August 2010 – Page 2 – NOAA Teacher at Sea Blog

August 28, 2010April 22, 2021

Natalie Macke, August 28, 2010

NOAA Teacher at Sea: Natalie Macke
NOAA Ship: Oscar Dyson

Mission: BASIS Survey
Geographical area of cruise: Bering Sea

Date: 8/28/2010

It’s Fish Feeding Time…

Weather Data from the Bridge :

Visibility : <0.5 nautical miles (Wondering what a nautical mile is??)

Wind Direction: From the W at 20 knots

Sea wave height: 2-3ft

Swell waves: WSW, 4ft

Sea temp:9.1 oC

Sea level pressure: 1013.0 mb

Air temp: 9.7 oC

Science and Technology Log:

DSCN0314 — Euphausiid Specimens (zooplankton)

We’re up to station #40 now and everyone certainly has their routine down. One type of sampling I have yet to cover is the microscopic life; the base of the food web. A look at the marine fisheries food web quickly reveals that in order to support the commercial fisheries as well as the vast number of marine mammals and ocean birds, there must be an abundance of phytoplankton and zooplankton available in the Bering Sea. Evidence of this food chain is demonstrated by dissecting the stomach of a salmon. The sample (in the picture below) revealed that the salmon had recently dined on euphaussids (commonly known as krill). Before getting into how the zooplankton samples are collected, first let me go back and touch on the base of the food web; phytoplankton. These samples are collected from the Niskin bottles on the CTD each cast. The samples are preserved with formalin and will be brought back to the lab for further analysis. Now, back to the critters..

At every sampling station on the side deck and immediately after each CTD cast, zooplankton net tows are completed. There are three different tows being used for the BASIS survey. The first two are vertical tows where nets that are weighted are dropped to the seafloor and then brought back to the surface thus sampling a vertical water column. The pairovet, named from the fact that is was designed as a “pair of vertical egg tows” (designed to collect pelagic egg samples) has a netting mesh size of 150 microns. The net is simply deployed with a weight on the bottom. When it reaches the deepest part of the water column it is brought back to the surface collecting its’ sample. Another similar net with a 168 micron mesh size is named the Juday. Once either of these nets is brought to the deck, it is washed down and anything caught is captured in the cod end (the name for the PVC bucket at the bottom of the net).

Page_1_2 — Deploying the Bongo nets off the starboard side

The last type of tow that is completed for the BASIS survey uses the Bongo nets. This tow is considered an oblique tow since the nets essentially are lowered to about 5m from the ocean bottom and towed for a certain length of time. If you remember from the acoustics, in daylight hours the zooplankton migrate to the ocean bottom to hide from their prey. Since our sampling is done in daylight hours, the deep sampling depth is where we expect to find the highest density of zooplankton sample. The mesh sizes on the two nets of the Bongo are 335 and 505 microns. This allows for sampling of zooplankton of different sizes. The samples are collected on board and then taken back to the lab for analysis. They are separated by species, counted and weighed. Biomass and species composition is determined for each sample. The majority of the zooplankton we have seen this cruise have been euphaussids and copepods of varying types.

Oh where, oh where does the Internet go??

So as August winds down and the school year gears up, my connection to the Internet is becoming more and more important. Since my Oceanography class is with the Virtual High School, I have to essentially set up my virtual classroom in these upcoming days. I’ll assume my esteemed colleagues will assist me in unpacking lab equipment back at home at my physical classroom. (Even though I know.. all my orders will mysteriously wind up in other labs, I’m assured they’ll be safely placed away.)

So I tracked down Vince Welton, our Electronic’s Technician for some help understanding why sometimes I can surf, and why sometimes I can’t….

Simple…

Our Internet connection is via the geostationary satellite GE 23 at 172 degrees East. This satellite transmits over most of the Pacific Ocean (see a coverage map). Since this satellite is positioned on the equator, that means our receiver must look essentially due south for a signal. When our ship is northbound, the mast and stack of the Oscar Dyson simply gets in the way. Therefore… no Internet on northbound travels.

