Journal

Research Update

The helicopter gods did not smile on us and we will not be heading to Cape Bird today. Luckily, there is still plenty to do. Today Terry Palmer, Carl Green and I will go take water monitoring samples in nearby dive holes. Andrew Klein and Steve Sweet are busy arranging sampling locations and labeling jars for when we start collecting sediment.

Steve Sweet labeling jars
Steve Sweet labels jars which will soon be filled with sediment to analyze.

Water Monitoring

Although our work is centered on sediment samples, Terry decided to use some free time to collect data on the water in McMurdo Sound. We walked back to the dive hut where we saw a seal yesterday so we could conduct the water tests. Although there weren't any seals inside, there was a warm space to collect some data!

Terry Palmer and Carl Green walking to dive hut
Terry Palmer carries a water quality instrument and walks with Carl Green out on the sea ice towards the dive hut.

Creating a Vertical Profile

Terry collected data in the water column under the dive hole using a CTDA research tool that is submerged in the water to measure conductivity (salinity), temperature, and depth., which is a water quality sensor that measures conductivity, temperature and depth. Conductivity measures how easily electricity flows through the water. This is related to the amount of salt in the water, along with the water's temperature. Terry's sensor also measures dissolved oxygen levels and pH levels, among other variables.

CDT in dive hole
Terry Palmer lowers a water quality instrument into the dive hole to measure temperature, salinity and other variables in the water.

Michelle Brown with CDT
Michelle Brown takes a turn using the CDT to test the water quality.

You can use this data to create a vertical profile--a graph that shows how a variable changes with height. Use the data from Terry's CTDA research tool that is submerged in the water to measure conductivity (salinity), temperature, and depth. to create graphs showing how salinity (amount of salt), temperature, oxygen levels and pH change in the sea ice from the surface down. Click here to access the worksheet: graphing_a_vertical_profile_in_mcmurdo_sound.docx

A Science-Lover's Dream

There are so many important science projects happening in McMurdo Station and everyone is happy to talk about their work. When we're all dining in the cafeteria, I often get to hear about science projects that are occurring in and around the station. That is how I heard about Amanda Kelley's work.

Studying Sea Urchins

Amanda is an ecological physiologist. Physiologists study how an organism or a part of an organism works. Ecological physiologists study how organisms function in the context of the environment. Amanda is looking at how sea urchins respond to ocean acidification and warmer ocean temperatures, which are consequences of climate change.

Looking through the Microscope

Today Amanda let me tag along as she checked in on her larval sea urchins. First we looked at her samples through a microscope.

Amanda Kelley looking through microscope
Amanda Kelley looks at sea urchin larvae through a microscope.

Sea urchin larva
A lone sea urchin larva shows off its newly-formed four feet. The circle in the center is its stomach, and tiny cilia line its body.

Amanda checks in on her samples to see what stage of development they are in. When we looked, they were about 14 days old and developing four feet. In colder latitudes, everything develops more slowly. Sea urchins in warmer latitudes can develop four feet by three days! Amanda wants to better understand what genes are being turned on and off at different stages of the urchins' development, especially when they are in warmer temperatures and water that is more acidic. When they are at different developmental stages she takes RNA samples of them which will allow her to see these differences.

Calculating Cellular Respiration, Understanding Stress

After checking in on the developmental stage of the sea urchins, Amanda tested the respiration of the larval sea urchins. When you hear "respiration" you may think of breathing. Breathing can play an important role in respiration (specifically aerobic respiration), but the focus is on releasing energy in the cell. The energy gets released through a series of chemical reactions--this is called cellular respiration. In aerobic respiration, which most animals and fungi use, oxygen is used to release that energy. Amanda measures the level of oxygen in the water surrounding the sea urchins to see how well they are respiring. This also helps her understand the sea urchins' metabolic rates. Factors like warmer temperatures or more acidity in the ocean may put stress on sea urchins and affect these levels. This is one of the things that Amanda is studying.

Sea urchin larvae in container
Tiny sea urchin larvae swim in a small vial of sea water. The levels of oxygen in the water are tested to measure respiration levels.

Amanda operates a very precise machine which uses light to calculate the amount of oxygen in the water. Before running the experiment, Amanda reviews a carefully written out procedure. She needs to be sure to replicate each trial exactly the same way so the results of her data are accurate.

Amanda Kelley studying procedures.
Amanda Kelley carefully reviews her procedures before using a machine to test oxygen levels in the sea water of sea urchins.

