Hydrogel ant bait for all work was prepared by placing hydrogels in 30% sugar‐water solutions containing 0.006 mL L–1 fipronil [sourced from Termidor® (BASF, Florham Park, NJ, USA) containing 100 g L–1 fipronil] (i.e. a mixture of water:sugar:Termidor® of 350:150:0.003), and allowing 24 h for the solution to be absorbed. Sugar used was standard 1A sugar from the New Zealand Sugar Co. Ltd, Aukland, New Zealand), and the hydrogels were Water$ave Floragel® from Polymer Innovations Pty Ltd, Singleton, NSA, Australia). The bait was prepared 24 h before use in all instances.
The bait dispersal mechanism was a 300‐mm granular spreading disk, hereafter referred to as the spinner, spinning at 720 rpm which propelled the hydrogels out with centrifugal force as they flowed down from a holding container, in the same manner as any manual fertilizer spreader.
The bait dispersal mechanism was a 300‐mm granular spreading disk, hereafter referred to as the spinner, spinning at 720 rpm which propelled the hydrogels out with centrifugal force as they flowed down from a holding container, in the same manner as any manual fertilizer spreader.