6/5-6/11

For my first week my mentors, Shelby and Emlyn eased me into the work I will be doing here. On Monday I went out on a tour of Sapelo, the island I am staying on, with several other interns and some students from the University of Georgia. I learned a lot of history about Sapelo and the people who used to live here as well as the community of people that still reside on the island. Later that day, I went out into our field site for the first time with Shelby. The site we are studying is in one of the island's marshes along Dean Creek. We scouted out various types of marsh edges that we will be using later in different predation experiments. 

On Tuesday, I met with Emlyn and we began the process of "shedding" the trematode parasites from the mud snails she had previously collected from the field site. It takes about two hours under an intense light for the parasites to shed from their hosts, so I used the downtime to review several papers on snail parasite studies. After the snails have finished shedding we micro-pipetted the cercaria, or the free-swimming larval form of the parasites, from the water in each snail's well and then put them onto a slide. We then began identifying the parasites based on physical characteristics we viewed under the microscope. After looking at the parasites, I began constructing snail cages that will be used out in the marsh to help determine how much benthic algae is being consumed by infected vs uninfected snails. 

On Wednesday, I joined a class being held on the island taught by Shelby and Emlyn. We started the day by learning about the shrimp disease Black gill. We then removed some of the gill filaments from the shrimp the class had caught the previous day. Next, we looked for the presence of any of the Black gill parasites under the microscope. Since July and August are the months when the disease is most prevalent not many of the shrimp were exhibiting signs of the disease. Later that day we learned about the different parasites present in Georgia that affect oysters. We then went out to an oyster reef and used the quadrat method to survey the oysters at different levels relative to the mud flat. After taking them back to the lab we identified what oysters were affected by which parasites. We also measured the lengths of the collected samples and quantified all the data with excel. 

I had a very long day this Thursday. I started out my morning by joining the class again, and listened to a lecture about the salt marshes we were going to go out in later that day. We then began making "squid pops" for our predation experiment we were going to be employing in the field. To do this we tied dried squares of squid to staked flags. We also tethered several mud crabs to stakes for another predation experiment. After lunch we went out to one of the salt marshes and placed our bait for the predation study. We left them for the tide to recede farther and completed a 100 meter transect of the marsh from one of the many streams. We collected data on the amount of burrows, snails, stalks of Spartina grass, and the heights of three random stalks in quadrats we placed every 10 meters. After collecting this data we went back to our predation study and recorded how many squid pops were eaten and how many tethered crabs were missing. After that I went back out into the field with Shelby near Dean Creek. We scouted out and recorded three groups of marsh edges we are going to use for future predation experiments. We recorded the coordinates with a GPS of 3 groups of different slump, slope, and escarpment marsh edges. In the following weeks we plan to kayak out to these locations and set up similar experiments to the ones we did today. 

On Friday, I started my morning by helping a PhD student make pull traps for one of his projects. Later that day I went beach seining with the class and another intern. We counted and weighed each species of organism we found. We saw a variety of species including lots of Cyprinidae, and even some squid. After that, I went out with the same PhD student on kayaks in one of the creeks to place slump blocks he had made for one of his projects. Later that night, I watched the sea life documentary, Surf's Up, with the class. 

On Sunday, I went out with the class and collected mud snails from different habitats along a mud flat. While out there we saw several blunt nosed sharks swimming near the oyster reef, which was really cool. After that, we took the snails back to the lab separated them by the sites they were found in, and began shedding them. After they had sat under the light for 2 hours we looked under the compound scope for any of the free swimming parasites. Typical snail parasite prevalence rates are around 5-10% so there weren't too many infected snails in the hundreds we were looking at. Once we found an infected snail we would identify its species of parasite and separate it from well plate. After collecting all our data we released the uninfected snails back into the marsh.