for the codends on the MOCC. When the codend is released, the trigger mechanism is up. When the codend is locked and ready to go, it is in the down position.

One other modification we have on our mid-water trawl net is the attachment of a video camera to the net, so we can actually see the fish that are going into the codends.

camera
This is the camera apparatus hooked up to the trawl.

When we spot a school of fish on the acoustic displays, we then radio the bridge (where the captain is) and the deck (where the fishermen are) to let them know that we’d like to fish in a certain spot. The fishermen that are in charge of deploying the net can mechanically control how deep the net goes using hydraulic gears, and the depth that we fish at varies at each sampling location. Once the gear is deployed, it stays in the water for an amount of time determined by the amount of fish in the area, and then the fishermen begin to reel in the net. See the videos below to get an idea of how long the trawl nets are — they’re being reeled in the videos. Once all of the net (it’s VERY long — over 500 ft) is reeled back in, the fish in the codends are unloaded onto a big table on the deck using a crane. From there, the fish move into the lab and we begin processing them.

Videos of the net being reeled in and additional photos are below!

http://www.youtube.com/watch?v=I50Q4SJzzaE
http://www.youtube.com/watch?v=VVAqbAGcxRs

net end
This is the end of the trawl net. They are lines that basically hold onto the net.
codend
One of the codends before being opened up onto the conveyor belt. We are inside waiting for the fish to arrive.
open codend
Opening the codend to release the fish catch!
reeled in
The mid-water trawl net all reeled in!

The other type of trawl gear that we use is a bottom trawl, and again, it’s just as it sounds. The bottom trawl is outfitted with roller-type wheels that sort of roll and/or bounce over the seafloor. We use this trawl to collect benthic organisms like rockfish, Pacific ocean perch, and invertebrates. There’s usually a random pollock or cod in there, too. The biggest problem with bottom trawls is that the net can sometimes get snagged on rocks on the bottom, resulting in a hole being ripped in the net. Obviously, we try to avoid bottom trawling in rocky areas, but we can never be 100% sure that there aren’t any rogue rocks sitting on the bottom 🙂

bottom trawl
The mesh and wheels of the bottom trawl.
btrawl2
More of the bottom trawl
btrawlreel
The bottom trawl, all reeled in!

Species Seen

Northern Fulmar
Gulls
Pollock
Pacific Ocean Perch (aka rockfish)
coral
Isopod

Reader Question(s) of the Day!

The first question for today comes from Rich, Wanda, and Ryan Ellis! Ryan is in the homeschool Tuesday class at the Zoo.

Q. We looked up what an anemone was and we found it was some kind of plant. Is that correct?

A. Great question! The answer is both yes and no. There is a type of flowering plant called the anemone. There are about 120 different species, and they are in the buttercup family. For one example of the plant, look below!

Anemone Nemorosa
Anemone Nemorosa. Taken from pacificbulbsociety.org

The sea anemone, however, is not actually a plant but an animal! Anemones are classified as cnidarians, which are animals that have specialized cells for capturing prey! In anemones, these are called nematocysts, which have toxin and a harpoon like structure to deliver the toxin. When the nematocysts are touched, the harpoon structure injects the toxin into the animal that touches it.

Cnidarians also have bodies consist of mesoglea, a non living jelly like substance. They generally have a mouth that is surrounded by the tentacles mentioned above.

Anemone
The Anemone we found.

The second question comes from my wife Olivia.

Q. What has surprised you most about this trip? Any unexpected or odd situations?

A. I think the thing that has surprised me the most is the amount of down time I have had. When I came on, I assumed that it would be physical and intense, like the show Deadliest Catch, where I would spend my whole time fishing and then working on the science. I figured that I would be absolutely toast by the end of my shift.

While I have worked hard and learned a lot, I have quite a bit of down time. Processing a catch takes about one hour, and we fish on average once or twice a night. That means I am processing fish for roughly two hours at most, and my shift is twelve hours. I have gotten a fair amount of extra work done, as well as a lot of pleasure reading and movie watching.

As for unexpected and odd situations, I didn’t really expect to get your camera killed by a wave. Fortunately, I have been allowed to use the scientist camera, and have been able to scavenge photos from other cameras, so I will still have plenty of pictures.

Another technological oddball that I didn’t think about beforehand was that certain headings (mainly if we are going north) will cut off the internet, which is normally fantastic. It is frustrating to have a photo 90% downloaded only to have the ship change vectors, head north, and cut off the download, forcing me to redownload the whole photo.
I also didn’t expect that the fish would be able to dodge the trawl net as effectively as they have. We have had four or five “misses” so far because the fish will not stay in one spot and let us catch them. While the use of sonar and acoustics has greatly improved our ability to catch fish, catching fish is by no means assured.

Perhaps the biggest “Are you kidding me?” moment though, comes from James and David Segrest asking me about sharks (June 17-18 post). An hour after I read the question, we trawled for the first time of the trip, and naturally the first thing we caught was the sleeper shark. Also naturally, I haven’t seen a shark since. Sometimes, you just get lucky.

