Julia Harvey: We Came, We Fished, Now What? August 8, 2013

NOAA Teacher at Sea
Julia Harvey
Aboard NOAA Ship Oscar Dyson (NOAA Ship Tracker)
July 22 – August 10, 2013  

Mission:  Walleye Pollock Survey
Geographical Area of Cruise:  Gulf of Alaska
Date:  8/8/13 

Weather Data from the Bridge (as of 17:00 Alaska Time):
Wind Speed:  15.72 knots
Temperature:  13.4 C
Humidity:  73%
Barometric Pressure:  1012.1 mb

I just read this heads up about the weather tonight.
I just read this heads up about the weather tonight.

 

Science and Technology Log:

We came.  We fished.  We measured, counted and weighed.  Now What?  We completed one last trawl on Tuesday night (August 6th).  When we finished we had caught over 65,000 walleye pollock and a whole lot of POP (Pacific ocean perch) on this leg of the survey.

The scientists now process and analyze the data.

Darin Jones and Chief Scientist Patrick Ressler going over data collected.
Darin Jones and Chief Scientist Patrick Ressler going over data collected.

Darin and Patrick will present at a public meeting when we are back in Kodiak on Friday.  They will discuss what was seen and preliminary findings of the walleye pollock survey.  Back in Seattle the MACE team will further evaluate the data along with data from the bottom trawl survey and determine the walleye pollock biomass for the Gulf of Alaska.  This will then be taken under advisement by the North Pacific Fishery Management Council.

There is also the lab to clean.  Even though we cleaned the lab after each trawl, it needed a good scrub down.  There were scales and slime hidden everywhere.  Just when you thought you were done, more scales were discovered.

Kirsten, Abigale and Darin cleaning the fish lab.
Kirsten, Abigale and Darin cleaning the fish lab.

Did You Know?

The note on the white board stated that there will be beam seas tonight.  What does that really mean?  It means the waves are moving in a direction roughly 90° from our heading.  So the water will be hitting us at a right angle to our keel.  It will be a rocking boat tonight.

Darin took a sample of the salmon shark’s fin when we caught it.  It will be sent to a scientist in Juneau who works at Auke Bay Laboratories (where Jodi works).  The sample will be used to examine the population genetics of the salmon shark and other species such as the Pacific sleeper shark.

Personal Log:

In my first blog, I wrote about a childhood dream of becoming an oceanographer.  After my third year of teaching in the Peace Corps, I decided education was my new direction.   I was excited to taste that bygone dream aboard the Oscar Dyson.  How do I feel now?  I jokingly sent an email to my assistant principal telling her to look for a new science teacher because I love life at sea.  I  love collecting data in the field.  Although I was not responsible for analyzing the data and I do miss my boys, I had an awesome cruise.  So where does that leave me?

Heading to Kodiak across the Gulf of Alaska
Heading to Kodiak across the Gulf of Alaska

It leaves me back in the classroom with an amazing sea voyage experience to share with my students.  I will always long for that oceanographic career that could have been.  But perhaps after my experience, I will inspire future oceanographers and fisheries scientists.  And I would do Teacher at Sea again in a heartbeat.  I will follow up with the outcomes and biomass estimates from MACE (Mid-Water Assessment & Conservation Engineering) and I will most definitely follow Jodi’s research on the use of multibeam sonar for seafloor mapping.

I want to say thank you to everyone who made my experience one of the best of my life and definitely the best professional development of my career.  Thank you to Jennifer Hammond, Elizabeth McMahon, Jennifer Annetta, Emily Susko and Robert Ostheimer for the opportunity to participate in the NOAA Teacher at Sea Program.  Thank you to NOAA for developing a practical and realistic opportunity to connect my students to ocean science.  Thank you to the science team (Chief Scientist Patrick Ressler, Darin Jones, Paul Walline, Jodi Pirtle, Kirsten Simonsen, and Abigale McCarthy) aboard the Oscar Dyson for their willingness to train me, answer all of my questions, preview my blogs, and to allow me have a glimpse of their lives as scientists.  Thank you to Patrick Ressler and XO Chris Skapin for promptly providing feedback on my blogs.  And a special thanks to the night shift crew (Jodi, Paul and Darin).  I was very nervous about adjusting to my work hours (4 pm to 4 am) especially after falling asleep that first night, but I am very grateful for colleagues who were fascinating and night-time enjoyable.  Chats with everyone aboard the Oscar Dyson from fishermen to NOAA Corps to engineers to stewards to scientists were educational and pleasant.  I met lots of people from all over the U.S. and some just from Newport (2 hours from Eugene).

