Research Associate

email: snwyatt@uvic.ca lab phone: 250-472-5427 Shea’s website

Current Research Project

Silicon utilization and productivity of sea ice phytoplankton and diatoms in high-latitude marine ecosystems

My current research is driven by three guiding questions: 1) How productive are phytoplankton within and below sea ice? 2) How much ice algae productivity can be attributed to diatoms? 3) Is diatom productivity nutrient limited prior to sea ice breakup?

PhD Research Project

Nutrient Physiology of Siliceous Phytoplankton Under Warming and Acidification in Arctic and Subtropical Oceans

Rising atmospheric carbon dioxide levels are increasing the acidity (ocean acidification, OA) and temperature of global oceans, especially at high latitudes. Of particular importance within high-latitude marine ecosystems are diatoms, a group of silica-walled phytoplankton that play a significant role in taking up carbon dioxide, producing oxygen, supporting food webs, and regulating nutrient cycles. These cycles are highly connected and are important in determining the nutritional value of phytoplankton at the base of the food web and the ability of the ocean to absorb, export, and sequester carbon from the atmosphere. My PhD research investigated the response of diatom physiology to changing temperatures and OA in two distinct ecosystems, the Pacific Arctic Region and the Sargasso Sea. The response of diatoms to ocean acidification was also investigated through laboratory experiments with diatom mono-cultures. This research provided an important step forward in determining the impact of climate change on siliceous phytoplankton, particularly diatoms, and improved our understanding of how diatoms interact with marine cycles of Si, C, and N across cold and warm marine ecosystems. 

Other Research and Teaching Interests

• Physiological responses of phytoplankton to anthropogenic changes
• Dissolved nutrient and particle stoichiometry within Subarctic and Arctic phytoplankton assemblages
• Role of diatoms in the biogeochemical silicon cycle
• Carbon and nitrogen cycling through phytoplankton assemblages
• Use of case studies and “flipped” classrooms in science education
• Incorporation of meaningful formative assessment practices into daily learning routines
• Inquiry and project-based learning to create student-led learning experiences
• Increasing student advocacy and engagement with climate science

Education

2017 – 2024, Ph.D Biology, University of Victoria
2014 – B.Ed., UBC West Kootenay Teacher Education Program
2010 – B.Sc. Honours with Distinction, UVic Biology

Publications, Peer Reviewed

Richardson C, Peucker-Ehrenbrink B, Wyatt S, Bourbonnais A, Hatje V, Frey C, Sanders T, Varela D, Paytan A. (2024). Effects of climate change on river and groundwater nutrient inputs to the coastal ocean. Nature Communications Earth & Environment, submitted October 13, 2024.

Wyatt S.N., B.J. McNabb, and D.E. Varela. (2024). Morphological and physiological responses of the cosmopolitan marine diatom Thalassiosira rotula to acidification. Diatom Research, 1–14. https://doi.org/10.1080/0269249X.2024.2369049.

Kafrissen, S.M., K.E. Giesbrecht, B.J. McNabb, J.E. Long, C. Martin, S.N. Wyatt, M.G. Lagunas and D.E. Varela. 2022. An 8-year record of phytoplankton productivity and nutrient distributions from surface waters of Saanich Inlet. Sci Data, 9, 377. https://doi.org/10.1038/s41597-022-01434-y.

Wan Z, Azam M, Wyatt S, Ramsay K, Korner J, Elvira K, Padmawar R, Varela D, Hore D. (2021). Algae adhesion onto silicone is sensitive to environment-induced surface restructuring. Langmuir 31: 9597-9604, DOI:10.1021/acs.langmuir.1c01493

Wan Z, MacVicar B, Wyatt S, Varela D, Padmawar R, and Hore D. (2021). An automated image analysis platform for the study of weakly-adhered cells. Biofouling, DOI:10.1080/08927014.2021.1917555

Crawford D, Cefarelli A, Wrohan I, Wyatt S, Varela D. (2018). Spatial patterns in abundance, taxonomic composition and carbon biomass of nano- and microphytoplankton in Subarctic and Arctic seas. Progress in Oceanography. 162: 132-159.

Crawford D, Wyatt S, Wrohan I, Cefarelli A, Giesbrecht K, Kelly B, Varela D. (2015). Low particulate carbon to nitrogen ratios in surface waters of the Beaufort Sea and Canada Basin in the Arctic Ocean. Global Biogeochemical Cycles. 29(12): 2021–2033.

Wyatt S, Crawford D, Wrohan I, Varela D. (2013). Distribution and composition of suspended biogenic particles in surface waters across Subarctic and Arctic Seas. Journal of Geophysical Research: Oceans. 118(12): 6867–6880.

Varela D, Crawford D, Wrohan I, Wyatt S, Carmack E. (2013). Pelagic primary productivity and upper ocean nutrient dynamics across Subarctic and Arctic Seas. Journal of Geophysical Research: Oceans. 118(12): 7132–7152.

Other Publications

Wyatt S, Sullivan-Watts B, Watts D R, Sacks L. (2022). Facilitating climate change action in the ocean sciences using the interactive computer model En-ROADS. Limnology and Oceanography Bulletin. 3: 92-94. DOI:10.1002/lob.10504

Gilbert, B K. (2019). One of Us: A Biologist’s Walk Among Bears. Kaylene Johnson-Sullivan (Ed), Shea Wyatt (Photographer). Friesen Press. 

Wyatt S. (2010). A Pan-Arctic Perspective on the Contribution of Siliceous Phytoplankton to Autotrophic Biomass in Canada’s Oceans. University of Victoria. B.Sc. Honours Thesis.

