Elizabeth Bullock: We Are Underway! December 11, 2011

NOAA Teacher at Sea
Elizabeth Bullock
Aboard R/V Walton Smith
December 11-15, 2011

Mission: South Florida Bimonthly Regional Survey
Geographical Area: South Florida Coast and Gulf of Mexico
Date: December 11, 2011

Weather Data from the Bridge
Time: 2:30pm
Air Temperature: 24.5 degrees C (76 degrees F)
Wind Direction: 65.9 degrees east northeast
Wind Speed: 15.8 knots
Relative Humidity: 78%

Science and Technology Log

Today is the first day of the research cruise.  The R/V Walton Smith left its home port in Miami, FL this morning at about 7:30am.  After a delicious breakfast, the crew and scientific party received a safety briefing from Dave, the Marine Tech.  We learned about the importance of shipboard drills and we were shown the location of all the safety gear we might need in case of an emergency.  This ship works like a self-contained community.  The crew of the ship must also be the policemen and firemen (or policewomen and firewomen).

After our safety briefing, the science party went outside to our first station of the day.  The first piece of equipment we put into the water was a CTD.  The CTD is named after the three factors the equipment measures: conductivity, temperature, and depth.  The CTD will be deployed at precise locations along our route.  Since they conduct this research cruise twice a month, they can see if conditions are changing or staying the same over time.

Here I am, reading the data that came up from the CTD.

This is the CTD, which measures conductivity, temperature, and depth.

Question for students: What is the relationship between salt and electrical conductivity?  If the salt content in the water increases, will it conduct electricity better or worse?

The next piece of equipment we deployed was the Neuston Net.  This net sits at the water line and skims organisms off the surface of the ocean.  The net is in the water for 30 minutes at a time.  After bringing the net onto the deck, the fun part starts – examining the contents!  Our Neuston Net had two main species: moon jelly (Aurelia) and sargassum.  The term sargassum actually describes many species, so the scientists on board will study it carefully in order to classify which kinds they caught in the net.  Sargassum is an amazing thing!  It is planktonic (which means that it floats with the current) and it serves as a habitat for bacteria and small organisms.  Since it is such a thriving habitat, it is also a great feeding ground for many different species of fish.

Once we emptied the contents of the Neuston Net, Lindsey and Rachel, two of the scientists on board, began to measure the quantity of each species they caught.  In order to measure the weight of the moon jellies, they used the displacement method.  This is because we can’t use regular scales onboard.  Here are the steps we took to measure the moon jellies:

1)      We poured water into a graduated cylinder and recorded the water level.  For example, let’s say that we poured in 100ml of water.

2)      We put a moon jelly into the graduated cylinder and recorded the new water level.  For example, let’s say that the new water level read 700ml.

3)      We subtracted the old water level from the new, and we could tell the volume of the moon jelly we had caught.  For example, based on the numbers above, we would have caught a 600ml moon jelly!

Lindsey examines what we caught in the Neuston Net.

Both the CTD and the Neuston Net will be deployed many times over the course of the cruise.

 

Personal Log

Despite a bit of seasickness, I am having a wonderful time!  Everyone on board is very welcoming and happy to answer my questions.  Everyone is so busy!  It seems like they have all been working nonstop since we arrived on board yesterday.

Answers to your questions

First, let me just say that these are great questions!  Good job, Green Acres.  Here are some answers, below.

1)      How do the currents make a difference in the water temp?  The currents play a major role in water temperature.  In the Northern Hemisphere, currents on the east coast of a continent bring water up from the equator.  For example, the Gulf Stream (which is a very important current down here in Florida) brings warm water from the tropics up the east coast of the United States.  This not only keeps the water temperature warm, but it also affects the air temperature as well.

2)      How does the current affect the different algae populations?  Currents regulate the flow of nutrients (which phytoplankton needs to survive).  Strong currents can also create turbidity, which means that it stirs up the water and makes it harder for light to penetrate the water column.  As you know, phytoplankton rely on sunlight to grow, so if less light is available, the phytoplankton will suffer.  I’m told by Sharein (one of the phytoplankton researchers) that algae are hearty creatures.  This means that as long as the turbid conditions are temporary, algae should be able to thrive.

