Postdoctoral Fellows

More profiles coming soon! 

Tim Bartley


I am a food web ecologist studying the causes and consequences of food web reorganization with global environmental change.

Currently, I am postdoctoral fellow at the University or Toronto Mississauga and the University of Guelph. I am integrating a range of empirical data, primarily from the Great Lakes and other aquatic ecosystems, to document how the organisms’ responses to global environmental change are ‘rewiring’ food webs. I am also developing theoretical models to explore how this food web rewiring impacts stability.

During my PhD, I examined the response of the whole lake food webs across the natural climate gradient in Ontario, Canada. By combining dietary data from both stable isotope analysis and molecular gut content analysis and inferring behaviour from catch-per-unit-effort data, I showed that whole fish communities in boreal shield lakes respond to increased temperature, producing flexible food web structure driven by rapid behavioral and feeding responses. These predictable responses of entire thermal guilds level to temperature imply a major reorganization of lake food webs with climate change.

Twitter: @TimothyJBartley


Gustavo Betini

Gustavo Betini, Postdoctoral Fellow

My research program aims to understand how ecological and evolutionary processes interact with each other to facilitate or inhibit adaptation in rapidly changing environments. Organisms have evolved a number of strategies to survive and reproduce in heterogeneous environments, but it is not clear whether a) these strategies will inhibit or facilitate rapid adaptation to fast environmental variation that is beyond the point of past selection and b) how rapid adaptation influences species interactions, demography and extinction probabilities. I approach these problems with an integrated framework that includes the development of new protocols in controlled laboratory settings, field research and mathematical modelling. This allows me to gather detailed data at the individual and population levels and combine physiological, ecological and evolutionary information to understand the drivers of fitness in changing environments.

Kevin Cazelles


I am a post-doctoral fellow at McCann Lab with a wide range of interests in ecology, from theoretical network ecology to very applied restoration ecology. I regard myself as a theoretician/data scientist motivated by a strong desire to apply the results of abstract investigations to tangible challenges such as the impact of land-use change on ecological networks.

ResearchGate profile:

Vasco Elbrecht


I am a PostDoc in the Steinke lab developing and optimizing methods to assess species biodiversity using DNA based methods. These focus currently on bulk invertebrate samples metabarcoding, but I am also involved in genome skimming, probe capture, and mitogenomics approaches around the globe. The strength of my research lies in tackling bioinformatics as well as laboratory problems and thorough protocol evaluations. I am also a strong believer in openly sharing and communicating your science, and thus am active on Twitter (@VascoElbrecht) and PrePrints.

Ellen Esch

Ellen Esch, Postdoctoral Fellow

Broadly, I investigate processes shaping ecosystem function, and how ecological processes respond to global environmental change. My current projects with BiRN center around the global challenge of feeding a growing world population while minimizing negative environmental externalities. Agricultural technologies have raised global crop yields over the past several centuries, yet increasing environmental variability associated with climate change can have large consequences for crop productivity. In collaboration with ALUS Canada, my current projects ask how farming management practices can influence productivity in variable climates.


Gabriel Gellner


I study the structure and functions of food webs to better understand our environment and biological complexity. Topics include theoretical ecology, population biology and how biodiversity affects ecological systems. As well, I’m interested in where the ideas and methods of theoretical ecology and ecoinformatics come from, and how they are applied. 

I've been a postdoc with Kevin McCann since September 2018. 


Matthew Guzzo


I joined the McCann lab as a post-doctoral fellow in May 2018. My research uses field- and lab-based approaches to understand how behaviour and physiology interact to shape the responses of species and their ecosystems to environmental change, with a focus on freshwater fish.

I previously completed my PhD at the University of Manitoba with Dr. Paul Blanchfield and my MSc with Dr. Aaron Fisk and Dr. Douglas Haffner at the University of Windsor.

Marjorie Sorensen

Marjorie Sorensen, postdocotoral fellow

I study the factors that influence individual success with the long term goal of more accurately predicting the population dynamics of species, especially in response to environmental change. Much of my work integrates field observations with laboratory analyses (stable isotopes, plasma metabolites, stress hormone, intensity of malaria infection) to estimate physiological condition and past events experienced by individuals.

At the University of Guelph, I will examine the effects of climate change on the population dynamics of Gray Jays (Perisoreus canadensis) in Algonquin Park. Evidence suggests that warming winter temperatures negatively affect Gray Jays by spoiling cached food that is meant to sustain them over the winter months. I will be working to disentangle the effects of temperature and major thaw events on cached food quality and long-term population trends in Gray Jays.

Rob Young

Rob Young, Post-doctoral researcher

I am a postdoctoral researcher and project manager in the Hanner lab and I am involved in numerous projects funded by the Canadian Food Inspection Agency in cooperation with the animal health, plant health, and operations branches. We work with different government and academic protocols to investigate biological targets of regulatory interest toward food protection and sustainability. One challenge of this work is to connect government research and protocols with Canadian interests through efforts to better access and share agricultural research data with industry, academic, and government representatives.

Our work will ultimately contribute to better tracking of animal and plant diseases and disease vectors. We have had numerous successes generating data sets, including DNA barcodes to further populate libraries, metabarcoding data from insect biosurveillance traps, metagenomics investigating plant pathogens, and qPCR data looking at targeted organisms. We have used these data to answer project-specific questions and to address the challenges related to data access. We also use these data to establish consistent formats and centralized storage through protocol development to provide a framework to increase data access and sharing.