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Tammy Orilio, Trawl Gear, June 24, 2011

NOAA Teacher at Sea: Tammy Orilio
NOAA Ship Oscar Dyson
Mission: Pollock Survey
Geographical Area of Cruise: Gulf of Alaska
Date: 24 June 2011


Weather Data from the Bridge:
Latitude: 54.14 N
Longitude: -164.16
Wind Speed: 9.73 knots
Surface Water Temp: 7.0 degrees C
Water Depth: 92.75 m
Air Temp: 7.2 degrees C
Relative Humidity: 101%

Science & Technology Log:
I’ve been talking a lot about trawling for fish, and I realize that some of you may not know exactly what I’m talking about, so let me explain. Trawling is a fishing method that pulls a long mesh net behind a boat in order to collect fish. Trawling is used to collect fish for both scientific purposes (like we’re doing) and also in commercial fishing operations. We have two types of fish trawls onboard the NOAA Ship Oscar Dyson– a mid-water trawl net and a bottom trawl net. We’ve used both types throughout our cruise, so let me tell you a little about each.

The mid-water trawl net is just as it sounds- it collects fish from the middle of the water column- not those that live on the seafloor, not those that live at the surface. The technical name for the net we have is an Aleutian Wing Trawl (AWT)- it’s commonly used by the commercial fishing industry. The end of the net where the fish first enter has very large mesh, which is used to corral the fish and push them towards the bag at the end. The mesh gets progressively smaller and smaller the further into it you go, and at the very end (where the collecting bag is), the mesh size is 0.5 inches. The end (where the bag is, or where the fish are actually collected) is called the codend. This is the kind of net we use when we want to collect a pollock sample, because pollock are found in the water column, as opposed to right on the seafloor (in other words, pollock aren’tbenthic animals). Our particular net is also modified a little from a “normal” AWT. Our trawl has three codends (collecting bags) on it- each of which can be opened and closed with a switch that is controlled onboard the ship. The mechanism that opens and closes each of the 3 codends is called the Multiple Opening and Closing Codend (MOCC) device. Using the MOCC gives us the ability to obtain 3 discrete samples of fish, which can then be processed in the fish lab. One other modification we have on our mid-water trawl net is the attachment of a video camera to the net, so we can actually see the fish that are going into the codends.

The MOCC apparatus, with the 3 nets extending off.
The MOCC apparatus, with the 3 nets extending off.
Part of the mid-water trawl net as it's being deployed.
Part of the mid-water trawl net as it’s being deployed.
The camera apparatus hooked up to the trawl.
The camera apparatus hooked up to the trawl.

When we spot a school of fish on the acoustic displays, we then radio the bridge (where the captain is) and the deck (where the fishermen are) to let them know that we’d like to fish in a certain spot. The fishermen that are in charge of deploying the net can mechanically control how deep the net goes using hydraulic gears, and the depth that we fish at varies at each sampling location. Once the gear is deployed, it stays in the water for an amount of time determined by the amount of fish in the area, and then the fishermen begin to reel in the net. See the videos below to get an idea of how long the trawl nets are- they’re being reeled in in the videos. Once all of the net (it’s VERY long- over 500 ft) is reeled back in, the fish in the codends are unloaded onto a big table on the deck using a crane. From there, the fish move into the lab and we begin processing them.

The end of the trawl net. These are the lines that basically hold on to the net!
The end of the trawl net. These are the lines that basically hold on to the net!
The mid-water trawl net all reeled in.
The mid-water trawl net all reeled in.
One of the codends before being opened up.
One of the codends before being opened up.

The other type of trawl gear that we use is a bottom trawl, and again, it’s just as it sounds. The bottom trawl is outfitted with roller-type wheels that sort of roll and/or bounce over the seafloor. We use this trawl to collect benthic organisms like rockfish, Pacific ocean perch, and invertebrates. There’s usually a random pollock or cod in there, too. As I mentioned in my last post (“Today’s Catch”), the net can sometimes get snagged on rocks on the bottom, resulting in a hole being ripped in the net. Obviously, we try to avoid bottom trawling in rocky areas, but we can never be 100% sure that there aren’t any rogue rocks sitting on the bottom 🙂

The mesh and the wheels of the bottom trawl.
The mesh and the wheels of the bottom trawl.
More of the bottom trawl.
More of the bottom trawl.
The bottom trawl all reeled in.
The bottom trawl all reeled in.

Personal Log:
It’s been a quiet couple of days. On Wednesday, we didn’t see any fish until late in my shift, then we did a mid-water trawl. We ended up actually busting the bag- that’s how many fish we ended up collecting!! Once the codends were opened, we immediately began processing- first separating the pollock from everything else we caught. After sorting, I got to work on sexing the fish- it’s a kind of gruesome job, because you have to take a scalpel and cut them open (while they’re still alive!), exposing their innards- definitely NOT like the preserved organisms we dissect in class. I’m not a huge fan of cutting them open, so I moved on to measuring the length of the male fish- there were so many males in our catch, I was the last one working! After I cleaned up, that was the end of my shift. We were near some islands at the end of my shift, and the bridge called down to the lab to tell us that there some whales off the starboard side of the ship. I grabbed my camera and ran up to the deck, scanning the water for whales. Finally, I spotted a pod waaaay off the starboard side- they were too far off to get a good picture, and I couldn’t even tell what kind they were, but I was able to see them spouting water out of their blowholes, and it looked like one of them breached. The officers up on the bridge said they thought they were minke whales.

