Predation by feral pigs on Merino lambs at Nyngan, New South Wales

Abstract

The effects of feral pigs on the lambing performance of Merinos was studied at Nyngan, New South Wales. Ewes lambed in two paddocks; one with feral pigs and one with no pigs in autumn and spring in 1978 and 1979. Ewes were pregnancy tested before lambing, and after lambing, classified as dry, lactating or lambed-and-lost. Lambs were mustered weekly in three lambings. Pig movement in three lambings was controlled by electric fences. There were effects (P < 0.05) of feral pigs, years, seasons, and pigs x years on the percentage of ewes lactating, of those lambing. Feral pigs lowered the number of lambs per 100 ewes by 37.9 and 31.9 in autumn and spring 1978, respectively. In 1979 pig predation was an insignificant cause of lamb loss.