Research
My research mainly focuses on the ecology of marine predators (seals, seabirds and cetaceans) inhabiting sub-Antarctic and Antarctic ecosystems.
My present work, in collaboration with Andrew Lowther (Norwegian Polar Institute) and others, investigates foraging behaviour of krill-dependent Adélie, Gentoo and Chinstrap penguin populations in the Antarctic Peninsula region. An important goal of this research is to improve our understanding of predator-prey interactions at scales that are relevant for Ecosystem-Based Feedback Management of the Antarctic krill fishery. I started this work as a postdoctoral fellow at Nelson Mandela University, and continue with it in my current position as Research Fellow at University of Cape Town.
My background is in population ecology and the application of modern capture-recapture models. Between 2007 and 2020 I worked within the Marion Island Marine Mammal Programme of the University of Pretoria.
Penguins in Antarctica
Information on marine predator at-sea distributions and foraging behaviour is key to define priority areas for conservation.
We collect tracking data from penguins in the Antarctic Peninsula region to study how the habitat use, foraging behaviour and foraging success of krill-dependent penguins differ as a function of environmental conditions and prey availability, and how these may be influenced by commercial krill fishing operations.
Specifically, we deploy miniaturized Global Positioning System [GPS], accelerometer, time-depth recorders [TDR] and animal-borne cameras to obtain detailed information on the foraging behaviour of adult, breeding penguins.
Southern elephant seals
My postgraduate and postdoctoral research drew on three decades of empirical data collected at Marion Island to examine the various investments in growth, reproduction and survivorship that individual female elephant seals make.
As pups, seals exhibit substantial variation, or phenotypic plasticity, in weaning mass. This variation influences both the survival and reproductive trajectories of individuals in the long-term. The age at first breeding is a critical life history parameter, and indicates variation in individual quality. Together, phenotypic selection on weaning mass, and positive correlation between fitness components after first breeding suggests that individuals differ in their abilities to acquire and allocate resources.
For more information, visit the Marion Island Marine Mammal Programme's webpage.
Other Marine Predators
I have been fortunate to conduct collaborative research on a range of species, including killer whales, Southern Ocean fur seals and pack-ice seals, and flying seabirds, such as wandering albatross.