1. Rabbit Control Research Can learnings from possums be applied to rabbits? B. Warburton, G. Nugent, P. Fisher, J. Parkes, R. Clayton, G. Morriss

2. Outline Main research and operational aim What have we learnt from possums? Is there potential to apply this knowledge to rabbit control? Planned research projects

3. Current standard operational practice 2-3 kg/ha of 12g 1080 baits 170-250 baits/ha for ≤ 20 possums & rats/ha Why are we not using less? Research and Operational Aim: To reduce sowing rates and cost From Dave Morgan

4. What have we learnt? Prefeed…1 Cautious feedersGluttons Possum pen trials

5. What have we learnt? Prefeed…2 Prefeed significantly increases the kill achieved Results of field trial at Whirinaki (Nugent et al 2008)

6. 5 days before prefeeding 5 days during prefeeding What have we learnt? Prefeed…3 GPS location data from a possum before and during prefeed. Prefeed line

7. What have we learnt? Bait aversion 0%50%100% Rata Rd Cereal Te Tehi Cereal Rata Rd Carrot Te Tehi Carrot % of baits GonePart eatenUntouched After a carrot operationAfter a cereal operation

8. (b) After sowing 0 20 40 0.53.56.59.512.5 % (a) Before sowing 0 20 40 0.53.56.59.512.5 % What have we learnt? Bait fragmentation Bait weight class (g) Before sowing 0 10 20 30 0-12-34-56-78-910-1112-13>14 % After sowing 0 10 20 30 40 0-12-34-56-78-910-1112-13>14 % No 7 baitRS5 bait Bait weight class (g)

9. What have we learnt? Reducing the sowing rate…1 Sown at 3kg/ha ● ≤ 2g = sublethal ● > 2g

10. What have we learnt? Reducing the sowing rate…2 Sown at 0.25kg/ha

11. What have we learnt? Reducing the sowing rate…3 Sown at 0.25kg/ha 100m

12. Potential to apply similar approach to rabbits…1 Rabbit densities:  Common abundance index used is rabbits per spotlight kilometre (up to 300)  Moller et al. 1999. Density estimates within patches up to 50 rabbits/ha (mean 19/ha). Current bait sowing rates:  25 to 45kg/ha (up to 60kg/ha)  At 30kg/ha and 5g baits applying 6000 baits/ha! Toxic loadings registered:  Carrot = 0.02% (LD99 = c. 3mg/kg) – Need three 5-g baits  Cereal = 0.04 & 0.06% For carrot bait at 0.02% 1080 and 50 rabbits/ha need at most c. 150 baits (750g/ha).

13. Potential to apply similar approach to rabbits…2 From Batchelor (1982) 2007 ERMA 1080 reassessment: All carrot bait for aerial application to be screened at a mean weight of 6g Ground laying of bait does not have to be screened. So what is the bait size 1080 conc distribution of sown bait?

14. Potential to apply similar approach to rabbits…3 Secondary vs primary control Primary control (aerial 1080) needed after 8 years Secondary control (helicopter shooting, night shooting, spot poisoining) From Lough 2009 Can secondary control maintain the gains of RHD and remove the need for repeat primary control using 1080? – at what costs? How can conventional control and RHD be effectively integrated?

15. Planned Research…1 Project 1. A review paper: To re-assess the single dose LD100 for 1080 and pindone. Project 2. An analysis of bait size distributions and 1080 toxic loadings for cereal, screened carrot, and unscreened carrot before and after sowing. Project 3. Construct a probabilistic model of numbers of bait encounters needed to kill rabbits of different size and susceptibility – as done by Batchelor (1982) and Frampton et al. (1999). Project 4. An observational study of how rabbits react to carrot and cereal baits at first ever encounter, and test acceptance of a one-shot ‘perfect’ carrot bait with and without prefeeding.

16. Planned Research…2 Project 5. Home range use and effect of prefeed on foraging patterns (GPS) – implications for trickle sowing. Project 6. Rabbits, coprophagy, and pindone. Can pindone be used as a one-hit application? Project 7. Secondary control – extending the benefits of RHD – what is effective and at what cost? Project 8. Integrating RHD with conventional control – development of a DSS for end-users. Project 9. Developing a web-based bibliography of all published and unpublished rabbit research literature: - Jim Bell’s (MAF rabbit group) - Rabbit & Land Management Programme (special thanks to Don Ross for making MAF and RLMP material freely available)

17. From the late Jim Bell’s photo collection A typical scientist!!