A Multi-dose Ejector for Control of Predator Pests

Summary

​Predator pest species pose a serious threat to Australian agriculture and its biodiversity. Control of these species in remote and regional Australia is difficult and problematic due to inaccessibility, a small labour force and the immense size of the area infested. Stage 1 of the MLA project B.AHE.0067 furthered previous research into the development of a chemical dosage dispenser or multi-dose ejector (MDE).

The MDE provided a target specific, multiple-dose toxin delivery system, capable of remaining field active over an extended period of time with minimal operational maintenance, through the use of new innovative technology.

Pen trials conducted during Stage 1 evaluated the components of the MDE successfully demonstrating its capabilities, highlighting also shortcomings that need additional investigation to enable a commercially viable and effective product. This phase has confirmed the formulation and delivery of an 'aerosol toxin formulation', and the fabrication of a 'polymer bait' with the durability to withstand multiple visitations by foxes, and the chemical stability to contain an attractant lure. The exclusion collar and pull force technologies provide a target-specific delivery technique which significantly reduces the risk of exposure to non-target species such as native fauna and working dogs. The aerosol toxin formulation has not been assessed on dogs and non-target species to date. Para-aminopropiophenone (PAPP), was selected as the toxin of choice for these trials due to initial restrictions placed on identified alternative toxins. With the MDE configuration, some sublethal results occurred using a standard on/off valve, however a metered dose valve would overcome this issue.

Based on the toxin PAPP the required lethal dose for dogs and foxes cannot be delivered with then-available metered-dose valves. Therefore, an alternative toxin that is effective at a lower dose rate could be used. Stage 2 of the pr​oject consolidated the MDE components, provided a clear direction forward in terms of the desired toxin for aerosol formulation using a metered-dose valve, to target both foxes and dogs. A potential range of polymer lures to target seasonal and individual attraction was developed.

Field trials was conducted to confirm the target specificity of the MDE for non-target species, demonstrate the efficacy of the MDE in a fox control program and examine its effectiveness for the control of wild dogs.

The MDE provided land managers with a cost-effective control technique, which enabled targeted control programs without restraints of seasonal accessibility or the continual replacement of baits. The MDE allowed for the establishment of long term sentinel sites to protect agricultural values and create buffer zones between private and public lands.​