Use of bait stations for possum and feral cat control

Abstract

Possum control in native forest is essential to reduce damage to native flora and fauna, so the development of more efficient control methods is a high priority. We investigated methods to improve control efficiency using toxic bait fed from bait stations. Results showed that by using the recommended bait station spacing grid of 150 m, and baits containing 0.15% 1080, a mean possum kill of 83% could be achieved after 3 weeks of prefeeding with non-toxic baits. With no prefeeding a mean kill of 68% was achieved. Prefeeding gave a 70% increase in the amount of 1080 baits being taken from the bait stations on the first night of baiting, but with no prefeeding 1080 baits were taken gradually over a 50 day baiting period. Fewer 1080 baits were taken from bait stations that fed cheaper prefeeds (i.e., maize and barley) than those that prefed non-toxic RS5 cereal pellets. No difference in bait consumption or possum kill was recorded from baits that were kept fresh by weekly replacement compared to baits that were left to become damp in the bait stations. Prefeeding before using Talon® baits reduced Talon® consumption by 37%, but possum kills were 14% less than with continuous baiting with Talon®. When Talon® was used regularly in small reserves, possum numbers were maintained at low levels throughout the year. Regular Talon® baiting proved to be more effective at maintaining possums at low levels than annual leg-hold trapping. When Talon® followed 1080 baiting, there was no further reduction in possum numbers but rat numbers were reduced a further 23%.