Thursday we didn’t see any fish (well, not enough to put our gear in the water) all day, so no fishing for me. Right now, it’s about 9:30 a.m. on Friday, and we’re just cruising to begin our next set of transects. I just read that there was an earthquake in the western Aleutian Islands last night- magnitude 7.2! Holy moly, I was just there! Apparently, people felt the earthquake as far east as Dutch Harbor on the island of Unalaska, and they had a tsunami warning go off. It’s crazy to think that I was in that area a couple days ago!

Question of the Day:

  • Speaking of tsunamis…What would cause the East Coast of the U.S. to be hit by a megatsunami?
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Tammy Orilio, Today’s Catch, June 21, 2011

NOAA Teacher at Sea: Tammy Orilio
NOAA Ship Oscar Dyson
Mission: Pollock Survey
Geographical Area of Cruise: Gulf of Alaska
Date: 21 June 2011

Weather Data from the Bridge:
Latitude: 54.25 N
Longitude: -163.31 W
Wind Speed: 13.56 knots
Surface Water Temp: 7.5 degrees C
Water Depth: 69.38 m
Air Temp: 6.8 degrees C
Relative Humidity: 95%

Personal Log:
We did our (well, my) first bottom trawl today. The trawl net is outfitted with rollers/wheels that ride over the seafloor while the net collects benthic (bottom-dwelling) organisms. One thing I talk about in Marine 2 is how bottom trawling is damaging to the environment, and we definitely saw that firsthand today- there were quite a few rocks brought up in the net along with the animals. The seafloor was not as flat as we had hoped- in fact, the net ended up with a 4-foot hole ripped in it, which the deckhands/lead fishermen sewed for us later on in the day. Now, in the case of bottom trawling to collect scientific data, I don’t have a problem…but in the case of doing it for profit, as in the case of commercial fishing operations, I can’t abide by that. I would probably feel a little different if ALL we were doing was bottom trawls, but we’ve only done 2 so far, so…that’s how I’m rationalizing it. What’s your take on this? Should scientists damage an environment and/or kill organisms just to collect scientific data? And just so you know, the data we’re collecting on this survey is not just sitting around, completely useless- we are using it to actually help manage fish populations and regulate commercial fishing. The limits that all commercial fishermen have- how much they can legally take- are determined by knowing the current population status, and we can only learn that by seeing what’s out there, where things are, their age, what they’ve been eating, etc etc.
Following are some pictures of the animals from today’s bottom trawl.

Black Rockfish- we had some fried rockfish for dinner tonight!
Black Rockfish- we had some fried rockfish for dinner tonight!
Cushion star- also called Slime Star b/c it secretes slime when it's disturbed...which I discovered today!
Cushion star- also called Slime Star b/c it secretes slime when it’s disturbed…which I discovered today!
Fanellia compressa- a soft coral- it's pinkish/peachish in color
Fanellia compressa- a soft coral- it’s pinkish/peachish in color
Atka mackerel
Atka mackerel

One last thing…we went by Unimak Island today- it’s the easternmost of the Aleutians, which means that we will soon be re-entering the Alaskan peninsula- but we’re still a long way from Kodiak 🙂 Unimak Island has an active volcano on it called Shishaldin, and we were able to see it today. Pretty awesome!

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Megan Woodward, July 10, 2009

NOAA Teacher at Sea
Megan Woodward 
Onboard NOAA Ship Oscar Dyson
July 1 – 18, 2009

Mission: Bering Sea Acoustic Trawl Survey
Geographical Area: Bering Sea/Dutch Harbor
Date: Tuesday, July 10, 2009

The pollock are carefully loaded onto the table.
The pollock are carefully loaded onto the table.

Weather/Location 
Position: N 56.30.202; W 172.34.37
Air Temp: 7.4 (deg C)
Water Temp: 7.4 (deg C)
Wind Speed: 19 knots
Weather: Overcast

Science and Technology 

Once the fish are onboard a rigorous data collection process begins.  All of the data collected are recorded via instruments linked to a computer network in the fish lab.  Below is a series of photos showing the process used in the fish lab to collect valuable data.

Once the fish are on the table, we carefully look through the fish for any species other than pollock caught in the trawl.  These non-pollock species are sorted into bins and accounted for. The fish are weighed one basket full at a time as they reach the end of the conveyor belt.  Initially, we take a count of how many fish fill one basket.  There is a scale connected to a computer program that records the basket’s weight.

The sorting begins. The pollock are sorted between male and female.
The sorting begins. The pollock are sorted between male and female.

After weighing the pollock, we move on to sorting a sample of approximately 300 fish by sex.  To find the sex of a fish we cut open its belly and look for either male or female reproductive organs. The sexed fish are then placed in the appropriate bin. Next, each pollock from the male/female sort is measured in centimeters.  We use a measuring board linked to a computer that records the size of each fish. There is a small tool in my hand that gets placed at the “v” of the fish tail.  Sensors on the board detect the placement of the measuring wand, and send a length measurement to the computer so it can be recorded.  This program also keeps track of how many fish we measure, so we get an accurate sample count.

