Abstract
Animal movement sits at the crossroads of multiple ecological applications, and its study can provide valuable insights into a range of patterns and processes. Within the field of movement ecology, there is a growing demand for models that forge links between animal movements and other related ecological processes. Related to this is increased interest in how Adélie penguins (Pygoscelis adeliae) forage in response to different conditions, and how that variation impacts their chick-rearing behaviour. This research is critical, as Adélie penguins, particularly their foraging behaviour and population demography, have been identified as key priorities in the management of an internationally significant conservation zone (Ross Sea marine protected area [MPA]). The broad research goal of this thesis was to describe in better detail the foraging patterns of Adélie penguins, and then construct models that mechanistically link the foraging movements of breeding adults to the health of their chicks. Through tests of the field methodology, both adult foraging behaviour and the growth and survival of chicks were found to be impacted by the deployment of external, but not internal, tags on parents. Through state space models of movement, Adélie penguins were found to actively forage almost constantly while at sea, rather than seeking particular sites or habitats. Additionally, those models revealed that a range of covariates, including sex, fledgling success, and sea ice concentration were associated with the types of foraging exhibited. Through mechanistic modelling, variability in foraging behaviour had a demonstrable impact on the growth and survival of chicks, and more efficient foragers tended to have larger chicks with lower mortality rates. The model development process revealed several under-reported issues associated with the implementation of common modelling choices in animal movement research. In particular, the use of polar coordinates can generate discontinuities in their joint distributions if their dependency is not accounted for. Overall, this research contributed to understanding of Adélie penguin foraging behaviour, which is relevant for monitoring the effectiveness of the Ross Sea MPA. It also demonstrated how the movement of animals could be mechanistically linked to other ecological processes, highlighting the range of insights such approaches can offer. Overall, this research underscores the value of cross-disciplinary work and the potential to advance progress in multiple fields.