Tag: myctophid fish

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Jennifer Fry: March 16, 2012, Oscar Elton Sette

NOAA Teacher at Sea
Jennifer Fry
Onboard NOAA Ship, Oscar Elton Sette
March 12 – March 26, 2012

Mission: Fisheries Study
Geographical area of cruise: American Samoa
Date: March 16, 2012

Pago Pago, American Samoa

Science and Technology Log:

The day began on the Oscar Elton Sette with the small boat going  Pago Pago harbor to re-fuel and collect supplies.  That’s about the time I went to sleep. My own day started by waking up at 5:00 p.m. to rougher seas and unfortunately feeling a bit queasy.  I took a walk outside hoping to get a bit of fresh air and relief. A gently rain fell as I peered over the ship’s railings.  Thankfully the strong wind on my face helped my uneasiness.

Midwater Cobb Trawl 5.1

Animals Seen:

Squid

Trigger fish juvenile

Morey eel larvae

Pyrosome, various sizes

Puffer fish juvenile

Mola  (sunfish)  juvenile

Data collected Trawl 5.1

The data collected included:

Name of fish: Numbers Count Volume (milliliters) Mass (grams)
Myctophids 118 120 135
Non-Myctophids 81 46 60
Crustaceans 5 Negl Negl
Cephalopods:. . 14 32 60
Gelatinous zooplankton 51 114 85
Misc. zooplankton n/a 160 185

Data Collected  Trawl 5.2

The data collected included:

Name of fish: Numbers Count Volume (milliliters) Mass (grams)
Myctophids 168 200 254
Non-Myctophids 209 130 125
Crustaceans 14 6 17
Cephalopods: 14 200 230
Gelatinous zooplankton 58 38 35
Misc. zooplankton n/a 366 365

The first trawl began a 9:00 p.m. and the second at approx. 1:30 a.m.

Some very interesting specimens were in the net including:

  • A variety of  squid: the largest measuring approx. 12 inches with out the tentacles,
  • one  juvenile trigger fish
  • 350 mm viper fish
  • Pyrosomes of various sizes
  • One juvenile puffer fish
  • Several Morey eel juvenile
  • Two juvenile sun-fish, Mola

While retrieving the trawl nets a light, warm rain sprinkled on us.  We worked very hard, yet had an amazing amount of fun.  Researchers Emily Norton and Louise Giuseffi joined during the tow.  I think the saying goes, “The more scientists the merrier.” 

While we measured, weighed, collected data, and examined our catch,  songs emanated from the iPod  playing in the wet-lab.  As lengths and weights were recorded, voices sang along  to the tunes into the wee hours of the morning.  The theme  song for tonight was Green Day’s  “Hope you Had the Time of Your Life.”

I certainly am.

Everyone teacher needs to be a NOAA Teacher at Sea to experience first hand the amazing work scientists do each day.

It is now 11 :59 a.m. and time for sleep.

 So much excitement, so many fish, so little time.

Scientist, Aimee Hoover is ready to input data from the midwater Cobb trawl which includes temperature and depth.

Pictured are American Samoan scientist, Sione "Juice" Lam Yuen and a squid found in the Cobb trawl net. Sione is ready to weigh and measure the squid.

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Jennifer Fry: March 14, 2012, “Pi Day” 3.14, Oscar Elton Sette

NOAA Teacher at Sea
Jennifer Fry
Onboard NOAA Ship, Oscar Elton Sette
March 12 – March 26, 2012

Mission: Fisheries Study
Geographical area of cruise: American Samoa
Date: March 14, 2012

At Sea: Pago Pago, American Samoa

Science and Technology Log:

My current assignment aboard ship is helping the scientists with the “Nighttime Cobb Trawling”  We conduct two trawls in the night, the first one beginning around 9:00 p.m. and the second one at 1:30 a.m..  After each trawl which lasts 2 hours, the nets are brought up and we sort the catch.  The scientists are looking for migration patterns and types of sea life in this region.  Not much data has been collected  in American Samoa.