The stomach of a pollock is prepared for preservation.
The stomach of a pollock is prepared for preservation.

Several scientists have asked us to collect pollock for various research projects. One project, designed to study the diet of pollock, requires us to sex, measure, weigh and take the stomach of 20 pollock from each haul. A label with all of the information is placed in a bag with the stomach.  They are placed in a freezer for preservation purposes.

Here I am using the measuring board. The stomach of a pollock is prepared for preservation.
Here I am using the measuring board.

We also use a similar process for scientists examining one-year-old pollock. This study asks for the entire fish to be preserved, not a specific organ. In one 12-hour shift there is a maximum of 3 trawls if fish sign is identified in the acoustics lab. Each trawl takes 2 to 3 hours to process. It’s possible another trawl could happen while finishing up the data collection from the previous haul. This makes for a very busy, fish filled shift.

Personal Log 

I was in charge of weighing the fish!
I was in charge of weighing the fish!

Working in the fish lab has provided for a tremendous amount of new learning to take place. I’ve learned to identify species of fish that mix in with pollock (capelin, flatfish, skate and cod), and have seen several crustaceans and jellyfish, too.  All of the measuring technology has been straight forward and user friendly. Sexing the fish has been the most difficult job, but has become easier with practice. Examining the innards to identify male or female reproductive organs seems nearly impossible in the young fish, and it’s not always clear in the older fish.

Today I was in charge of weighing the fish as they came down the conveyor belt. I was certainly mistaken when I thought it would be a simple task. First off, I had to count the fish as they dropped into the basket at a speed faster than I could count. At the same time I had to control the speed of the belt and open the gate so more fish would move down the line.  When the basket was full, I stopped the belt and placed the full (semi-accurately counted) basket on the scale and waited for the scale’s “steady” signal to come on.  Since the boat is constantly in motion the steady light rapidly blinks on and off. It took me three tries before I managed to get the basket weighed.  Meanwhile the rest of the team patiently waited.  Maybe I’ll give it another try tomorrow.

This average sized skate was flapping his wings making him difficult to hold. Look closely at the fish on the conveyor belt and you will see hermit crabs and seastars.
This average sized skate was flapping his wings making him difficult to hold. Look closely at the fish on the conveyor belt and you will see hermit crabs and seastars.
Basketstars were brought up in a bottom trawl. Hermit crabs and snails were also caught in the bottom trawl.
Basketstars were brought up in a bottom trawl.
Hermit crabs and snails were also caught in the bottom trawl.
Hermit crabs and snails were also caught in the trawl.

Animals Seen 

  • Minke Whale
  • Skate
  • Pacific Cod
  • Tanner Crab
  • Snow Crab
  • Basketstar
  • Sturgeon Poacher
  • Snails
  • Hermit Crabs
  • Arrow Tooth Flounder
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Ruth Meadows, July 5, 2009

NOAA Teacher at Sea
Ruth S. Meadows
Onboard NOAA Ship Henry B. Bigelow 
June 12 – July 18, 2009 

Mission: Census of Marine Life (MAR-Eco)
Geographical Area: Mid- Atlantic Ridge; Charlie- Gibbs Fracture Zone
Date: July 5, 2009

dumbo octopus
Dumbo octopus

Weather Data from the Bridge 
Temperature: 10.3o C
Humidity: 93%
Wind: 8.9 kts

Science and Technology Log 

Dr. Mike Vecchione holds a very large dumbo octopus from one of the deep sea trawls. This octopus got its name from the large fins that look like the ears of “Dumbo” the elephant. It is a benthic cephalopod (an ancient group in the phylum Mollusca) that lives above the floor of the ocean. It probably feed on copepods and other small crustaceans, but we don’t know much about its biology. This particular species (Cirrothauma magna) has only been caught a few times before.

a very large example of a slickhead
A very large example of a slickhead

John Galbraith and Tom Letessier hold a very large example of a slickhead. These fish are dark in color and their exterior is slippery. These soft-bodied soggy fish are common in waters greater than 1000m deep. They get their common name from the slimy look of their head. They lack a swim bladder and make themselves as light as possible by having weak bones and watery flesh. Chimeras are distantly related to sharks and rays and can be found at depths up to 2500m. These fish have cartilage instead of bones. We caught several of these in the benthic trawls, but this one was the largest.  Most of these fish have a venomous spine at the back of its dorsal fin.

This is a chimaera that weighed in at 12 kilograms.
This is a chimaera that weighed in at 12 kilograms.
Basti (from Germany) is holding another chimaera, Venda (from Portugal) has a slickhead and Meridith (from Boston) has a lizardfish from the last benthic trawl of the cruise.
Basti (from Germany) with a chimaera, Venda (from Portugal) has a slickhead and Meridith (from Boston) has a lizardfish.

Do You Know? 

What would happen between a shark and an octopus? Find out here.   

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Mandi Gillespie, July 6, 2007

NOAA Teacher at Sea
Mandi Gillespie
Onboard NOAA Ship Oregon II
July 5 – 7, 2007

Mission: Summer Groundfish Survey
Geographical Area: Gulf of Mexico
Date: July 7, 2007

NOAA ship OREGON II at port waiting to set sail.
NOAA ship OREGON II at port waiting to set sail.

