Scripps Student Spotlight: Grace Cawley

PhD student studies zooplankton communities and their role in the California Current Ecosystem

Grace Cawley is a fourth-year PhD student from Salem, Mass., studying biological oceanography at Scripps Institution of Oceanography at UC San Diego. She received her bachelor’s and master’s degrees from the University of San Diego in environmental and ocean sciences with a concentration in marine ecology. At Scripps Oceanography, Cawley studies zooplankton ecology and is advised by oceanographer Moira Décima. Cawley received the David Cushing Prize by the Journal of Plankton Research for the Best Paper of an Early Career Scientist in 2021. In fall 2023, she also served as a delegate at COP28, the United Nations climate conference.


explorations now (en): Why did you choose to attend Scripps?

Grace Cawley in the CTD rosette setting up an underwater vision profiler
Cawley in the CTD rosette setting up an underwater vision profiler.

Grace Cawley (GC): When I started applying to PhD programs, my advisor at the time emphasized the importance of choosing a lab and an advisor over just choosing a school. She told me that life in graduate school is dependent on the relationships you form and the research you do. I took this to heart and sought out potential advisors who were doing interesting research, but I understood that graduate school is hard and that you are a human being before you are a researcher. I had previous experience working with my current PhD advisor, Moira Décima, and respected her as a person and a scientist. The community and opportunities that Scripps provided were an amazing addition to what has turned out to be an incredible opportunity that involves studying cool critters and working with amazing people! I chose Scripps because I found an advisor who took me from where I was as a student and is helping me find who I will be as an independent thinker and researcher. I can’t deny that seeing the ocean from my office, or the fact that I wouldn’t have to leave San Diego, didn’t sway my decision. But choosing a school based on an advisor and lab is something I stand by. Scripps is an amazing place with equally amazing people, and it’s pretty epic that I get to learn here! 


en: What are you researching at Scripps?

GC: I study zooplankton, ‘zoo’ means animals, and ‘plankton’ comes from the Greek word for ‘drifter’ or ‘wanderer.’ They are little animals that are at the will of the currents and are found in every water body from the ocean to small puddles in the leaves of trees in the rainforest. Zooplankton and phytoplankton make up the base of the food chain, and they play a large role in taking carbon from our atmosphere and repackaging it so that it can sink into the deep ocean. One organism that I research is called a pyrosome, a tubular pink jelly-like stick that is made up of hundreds to thousands of feeding and pooping organisms called zooids. I study many aspects of pyrosomes from what they eat, to where they live, and to what their presence means for an ecosystem. With this lens, I also look at zooplankton communities and see how the influence of pyrosomes and other climate-driven changes have shifted the community composition and what this means for other animals that live and feed in the California Current Ecosystem


en: How did you become interested in science and your field of study?

GC: Growing up I would build these puddles called “minnow hotels.” On a few occasions, I would find a lobster in the “minnow hotel,” and quickly our guest population dwindled. I remember wondering if there were holes, but then I realized that the lobsters were feasting. This was my first interaction with trophic ecology — the study of the feeding relationships of organisms. 

When I went to college, I began studying psychology, but I was assigned to a class about earth systems. I fell in love with rocks and water and decided to major in environmental and ocean sciences and thus began to dive into research in that field. I joined a research lab where I saw a small crustacean called a copepod poop under a microscope. From that moment I was hooked! Zooplankton are this magical group of animals that come in many shapes and sizes and have the capacity for big change. Their role in the food chain is astounding, and I will never stop being amazed by what a small animal can do. 

Grace Cawley deploying a net to catch zooplankton in the California Current aboard the R/V Sally Ride.
Cawley deploying a net to catch zooplankton in the California Current aboard the R/V Sally Ride.


en: What’s life like as a Scripps student? Describe a typical day.

GC: The thing I like most about being a Scripps student is that there is no typical day. Some days I’m at my computer writing, coding, or sorting through images and data. Other days I’m in the lab processing samples and prepping them to send out for analysis. There are times I’m at a microscope looking at small structures that define a species from one another. Other times I might be packing for our next seagoing adventure. I also enjoy the days when I work with undergraduates and high school students. Additionally, some days are nights because anytime I’m out at sea I find myself awake through the night, which is the best time for zooplankton hunting. Plus, there is nothing like tea and toast at four in the morning! 


en: What’s the most exciting thing about your work (in the field or in the lab)?

GC: I love going to sea. As a seagoing oceanographer, I find myself on large research vessels a few times a year going out to the zooplankton and studying them at the source. I’ve been on boats for as short as two hours to as long as 56 days. From doing regular net sampling, to live incubations on organisms, or looking at organisms under a microscope to count how many fecal pellets they produce, a day at sea is bustling. To finish it all off, you get rocked to sleep by the boat. It’s a true dream for me, and I am grateful every day that I get these opportunities! 


en: Are there any role models or mentors who have helped you along the way?

GC: I am so lucky to have many role models and mentors who have helped me along the way. Beth O’Shea, an environmental and ocean sciences professor at the University of San Diego (USD), showed me how cool rocks were and convinced me to switch to the environmental science major. She also earned the title of "life advisor" throughout my time as an undergraduate student and afterward. Jenny Prairie, a Scripps Oceanography alumna and current environmental and ocean sciences professor at USD, graciously invited me into her lab and taught me the ins and outs of research. My PhD advisor Moira Décima taught me everything I know about zooplankton and has been an active mentor since I was an undergraduate student. Years later I’m grateful for her mentorship and continued support in the journey of pursuing a PhD. All my labmates and friends have been amazing mentors and role models as well. Of course, my original role models and biggest fans are my parents. I really wouldn’t be where I am today without them!


en: What are some of the challenges you face as a student?

Grace Cawley presenting on zooplankton at the COP28 climate conference in Dubai.
Cawley presenting on zooplankton at the COP28 climate conference in Dubai.

GC: When you work in a collaborative environment, you interact with people from all walks of life. It’s amazing to learn from all these wonderful people, and I have learned that everyone has different communication styles and expectations. Learning to balance this and be flexible has been an interesting, yet beneficial challenge I have learned as a student! This adaptability also extends to challenges presented by data collection. In my work, I don’t always find the organism I’m looking to study, but that doesn’t mean that interesting questions and cool discoveries can’t be found. I just have to figure out how to look outside of the box.  


en: What are your plans post-Scripps?

GC: I have been pleasantly surprised by my path in science, and I look forward to seeing what will come next. I would love to continue researching zooplankton and work to push the plankton agenda helping to meld the world of zooplankton ecology with climate policy!


You can find Cawley on X @planktongrace and the Décima Lab on Instagram @decima.lab.

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