Once the procedure is reviewed, Amanda tests the levels of oxygen in the water surrounding different sea urchin larvae. The first round of tests were from larvae in water that was 2 degrees Celsius--a temperature that sea urchins might experience if the oceans warm. She then tested larvae that were in -1 degree Celsius water, which is closer to their natural habitat. I helped record data, including the time and oxygen values.

Sea urchin data
Oxygen levels in the sea water are recorded from dinner time into the evening--there is no rest for a busy scientist.

Working Hard for Science

I am so impressed with how dedicated the scientists in McMurdo Station are. Amanda and I collected data until 8 pm--well past dinner! Amanda had been preparing for this experiment for months and it was exciting to be part of getting the results.

Conduct Your Own Sea Urchin & Ocean Acidification Lesson

Amanda not only conducts important research on sea urchins, she also translates her research into inquiry-based lessons for students! Check out the current issue of Science Scope to find a hands-on lesson by Amanda Kelley on sea urchins and climate change (membership is required to access the journal).

Ice Picture of the Day

Today's Picture of the Day is about larval sea urchins! Click here to download a PowerPoint Slide: 10_icepod.pptx

Ice Picture of the Day, day 9
The Ice Picture of the Day compares sea urchins to butter.

Brought to you by...

Today's journal is brought to you by Dana Carnemolla's class at Eton House, in Surabaya, Indonesia. Thank you for following along with us!

Eton House Penguin
Today's journal was brought to you by Dana Carnemella's class from Eton School in Indonesia.

Details
Author
Michelle Brown
Date
Location
McMurdo Station
Expedition
Human Impacts in Antarctica 2015
Weather Summary
Sunny
Temperature
14 F
Wind Speed
12 knots
Wind Chill
-1 F

View Comments

Documents
Attachment Size
graphing_a_vertical_profile_in_mcmurdo_sound.docx547.67 KB 547.67 KB
10_icepod.pptx283.72 KB 283.72 KB

Comments

Tue, 11/17/2015 - 13:01

Sigrid

Hi-thank you so much for taking the time to answer my questions!
1.) Why did you decide to study sea urchins when in Antarctica?

Tue, 11/17/2015 - 14:50

Andrew

1) How long goes it take for a Sea Urchin to grow to its adult phase?
2) What average temperature is it in Antarctica?

3) Does the salt level differ in Antarctica than in the U.S.?

4) What other sea animals are found in Antarctica?

5) Does the water temperature increase or decrease as an iceberg melts?

Wed, 11/18/2015 - 02:09

Zoe

1.) Is it hard for Sea Urchins to survive in such cold waters such as in Antarctica?
2.) How does the forming of the Sea Urchins body differ in Antarctica than in other warmer climates?

Wed, 11/18/2015 - 12:16

Ibrahim

Hey team! I wanted to know what Amanda has been able to learn and conclude from her sea urchin experiments on how they respond to ocean acidification and warmer temperatures? What new information has been extracted from this experiment?

Wed, 11/18/2015 - 14:25

Michelle Brown

status: 1Hi Sigrid,

I asked Amanda Kelley, the scientist who works on sea urchins to answer
your question--here is her response:

Good question! I chose the sea urchin because it is a dominant species here
in Antarctica. Also, they are calcifiers, which means they have calcium
carbonate structures that are similar to bones in humans. Clams, snails and
other marine invertebrates use it as a frame for their soft bodies. Ocean
acidification makes it hard for animals to make their shells. Also, it can
affect how animals grow and develop.
I hope that was helpful!

Wed, 11/18/2015 - 14:38

Susan

If the sea urchins grow slower in colder water then how are they even able to live in such a cold place like Antarctica and wouldn't their lives be shortened if they live in a colder area than a warmer one?

Wed, 11/18/2015 - 15:25

Michelle Brown

status: 1Hi Andrew,

Great questions! Below are responses:

1) I asked Amanda Kelley (the scientist studying sea urchins) about your
question -- this is what she said: "I'm not sure how long it takes
Antarctic sea urchins to become adults. However, we know that it takes 1-2
years for this species, *Sterechinus neumayeri* to become juveniles."

2) The average temperature in Antarctica depends on where you are--it is
significantly colder up on the ice shelf, which can be up to a mile high!
The mean annual temperature up on the ice shelf (interior) is -57 degrees
C, (-70.6 degrees F). In McMurdo Station temperatures range from -26
degrees Celsius in August and -3 C degrees in January.

