1080

Understanding rates of reinvasion is critical for determining what drives ship rat population recovery following large-scale control operations. We radio-tracked 23 adult ship rats on the edge of a forested area where rats had been suppressed by aerial compound 1080 in the Hollyford Valley, Fiordland. Eleven individuals died within two months of collaring and two individuals were never detected again, leaving us with data from 10 rats.

A resetting toxin device (the “Spitfire”) has been designed that delivers a toxic paste to a rat’s ventral surface when it passes through a tunnel. The rat grooms off the paste and ingests the toxin. The system was assessed in cage trials and one field trial. The purpose of the cage trials was to investigate whether a range of toxins can be delivered by the Spitfire to rats (Rattus rattus and R. norvegicus), namely 0.55% sodium fluoroacetate (1080), 0.2% brodifacoum, 15% cholecalciferol, and 12.5% zinc phosphide.