The Oscar Dyson also has access to two Iridium satellites for communication as well as the GE 23. These are the SAT-B which can transmit both data and voice communications and the VSAT which only allows voice transmission. The ship can access this set of orbiting satellites when the GE 23 is unavailable due to course of travel or weather conditions.

Personal Log

Yesterday, I got permission to stay on the trawl deck during one of our station trawls. It was fun to be outside down with the net. Jeanette helped do some taping which I hope to(during a few Internet-less days ahead) compile to a video for my classes. Of course as fate would have it, our catch for the day (shown below) was not one for the record books or even worth remembering at all.. I guess that’s what the editing process is for hmmm…

In the Oceanography lab, we have started our primary productivity experiments and chlorophyll analysis so learning these new procedures has been interesting and given me lots of ideas for some research topics for Edelberg’s class. All in all, I am enjoying watching, learning and doing science here in eastern Bering Sea. One week left..

August 28, 2010April 22, 2021

Beth Spear, August 28, 2010

NOAA Teacher at Sea: Beth Spear
Aboard NOAA Ship Delaware II

Mission: Shark and Red Snapper Survey
Geographical area of cruise: Gulf of Mexico
Date of Post: August 28, 2010

Attached are photos showing three different shark species including: sandbar, hammerhead, bull. Hammerheads are easily recognized by their distinctive heads and bull sharks have a solid grey skin, but very wide thick bodies. I am pictured below with an Atlantic sharpnose shark which grow to much smaller sizes as adults compared to the sharks species listed above.

Some sharks we caught were too large to be brought on board, so they were tagged from the ship’s deck. Tags need to be inserted almost anywhere on the dorsal surface of the shark except the fin or the gills. For each shark see if you can determine the shark type and gender. Click on the link below to access the video clips. Scroll down for the correct answer when you finish.

Video #2

Video #3

Answer: Shark / GenderShark #1
Hammerhead, maleShark #2
Bull, ?Shark #3

Sandbar, female

August 27, 2010April 22, 2021

Annmarie Babicki, August 27, 2010

NOAA Teacher at Sea: Annmarie Babicki
NOAA Ship Name: Oregon II
Mission: Bottom Longline Survey 2010
Geographical area of cruise: Gulf of Mexico
Date: August 27, 2010

Before I left for this cruise, I believed this would be a once in a lifetime experience. This trip exceeded all of my expectations and was due to everyone on board the Oregon II. I am forever grateful for all that I learned from all of you. I left the Gulf not just with knowledge about species of sharks, but also about what and how scientists collect data. There’s a great deal of responsibility in knowing that the data you collect, will be used to determine policy, which will impact the lives of so many people who live in the Gulf.

Your admiration, respect and compassion for sharks was evident in so many ways. You introduced me to some of the most beautiful and powerful creatures on this earth and I thank you for that. I am so very grateful to Trey for being open to having me as part of his team. He listened to and answered my many questions and was indeed very patient with me. I will bring back to my young students not only what I have been taught, but also the passion, I too, now feel for these animals. My hope is that it will inspire some of them to think about becoming scientists.

To NOAA’s Captain Dave and his very capable and wonderful crew, I would like you to know how much I appreciate you sharing your lives and expertise with me. I know that for much of the year, the Oregon II is your home and I am grateful that you were willing to share it with me. You are all so knowledgeable in what you do and I felt very safe on board your ship. The teamwork that I witnessed was impressive and you made running and driving the ship seem so easy. I will certainly convey to my students the role that your teamwork played in making our trip a successful and productive one. One of my goals upon returning to school will be to share your stories and the work you do. I want my students to know about the many career opportunities that are available to them if they have a love for the ocean. It could be that your story will be their inspiration.

I am very grateful to all of you for this incredible journey. I feel blessed to have so many memories that will last a lifetime. Safe Travel.

