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Early on in the research cruise, a scientist reported that while he used the head (the restroom) in the middle of the night with the lights off, he observed a bioluminescent glow in the toilet bowl. This observation was also confirmed by other scientists on following evenings. While it was not consistently observed every night, it did occur. What caused this strange phenomena? Bioluminescent plankton is the culprit! The ship’s toilets run on a salt water system so when water is pumped in, some of the tiny, one celled organisms called dinoflagellates make their way into your toilet. They can emit a short blue-green flash of light when the water is agitated by such things as flushing the toilet. If present in enough numbers a faint glow can be observed.
Many marine organisms possess bioluminescence. While it is not as common in the upper portion of the ocean called photic zone which receives sunlight. It is estimated that approximately 90% of organisms in the deep ocean, between 200 and 1000 meters, use bioluminescence in some form or another. It may be used for finding a mate, evading predators, or attracting prey.
Deep sea organisms have special light producing structures called photophores. Fish may have rows of these photophores along the bottom (ventral) side of their body and under their eyes. Some types of angler fish have a bioluminescent lure which dangles above or below the fish’s mouth (a barbel) to attract prey. Although most marine bioluminescence is not bacterial, the bioluminescence in angler fish lures is created by bacteria.
Teacher At Sea,
Christia Hewlett
Here are a few more pictures taken by me. The previous pictures were taken by Dr. Dante Fenolio.
Photophores near the eye.
Here you can see rows of photophores along the bottom of the fish.
The CTD device takes water samples at different depths. CTD stands for conductivity, temperature and depth. Other measurements can be taken if additional sensors are added for things like oxygen level, salinity, pH or chlorophyll. From the computer station inside the ship, scientists monitor the water that is passing through the CTD as it is lowered into the depths. They can find out what layers of water have the most chlorophyll, whether there is an oxygen minimum zone or other needed data. These layers are then targeted as water collection points when the CTD is brought back up to the surface. The CTD has a number of bottles that are deployed open. This allows water to pass continuously through the bottles as it is moving in the water column. At specific depths the scientist instructs the device to close one or two bottles to collect the water. The scientist running the CTD can communicate with the crewman running the winch and the device can be raised or lowered to the desired depth. Typically the CTD is sent down to 1500 meters. Data are collected from a station at least two different times, once in the daytime around 6 am and once at night around 6 pm.
The CTD
In addition to the abiotic factors studied through the water collection, information can also be determined about biotic factors. One of the scientists, Dr. Cole Easson is studying microbes from the different layers of ocean water. He filters the water from the different layers and extracts the microbes onto a filter. The filters are taken back to the lab at home where he sequences the DNA of the microbes. A single sample can contain over 7,000 unique microbes. From the first two DEEPEND research cruises he generated 33.5 million sequences.
Dr. Cole Easson
Another scientist Travis Richards, is filtering water samples to collect data on primary production. This allows him to establish what is the base of the food web and correlate this information to his study of stable isotope analysis with fish. This allows him to predict at what trophic level each animal is located in the food web.
Filtering water from the CTD
Yesterday when we were pulling the MOCNESS we saw what appeared to be an abandoned boat. This observation was called into the US Coast Guard. After finishing the trawl, we circled back by to take a look and make sure there was no one aboard. The makeshift boat was filled with containers with water and leftover supplies. It had metal ribs that were filled with some type of foam and then covered in a tarp. A motor had been attached to it. We hope that the people on board reached safety. Perhaps the boat landed and then floated back out to sea or they were picked up by another vessel. Abandoned boats are one type of marine debris. Luckily other than the boat we have not observed much in the way of marine debris. I personally have only seen 1 or 2 small pieces of trash floating in the water.
While we were checking out the boat it was noticed that the floating structure created something for small fish to congregate around. This attracted some larger fish. There was a school of Mahi-mahi or dolphin fish schooling. Several of the fishermen on board were able to grab a fishing pole and some even caught a fish. Here is a picture of the largest one caught. We are looking forward to dinner tonight.
Travis and his catch
Teacher At Sea,
Christia Hewlett
Who are the super scientists on board? Here is a little information about each of the scientists that are aboard for this research cruise and some action shots of them at work.
Dr. Tracey Sutton from Nova Southeastern University is the Chief Scientist for the DEEPEND Consortium. He leads up the project and sets the plan for what the group of scientist are focused on. On the cruise he makes decisions about where we will be doing our specimen collections if we have to make any modifications to the original plan due to weather or equipment issues. Once the organisms are brought on board he does fish identification. He also removes some of the fish organs so that they can be processed and tested for the presence of hydrocarbons.
