July 13, 2012
We just finished the last collection site of the cruise and are heading back to Alpena. The rumor on the ship is there will be a swim call when we reach Thunder Bay. The lesson of the day is Brandon’s story of the ship. The Guardian is welded, pinned and bolted together. Should a small crack appear in a weld seam and a small amount of water is taken on there might not be a great concern. However, at some point when the wrong weld, or a dozen bolts or a hundred pins are removed, the ship begins to sink; now there is a problem. Our ecosystems are like a ship. They are made up of hundred if not thousands of organisms. The loss of one or two may not create a serious problem. However, at some point the removal of one critical species or a larger group of organisms will cause the destruction of the ecosystem. The Great Lakes have shown themselves to be a very resilient set of ecosystems. They have withstood many different attacks by many different organisms. They have weathered the loss of dozens of native species. How do we know, however, if the next invasive or the next extinction will cause the ship to sink?
July 12, 2012
Today we woke up in the Georgian Bay for our study of two station on the north side of the border. The previous night we had collected Mysis and larval fishes from a location just inside the bay. This morning we collected another sample of larval fish at the same location. We identified a few burbot and a ton of rainbow smelt. While we were expecting to collect more larvae during the night tow, we actually found over twice as many during the day.
After we arrived at the second Georgian Bay station we got out the ship’s ROV and took it down to the bottom. After Marine Tech Johna got everything working, she gave any of us that wanted to an oportunity to fly it. Bo, Doug, Erin and Bobbi each took it for a spin. After getting used to the controls, they each were able to get it to do what they wanted it to (more or less). Doug even collected a few quagga mussles from a submerged log. Dr. Jude got excited when we scared up some gobies, too.
July 11, 2012
A beautiful day awaited us this morning with almost placid water and clear skies. As many more samples are being collected and piled up, students work extra hard in the laboratory to identify fish larvae, algae, and zooplankton. Imagine having to identify small animals and plants only microns or millimeters long! To identify zooplankton, one must count the amount of little tails. This required some effort to look in a microscope at things in liquid on a moving ship! Zooplankton that has been identified include daphnia, holopedium, leptodiaptomus, senecella, and acanthocyclops.
We also learned about the hydrolab, which is an instrument that teachers could borrow for free from SeaGrant. This will allow students to measure water quality in our home areas. The device is very high tech, because it measures various water quality parameters at once, send them to a computer, and allows students to work with data on a computer. This way they could compare data they have collected at school, with the data we collected on the R/V Lake Guardian.
To our dispair, we collected a large amount of quagga mussels in the middle of Lake Huron. This surprised us, as the water is very deep (88 meters). We also took our first secchi disk reading and ran out of the 23 meters of cord. So, we have over 23 meters of visibility in the middle of Lake Huron. This clarity is somewhat concerning, as this shows the lake is getting more oligotrophic (having less nutrient base). During a lecture from Jim Lubner today, we learned that the Compensation Depth of water is three times the secchi disk reading. This means that light could reach 69 meters in the water at the point of our testing. Plants, such as phytoplankton, could live down to the 69 meter mark. No wonder we found quagga mussels!
The welcoming and accomodating staff of the ship, including the Captain himself, invited us to jump into the Canadian waters of Lake Huron. Once recovered from the cold shock, the water felt refreshing on the warm summer day!
A small crew of us remained awake to make a midnight mysis collection. The winds were calm, the stars bright. The caffinated ones stayed in the lab until the wee hours of the morning until the last mysis was counted; the rest of us went to bed. A short night in bed, the 9:00 collection station came quickly this morning.
July 10, 2012
The third day dawned early with the washing of the pesky May flies at 5:45 am. The Zodiac was deployed shortly after to “abduct” three visiting dignitaries from Tawas, Michigan. Our abductees were David Lusch, Michigan State University; Jim Diana, Director of Michigan Sea Grant program; and Al Taylor, Michigan Department of Environmental Quality. After breakfast David Lusch gave us a two hour lecture on the geological origins and history of the Great Lakes.
We then collected samples of algae, zooplankton, fish larvae, fish collection, as well as using gill nets to collect larger fish. We ate a delicious lunch and returned to our post on the stern of the ship to assist Al Taylor with his soil sample. The soil sample was taken using a tool called the spider core from the center of Saginaw Bay. We came inside the Lake Guardian to remove the stomachs from the fish to see what the fish have been eating.
After the appetizing dissection of several species of Lake Huron fish (White Suckers, Perch, Gobies, and Trout Perch), we then proceeded to the cafeteria to partake of some delicious fish. Then we enjoyed a lecture on “Doom and Gloom” by Dave Jude from the University of Michigan.
We ended our day with a general discussion on the impact of PCB’s and The Decline of Diporeia. For some of us the day is not over, they will do a midnight Mysis tow.
Hi MOM and DAD!!!!!!!!!!!!!!!!!
Pam Evans, Bobbi McConnell, and Regina Mueller