Weather Data from Bridge 
Visibility: n/a
Wind direction:243
Wind speed: 6.7 kts
Sea wave height n/a
Swell wave height: n/a
Seawater temperature: 26.8 C
Sea level pressure: 1016 mb
Cloud cover: n/a

Science and Technology Log 

This cruise’s mission is two fold: 1) stock assessment of fish and invertebrates and 2) mapping of the hypoxia zone. To assess the fish and invertebrate stock, a 40-foot bottom trawl net collects bottom samples from designated sites. The samples are gathered, identified, measured and weighed by the scientists on board the ship. Data collected is eventually used to set bag limits for fish and shrimp. To measure the hypoxic zone, equipment is deployed from the ship at specific sites. Dissolved oxygen level is collected. This data is used to map the Gulf of Mexico’s hypoxic zone.

Personal Log 

I arrived onboard the OREGON II on July 4th eager to set sail. However, we have been delayed because the auxiliary emergency generator onboard will not start. Once the generator functions properly, we will be able to set sail.

My position title is watch stander and am told training for my position is “on the job”. I am scheduled on the day shift which is 12:00 to 24:00. I look forward to fulfilling my duties as a watch stander to better understand how the samples are collected and processed.

Question of the Day 

What is a hypoxic zone? 

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Jacob Tanenbaum, June 19, 2006

NOAA Teacher at Sea
Jacob Tanenbaum
Onboard NOAA Ship Miller Freeman
June 1 – 30, 2006

Mission: Bering Sea Fisheries Research
Geographic Region: Bering Sea
Date: June 19, 2006

Mountains in the clouds
Mountains in the clouds

Weather Data from the Bridge

Visibility: Less than 1 mile
Wind Speed: 14 miles per hour
Sea Wave Height: 2 feet
Water Temperature: 44.06 degrees
Air Temperature: 41.36 degrees
Pressure: 1018 Millibars

Personal Log

NOTE: We will arrive in the port of Dutch Harbor, Alaska on June 20. As the project draws to a close, I would like to evaluate how effective it was. There is a link to an electronic survey. I would like to ask students, teachers, parents, and other visitors to the site to take a few moments to let me know what you think of this idea. The survey is all electronic and only takes a minute or two to complete. Thank you in advance for your time. Click here to access the survey. I should be able to send one more blog tomorrow from Dutch Harbor. Check back and I will let you know what being on land again feels like. Dutch Harbor should be an interesting place.

Large sea stars from the bottom trawl
Large sea stars from the bottom trawl

We passed the Pribilof Islands. Home to one of the largest worlds largest gatherings of marine mammals in the summer time. I got up to see the islands at midnight and again when we passed a second one at 4:00 AM. We were covered in fog both times, so we will have to come back another day. At midnight, the sun had not yet set. Our sun set last night at about 12:15 and it took a long time to grow dark after that. The sky began to grow light at about 5:00 and it came up a little after 6. A short night.

Science Log

Last night we had another bottom trawl. This one had some of the largest sea stars I have ever seen. One was close to a foot long.  In addition, there is a coral here called sea raspberry. It is common along the Bering Sea Shelf. I thought coral was only in tropical seas, but here it is in the Bering Sea. Since it is our last day at sea, I spoke to our Chief Scientist Dr. Paul Walline from the Alaska Fisheries Science Center in Seattle Washington about what we have learned so far.

Coral called a sea raspberry
Coral called a sea raspberry

What does the data tell you so far? 

What do you expect to see in the next legs?

What will happen to the data at the end of the cruise? 

Finally, we were testing a platform today that can open nets at different depths. We lowered the platform to about 390 feet before a technical problem forced us to raise it back up to the surface. As an experiment of my own, I tied a bag of Styrofoam cups to the platform to see what the pressure at that depth would do to them. Want to see more? Click here for a video

Question of the Day:

What was your favorite part about participating in this project. Please write and let me know.

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Jacob Tanenbaum, June 18, 2006

NOAA Teacher at Sea
Jacob Tanenbaum
Onboard NOAA Ship Miller Freeman
June 1 – 30, 2006

Mission: Bering Sea Fisheries Research
Geographic Region: Bering Sea
Date: June 18, 2006

mike-781281Weather Data from the Bridge

Visibility: 10 miles
Wind Speed: 9 miles per hour
Sea Wave Height:2 feet
Water Temperature:41 degrees
Air Temperature:40.8 degrees
Pressure: 1013 Millibars

Personal Log

NOTE: We will arrive in the port of Dutch Harbor, Alaska on June 20. As the project draws to a close, I would like to evaluate how effective it was. There is a link to an electronic survey. I would like to ask students, teachers, parents, and other visitors to the site to take a few moments to let me know what you think of this idea. The survey is all electronic and only takes a minute or two to complete. Thank you in advance for your time. Click here to access the survey.