August 25, 2010April 22, 2021

Caroline Singler, August 25, 2010

NOAA Teacher at Sea: Caroline Singler
Ship: USCGC Healy

Mission: Extended Continental Shelf Survey
Geographical area of cruise: Arctic Ocean
Date of Post: 27 August 2010

Farthest North – 26 August 2010

Location and Weather Data from the Bridge

Date: 25 August 2010 Time of Day: 2300 (11:00 p.m. local time); 06:00 UTC
Latitude: 82º 29’ N Longitude: 138º 50.4’ W
Ship Speed: 4.5 knots Heading: 291º (NW)
Air Temperature: -0.5ºC / 31.1ºF
Barometric Pressure: 1010.7 mb Humidity: 97%
Winds: 9 knots SW
Sea Temperature: -1.2ºC Salinity: 28.2 PSU
Water Depth: 3400 mDate: 26 August 2010 Time of Day: 2230 (10:30 p.m. local time); 0530 UTC
Latitude: 82º 0.5’ N Longitude: 132º 5.5’ W
Ship Speed: 4.3 knots Heading: 163º (SE)
Air Temperature: -1.25ºC / 29.7ºF
Barometric Pressure: 1012.6 mb Humidity: 100%
Winds: 20.4 knots SW Wind Chill: -8.9ºC/15.9ºF
Sea Temperature: -1.35ºC Salinity: 28.47 PSU
Water Depth: 3643 m

We reached our farthest northern location in the early morning hours on Friday 26 August. We stopped a little before midnight local time on 8/25 (07:00 8/26 UTC) for a water sampling event and I captured this map that showed our location at latitude 80º31.85’.

Here is what the Arctic looks like at 82º31.5’N 139º15’W from the bow of the Healy.

I took the picture at the beginning of this post myself, at about the same time as the map shows!

We ended up a little farther north in the early morning as we maneuvered to get back in line withLouis, who rejoined us after some downtime for repairs.

Our official FARTHEST NORTH point was at latitude 82º32’. The original plan called for 85ºN, but the ice is thick and progress is slow, and we have had several delays. Now we are eastward bound, on a line that heads towards but ends before the Queen Elizabeth Islands of Canada. Healyspends a lot of time backing and ramming. There are numerous ridges in the ice formed when ice floes drift with the wind and currents and collide with other flows, and these present big obstacles. First they drive the ship into the ridge, then back up, leaving the impression of the ship’s bow like a snow angel.

There is an eerie silence when the ship is backing, and I expected it to be followed by a burst of speed (hence the backing and “ramming”), but the ship just drives forward again over the same track. It can take two or three times to break through a large ridge. Even then, it can be difficult for Louis to proceed with her towed gear even – often the pressure causes ice to drift back into the track before Louis can pass through. On numerous occasions Healy has had to double back to relieve the pressure on Louis by coming around and passing to the side of the ship, trying to give the ice a different way to drift. Sections of Healy’s track line look as if we are doing figure eights around Louis.

Since Sunday, we have been at latitudes where the sun does not set. I get off watch at midnight local time, but true midnight is usually an hour or two after that. Here are some views of the sky that I see when I leave the computer lab at night.

Midnight- 23 August 2010

Midnight- 24 August 2010

Midnight- 25 August 2010

Midnight- 27 August 2010

I can’t always see the sun, but it’s still pretty and peaceful, even when we are banging through ice.

Caroline

August 25, 2010April 22, 2021

Natalie Macke, August 25, 2010

NOAA Teacher at Sea: Natalie Macke
NOAA Ship: Oscar Dyson

Mission: BASIS Survey

Geographical area of cruise: Bering Sea

Date: 8/25/2010

The Sounds of Science…

Weather Data from the Bridge :

Visibility : 10+ nautical miles (Wondering what a nautical mile is??)

Wind Direction: From the ESE at 8 knots

Sea wave height: <1ft

Swell waves: NW, 1-2 ft

Sea temp:6.8 oC

Sea level pressure: 1018.1 mb

Air temp: 8.2 oC

Science and Technology Log:

DSCN0265 — Acoustician, Sandra Parker-Stetter on the Bridge preparing to fish..

