The Acceptance of Dyed Grain by Feral Pigs and Birds. 3. Comparison of Intakes of Dyed and Undyed Grain by Feral Pigs and Birds in Pig-Proof Paddocks.

Abstract

In a 2-year study maize, wheat and sorghum grains, and a green and a blue dye were used. Of 57 bird species recorded in the study area only galahs and crested pigeons were observed eating grain. Neither feral pigs nor birds had differences in intake of undyed or dyed grain on average over the study; however, intake differences were highly variable as a result of interactions involving years, seasons, grains and times within seasons. Daily grain intake per pig averaged 2.33 kg and daily grain intake by all birds averaged 0.24 kg. Intakes by pigs and birds varied significantly with years, seasons, grains and times within seasons in complex interactions. The study suggests that poisoned grain baits for feral pig control may be dyed with little effect on intake by feral pigs, but that dyeing poisoned grain may not decrease its acceptance by some bird species.