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Kat Stewart

Assistant professor

Dr. K.A. Stewart
+31 71 527 2727

Kat Stewart is ultimately interested in biodiversity and the policy tools to manage it: she researches (i) the drivers of diversification in changing environments among individuals, populations, and species, and (ii) develops cutting-edge molecular tools for practical applications in biodiversity monitoring and management.

More information about Kat Stewart

Professional experience

Kat graduated from Laurentian University (Canada) with a B.Sc. (Hons) in Wildlife Biology while simultaneously getting a degree in Environmental Science. Here, she conducted her thesis work in Mexico studying a newly discovered lizard species. Thereafter, she attained her M.Sc. in Evolutionary Ecology at the University of Western Ontario (Canada) studying local genetic adaptation and sexual selection in song birds. She then completing her Ph.D. in 2013 at Queen’s University (Canada) where she studied the drivers of hybridization among North American frogs using a suite of genetic tools and field/behavioural assays across Canada and the United States. After graduating, she immediately started as an Assistant Professor at Tongji University in Shanghai, China, using environmental DNA (eDNA) to augment and facilitate conservation management of the critically endangered aquatic mammal, Yangtze Finless Porpoise (Neophocaena asiaeorientalis ssp. asiaeorientalis).

Kat has lived, worked, and conduct research in a number of different locales spanning Canada, USA, Mexico, China, and The Netherlands. These opportunities have including rewarding positions as a Postdoctoral Research at the Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdaman, as an Assistant Professor in Shanghai, China at Tongji University (2014-2017), and as an Adjunct Professor (2016-present) in Environmental Studies at Queen’s University.

Kat’s passion for the natural world and conservation has seen her elected as the Vice-President (2009) and President (2010) of a local chapter for the Society for Conservation Biology, teach across various highschools, lead field expeditions for children to explore local wildlife, and intermittently work at the Toronto Zoo’s Conservation Department and Animal Hospital. She is also a strong advocate for diverse, equitable, and inclusive science, leading panel discussions on Women in Science and participating in a number of diversity groups across various universities. She currently acts as a Handling Editor for the journal Oikos, and as the Reviews Editor for the journal Evolutionary Ecology.

Kat started in CML in 2021 and is currently teaching in both the B.Sc. and M.Sc. programmes, including Environmental Biology, Water & Toxicity, and Global Challenges: Sustainability. 

Visit Kat Stewart’s personal website here.

Research topic

Global biodiversity is increasingly under threat from human activity, ultimately increasing both rates of extinction and invasion.. Cradled within environmental change, Kat examines how eco-evolutionary elements affect different species (e.g., endangered and invasive) and uses genetics to monitor and manage them. Thus, her research uses molecular tools to understand biodiversity; processes that drive or diminish rates of diversification in changing environments, and practical applications quantifying biodiversity and preventing its loss. She combines field, lab and quantitative approaches across a range of taxa (frogs, lizards, birds, mammals, invertebrates), to create a groundbreaking hypothesis-driven research programme.

Origins and maintenance of diversity under environmental change: One of the central challenges in evolutionary ecology is to the explain present-day distributions of diversity, and the nature and timing of the processes that shape them. An important facet of her research looks at how historical processes, such as fragmentation, shape range dynamics, contemporary geographic distributions, and opportunities for hybridization. She combines broad-scale fieldwork with genetic analyses, tests of mate preference, and in vitro hybridization experiments. She also seeks to understand gene-by-environmental interactions, looking at the effects of different eco-evolutionary processes on population persistence (evolutionary rescue) under changing environments, quantifying the genomic underpinnings of plastic responses. Using extensive field work, experimental evolution and Next-Generation Sequencing, this research seeks to answer questions that bridge dispersal ecology, population genomics and conservation management. This research will assist in predicting if and how species respond to environmental impacts (e.g. climate change), facilitating conservation prioritization and range-expansion corridors.

Novel molecular tools for applied questions: This research theme uses environmental DNA (eDNA; DNA shed by organisms into their environs) methods to infer distribution, conservation status, and surveillance of rare or hard-to-study taxa (e.g. endangered or invasive) via species-specific or metabarcoding assays. With Tongji University and Queen’s University, she integrated conservation genetics in policy and management, predominately focusing on conserving and restoring a critically endangered aquatic mammal, the Yangtze Finless Porpoise. Being among the first researchers to introduce eDNA tools to China, her work at Tongji University (Assistant Professor) successfully demonstrated proof-of-concept for practitioners in the field, including methodological cost comparisons, and critical assessment of the spatiotemporal use of a nature reserve. Her research team and Kat herself also quantified fish communities throughout the Yangtze River Delta, including the prey an endangered aquatic mammal which have historically been over-fished, resulting in advice for overharvesting remediation. Currently, eDNA is one of the fastest developing monitoring tools, driving rapid advancement across fields; it is a featured theme for global conservation horizon scans and is now widely used to assess the ecology and biodiversity integrity of European waterways under the European Water Framework Directive. At CML, she will continue to gain a comprehensive understanding of native-invasive species interactions using eDNA methodologies.

Assistant professor

  • Science
  • Centrum voor Milieuwetenschappen Leiden
  • CML/Environmental Biology

Work address

Van Steenis
Einsteinweg 2
2333 CC Leiden
Room number A3.02



  • No relevant ancillary activities
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