Sea cucumbers
Sea cucumbers

By now, you have met many of the interesting people aboard NOAA ship MILLER FREEMAN. There are three groups of people aboard these ships. The officers on the ship are part of the NOAA Corps. This is a uniformed service of the United States consisting of about 300 officers who complete rigorous training and hold ranks, like ensign, or commander. They are in charge of ships operations and stand watch on the bridge. The scientists aboard are mostly from NOAA research labs, like the Alaska Fisheries Science Center in Seattle. Many of the other members of the crew are civilian wage mariners. These are professional sailors who handle many of the day to day operations of the ship. Some, such as Chief Engineer Bus, have made their home on this ship for close to 30 years. Other sailors are contract workers who come aboard for a few months, go home and take a break, then join the crew of another ship for a different sort of cruise. Sometimes they are on research vessels, sometimes they are on freighters, sometimes they are on tankers. Today, lets meet able-bodied seaman, or AB Michael O’Neal. Click each question to listen to the answer.

Mud star
Mud star

What do you do on board the NOAA Ship MILLER FREEMAN?

Tell us about what you have done and where you have gone on some of the other ships you have been on.

Where are some of the other jobs you have had at sea?

What does it take to be an able-bodied seaman?

Science Log:

Smile! Here are big mouth sculpins. Once close up and one in the hands of Dr. Mikhail Stepanenko.
Smile! This is a big mouth sculpin.

We had another in a series of amazing bottom trawls last night. When the nets trawl along the bottom out here, some of the most interesting creatures of all get swept into our nets. Creatures that live on the bottom are often stranger looking for a few reasons. They are adapted to blend into the bottom so that predators cannot see them. They often wind up looking like rocks or plants as a kind of defense. They are also adapted to an environment with higher pressure and less light than the surface. Some of their adaptations can also make them look very different from other fish. Since they don’t have to worry about predators below them, these fish may be flat and have both their eyes sticking up. These creatures often do not need to be fast swimmers, since their defense is to blend into the environment rather than swim away when predators approach. The basket of sea cucumbers was one of the strangest things I’ve seen so far. These sticky blobs are not plants. They are sea creatures that live on the bottom of the sea and sift through the sand or water to find food. There are several different kinds of sea cucumbers in this basket. Can you see the different types? Mud stars, on the other hand, are soft and sticky, not like the sea stars we have at home. It may be called a mud star, but I think looks like Patrick from Sponge Bob.

Here is another kind of sculpin with large fins that look like the wings of a butterfly, called a Butterfly sculpin.
Another kind of sculpin with large fins that look like the wings of a butterfly, called a Butterfly sculpin.

Question of the Day

Now that you have seen some of the different jobs aboard NOAA Ship MILLER FREEMAN, if you were on a ship, which job would you prefer? Write me a comment on the blog and let me know!

Answer to Yesterday’s Question

Look at the movements of the ship described above. When the ship drives into the wind and waves, sailors call it a corkscrew motion. Can you think why?

A corkscrew motion occurs when the ship is struck by waves in such a way that it moves in several motions at once. In other words, it may pitch, roll, surge, and sway all at the same time. I’m getting a funny feeling in my stomach just thinking about it!

Answers to Your Questions

Sorry that I left off the link from Friday where you can see the position of the ship. Here it is. Fair warning, the site was down for most of today, so if it does not work, just try again later.

http://info.nmao.noaa.gov/shiptracker/Ship.aspx?ship=Miller%20Freeman

After we put in to port, I’ll have a day or two in Dutch Harbor to look around, before I can get a flight in to Anchorage. After that, I’ll be visiting some friends and family out west before I head back east. Thanks for writing. 

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Jeff Grevert, June 15, 2005

NOAA Teacher at Sea
Jeff Grevert
Onboard NOAA Ship Delaware II
June 8 – 16, 2005

Mission: Surf Clam Survey
Geographical Area: New England
Date: June 15, 2005

The dredge
The dredge

Weather Data

Latitude: 41° 12′ N
Longitude: 070° 45′ W
Visibility: 2 nm
Wind Direction: 220°
Wind Speed: 13 kts.
Sea Wave Height: 2 ft.
Swell Wave Height: 2 ft.
Sea Water Temp.: 13.3° C
Sea Level Pressure: 1007.9 mb
Cloud Cover: 5/8 (Altocumulus, Cirrus)

Science and Technology Log

0000- 0600: After one successful trawl, an electrical component on the dredge lost power. During the next four hours, scientists and engineers dismantled the component and realized that it had a leak which allowed water to enter. The component was most likely damaged when the dredge was dragged over rocks yesterday. The component was repaired by the end of my watch. We then went off watch and ate dinner. When I awoke for my next watch, I learned that the next watch (0600-1200) also experienced power loss to the component.  Again it had to be dismantled and repaired.

1200-1800 The dredge and all components worked smoothly for my second watch.  Our trawls yielded few clams however.  One trawl filled the dredge with nothing but benthic sediment.  After being relieved by the next watch I ate dinner and went to work on lesson plans and interviews.

grevert_log8a

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Jeff Grevert, June 14, 2005

NOAA Teacher at Sea
Jeff Grevert
Onboard NOAA Ship Delaware II
June 8 – 16, 2005

Mission: Surf Clam Survey
Geographical Area: New England
Date: June 14, 2005

Skates!
Skates!