WOW.  How fortunate was I to be chosen?  I am nearly speechless about what I saw and what I did.  What a mind blowing three weeks.  Thank You!  Thank You!  Thank You!

Now I begin the transition of living during daylight hours.

Here I am
Here I am before the system hit us.

I hope everyone was able to sample a little of my adventure.  I appreciate everyone who followed my blog especially Camas Country Mill folks.

Julia Harvey: Calibration in Sea-Otterless Sea Otter Bay, August 7, 2013

NOAA Teacher at Sea
Julia Harvey
Aboard NOAA Ship Oscar Dyson (NOAA Ship Tracker)
July 22 – August 10, 2013 

Mission:  Walleye Pollock Survey
Geographical Area of Cruise:  Gulf of Alaska
Date: 8/7/13 

Weather Data from the Bridge (as of 21:00 Alaska Time):
Wind Speed:  10.42 knots
Temperature:  13.6 C
Humidity:  83%
Barometric Pressure:  1012.4 mb

Current Weather: A high pressure system is building in the east and the swells will increase to 8 ft tonight.

Science and Technology Log:

Before I begin, I must thank Paul for educating me on the calibration process.  Because calibration occurred during the day shift, I was not awake for some of it.

The EK60 is a critical instrument for the pollock survey.  The calculations from the acoustic backscatter are what determines when and where the scientists will fish.  Also these measurements of backscatter are what are used, along with the estimates of size and species composition from the trawling, to estimate fish biomass in this survey.  If the instruments are not calibrated then the data collected would possibly be unreliable.

Calibration of the transducers is done twice during the summer survey.  It was done before leg one in June, which began out of Dutch Harbor, and again now near Yakutat as we end leg three and wrap up the 2013 survey.

As we entered Monti Bay last night, Paul observed lots of fish in the echosounder.  This could pose a problem during calibrations.  The backscatter from the fish would interfere with the returns from the spheres.  Fortunately fish tend to migrate lower in the water column during the day when calibrations were scheduled.

This morning the Oscar Dyson moved from Monti Bay, where we stopped last night, into Sea Otter Bay and anchored up.  The boat needs to be as still as possible for the calibrations to be successful.

Monti and Sea Otter Bays Map by GoogleEarth
Monti and Sea Otter Bays
Map by GoogleEarth
Site of calibration: Sea Otter Bay
Site of calibration: Sea Otter Bay

Calibration involves using small metal spheres made either of copper or tungsten carbide.

Chief Scientist Patrick Ressler with a tungsten carbide sphere
Chief Scientist Patrick Ressler with a tungsten carbide sphere
Copper sphere photo courtesy Richard Chewning (TAS)
Copper sphere
photo courtesy Richard Chewning (TAS)

The spheres are placed in the water under transducers.  The sphere is attached to the boat in three places so that the sphere can be adjusted for depth and location.  The sphere is moved throughout the beam area and pings are reflected.  This backscatter (return) is recorded.  The scientists know what the strength of the echo should be for this known metal.  If there is a significant difference, then data will need to be processed for this difference.

The 38 khz transducer is the important one for identifying pollock.  A tungsten carbide sphere was used for its calibration. Below shows the backscatter during calibration, an excellent backscatter plot.

Backscatter from calibration
Backscatter from calibration

The return for this sphere was expected to be -42.2 decibels at the temperature, salinity and depth of the calibration  The actual return was -42.6 decibels.  This was good news for the scientists.  This difference was deemed to be insignificant.

Personal Log:

Calibration took all of the day and we finally departed at 4:30 pm.  The views were breathtaking.  My camera doesn’t do it justice.  Paul and Darin got some truly magnificent shots.