There are 3 other  scientists working on this project.

John Denton, is from the Natural History Museum in New York.

Aimee Hoover works for University of Hawaii.

Sione “Juice” Lam Yuen and Faleselau “House” or “Fale” Tuilagi are from the Fisheries Dept .in American Samoa.

The two trawls exaimine five species of fish:

  1. Myctophid fish
  2.  non-myctophid fish
  3.  crustaceans
  4.  gelatinous zooplankton
  5.  cephalopods

During one of the trawls the other night, they think they found a new species of myctophid fish. These fish have photophores which make them glow in the dark.  They are anywhere from 4-5 inches to very tiny, 1 inch.

Myctophids are among the most numerous fish in the sea. They have specific light producing organs called photophores.

After 4 days on the  night shift, I’m getting into the groove.  Going to sleep at 6 a.m. and waking up at 1:00 p.m.

It’s crazy.  Last night we did 2 trawls for fish.  We caught a huge fish, approx 4 feet in diameter, called a Sharptail mola, Masturus lanceolatus or Sunfish.  The scientists and crew were able to  free him and let him go back into the ocean. Click here to see the exciting video of the release of the Mola: Releasing the  Sharptail mola, Masturus lanceolatus/ Sun-fish

During tonight's Cobb trawl a sharp-tailed mola was caught in the net. The crew and scientists aided in freeing the fish allowing him to swim away. Mola can reach 100 years old.

When conducting a scientific experiment it is very important to maintain the same procedure or protocol.  This allows the scientist to measure only that which he/she is interested in, keeping all constants the same.

Here is the procedure or protocol for each Midwater Cobb Trawl:

1. Secure the TDR and Netminds tracking devices to  the trawl net Let out the trawl net, timing for 30 minutes at 350 meters of “wire out.”

2.  Ask the bridge and trawl net operator to raise the net line to 100 meters “wire out.”

3.  Time the trawling for additional 30 minutes.

4.  Once the trawl net has been hauled in:

5. Cut away the TDR and Netminds tracking devices: Their data is read on the computer.   Helping scientists determine temperature, depth   for each trawl.

6. Working together, scientist and crew members collect the specimens caught is the Cobb net.

7. The fish collected are taken to the wet lab and strained into a net that is in turn poured into examining trays.

8. Scientists then collect data including: weight (volume & mass), length (centimeters) ,  and count the number of each species recording the

minimum and maximum lengths.

9.   The scientists preserve each group of fish in ethanol/ ethyl alcohol  which eases transportation and preserves the fish for further study back in the lab.

Personal Log:

I’ve switched to working the night shift, tonight being the third night.  It’s getting a little easier, although we all still get punchy around 3-4 a.m.  I am scheduled to work nights until next Monday.  We will continue counting the fish, setting the trawl nets out, imputing the data, preserving the fish.  All very interesting work.

Animals Seen:

Sharptail mola, Masturus lanceolatus fish

Moorish Idol fish

Two Moorish Idol fish were caught in the Cobb Trawl net. Their colors were brilliant including their unique dorsal filament.
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Becky Moylan: Preliminary Results, July 13, 2011

NOAA Teacher at Sea
Becky Moylan
Onboard NOAA Ship Oscar Elton Sette
July 1 — 14, 2011


Mission: IEA (Integrated Ecosystem Assessment)
Geographical Area: Kona Region of Hawaii
Captain: Kurt Dreflak
Science Director: Samuel G. Pooley, Ph.D.
Chief Scientist: Evan A. Howell
Date: July 13, 2011

Ship Data

Latitude 1940.29N
Longitude 15602.84W
Speed 5 knots
Course 228.2
Wind Speed 9.5 knots
Wind Dir. 180.30
Surf. Water Temp. 25.5C
Surf. Water Sal. 34.85
Air Temperature 24.8 C
Relative Humidity 76.00 %
Barometric Pres. 1013.73 mb
Water Depth 791.50 Meters

