NOAA Teacher at Sea
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 2, 2011
Science and Technology Log
Life of all sizes
Today I woke up late because the ship rocked me back to sleep many times. When I stumbled out of the berth, people were busy working. They had already released a seaglider that is owned by the University of Hawaii. This is a machine that looks kind of like an airplane. It collects information about the ocean and relays it back to land via satellite.
It goes down, collects data, comes back up to send data to land, then goes back down again for more data, and on and on. The glider is collecting information on ocean temperature, salinity, and phytoplankton (through fluorescence). There is also a hydrophone attached which is “passive” acoustics. This means that the hydrophone can hear sounds, but does not “actively” send out a signal. With passive acoustics they can hear cetacean sounds, and can possibly identify species, but would have less luck understanding *where* the animals were.
Everyday samples of ocean water are taken. This is done using a CTD (conductivity, temperature, and depth) machine. It is cast off several times a day. The CTD is dropped into the ocean using a crane and winch. It is sent down to 1,000 meters, and water is collected at specific depths between 200 meters and the surface. Most of the biological signal they see is in the upper 200 meters of the water, which is roughly the depth of the Euphotic (or Sunlit) Zone.
The CTD is attached to the ship’s computers with wire inside a cable. It sends signals to the computers so the scientist can keep track of the where it is, and “fire” one bottle (Niskin Bottles) at a time. This means closing the bottle’s lid so it can hold the water it has collected. After each one is fired, the water from all the different depths is lifted to the surface and collected for sampling. Scientists then filter the seawater to get a concentrated sample of phytoplankton cells using a small round piece of paper. These filters are put in a liquid called acetone and kept cold (-20 degrees celsius) for 24 hours and then fluorescence levels are measured in the lab. This gives them an idea of how much phytoplankton is located at different depths. Other samples are put in liquid nitrogen, and sent back to the University of Hawaii where they will use specialized equipment (High Performance Liquid Chromatography) to identify the types of phytoplankton.
Another group of scientists went out on a small boat to look for cetaceans (Spinner dolphins and False Killer whales). They will be taking pictures and collecting samples of the mammal’s “skin” to test it for various reasons. These can tell them what the dolphins are eating and where they are eating. Scientists look at their genetics to help them determine the amount of dolphin species and how different groups are related to each other. Today they were able to see striped dolphins which are very beautiful and not as easy to find.
There are also trawl operations at certain places called stations. This is where the ship releases a net and scoops up small organisms for studying. We saw a lot of shrimp, squid, and fish called Myctophids. They were weighed, sorted by types, and counted.
It has been an exciting day! There are many different activities going on at the same time, so I am glad my time onboard will be two weeks. I have met scientists, student interns, and employees of NOAA. Everyone works together on the ship whether they are from New York, Florida, California, Rhode Island, New Jersey, or Hawaii. Eating in the galley is like going to grandma’s house for dinner. I am looking forward to tomorrow’s adventures when I hope to learn more about the acoustic operations and how they are tracking fish.