The fate of dried meat baits laid for fox control: the effects of bait presentation on take by foxes and non-target species, and on caching by foxes

摘要

Non-toxic, dried meat baits (45 g) containing small radio-transmitters were laid on cleared sandplots in mixed farming and grain-growing areas in Western Australia. Baits were either buried, tethered by wire trace to a hidden peg, or simply laid untethered on the surface. Baits were exposed for 1 night only and new transects were established each day. Data were available on 1521 baits. Red foxes (Vulpes vulpes) visited 23% of plots and took baits from 64% of those visited. Unburied baits (both tethered and untethered) were taken significantly more frequently than the buried baits. Of all baits taken by foxes, 25% were cached. Foxes were more likely to cache buried baits than either tethered or untethered baits. Excluding baits taken to cubs, foxes cached baits 3–380 m (mean 87 m) from their original locations. Some baits were carried to cub dens up to 1.25 km away. The fate of 27 cached baits was monitored for varying periods. Of these baits, 59% were later eaten by foxes, most within 3 days. Non-target species took 3% of the baits on offer. Birds were the most common non-target animals to take baits, and in some cases dropped baits up to 400 m away. In terms of takes relative to visits, most takes by birds were of the untethered baits (88%, cf. 33% for tethered, 17% for buried baits). Compared with other baits, a significantly lower proportion of the untethered baits that were taken by birds was actually eaten. Baits cached by foxes and baits moved by birds represent a potential hazard to farm dogs and vulnerable fauna. Recommendations on bait presentation, distance restrictions, and likely risk to farm dogs and non-target species are discussed.