Weather Data

Latitude: 40° 28′ N
Longitude: 69° 27′ W
Visibility: < 1nm
Wind Direction: 230°
Wind Speed: 12 kts
Sea Wave Height: 1 ft.
Swell Wave Height: 3 ft.
Sea Water Temp: 10.3° C
Sea Level Pressure: 1004.1 mb
Cloud Cover: 1/8 (Altocumulus)

0000- 0600 Went on watch. Conducted a few trawls which yielded ocean quahogs. Bycatch included little skates and starfish. At the end of my watch I ate breakfast and went to sleep.

1200-1800 Conducted more successful trawls. This was the first day that my watch had two uninterrupted watches.  We got a lot of work done and had good clam yields.  Interesting bycatch included a goosefish. Not knowing any better, my cabin mate stuck his hand in the goosefish’s mouth and got bitten.  At the end of my watch I ate dinner and went to work on my lesson plans.

On the next watch the dredge hit an underwater rock field and got mangled.  The crew and scientists successfully replaced the front blade assembly with a spare. This halted operations for a while but soon we were back to work.

The goosefish has sharp teeth!
The goosefish has sharp teeth!
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Jeff Grevert, June 13, 2005

NOAA Teacher at Sea
Jeff Grevert
Onboard NOAA Ship Delaware II
June 8 – 16, 2005

Mission: Surf Clam Survey
Geographical Area: New England
Date: June 13, 2005

Clam sizes
Clam sizes

Weather Data

Latitude: 41° 12′ N
Longitude: 070° 45′ W
Visibility: 2 nm
Wind Direction: 220°
Wind Speed: 13 kts.
Sea Wave Height: 2 ft.
Swell Wave Height: 2 ft.
Sea Water Temp.: 13.3° C
Sea Level Pressure: 1007.9 mb
Cloud Cover: 5/8 (Altocumulus, Cirrus)

Science and Technology Log

We’re back underway 🙂 The repairs went well and the Delaware II set sail at 1400 hours. It was about a three-hour steam to our first sampling station.  Once we arrived, there was time on my watch to conduct one trawl. Only one Ocean Quahog was collected. Some bycatch included sea stars, sponges, sand dollars and a crab. At 1800 hours I went off watch and ate dinner. Later I worked on my lesson plans and collected data from the ship’s weather log.  Currently I’m waiting for my second watch (midnight).  I think I’ll get some rest.

Taking measurements and collecting data
Taking measurements and collecting data

 

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Jeff Grevert, June 11, 2005

NOAA Teacher at Sea
Jeff Grevert
Onboard NOAA Ship Delaware II
June 8 – 16, 2005

Mission: Surf Clam Survey
Geographical Area: New England
Date: June 11, 2005

grevert_log4Weather Data
Latitude: 38 39 N
Longitude: 73 50 W
Visibility: < 0.5 nm
Wind Direction: 190
Wind Speed: 10 kts
Sea Wave Height: 2′
Swell Wave Height: N/A
Sea Water Temp: 15.8 C
Sea Level Pressure: 1021.4 mb
Cloud Cover: Fog

Our entire day was spent steaming en route to Woods Hole, MA. We arrived around 1600. Many of the scientists and crew dispersed to go home to their families.  No scientific research took place.

grevert_log4b

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Jeff Grevert, June 10, 2005

NOAA Teacher at Sea
Jeff Grevert
Onboard NOAA Ship Delaware II
June 8 – 16, 2005

Mission: Surf Clam Survey
Geographical Area: New England
Date: June 10, 2005

Sampling surf clams
Sampling surf clams

Weather Data
Latitude: 37° 51′ N
Longitude: 74° 25′ W
Visibility: 7 nm
Wind Direction: 182°
Wind Speed: 13 kts
Sea Wave Height: 2′
Swell Wave Height: N/A
Sea Water Temperature: 16.1° C
Cloud Cover: N/A, Clear

0000 – Went on watch.  Shortly after my watch started, we experienced generator issues.  The overhead lights in the science lab went out momentarily and we were on an emergency generator to keep the computers on.  Both generators are required to work the wench that controls the dredge, so operations ceased for approximately the next four hours. At around 0400 the ship’s engineers fixed the problem, and trawling continued.  The few trawls we were able to conduct yielded fewer shellfish than in previous days. The watch chief explained that it probably had to do with the location of those specific stations we were sampling in the vicinity of Delaware Bay. Bycatch included a stargazer fish (Astroscopus sp.) and a horseshoe crab (Limulus polyphemus).

Sorting baskets
Sorting baskets

0600 – Finished the assigned duties of my watch, ate breakfast, and went to sleep.

1200 – Went on watch.  We conducted one trawl with a small yield.  The catch included ocean quahogs (Arctica islandica) and several specimens of Chestnut Astarte (Astarte castanea). I must say that working with someone educated outside of the U.S. helps you to appreciate the value of binomial nomenclature.  Common names for the same organism are different all around, but the scientific name remains the same.

