Biological Invasions

, Volume 15, Issue 8, pp 1653–1663 | Cite as

Evaluating and predicting risk to a large reptile (Varanus varius) from feral cat baiting protocols

  • Tim S. JessopEmail author
  • Michael R. Kearney
  • Joslin L. Moore
  • Tim Lockwood
  • Michael Johnston
Original Paper


Control of introduced predators to mitigate biodiversity impacts is a pressing conservation challenge. Across Australia feral cats (Felis catus) are a major threat to terrestrial biodiversity. Currently feral cat control is hindered by the limited utility of existing predator baiting methods. Further proposed control methods include use of the novel poison para-aminopropiophenone (PAPP) which may present a hazard to some native animal populations. Here we used experimental and predictive approaches to evaluate feral cat bait take by a large native Australian predatory reptile the Lace monitor (Varanus varius). These lizards would be expected to readily detect, ingest and consume a lethal dose (depending on toxin) from surface-laid baits intended for feral cat control if a precautionary approach was not adopted when baiting. We modelled V. varius bait take using experimental and predictive biophysical modelling approaches to evaluate temporal effects of climate variables on V. varius activity and hence potential for bait removal. Finally we conducted a pre-PAPP baiting site occupancy assessment of V. varius within Wilson Promontory National Park (WPNP) to provide a basis for monitoring any longer term population effects of cat baiting. V. varius removed 7 % of deployed baits from 73 % of bait stations across another study area in Far Eastern Victoria. Daily bait removal was positively correlated with maximum temperature and solar radiation. Biophysical modelling for Far Eastern Victoria predicted that maximum temperatures <19.5 °C prevented V. varius activity and hence opportunity for bait removal. V. varius in WPNP was undetectable suggesting aerial baiting posed limited hazard to this species at this location. Depending how climate influences annual activity patterns and the specific poison, surface-laid baits could pose a significant mortality risk to V. varius. However, use of biophysical models to predict periods of V. varius inactivity may provide a novel means to reduce non-target bait take by this predator.


Introduced predators Poison baits Non-target risk Mechanistic niche models Varanid Lizards Varanus varius Felis catus Para-aminopropiophenone 



An Early Career Research Award from the University of Melbourne to TSJ. MRK was supported by an Australian Research Council grant DP110102813 facilitating analytical components of this research. The research was carried out under research permits 10005634 from the Department of Sustainability and Environment, Victoria, and Animal Experimental Ethics Committee approval DSE AEC10.15.A (Department of Sustainability and Environment, Victoria) and 0911328.2 (University of Melbourne). Julie Quinn and Dave Algar provided useful comments on earlier drafts of the manuscript.

Supplementary material

10530_2012_398_MOESM1_ESM.docx (2 mb)
Supplementary material 1 (DOCX 2027 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  • Tim S. Jessop
    • 1
    Email author
  • Michael R. Kearney
    • 1
  • Joslin L. Moore
    • 2
  • Tim Lockwood
    • 1
  • Michael Johnston
    • 3
  1. 1.Department of ZoologyUniversity of MelbourneParkvilleAustralia
  2. 2.Australian Research Centre for Urban Ecology, Royal Botanic Gardens, Melbourne, c/o School of BotanyUniversity of MelbourneVictoriaAustralia
  3. 3.Department of Sustainability and EnvironmentArthur Rylah InstituteHeidelbergAustralia

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