An electrified watering trough that selectively excludes kangaroos.

It is generally agreed that the provision of artificial watering points has allowed populations of large kangaroos to increase in the arid and semi-arid rangelands. This study examines the effectiveness of a selective watering device, known as a 'Finlayson Trough', that is designed to exclude kangaroos but allow sheep to drink. The device is a low-lying electrified wire that surrounds a trough and is overstepped by sheep but contacted by a kangaroo's feet or tail. Of the 292 observed attempts at drinking by red kangaroos (Macropus rufis), 99% were unsuccessful. Most shocks were received through the feet. Of the 309 observed attempts at drinking by sheep, minor shocks to the legs were received in 17% of cases. These resulted in only short-term disruptions to drinking. Finlayson Troughs could be used humanely to facilitate commercial kangaroo harvesting by exploiting local concentrations of kangaroos around watering points; to control the distribution of kangaroos in sensitive regenerating areas; or, by gradual implementation, to allow kangaroos to adjust their behaviour to accommodate fewer artificial watering points.