When you walk into the acoustics lab you are greeted with an impressive display of primary colors and fascinating images. Sandy, our Acoustician is also there to greet you and help explain the science behind the images of sound. She explained not only the basics of acoustic science; but also shared some fascinating biological phenomena that can be witnessed with this technology.

So first some basics about the acoustics. (Hoping BTW to make Sandy proud about her skills in teaching a physics phobic.. She only made my head hurt a few times..) When you walk in the Acoustics Lab on the Oscar Dyson you will see there are six different acoustic displays in the lab:

18 kHz & 38 kHz on one display (These are more common to fishing vessels to distinguish larger fish from jellies, zooplankton and juvenile fish)
70 kHz, 120kHz, 200kHz and a 70 kHz with a sideway view from the ship.

The acoustic sounders positioned on the ship’s centerboard emit a ping that is transmitted directly downward from the boat (except one 70kHz pointed sideways).

These pings each have a set characteristic frequency designated by the unit of a kiloHertz (kHz). A kilohertz simply is the thousands of cycles per second that the wave is transmitted. Frequency is indirectly related to wavelength. So if you think about what will fit in-between the waves in the left image it will make sense that lower frequency acoustics are used to identify larger things, while higher frequency captures images of much smaller species or individuals.

Acoustics have the potential to not only identify schools of fish, but also discriminate between species types as well. A characteristic scattering is observed from different types of fish depending on their internal structure (morphology) and composition. For example, whether or not a fish has a swimbladder can be used for identification. A swimbladder will cause a greater acoustic scattering. In terms of composition, jellyfish are over 99% water. The more like the composition of water, the less the sound bounces off the specimen. Therefore, the scatter from the ping of the acoustics is weak and difficult to see on the monitor. However, the jellyfish signature is shows up quite strong on the acoustic monitors. In this case, the size and shape of the jellyfish causes the sound to scatter regardless of its’ composition. So acoustic analysis is not always as straight-forward as the scientists (and fishermen) would like. So how do the scientist tell a jellyfish from a juvenile salmon? Trawling data.. Part of the acoustic’s mission on our BASIS cruise. The scientists would like to develop patterns to match trawls with acoustic signals. Therefore, acoustics can be used in the future more effectively to track and monitor pelagic populations.

Biological Phenomena Visualized with Acoustic Technology

Zooplankton Migration
Using the 200kHz acoustics, tracking the movement of the zooplankton is quite easy. In the image to the left, taken and archived during the evening hours you can literally see how the zooplankton migrate toward the ocean surface as the sun sets(Around 10PM in these parts..). Trying to avoid their predators, the zooplankton stay near the ocean bottom during the daylight hours, but migrates upward toward their food source, the phytoplankton, once darkness begins to onset.

Riding the Pycnocline
Another interesting physical oceanographic feature you can observe with acoustics is the pycnocline. While you can’t literally see the density change of the water using the acoustics aboard this ship, you can watch the fish hover immediately above this feature.

Personal Log:

Yesterday morning’s sunrise was one for the books.. Tuesday was a glorious, sunny day aboard the Dyson.. (Uh.. the answer is YES.. apparently Alaskans do sunbathe in 50 degree weather. As long as the sun is out… I won’t mention any names.) The daytime turned to an evening with a sky full of stars. We then were treated to a spectacular sunrise the next morning with beautiful calm seas. Thanks to Sandy, who captured the picture to the left that morning, while most of us were busy eating omelets and pancakes in the Mess Hall.

It’s fun sometimes when Sandy’s right….

After days of searching for the juvenile salmon, we finally found their playground. One of trawls yesterday brought us over 2,000 sockeye juveniles along with a mess of jellies… After accosting my colleagues with a few paparazzi moments, it was fun to join in to help sort out the catch. And even sometimes when things don’t work out perfectly, finding what you’re looking for makes everything better. To the right is a snapshot of what happens when the bin doesn’t stop in time and the fish/jelly mess overtakes the belt and scientists. Now this is fishin’….