Goodbye Yakutat Bay
Goodbye Yakutat Bay

As we left Yakutat Bay, I finally saw a handful of sea otters.  They were never close enough for a good shot.  They would also dive when we would get close.  As we were leaving, we were able to approach Hubbard Glacier, another breathtaking sight.  Despite the chill in the air, we stayed on top getting picture after picture.  I think hundreds of photos were snapped this evening.

The Oscar Dyson near Hubbard Glacier
The Oscar Dyson near Hubbard Glacier
Location of Hubbard Glacier.  Map from brentonwhite.com
Location of Hubbard Glacier. Map from brentonwhite.com
Many came out in the cool air to check out Hubbard Glacier
Many came out in the cool air to check out Hubbard Glacier
I even saw ice bergs floating by
I even saw ice bergs floating by
Lots of ice from the glacier as we neared
Lots of ice from the glacier as we neared
Nearby Hubbard Glacier with no snow or ice
Near Hubbard Glacier
And there it is: Hubbard Glacier
And there it is: Hubbard Glacier
Hubbard Glacier
Hubbard Glacier
Hubbard Glacier
Hubbard Glacier

Did You Know?

According to the National Park Service, Hubbard Glacier is the largest tidewater glacier in North America.  At the terminal face it is 600 feet tall.  This terminal face that we saw was about 450 years old.  Amazing!

Read More about Hubbard Glacier

Julia Harvey: Working on the Night Shift (During Shark Week), August 5, 2013

NOAA Teacher at Sea
Julia Harvey
Aboard NOAA Ship Oscar Dyson (NOAA Ship Tracker)
July 22 – August 10, 2013     

Mission:  Walleye Pollock Survey
Geographical Area of Cruise:  Gulf of Alaska
Date:  8/5/13 

Weather Data from the Bridge (as of 17:00 Alaska Time):
Wind Speed:  9.54 knots
Temperature:  15.7 C
Humidity: 83 %
Barometric Pressure:  1017.9 mb

Current Weather: The winds have decreased and we are not moving as much.  The weather report calls for an increase to the winds with 7 ft swells on Wednesday.  But maybe it will die down before it reaches us.

August 6th sunset
August 6th sunset

Science and Technology Log:

We only will fish during daylight hours.  The sun is now setting before 10:00 pm and rising around 5:30 am.  And even though we are not fishing between sunset and sunrise, science continues.  At nightfall, we break transect and Jodi begins her data collection.

The Sustainable Fisheries Act mandates an assessment of essential fish habitat.  This is in conjunction with stock assessments of groundfish.   Jodi’s research involves integrating multibeam accoustic technology to characterize trawlable and untrawlable seafloor types and habitat for managed species.

Species that are part of the groundfish survey.
Species that are part of the groundfish survey.
Photo courtesy of Chris Rooper (Alaska Fisheries Science Center) from the Snakehead Bank multi-beam survey

A bottom trawl survey is conducted every other year in the Gulf of Alaska.  The goal is to better identify seafloor types using multibeam acoustics.  This would help improve groundfish assessment, and limit damage to habitat and trawling gear.

The Gulf of Alaska survey area is divided into square grids.

Trawlable or Untrawlable?
Trawlable or Untrawlable?

On this cruise we are conducting multibeam mapping in trawlable and untrawlable grid cells.  A grid cell is divided into 3 equidistant transects for a multibeam survey.  Jodi directs the ship to follow these smaller transect lines.  While the ship is following the transects lines, the multibeam sonar is active and data is collected.

Multibeam sonar
Multibeam sonar
Photo courtesy of Tom Weber (University of New Hampshire)
Jodi monitors the screen during ME70 activity.
Jodi monitors the screen during ME70 activity.

The SIMRAD ME70 is the multibeam sonar that Jodi is using for her research.  There are 6 transducers on the ship that will send out a fan of 31beams of varying frequencies.  The strength of their return (backscatter) can be analyzed for sea floor type.  Looking at the diagram below, you can see the differences in backscatter clearly in the range of 30 to 50 degrees (away from straight down).

Illustration of the multi-beams generated. photo courtesy of http://www.id-scope.mc/Geophy03_EN.html
Illustration of the multi-beams generated.
photo courtesy of http://www.id-scope.mc/Geophy03_EN.html

Silts will have a very weak backscatter and rock will have a strong backscatter.

