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!