3) The salt level in the water in Antarctic is similar to the levels in
other parts of the world, including the U.S. Although there are only small
changes in salinity, it does play an important role in water cycle and
ocean circulation. You can see how salinity is different in different parts
of the world here:
http://science1.nasa.gov/earth-science/oceanography/physical-ocean/sali…

4) There are many types of organisms that live in the sea in Antarctica!
There are at least 235 marine species in Antarctic waters. Up to 155,000
animals can be found in 1 square meter of certain areas of the seafloor!

5) This is another great question which I asked my research team about. An
iceberg is made of fresh water, which freezes at a slightly warmer
temperature than salt water. Therefore, as an iceberg melts, the fresh
water should be slightly colder than the salt water. However, this
difference is so small that it is not noticeable.

Wed, 11/18/2015 - 23:25

Michelle Brown

status: 1Dear Zoe,
Thank you for asking such great questions! It is not difficult for sea
urchins to survive in cold waters. In fact, I asked the scientists studying
sea urchins (Amanda Kelley) about this, and she replied:

The Antarctic sea urchin has evolved metabolic efficiency in response to
the cold. Basically, these urchins can utilize energy from food 25 times
more efficiently than other organisms. So they can eat very little and make
that energy last longer than other organisms do.

In regards to how their bodies form -- I believe they form similarly, just
at a much slower pace. I will follow up with Dr. Kelley and make sure I am
correct. Great job asking thoughtful questions! Perhaps you should consider
becoming a marine biologist!

Thu, 11/19/2015 - 10:26

Michelle Brown

status: 1Hi Ibrahim,

Great question! I had to ask Dr. Kelley, here's what she wrote:
The samples that I collected from last season's research were sent to a lab
that sequenced the messenger RNA-mRNA. mRNA are small molecules that genes
produce that get translated in to proteins. I am interested in
understanding what genes were turned on and which were turned off while the
larvae were exposed to ocean acidification conditions. It will be a few
more months before we have the results. One thing we do know is that larvae
are smaller in over all body size when exposed to OA. That can have
consequences, such as the potential for increased predation, and slower
swimming speed, which can reduce there feeding rates. This work is still
very new so we have a lot to learn!

Let me know if you have more questions on this--I'm learning here as well!

Thu, 11/19/2015 - 17:17

Chrissy

1. What type of sea urchin are you testing.2. How do the sea urchins survive in such cold temperatures?

Thu, 11/19/2015 - 20:28

Michelle Brown

status: 1Great thinking Susan! However, urchins have adaptations to let them succeed
in cold waters. Here is what Dr. Kelley says: "The Antarctic sea urchin has
evolved metabolic efficiency in response to the cold. Basically, these
urchins can utilize energy from food 25 times more efficiently than other
organisms. So they can eat very little and make that energy last longer
than other organisms do." I hope that helps answer your question!

Sat, 11/21/2015 - 23:34

Michelle Brown

status: 1Hi Chrissy,

Great questions! I asked Dr. Amanda Kelley what species of sea urchin she
was testing. Here is what she said:
"My study animal is call *Sterechinus neumayeri,* the Antarctic sea urchin.
The Antarctic sea urchin is very efficient turning food, in this case
diatoms (mostly) into metabolic energy. They can survive longer on less
food than urchins from temperate and tropical oceans."
The urchins are able to survive in cold temperatures because of their
ability to change their metabolism!

Tue, 06/21/2016 - 17:22

Pauline

HelloI am a volunteer at the Oceanic Insitute in Hawaii and I am very interested in how Amanda Kelley is approaching her observation of sea urchins - is there anyway that I can email her directly?

Fri, 11/13/2015 - 10:40

zak

how do they survive in the cold?

Thu, 06/23/2016 - 17:18

Michelle Brown

Dear Pauline,
Yes--Dr. Kelley is an amazing scientist who would be happy to speak with
you directly. You can email her at: alkelley@alaska.edu and she is
expecting your email. Thank you for reading and responding to the post and
best of luck at the Oceanic Institute!

Sincerely,
Michelle

Fri, 11/13/2015 - 10:41

Zoe Currall

Why do they grow feet? I do not know much about sea urchins. I thought they were a different thing. It kind of looks cute though-Zoe.

Sat, 11/14/2015 - 21:56

Michelle Brown

Hi Zak,Thank you for a great question! Sea urchin larvae, like other organisms that live in the freezing waters of Antarctica, have adaptations that allow them to survive. I will talk to Amanda and find out exactly what these adaptations are for you--stay tuned!