Marine Biology Trip Day 2 – Connor Lehman


Today was our second day of diving and our first day of project dives. Our project is to measure the relationship between the length of the diameter of a barrel sponge and the speed the sponge filters water. Before we left the dock, our dive instructor, Beth, and our group went over our materials for the dive. We brought a measuring tape to measure the diameter and height of the barrel sponge, underwater paper to record our data, and syringes containing the dye we used to see when and where the water is filtered in the sponge. Before we dove, we had to tape the syringes closed, as they would leak with the small opening being exposed. When we reached our first site, Ginger Island’s Steps, we descended and began to look for barrel sponges. Within 5 minutes we found a huge patch of barrel sponges. We chose 3 to measure, measured them, and placed the dye around them in order to time the filtering process. We recorded the data and ended our first dive. At the second site, Ginger Island’s Backside, we did not find any sponges to take data from. Rather, we went looking for reef sharks and saw about five different ones swimming around us, circling us looking for food. Some of the groups focusing on their research were so focused on their own projects that they didn’t even notice the sharks swimming a couple feet away from them. As we finished our dives and ate lunch to finish the morning, we went and hiked the Baths, which was a great experience. The rock formations all made by nature and the air pockets that were also naturally created blew my mind. It truly showed me God’s work physically and the overall beauty of nature. 
From our dives today, we learned that the process of our project is efficient and works well. We also learned that our hypothesis, being that the larger the diameter means the faster the process of filtering water, seems to be completely wrong and that the exact opposite is what is true, just based off our small sample size of 3 sponges. I am looking forward to finishing this project, as the process is both very fun and very exciting to watch. I am also looking forward to just getting back into the water, as I have really enjoyed the past two days in the water.                                                                    

  • Ervin Knezek

    Fascinating findings – i would have hypothesized the same thing. I am curious about the reasons and the implications for that.