Science and Technology Log

Results of Research

Myctophid fish and non-Myctophid fish, Crustaceans, and gelatinous (jelly-like) zooplankton
Crustaceans
Chief Scientist guiding the CTD into the ocean
Chief Scientist guiding the CTD into the ocean

Beginning on July 1st, the NOAA Integrated Ecosystem Assessment project (IEA) in the Kona region has performed scientific Oceanography operations at eight stations.  These stations form two transects (areas) with one being offshore and one being close to shore. As of July 5th, there have been 9 CTD (temperature, depth and salinity) readings, 7 mid-water trawls (fish catches), over 15 acoustics (sound waves) recordings, and 30 hours of marine mammal (dolphins and whales) observations.

The University of Hawaii Ocean Sea Glider has been recording its data also.The acoustics data matches the trawl data to tell us there was more mass (fish) in the close to shore area than the offshore area. And more mass in the northern area than the south. This is evidence that the acoustics system is accurate because what it showed on the computer matched what was actually caught in the net. The fish were separated by hand into categories: Myctophid fish and non-Myctophid fish, Crustaceans, and gelatinous (jelly-like) zooplankton.

Variety of Non-Myctophid Fish caught in the trawl
Variety of Non-Myctophid Fish caught in the trawl

The CTD data also shows that there are changes as you go north and closer to shore. One of the CTD water sample tests being done tells us the amount of phytoplankton (plant) in different areas. Phytoplankton creates energy by making chlorophyll and this chlorophyll is the base of the food chain. It is measured by looking at its fluorescence level. Myctophids eat phytoplankton, therefore, counting the amount of myctophids helps create a picture of how the ecosystem is working.

The data showed us more Chlorophyll levels in the closer to shore northern areas . Phytoplankton creates energy using photosynthesis (Photo = light, synthesis  = put together) and is the base of the food chain. Chlorophyll-a is an important pigment in photosynthesis and is common to all phytoplankton. If we can measure the amount of chlorophyll-a in the water we can understand how much phytoplankton is there. We measure chlorophyll-a by using fluorescence, which sends out light of one “color” to phytoplankton, which then send back light of a different color to our fluorometer (sensor used to measure fluorescence). Myctophids eat zooplankton, which in turn eat phytoplankton. Therefore, counting the amount of myctophids helps create a picture of how the ecosystem is working.   The data showed us more chlorophyll-a levels in the closer to shore northern areas.

Bringing in the catch

The Sea Glider SG513 has transmitted data for 27 dives so far, and will continue to take samples until October when it will be picked up and returned to UH.

Overall the mammal observations spotted 3 Striped dolphins, 1 Bottlenose dolphin, and 3 Pigmy killer whales.  Two biopsy “skin” samples were collected from the Bottlenose dolphins. A main part of their research, however, is done with photos. They have so far collected over 900 pictures.

Looking at all the results so far, we see that there is an area close to shore in the northern region of Kona that has a higher concentration of marine life.  The question now is why?

We are now heading south to evaluate another region so that we can get a picture of the whole Eastern coastline.

Personal Log

In the driver's seat
In the driver's seat
Krill
Krill

And on deck the next morning we found all kinds of krill, a type of crustacean. Krill are an important part of the food chain that feed directly on phytoplankton. Larger marine animals feed on krill including whales. It was a fun process finding new types of fish and trying to identify them.Last night I found a beautiful orange and white trumpet fish. We also saw many transparent (see-through) fish with some having bright silver and gold sections. There were transparent crabs, all sizes of squid, and small clear eels. One fish I saw looked like it had a zipper along the bottom of it, so I called it a “zipperfish”. A live Pigmy shark was in the net, so they put it in a bucket of water for everyone to see. These types don’t ever get very big, less than a foot long.

I have really enjoyed living on this ship, and it will be sad to leave. Everyone treated me like I was part of the group. I have learned so much about NOAA and the ecosystem of the Kona coastline which will make my lessons more interesting this year. Maybe the students won’t be bored!

Sunrise over Kona Region

Sunrise
Sunrise