BIOS Scientist and Board Member Supports Doctoral Student’s Research

Patricia Thibodeau, a doctoral student at the Virginia Institute of Marine Sciences, recently published a paper based on research conducted in collaboration with Amy Maas, an associate scientist at BIOS, and Deborah Steinberg, a professor at VIMS and a BIOS adjunct faculty member and trustee. The research, which is also part of her doctoral dissertation, focuses on tiny marine snails called pteropods.

Scientific conferences are an important, if not essential, part of a scientist’s life, both in academic and applied research. These gatherings, which often take place on an international scale, offer attendees the chance to learn about novel research, give presentations on their own research, and develop professional collaborations that can result in publications and funding opportunities.

This was certainly the case for BIOS associate scientist Amy Maas, a zooplankton ecologist, who attended the Zooplankton Production Symposium in Bergen, Norway in the spring of 2016, shortly after joining the BIOS faculty. A large part of Maas’ work involves studying tiny marine snails—called pteropods—to better understand how environmental changes, such as ocean acidification, impact their biology and distribution.

After a conference session, Maas was approached by Deborah Steinberg, a professor at the Virginia Institute of Marine Sciences (VIMS), and also a BIOS adjunct faculty member and trustee, who she’d met at the prior symposium in 2011. Steinberg, a zooplankton ecologist, introduced her to Patricia Thibodeau, a doctoral student at VIMS. Maas agreed to be on her doctoral committee and, together, the group brainstormed ideas for Thibodeau’s dissertation research.

Pteropods, also known as “sea butterflies,” are an important part of the marine food chain, serving as prey items for many species of fish. Thibodeau’s research looked at how pteropods in the Southern Ocean are impacted by rapidly warming sea temperatures and shifting availability of food.

“She was very interested in working with pteropods and having an experimental and climate change aspect to her research,” Maas said. “My work in the Ross Sea, Antarctica was some of the only experimental work done at that point on the effects of ocean acidification on pteropods in the Southern Ocean, so we spent some time thinking about best ways forward.”

They settled on a research topic, which eventually became the title of a paper recently published in the peer-reviewed Journal of Experimental Marine Biology and Ecology: “Effects of temperature and food concentration on pteropod metabolism along the Western Antarctic Peninsula.” Specifically, Thibodeau was looking at how pteropods in the Southern Ocean are impacted by rapidly warming sea temperatures and shifting availability of food. In the Southern Ocean, pteropods are an important part of the marine food chain, grazing on phytoplankton and serving as prey for many species of smaller fish, which, in turn, are eaten by other organisms such as larger fish, seabirds, and whales.

With the help of Maas and Steinberg, Thibodeau designed a set of experiments to conduct aboard the National Science Foundation (NSF)-operated research vessel Laurence M. Gould. During the course of three cruises from 2017-2019, Thibodeau used large nets to collect zooplankton down to depths of 400 feet (120 meters) within the Palmer Antarctica Long Term Ecological Research study area, an area located to the west of the Antarctic Peninsula from the coast to several hundred kilometers offshore.

Thibodeau (left, seen here with Steinberg) conducted her investigation over the course of three research cruises within the Palmer Antarctica Long Term Ecological Research study area, an area located to the west of the Antarctic Peninsula from the coast to several hundred kilometers offshore.

Once onboard, she isolated the four local species of pteropods from the samples and conducted a series of experiments to evaluate the animals’ metabolic responses to changes in carbon dioxide, temperature, and food (chlorophyll) availability. These experiments were carried out at sea to measure the organisms’ rates of oxygen consumption (respiration) and excretion.

“Identifying pteropod metabolic responses to environmental variability is key to determining the potential future effects of climate change on their physiology,” Thibodeau said. “Ultimately, this may affect their abundance, which is important to consider given their role in food webs and contribution to carbon and nutrient cycles in the Southern Ocean.”

The results of her research indicated that pteropods are more impacted—at least on short time scales—to changes in temperature, as opposed to food concentration or conditions of ocean acidification. This research also produced some of the first excretion rates for pteropods, which is important when determining the contribution of these organisms to carbon transport in the deep ocean.

For Maas, this collaboration was also one of the first times she served as an advisory committee member for a doctoral student. “I really appreciated Deb [Steinberg], who helped me understand how best to be of service in this role and support Tricia [Thibodeau] as she worked to defend her dissertation,” she said.