Soon after our first trawl, we experienced technical difficulties with the power pack that controls the wench which drives the sampling dredge weighing in at approx. 7,000 lbs (empty).  The ship’s engineers were unable to fix it with the present resources.  At this point, it was decided to turn around and head back to Woods Hole to obtain the parts necessary for repairs. We are currently on a 25hour trip back north from Delaware Bay to Woods Hole. After the power pack is repaired we will set out to continue sampling most likely in the vicinity of southern New England.

Since no sampling can take place, we are not standing watches at this time.  Most of the scientists are using this time for R&R by sleeping, listening to music, watching satellite TV, and viewing one of over 500 films on 8mm provided by the U.S. Navy Motion Picture Service.  Some of the films are still in theatres!  R&R is always nice, but I am eager to get back to work.

Making repairs
Making repairs
Posted on

Jeff Grevert, June 9, 2005

NOAA Teacher at Sea
Jeff Grevert
Onboard NOAA Ship Delaware II
June 8 – 16, 2005

Mission: Surf Clam Survey
Geographical Area: New England
Date: June 9, 2005

Catch of the day
Catch of the day

Weather Data
Latitude: 38 39 N
Longitude: 73 50 W
Visibility: < 0.5 nm
Wind Direction: 190
Wind Speed: 10 kts
Sea Wave Height: 2′
Swell Wave Height: N/A
Sea Water Temp: 15.8 C
Sea Level Pressure: 1021.4 mb
Cloud Cover: Fog

0530 – I was awoken by a NOAA scientist.  He informed my cabin mates and me that the 6-12 watch had to wake up, and the 12-6 watch only had to wake up if they wanted breakfast. I got up to get a bite to eat.

1000 – Woke up and started preparing for the day. Ate lunch.

1200 – Went on watch.

Sample sorting
Sample sorting

1500 – Arrived to our first sampling site.  Donned foul weather gear. We are now sampling in the Atlantic Ocean approximately 30 – 40 miles off Delaware Bay.  Our first trawl yielded Ocean Quahogs (Arctica islandica) and Sea Scallops (Placopecten magellanicus).  Some bycatch included a few skates, a crab and some razor clams (Ensis directus). In a later trawl, I volunteered to go up into the trap to clear out any amount of the catch that was stuck in the apparatus.  I received instruction from the chief scientist on checking for bent valves in the water pump apparatus.  When the trap is lowered to the sea floor, a high-pressure water pump shoots water into the benthic zone directing shellfish into the trap.  The valves must be checked after every trawl to ensure that they are straight and clear. Bent valves must be replaced. I checked the valves for the remaining trawls in my watch and had to replace one.  After assisting with sorting the catches, I began to collect data on the Ocean Quahogs. Shell length, total mass and meat mass were collected.

1800 – Off watch. Ate dinner. Elected to stay awake to complete log entry and gather meteorological data from the ship’s weather log.  Preparing to back on watch from 0000 June 09 – 0600 June 10.

Activities on deck
Activities on deck
Posted on

Jeff Grevert, June 8, 2005

NOAA Teacher at Sea
Jeff Grevert
Onboard NOAA Ship Delaware II
June 8 – 16, 2005

Mission: Surf Clam Survey
Geographical Area: New England
Date: June 8, 2005

Jeff Grevert, ready to set sail
Jeff Grevert, ready to set sail

Weather Data
Latitude: 41° 22′ N
Longitude: 070° 53′ W
Visibility: 5 nm
Wind Direction: 220°
Wind Speed: 11 kts
Sea Wave Height: 1′
Swell Wave Height: 2′
Sea Water Temp:  14.3° C
Sea Level Pressure: 1041.8 mb
Cloud Cover: 1/8; Altocumulus, Cirrus

Science and Technology Log

0900 – DELAWARE II changed docks; I assisted with lashing the cargo net beneath the gangway.

1200 – Participated in an interview conducted by an intern at the National Marine Fisheries Service Ecosystems Surveys Branch. The objective is to create an interactive DVD to promote NOAA programs.

1300 – Embarked from Woods Hole Mass.

grevert_log1a1400 – All hands aboard the DELAWARE II participated in ship drills for fire and abandoning ship. All hands onboard had to report with a life jacket, a survival immersion suit, a hat, long pants and a long sleeve shirt. My station was the stern at life raft # 2.  On the stern, we all learned how to don our survival immersion suits.

1500 – The scientific crew and I participated in a practice bottom trawl to learn how to conduct clam surveys. The clam survey is the primary scientific objective of this cruise.  I was briefed on deck safety, chain of command and research protocol. After the trawl (~5 minutes), the scientific crew on watch and I sorted the catch.  The organism collected in the greatest abundance was the Surf Clam (Spisula soldissima).  Other organisms collected included sea stars of the genus Asterias.  The Surf Clams were sorted into three categories: live, clappers (a specimen where the bivalve shell and hinge are intact but with no meat) and dead (a bare half shell).  One of the scientists from the national marine fisheries service gave me training on entering data into the Fisheries Science Computer System.  This is a software application designed specifically for fisheries research.  Parameters recorded included: shell length, overall mass and meat mass.

1900 – The first officer of the DELAWARE II gave me instruction on understanding nautical codes from the ships log for recording cloud cover, cloud type and other meteorological conditions.  A nautical day starts at 1200 noon. Since we were still in port at that time, I recorded the first entry into the ship’s weather log.