Substrate differences when looking at 30 - 50 degrees. Courtesy of Jodi Pirtle
Substrate differences when looking at 30 – 50 degrees.
Courtesy of Jodi Pirtle

After the transects are completed,  Jodi and Darin complete 1 – 3 camera drops to record visually how the seafloor appears.  This camera below will be lowered to the ocean floor and video footage will stream to the computer for 10 minutes.  Then the camera is brought up.

Drop Camera
Drop Camera

An example of an untrawlable area. Photo courtesy of Jodi Pirtle
An example of an untrawlable area.
Photo courtesy of Jodi Pirtle.

Last night, Darin gave me the opportunity to operate the camera drop.  After a bit of instruction, it was showtime.  I am very grateful for the chance to explore the seafloor.

I operated the drop camera.   Photo by Darin Jones
I operated the drop camera.
Photo by Darin Jones

Here is what I saw at 190 meters.

Fish and rocks on the seafloor.
Fish and rocks on the seafloor.
I saw a flatfish right in front of the camera.
I saw a flatfish right in front of the camera.

For more photos of my drop camera experience, see the end of this blog.

CTD (conductivity, temperature, depth) drops are conducted in the grid as well.  Data that are gathered are used to correct for the speed of sound under varying conditions of the ocean.

CTD drop to record physical oceanographic data
CTD drop to record physical oceanographic data

The next day, Jodi processes the data from the ME70.  The bottom detection algorithm (a series of calculations) removes backscatter from the water column (from fish).

Each frame product represents 5 minutes of seafloor.  The following are outcomes from the algorithm and represent angle dependent data.  The images below, show backscatter on the left and bathymetry on the right.

This represents a homogenous sea floor.
This represents a homogenous sea floor.
This represents a heterogenous sea floor.
This represents a heterogenous sea floor.

Then Jodi takes into account a number of factors such as results from the CTD, motion of the boat (offset, attitude, pitch, roll), and tides.  These uncertainties are applied.

Uncertainties Photo courtesy of NOAA
Uncertainties
Photo courtesy of NOAA

Then she mosaics the data.

Result from Jodi's data.
Results
Photo courtesy of Tom Weber

The color image above represents the depth and the bottom image provides information on seafloor substrate.

The footage from the camera drops is also reviewed for more evidence of the seafloor substrate and to look for objects that would snag trawl nets.

I really appreciate Jodi taking the time to educate me on her research.  Her passion for her work is evident.  I look forward to seeing where her research leads.

Personal Log:

So who actually works the night shift (4pm to 4 am) in the “cave”.   Jodi Pirtle, Paul Walline and Darin Jones are the three scientists I have been lucky to work with during my cruise.

I  discussed Jodi’s work on the ship in the science section.  She has an extensive educational background.  She earned a BS in Biology from Western Washington University in Bellingham and then a MS in Environmental Science from Washington State University in Vancouver.  Then she earned a Ph.D in Fisheries from the University of Alaska at Fairbanks.  Her thesis was on ground fish habitat on rocky banks along the US west coast.  And her dissertation was based on red king crab nursery habitat.  She just finished her postdoc at the University of New Hampshire Center for Coastal and Ocean Mapping where her work applied multibeam acoustics to study trawlable and untrawlable seafloor types and groundfish habitat in the Gulf of Alaska.  She is now working on groundfish habitat suitability modeling after she was selected to be a National Research Council NOAA postdoc at the Alaska Fisheries Science Center Auke Bay Lab in Juneau.  Jodi continues to integrate multibeam acoustics in her research at ABL.

Jodi was born and raised in Cordova, Alaska which we came near when we were in Prince William Sound.  I have enjoyed listening to her speak of growing up in Alaska.  There are no roads out of Cordova, so imagine traveling with a sports team in high school?  I will not forget how she described the Exxon Valdez oil spill to me from the eyes of herself at 11 years old.

I have greatly appreciated her knowledge of the creatures we bring up in the nets.  She has an eye for finding the hidden gems like the chaetognath (arrow worm).

Jodi with a lumpsucker fish
Jodi with a lumpsucker fish

Jodi enjoys cross country skiing, snow boarding, berry picking, hiking and yoga.  She introduced me to beautiful ripe salmon berries back on Kodiak.

