Central place foraging in an ectotherm and the long-term liability of selecting the "wrong" central place

Shelter provided by a fixed refuge like a burrow or nest has obvious advantages for central place foragers: the energy and time required to construct the refuge is expected to be offset by improvements in survival and reproduction. This assumes the refuge is positioned appropriately in the environment to access food and other resources, and that the environment itself remains stable over time. We investigated the long-term liability of refuge placement and adverse environmental change on an iconic central place forager, the Australian meat ant (Iridomyrmex purpureus). We measured the consequences of nest location on the thermal conditions experienced at the nest and how those conditions influenced the opportunity to forage and defend the nest from predation. These data were combined with direct field observations of foraging effort and changes in nest size obtained from over a decade of study. Getting the location of a nest wrong had a lasting impact on the growth of a nest and colonies were unable to compensate for subsequent time restrictions on activity through changes in behavior. Our data suggests that central place foragers relying on the long-term occupancy of a fixed refuge are especially vulnerable to environmental change. Unless these species compensate through changes in behavior or construct a new central refuge in an area outside of the zone of impact, the increasing frequency and severity of environmental change occurring with the climate crisis could increase the risk of local extinction.