The effectiveness of a large-scale baiting campaign and an evaluation of a buffer zone strategy for fox control

Abstract

The effectiveness of a baiting campaign against red foxes (Vulpes vulpes) was investigated in a rangeland area near Carnarvon, Western Australia. An area of 3180 km² was aerially baited with dried meat baits containing 3 mg 1080 poison (5 baits km^–2) in August 1995. All 45 radio-collared foxes monitored in the area were killed by baits. More than half the radio-collared foxes died within 3 days of baits being laid; the last surviving radio-collared fox died 44 days after baits were laid. The overall population reduction was estimated to be >95%. Further implications of this high level of bait uptake are discussed in relation to immunocontraceptive control of foxes, as well as for population reduction or vaccination of foxes to control rabies.

Reinvasion of the baited area occurred mainly in autumn, when juvenile foxes were dispersing. The relevance of this result is discussed in relation to developing more effective baiting strategies. As part of another experiment, outer sections of the baited area were periodically re-baited as a buffer zone to reduce immigration by foxes into the central baited area; the buffer baiting proved to be very effective in preventing recolonisation of the entire baited area.