Dr. Jon Moore is from the Honors College at Florida Atlantic University where he studies Marine and terrestrial ecology. He specializes in deep sea fish fish ecology & evolution. On the trip he is serving as a fish taxonomist identifying many of the interesting fish finds.
Dr. Tammy Frank is a biological oceanographer from Nova Southeastern University.
She studies deep-sea ecosystems specifically vision and bioluminescence. For the DEEPEND project she is leading studies on crustacean abundance and diversity.
Dr. Mike Vecchione is a zoologist who works for NOAA as the Cephalopod Curator at the Smithsonian Institution’s Museum of Natural History. He is also an adjunct professor at the College of William & Mary’s Institute of Marine Science.
Dr. Heather Bracken-Grissom from Florida International University specializes in crustacean genetics. At FIU she teaches genetics and invertebrate zoology. She is using genetic diversity as a way to measure ecosystem health and recovery.
Dr. Joseph Warren Stonybrook University uses Hydroacoustics to study the migration of marine life. Here he is determining the density of different species of fish to correlate with the acoustic findings.
Dr. Kevin Boswell from Florida International University studies hydroacoustics as well. Here he is preparing the wombat to be attached to the CTD device. The wombat can collect more specific data than the regular acoustic transducer. Dr. Warren and Dr. Boswell can use this information to direct a more targeted trawl that is aimed at specific layers of animals.
One of the scientists, Dr. Cole Easson from Nova Southeastern University is studying microbes from the different layers of ocean water that have been collected by the CTD. He filters the water from the different layers and extracts the microbes onto a filter. The filters are taken back to the lab and the DNA of the microbes is examined. Microbes are then divided into two groups; one group which occurs in the photic zone and the other group occurs in the deeper zone where the light does not reach.
Here is Gray Lawson recording data in his science log book. He is a marine technician employed by (CSA) Continental Shelf Associates and contracted by the DEEPEND project to run the MOCNESS. His work as a marine technician has taken him to many interesting locations such as Cameron, Israel, Qatar and the Caribbean.
Dr. Dante Fenolio is from the San Antonio Zoo where he serves as the Vice President of Conservation and Research. He is the Outreach & Filming Lead for the DEEPEND Project. He is tasked with capturing all of the unique finds on the cruise and documenting the work of the scientists with film and interviews.
April Cook is the DEEPEND Project Manager from Nova Southeastern University. While at sea she is in charge of sample data collection. April is the glue that helps hold the project together. She sets up the logistics of the project keeps everyone on task, making sure that all information is logged into the database and all samples are labelled correctly so that the samples will generate valid comparable data.
Graduate Students
Max Weber is a masters student at Texas A&M University at Galveston where he focuses on fish genetics. Some species are difficult to determine differences in appearance only and must be determined genetically.
Travis Richards is a PhD student at Texas A&M University at Galveston where he is studying food web ecology. He is helping to process fish genetics. He will be using stable isotope analysis to examine the structure of the food web in the marine environment.
Jacki Long is from the University of South Florida College of Marine Science where she is completing her masters in Optical Oceanography. She uses the CTD to collect information about the water column, uses the back scattering device to information about particle size & abundance, and collects optical data to ground truth satellite information from remote sensing devices.
For more information about each of these scientists please click here to check out their biographies available on the team page on another portion of the DEEPEND website.
By-catch is defined as the unwanted species of fish or marine creatures who are caught in a net by fisherman. Some students ask about what was kept from the nets vs what was thrown back in the water. On this trip there is no such thing as by-catch. Everything that is caught will be used and analyzed to help paint the picture of what is going on in the different layers of the ocean. Above is an example of what might come from just 1 net in the trawl (which has 6 nets total). This varies with depth and whether the trawl was done in the daytime or night.
Everything is kept for abundance and diversity measurements. However species are needed for a number of other projects - DNA, stable isotopes, parasites or hydrocarbons.. Before coming on the research trip scientists collaborated and identified the species needed for these projects and these specimens are processed immediately on board the ship after each trawl. The rest of the animals are stored in formalin and will be analyzed back on land at different university labs.
Here is a picture of the different tags that are placed in the specimen sample dishes. Each sample is given a net number, an identification tag with the genus and species name. The N tag tells what net the specimen came out of. The processed samples receive a printed label with more specific details including latitude, longitude, date and trawl number. This makes sure the correct information is stored with each specimen. This is critical when you are dealing with tens of thousands of specimens.
Here is a picture of how the scientist begin the identification process and sort organisms into broad groups.
Crustaceans!
Cephalopods
Fish ready to be identified.
Here are some more pictures after the specimens have been sorted and identified. They are then processed and stored.
Fish sorted and identified. Classified crustaceans.
Teacher At Sea,
Christia Hewlett