Livestock guardian dogs establish a landscape of fear for wild predators: implications for the role of guardian dogs in reducing human-wildlife conflict and supporting biodiversity conservation.
Abstract
Livestock guardian dogs (LGDs) are increasingly used to protect livestock from predators, but their effects on the distribution and behaviour of wild predators are mostly unknown. A key question is whether LGDs exclude predators from grazing land, or if predators continue to use areas with LGDs but modify their behaviour in ways that reduce impacts on livestock. We studied effects of LGDs (Maremma sheepdogs) on distribution and behaviour of red foxes Vulpes vulpes in north-eastern Victoria, Australia. We mapped the activity of LGDs across the study areas using GPS tracking and measured fox activity using remote cameras. We also measured risk-sensitive foraging in foxes to test if they reduced feeding time at sites regularly used by LGDs. Foxes occurred throughout areas occupied by LGDs, but their probability of detection was negatively related to the probability of LGD presence. Foxes extracted fewer food items from experimental food stations in proportion to the intensity of local activity of LGDs. This indicates that, though foxes overlapped with LGDs, they responded to risk of encountering LGDs by allocating less time to foraging. While LGDs do not necessarily exclude wild predators from areas used for livestock production, they can have strong effects on predator behaviour. Reduction in time allocated to foraging in areas regularly used by LGDs could lead to suppression of hunting behaviour and therefore a reduction in attacks on livestock. The flexible response of predators to LGDs should facilitate coexistence of wild predators with livestock farming, by allowing predators to continue to use areas occupied by livestock while still preventing attacks on those livestock. Our results therefore strengthen the case for use of LGDs in the conservation of predators threatened by conflict with farming. Suppression of hunting behaviour should also mean that prey species experience reduced rates of predation on farmland with LGDs. This effect could be valuable for conservation of threatened species of prey.