Presentations and Posters

Wyatt S, Grundle D and Varela D. (2024). Shifting biogeochemical roles of different sized siliceous phytoplankton to primary production during the onset of fall conditions in the Sargasso Sea. Ocean Sciences Meeting 2024, New Orleans, LA. Feb 23, 2024. (oral)

Wyatt S, Giesbrecht K, and Varela D. (2022). Coupling of silicon, carbon, and nitrogen during uptake by summer phytoplankton assemblages in the Pacific Arctic Region from 2006 to 2021. Ocean Sciences Meeting 2022, Honolulu, HI. March 1, 2022. (online oral)

Wyatt S, McNabb B, and Varela D. (2020). Resilience of a Cosmopolitan Diatom to Induced Ocean Acidification Based on C, N, Si and Chlorophyll-a Stoichiometric Ratios, Nutrient Uptake Rates, and Morphology. Ocean Science Meeting 2020, San Diego, CA. February 2020. (poster)

Varela D, and Wyatt S. (2019). Marine pelagic primary productivity and nutrient dynamics in the Canadian and Alaskan Arctic: Over a decade of studies under the umbrella of the Canada’s Three Oceans, Distributed Biological Observatory, and GEOTRACES programmes. Synoptic Arctic Survey Planning Workshop, Woods Hole Oceanographic Institution, MA. May 15, 2019. (oral)

Wyatt S, Varela D, and Grundle D. (2019). Ocean acidification effects on siliceous phytoplankton from the Subarctic Northeast Pacific and Subtropical North Atlantic Oceans. ASLO 2019, San Juan, Puerto Rico. February 26, 2019. (oral)

Wyatt S(2018). Effects of ocean acidification and allelopathic toxins on biogenic silica precipitation in diatom assemblages in the northeast Pacific Ocean. Line P Meeting, Sidney, BC. March 20, 2018. (oral)

Wyatt S, Wrohan I, and Varela D. (2010). Contribution of siliceous plankton to autotrophic biomass and primary productivity in arctic and subarctic surface waters. Ocean Sciences Meeting ASLO/AGU, Portland, United States. February 22 – 26, 2010. (oral)

Institutional Presentations and Posters

Wyatt S, and Varela D. (2024). Unraveling the role of siliceous phytoplankton in nitrate utilization and productivity during a Sargasso Sea bloom. University of Victoria Biology Graduate Student Symposium, Victoria, April 9-10, 2024. (oral)

Wyatt S, and Varela D. (2023). Do Arctic diatoms tolerate increasingly acidic conditions during growth? University of Victoria Biology Graduate Student Symposium, Victoria, April 11-12, 2023. (oral)

Wyatt S, Giesbrecht K, and Varela D. (2022). Feeling the heat: is diatom productivity in the Pacific Arctic responding to long-term warming? University of Victoria Biology Graduate Student Symposium, Victoria, April 8, 2022.

Wyatt S, Grundle D, and Varela D. (2020). Trends in productivity and nutrient uptake by siliceous phytoplankton across a subtropical marine ecosystem. University of Victoria Biology Graduate Student Symposium, Victoria, November 9, 2020.

Wyatt S, Varela D, and Grundle D. (2019). Ocean acidification effects on the elemental ratios and nutrient uptake rates of siliceous phytoplankton from the Subarctic Northeast Pacific and Subtropical North Atlantic Oceans. University of Victoria Biology Symposium, Victoria, November 14, 2019.

Wyatt S, Varela D, and Grundle D. (2018). Particulate chlorophyll biomass at the Bermuda-Atlantic Time-series Study. BIOS Research Symposium, Bermuda. November 23, 2018.

Wyatt S, and Varela D. (2018). Ocean acidification impacts on primary producers from productive and oligotrophic oceans. University of Victoria Biology Symposium, Victoria, November 13, 2018.

Wyatt S, Varela D, and Grundle D. (2018). Methods to assess ocean acidification impacts on primary producers from productive and oligotrophic oceans. BIOS Research Symposium, Bermuda. November 2, 2018. (poster)

Workshops & Seminars

Wyatt S (2024). Silicon Superstars: Diatoms Under Warming and Acidification in Arctic and Subtropical Oceans. PhD Exit Seminar, Department of Biology, University of Victoria, BC. November 8, 2024.

Wyatt S, and Simonson, E. (2024). En-ROADs Climate Action Simulation. Water is Life Conference, Oak Bay High School, BC. July 5, 2024.

Wyatt S, and Sacks L. (2023). Working Together to Create a Safe Climate Future for All. ISABC Environmental Student Conference, University of British Columbia, BC. February 24, 2023.

Wyatt S, and Sacks L. (2022). En-ROADs Climate Workshop, Ivey Academy at the Ivey School of Business, London, ON. April 21, 2022. (online)

Wyatt S, Sullivan-Watts B, Watts D R, and Sacks L. (2022). Exploring climate change solutions for a sustainable future – a workshop and discussion centered around using a powerful interactive climate model in classrooms, the workplace, and beyond. Workshop Facilitator. Ocean Sciences Meeting 2022, Honolulu, HI. February 25, 2022. (online)

Wyatt S, and Varela D. (2020). Teaching and Learning during the Climate Crisis – Promoting Positive Thinking and Meaningful Action. Workshop Facilitator. Ocean Science Meeting 2020, San Diego, CA. February 2020

Varela D, and Wyatt, S. (2019). Teaching and Mentoring in the Aquatic Sciences Under the Threat of Climate Change. Workshop Facilitator. ASLO 2019, San Juan, Puerto Rico, February 26, 2019