Field Stories: Chesapeake Bay, Virginia

By Madeline Eppley, Zea Segnitz, and Zoe Chapman

The Chesapeake Bay is one of the largest estuaries in the world, known for its historic, cultural, and ecological significance. Recently, we embarked on a fieldwork trip to the Virginia Institute of Marine Science to study one of the most iconic species of the Chesapeake Bay, the eastern oyster (C. virginica). Our research contributes insight towards understanding how oyster genetics impact survival and success under different environmental conditions.

​While there, our main goal was to monitor success of oysters growing in an ongoing experiment for the Lotterhos lab. This experiment involves raising juvenile eastern oysters with a variety of genetic backgrounds in two different sites within the Chesapeake Bay, the Lewisetta River and the York River. Our visit marked the 18-month point in the study, so we could really start to see substantial differences in survival and success across groups!  

So, what does day-to-day field work look like for marine biologists? As it turns out, there really isn't one standard day! We're going to walk you through each of our days as marine biologists working on oyster genetics in the Chesapeake Bay. While we are in the field, we do everything from boating to sampling sites, working in the field lab, collaborating with other researchers at VIMS, and spending lots of time outside! 

8:00 am: Our first task of the day is to drive two hours north to the Lewisetta River in Maryland, where one of our study sites is! We raise the oysters in mesh bags on racks at each site, which allows us to sample them twice per year for growth and mortality. 

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​10:00 am: Once we collected our samples, we return to the Aquaculture Genetics & Breeding Technology Center in the Acuff Center for Aquaculture at the Virginia Institute of Marine Science. Zea works on collecting samples for her own independent thesis! Madeline removes the predatory blue crabs from bags, where they have been eating the oysters. Unfortunately, this predation pressure can result in loss of study samples if the crabs are not routinely removed from the bags. 

​12:00 pm: We enjoy the beautiful November weather in Virginia by eating some lunch outside. We are close enough to the York River on the VIMS campus that we can see it from our field lab, where we have been working on collecting data this morning!

1:00 pm: Our afternoon starts by driving the tractor to the York River, where our second group of oyster bags are located. In our study, each of the two sites has a distinct environment. For example, the Lewisetta River is a low-salinity site, and the York River is a high-salinity site! 

When we arrive at the site, Zoe pulls up metal cages that are sitting on the bottom of the river bed using a large hook. These cages are long lines, meaning they're all attached to a rope underwater. They cages are heavy, so it takes effort to pull them up! 

Inside of each metal cage, there are three mesh bags that hold the oysters in the study. We make sure to collect the samples at low tide so that the water level is low enough for us to go out in our waders!

3:00 pm: Once we pull the oyster bags out of the water, we're under a time crunch to process data. Eastern oysters are filter feeders, meaning they need water to breathe, eat, and maintain basic function. They become stressed outside of the water, so we process them quickly and return them within 48 hours to the river. These oysters will continue to live over the next winter and we will check on them again in May 2025!

​5:00 pm: An important part of doing rigorous science is checking your work! At the end of our day, Madeline reviews all of the data that we collected. We check for errors and completeness. We also make an entry in our log, which is like a journal for our field data. This helps us to keep track of the environmental conditions at the site each day, hours worked, and any other important information.

Curious what else we do in a day at VIMS? Check out our video to see more clips and highlights from a day in the life as a marine biologist in the Chesapeake Bay! 

Undergraduate researchers Zea Segnitz 
(zeasegnitz.bsky.social) and Zoe Chapman 
​(zoechapman.bsky.social) are continuing on in the Lotterhos lab with independent projects slated for 2025/2026, stay tuned for the results of their work!