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Science team members prepare the box core for an evening launch. Click on image for larger view.
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Playing in the Mud!
September 18, 2001
Tanya Podchaski, Teacher
Bernards High, Bernardsville, New Jersey
"To me there is something completely and satisfyingly restful in that stretch of sea and sand and sky -- complete peace and complete fulfillment."
-- Anne Morrow Lindbergh
The night was quiet as most of the ship had gone to sleep, but Rose Petrecca, Hovey Clifford, George Hampson, and several crew members were on the stern of the ship sending down a 1/4-m-square box core into the deep blue sea. It would take about 45 min for it to descend 2,100 m to the ocean bottom. Once on the bottom, the shovel digs down, captures a 15-cm surface core sample, and begins its 45-min ascent.
Once the box core is back on board, the scientists take it apart. There are 24 subcores in the box, but they will seive, number, preserve, and box only the inner nine. Once the samples are stored, they are taken to the lab, sifted, and analyzed. Scientists then compare the data to previous data collected from the same site.
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Log author Tanya Podchaski seives through a mud subcore. Click on image for larger view.
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Rose Petrecca's group is contributing to nearly 20 yrs of ongoing research at the U.S. Minerals Management Service's (MMS) Mid-station 6 long-term study site. Between 1982 and 1983, MMS sent down six different box cores to get a baseline of the resident fauna. In 1983, they found close to 800 species in the mud. To everyone's surprise, this benthic habitat is as diverse as any rainforest.
I was intrigued when I heard about the mud's amazing diversity. The group would be doing three different box cores at the MMS site, so I decided to stick around and help. I had no idea what I was in for! Once the box core was up, everyone manned their stations. I was a seiver and preserver. When the subcores came out, Ms. Petrecca gave me the top 10 cm.
I took the sample to my seiving station and rinsed off the top 0-3 cm of mud into a specimen jar. I then took the remaining mud and poured it into a seive. I had to wash the mud with water and filter it before putting it into another jar. It was amazing how many critters inhabited this little scoop of mud! I saw foraminiferans (tiny, white-shelled invertebrates), crustaceans (baby crabs, lobsters, and shrimp), and polychaetes (marine worms). Many more creatures could not be seen with the naked eye, but the ones I did see were incredible. I had so much fun seiving the first box core that I stayed around and worked on the other two. Basically, I worked all night long in the mud, and by daybreak, I was a happy, muddy mess! I didn't turn in until 4 am Wednesday morning. I was tired, but I had witnessed one of the most diverse habitats on Earth.
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Chief Scientist Dr. Fred Grassle holds the "excellent specimen" that Alvin retrieved from the depths. Click on image for larger view.
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While the mud business was going on, the deep submergence vehicle Alvin had gone out on a dive and returned. The biggest thrill of the dive was the "big animal" they had caught. Everyone, including chief scientist Dr. Fred Grassle, anxiously awaited Alvin's return to deck so they could see this find. When the sub was securely back in it's "garage," Dr. Grassle walked over to the specimen box and took a look inside. "Excellent specimen," he said. Then he filled a bucket with water to place the crature in, telling us that it was some sort of sea anenome.
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Rose Petrecca
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Interview with Rose Petrecca
Benthic Ecologist
Ocean Explorer Team: How did you get interested in benthic ecology -- the study of organisms living on, or in, the ocean-floor sediments?
Rose Petrecca: It's hard to know where to begin. When I was seven yrs old I loved watching the TV show Sea Hunt. As a result, I wanted to learn to dive, although my mother was very afraid of the water and tried to discourage me. When I was 14, I finally was allowed to take diving lessons, and became totally enthralled with the underwater world. I knew I wanted to study marine science. When it came time for me to go to college, I looked around for a school that offered such a program -- not many did back in the 1970s. I decided to enroll in Southeastern Massachusetts University in Dartmouth, MA. During the summers, I worked with my former diving instructor, who had started a marine contracting company. That's when I got my captain's license. Sometimes I worked for environmental consulting firms. When I graduated from college, one of those firms, Marine Research Consulting, offered me a permanent position in its benthic laboratory.
Ocean Explorer Team: You have a nickname, "The Worm Queen"! How did you come to specialize in studying and identifying worms?
Rose Petrecca: After working for the consulting firm for four yrs, in 1980 I took a position working for Dr. Fred Grassle in his lab at Woods Hole Oceanographic Institution. My job was to help sort and identify benthic invertebrate organisms, for example, crustaceans, amphipods, mollusks, and worms. I worked with three other people, and none of them liked to identify the polychaete worms, so I did. I loved it and I've never looked back. I've worked with Dr. Grassle for 22 yrs now.
Ocean Explorer Team: Yesterday, you went down in the submersible. How many times have you dived in Alvin?
Rose Petrecca: Yesterday was my 26th dive.
Ocean Explorer Team: What was your most memorable Alvin dive?
Rose Petrecca: We were diving off the coast of Ecuador, exploring a part of the Galapagos Rift now known as the "Rose Garden." When I looked through Alvin's porthole to see my first hydrothermal vent and the tubeworms that lived there, it was incredible. Photographs and videos simply do not capture the true brilliance of the colors. The vivid red plumes of the worms, and the contrasting whiteness of their tubes, was just breathtaking.
Ocean Explorer Team: What advice might you have for young people interested in scientific careers?
Rose Petrecca: Do excellent science, and have fun doing it. I am truly blessed. Every day, I look forward to coming to work with wonderful people and doing what I love.
Interview by Holly Richardson Donovan and Tanya Podchaski of the Ocean Explorer Team.
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