Week 1: University of North Florida
On Monday we went to four different locations along the St Johns River. We were able to go out on the boat with Carissa King, a graduate student doing research dolphins in the river and how anthropogenic noise underwater affect their day to day life. In order to hear sound underwater Carissa showed us how to use a hydrophone, an instrument with a waterproof and very sensitive microphone on the end. Carissa is able to identify different fish in the river as well as man made noises with this device.The loudest and most frequent noise we were able to hear was snapping shrimp, which sounded like constant popcorn static. The next loudest noise we heard was the sound of boat engines. We were not able to hear any dolphins in our trip, however Carissa has heard many dolphins during her research. She has discovered that boat engines emit sounds at the same frequency that dolphins use when communicating, finding food, and mating. These noises are all causing a great disturbance to the dolphins that live in the river.
|Everyone gathered around Carissa waiting|
their turn to listen with the headphones.
Then we also analyzed water quality with Professor Kelly Smith. To analyze the quality of the water we used a couple different instruments. First we used a YSI meter to measure the amount of dissolved oxygen in the water, conductivity, salinity, and temperature. We also used a van dorn sampler to collect water sample from one meter down, then later analyzed the water in the lab. We also measured the turbidity in two ways, first we used a turbidity tube, where we collected water in tube and measured when we can see the bottom. We then compared that to the reading we got from a fluorometer which tests a sample water sample for turbidity. Then finally we discussed how all these factors affect the different ecosystems we saw that day.
|Walking along the coquina rocks looking|
in tide pools to see what we can find.
On Tuesday our objective was to observe different beaches and inlets. First we went to Marineland in St. Augustine to look at coquina rock and how it’s being used on sandy beaches. Coquina is a rock naturally made from shell fragments and calcium carbonate. These rocks are were placed on the beach to be used as natural jetties. The coquina provides an interesting habitat for species not usually found on sandy beaches like barnacles and sea anemones. Next we went to Summer Haven where they are dredging out the sand to let the water flow into the intracoastal waterway from the ocean. We then talked about how this will probably cause problems for the residents there because the new river will increase the rate of erosion around their beach front property. Next we looked at different types of inlets. First we went to the Matanzas inlet which is a consistently moving and shifting inlet that was formed naturally over time. It is usually characterized by having large sand bars in the middle of it. In an artificial inlet dredging is done so that ships can get threw. The problem with artificial inlets is that dredging must continuously be done to keep the inlet deep enough, which disturbs constantly disturbs the ecology of that area. Then we went to the GTM north beach to observe the high sand dunes and vegetation that grows on them.
|Collecting the data from our catch |
after our sein at during low tide.
On Wednesday our group was split into two smaller groups. My group began in the GTM NERR beach at low tide. During low tide the intertidal zone we had to walk on was very muddy and slippery which made taking water quality measurements an interesting experience. We also used a seine net to catch a bunch of organisms that we close to the shore. We were able to catch a large variety of fish including herring, silver side, and anchovy. We also caught some greater blue crab, and shrimp. Then the groups switched and we got to go on the shark boat. The goal was to catch some juvenile sharks swimming in the Tolomato river and take some take some measurements of them. In order to catch a shark we baited fifty circle hooks and set them on a line, each hook being three meters apart. Then we waited fifteen minutes to reel them all in. Unfortunately my group wasn't able to catch a shark, but we did catch a small catfish. However I enjoyed just seeing how this process is done.
|Jumping over a muddy creek to get to |
the first mangrove plot site.
On Thursday we went to the GTM NERR mangrove site. This was definitely the most difficult day by far. We began inland and moved toward the intracoastal waterway. The site was divided into 5 plots, starting we plot 5 we took measurement at each site. We looked at the percent cover of each species of plant. Then we took measurements of each mangrove tree within a one meter subplot. We split into smaller groups to analyze each plot. my group looked at plot 2 which was still too far inland to see the waterway. We saw some very big black mangroves as well as some baits and spartina. Even though walking through the mud and very tall grass was challenging seeing how exactly they analyze these large areas of mangroves and plants was very interesting.
On Friday we had a meeting to discuss what saw and learned over the week. We also listened to a lecture by Dr. Cliff Ross who gave us and introduction into coral reefs, which is was we will be learning about in The Keys. Overall this week was a great learning experience. This first week has already been so tiring, but so worth it. I am very excited to see what the rest of this course has in store.