Ahead of summer, Dr John Llewelyn has used his expertise to predict the impact that climate change and bushfires will have on koala populations. He told us how a childhood love of the outdoors turned into a career, and why it’s taken him a while to adjust to SA winters.

What is your role here at Flinders?

I’m a Research Fellow in ecology, which means research is my focus but I also get a chance to do a little teaching. I’ve been here at Flinders since the end of 2018, having ‘migrated’ south from James Cook University, Townsville. Adelaide is great, but it’s taken a while to get used to the winters!

Tell us a little about your work.

I use machine learning and ecological network modelling to understand the dynamics of contemporary and ancient ecological communities. This involves identifying which species interact and applying this information to test how these interactions isolate or propagate disruptions in communities (ecological cascades) and trigger co-extinctions. I use this approach on diverse ecological systems, including Late Pleistocene communities that comprised of giant marsupials, reptiles and birds (megafauna); Devonian aquatic networks dominated by fish that were vastly different from those surviving today (including many armoured and jawless species, spiny sharks, and air-breathing lungfish); and contemporary communities suffering from the impacts of invasive predators such as cats and foxes. By taking species interactions into account, this research will help us understand past extinctions and guide measures to avoid future extinctions.

How did you get into this field?

I have always been into nature. As a little kid, I’d be out in the garden or the bush looking for critters (and to be honest, not much has changed since then). This connection to nature, coupled with my interest in understanding the world around me, drew me to biology. I did my Honours studying temperature sensitivity of nocturnal and diurnal snakes, then I did a PhD on native predators and their responses to cane toads, followed by a postdoc on climate adaptation in skinks. Now I’m applying network modelling to ancient and modern ecological communities—my career path has been fascinatingly (for me at least) convoluted.

What do you love most about your work?

I love collecting and analysing data to answer questions that have never been answered—it’s exciting and satisfying.

How do you like to spend your spare time?

Doing as much of the good stuff as possible: going to the beach, going bushwalking, spending quality time with my family, and checking out different places to eat and drink (there are so many great options in Adelaide and SA).

What’s your coffee order?  

My coffee order is chocolate, hot or iced, depending on the weather.