Delicate Salmonberries
Delicate salmon berries

Darin is a MACE (Midwater Assessment & Conservation Engineering) scientist who earned his BS in Marine Biology from the University of North Carolina at Wilmington and then his MS in Fisheries Resources form the University of Idaho at Moscow.  His master’s work involved disease resistance in bull trout.  He spent 5 years collecting fishing data as an observer aboard commercial fishing boats in Alaska.  He also tagged cod on George’s Bank and worked at several conservation fish hatcheries before moving to Seattle to work for MACE.  Darin is part of the team to assess the biomass of the walleye pollock in the Gulf of Alaska.

Darin filets some of the fish caught.
Darin filets some of the fish caught.

I have heard that Darin played in a band with some MACE colleagues but they broke up because one of them moved.  Maybe there will be a reunion tour.

Darin measuring a spiny dogfish
Darin measuring a spiny dogfish

He is a surfer and has surfed on Kodiak but his favorite surf spot so far was in Costa Rica. Darin is an easy-going guy who I often call Scott because he reminds me so much of a colleague at school.  Darin has patiently explained my tasks to me and helped me learn what I am really doing.  And he supported me as I did my first camera drop.

Darin watching me control drop camera. Photo by Jodi Pirtle
Darin watching me control drop camera.
Photo by Jodi Pirtle

Paul is a native of Washington state and completed his academics there as well.  He earned a BS in Oceanography and a Ph.D in Fisheries Oceanography from the University of Washington.  For 20 years he worked at the Israel Limnological and Oceanographic Institute.  He was involved in managing the water quality in Lake Kinneret.  His role was to estimate the number of fish to determine their affect on water quality.  Paul accomplished this by developing acoustics surveys of fish stocks in Israel.  Lake Kinneret, also known as the Sea of Galilee, provides Israel with 40% of its drinking water.

Lake Kinneret Courtesy of GoogleEarth
Lake Kinneret
Courtesy of GoogleEarth

In 2000, Paul moved back to Seattle and is working as a fisheries biologist for MACE.

Paul reading echograms and deciding to fish
Paul reading echograms and deciding to fish

I have been fortunate to see photographs that Paul has taken both on this trip and elsewhere.  He has an incredible talent for finding beauty.

Paul Walline
Paul Walline

I am writing this as we are tossing and turning in ten foot swells.  According to Paul, it doesn’t matter if the swells get any  bigger because the effect is the same. His calmness, knowledge and expertise remind me a lot of my dad.

As you can see, I worked with amazing, brilliant individuals.  The night shift rules.  We had awesome teamwork when a haul needed to be processed.

Jodi weighs and measures the pollock.  Darin removes otoliths and I packaged them up
Jodi weighs and measures the pollock. Darin removes otoliths and I packaged them up

And then we slept through the fog and awoke to beautiful sunsets (on some days).

Sunset by Yakutat Bay
Sunset by Yakutat Bay

Did You Know?

Glacial runoff changes the color of the ocean.  Compare the two photos.  The one at the bottom is near a glacier.

 

The ocean with no glacial runoff.
The ocean with no glacial runoff.
The ocean with glacial runoff.
The ocean with glacial runoff.

Animals Seen Today:

The bottom trawl that was brought up right when I began work, contained three types of sharks.  The smaller ones were spiny dogfish and spotted spiny dogfish.  The big one was a salmon shark.  Check out the video.

To read more about salmon sharks and to monitor their migration pattern, check out the content on Tagging of Pacific Predators website.  Click here: TOPP

My Drop Camera Experience

Checking out the bottom with the drop camera. Photo by Jodi Pirtle
Checking out the bottom with the drop camera.
Photo by Jodi Pirtle
Jodi and I monitoring the drop cam. Photo by Darin Jones
Jodi and I monitoring the drop cam.
Photo by Darin Jones
Julia bringing drop camera aboard. Photo by Darin Jones
Julia bringing drop camera aboard.
Photo by Darin Jones
Sea urchin in color.
Sea urchin in color.
Fish hiding on the left.
Fish hiding on the left.
Another sea urchin
Another sea urchin