My name is Chelsea Fowler, and I’m a PhD student at the University of Maryland Center for Environmental Science. With the LOREX program, I’m headed to Southern Cross University in Australia to work with Prof Kirsten Benkendorff, conducting a study on two populations of Sydney rock oyster that may have different stress tolerances. While the oyster species I study at home, the eastern oyster, and the Sydney rock oyster I’ll study in Australia, are over 15,000 kilometers apart, they present two unique stress scenarios that both contribute to our body of knowledge on stress resiliency in oysters.
My home lab in Maryland
In Maryland, I study the resilience of juvenile eastern oysters to low salinity and hypoxia, two stressors projected to increase in the Chesapeake Bay due to climate change. We examine resilience through physical and molecular changes, including survival, growth rates, differential expression of stress biomarkers, transcriptomics, and epigenomics. We are also using these indicators to test stress priming as a method to enhance stress tolerance. Stress priming is an artificial stress enhancement technique in which a brief exposure to stress increases an animal's resilience to a subsequent exposure.
The National Marine Science Centre in Australia (Wikipedia)
In Australia, I’ll study the resilience of a sub-population of Sydney rock oyster that is believed to have acquired increased stress tolerance through natural selection. The Richmond River Estuary experiences poor water quality, low-oxygen blackwater events, and floods due to coastal development and hydrological modification. These conditions have severely reduced the Sydney rock oyster populations; however, while dismantling their lease, a local farmer noticed among the empty shells a darker-shelled oyster was still surviving (Ozfish Unlimited). Ozfish Unlimited, a non-profit organization monitoring the Richmond River also noticed these survivors during their surveys. Genetic analysis showed these distinct-looking oysters were still Sydney rock oysters, but more research is needed on this interesting sub-population.
The wild Sydney rock oyster and the Richmond River oyster, Ozfish
My project will evaluate the performance of this sub-population, the Richmond River oyster, and Sydney rock oysters from a different system to see if differences in resiliency can be observed under controlled conditions. We’ll use some of the methods I’ve grown accustomed to through my PhD work in Maryland, like differential gene expression using biomarkers for stress, and I will get to develop new skills working with proteins and stress enzyme assays.
As I get ready for this adventure, I’m intrigued by all of the new things this opportunity will bring with it. New experiences, ecosystems, colleagues, and critters. Participating in an international collaboration was a goal I had set for my graduate education, and I’m elated that this has become a reality. I’m looking forward to expanding my skills, incorporating new perspectives into how I approach scientific inquiry, and establishing comfort and home somewhere new.