Stephen Bunker: Sargassum Experiments, 21 October 2011

NOAA Teacher at Sea
Stephen Bunker
Aboard R/V Walton Smith
October 20 — 24, 2011

Mission: South Florida Bimonthly Regional Survey
Geographical Area: South Florida Coast and Gulf of Mexico
Date: 21 October 2011

Weather Data from the bridge

Time: 11:30 AM
Wind direction: Northeast
Wind velocity: 8 m/s
Air Temperature: 23° C (73° F)
Clouds: cirro cumulus

Science and Technology Log

That's me tending the Neuston net as it's being towed aside the R/V Walton Smith.

One of the many experiments we are doing on board is to learn about a plant that grows in the ocean called Sargassum. This tan plant floats near the surface and along in the current. It grows throughout the world’s topical seas. It can grow into large mats the and can be as large as boats and ships. Sargassum provides an environment for distinctive and plants and animals that are not found other places. These ecosystem rafts harbor many different organisms.

On the third stop of the CTD cycle we drag a Neuston net along side of the boat. For 1/2 hour, night or day, the boat takes a slow turn as we drag the net along the surface as we collect samples.  Almost all of the animals below are what we have found in the Neuston net.

We’ll haul in the net and remove the contents. We’ll first try to get all of the animals out. The animals usually don’t survive but every once in a while we can save them (see below for some of the animals we captured with the net).

We’ll next sort the plant life that we collect in the net. Of course we are looking for Sargassum, so we will separate out all of the sargassum.

So, how do you measure what you get? We measure it by volume much like our mom’s measure shortening for cookies. We will fill up a graduated cylinder part way with water, put the samples from the net into the cylinder and then measure how much water they displace.

For example, if we put 2500 ml of water in the graduated cylinder, then put Sargassum in the cylinder, the water level now measures 5500 ml . We then know that there are 3000 ml  (5500 ml – 2500 ml = 3000 ml) of Sargassum by volume measure.

Everything we collect from the net, we measure and record.

Personal Log — Animals I’ve seen

• Flying Fish— Yes, believe it or not, there are fish that fly. Last night as were preparing to lower the CTD, I noticed silvery-blue streaks in the water. One of the scientists with me explained that they are Flying Fish (Exocoetidae) and the lights of our vessel attracts them and many other types of fish to the surface at night. As soon as she explained this, one of them shot out of the water and glided about a meter and ducked back into the water. Read more about Flying Fish here.
• 

  This fish was found as we unloaded the Moch net.

  Rock Fish — Each time we drag the Moch Net for the Sargassum survey, we can expect interesting things. Last night we captured a type of Rock Fish.

• Spotted Eel — We also found an eel that has white spots. I tried my best to see if I could more specifically identify it. We have saved it in an aquarium on board the R/V Walton Smith.
• 

  Help identify this mystery fish. Make a comment below if you think you know what it is.

  Mystery Fish — This fish has many of us stumped. It has a long nose but when the fish opens its mouth, you can see that the pointy part is connected to its lower jaw. Put your investigative skills to use and help me identify the fish. Post a comment if you think you know what it is. For an enlarged view, click here.

• Moon Jellies — Many people call them Jelly Fish but actually they don’t belong to the fish family at all. They don’t even have a backbone. When we carefully picked these animals up, with gloves on of course, it feels like picking up Jello with your hands; it just slips through your fingers. You can find more about Moon Jellies, Aurelia aurita, at the Monterey Bay Aquarium. You can also find general information about Jellyfish at National Geographic Kids.
• 

  This eel was found when we were collecting Sargassum.

  Sharptail eel — It’s about half a meter in length and squirms all over. The scientist studying the Sargassum, has saved it in an aquarium so we can observe it. Its scientific name is Myrichthys breviceps.

• Honey Bee — Believe it or not a honey bee joined us. There was no land in view and a honey bee landed on me. The wind must have blown the bee to sea and it was probably very happy to find a place to land that was not wet.

• Porpoise — We also call these dolphins. Sometimes a pod of porpoises will get curious and  investigate our boat. They will circle us, swim along side and even ride our bow wave.