Development of a cyanide pig bait for monitoring

Project Leader: Dr Matt Gentle, Qld DEEDI

Aim: To reduce risk of disease transfer from invasive animals to livestock and humans.

Projects:  8.d.1

Project summary

This project contributes to management recommendations for endemic and exotic diseases of invasive animals.

This project with Connovation Pty Ltd and Qld Department of Primary Industries (within Department Environment and Economic Development and Innovation) aims to trial cyanide baits for suitability for use with pigs and/or foxes in the field. Cyanide baits may be useful in a disease outbreak, restricting dispersal of animals from the baiting site, and allowing a method of monitoring animals for disease.

Pen trials were done on feral pigs using a variety of bait packages and cyanide formulations (powder, paste and liquid). Although cyanide has been shown to kill anaesthetised pigs in less than 20 minutes, the results with pigs not anaesthetised indicated that, with current encapsulation technology and at ‘pig-size’ doses, it appears difficult to disguise the cues associated with cyanide, given its distinctive smell and taste. Given these difficulties, it has been decided to cease testing any further cyanide packages on feral pigs until these issues can be overcome. However, the results obtained with pigs will be written up for publishing early next year.

The project has since focussed on using cyanide baits with foxes. Early results indicated that when baits are consumed, foxes are highly susceptible to cyanide. However, the fieldwork so far has shown that despite free-feed baits being readily consumed, baits were largely rejected by foxes following the addition of cyanide. Observations indicate that the detectability, environmental stability, and desiccation/contamination of the paste from the surrounding soil reduced the palatability and effective delivery of cyanide to foxes. Odour cues were surmised to be largely responsible for foxes detecting and rejecting cyanide baits.

Key achievements

  • Pen trials with pigs and foxes conducted to trial several bait-cyanide combinations.

Key deliverables

  • Further refinements will be made in the presentation, palatability and delivery of baits to help mask the taste or effect of the cyanide and improve the baiting technique. New formulations of cyanide and bait (including physically-encapsulated pastes) will be laboratory tested for cyanide gas emission, in simulated Australian field conditions of temperature and moisture. If the results show that odour cues are reduced, further field trials will be conducted with those formulations.
  • Final reports on applicability of cyanide for use in the field with pigs and foxes.

Project team

Dr Matt Gentle, Duncan MacMorran, Prof Charlie Eason.

Project partners

IA CRC, Queensland Department of Employment, Economic Development and Innovation, Connovation.

Further information

Aster D, Boot S and Gentle M (2008) Can we develop a cyanide bait for foxes? 2nd Queensland Pest Animal Symposium, Cairns, 19–22 October 2008 (unpublished).

Aster D, Boot S and Gentle M (2009) Development of cyanide bait for rapid disease sampling and surveillance of wild animals Supplementary Report to WEDPP (unpublished).

For further information, contact us.