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RESEARCH ARTICLE
Contents Vol 37(4)

The effect of poisoned and notional vaccinated buffers on possum (Trichosurus vulpecula) movements: minimising the risk of bovine tuberculosis spread from forest to farmland

R. Pech A B , A. Byrom A , D. Anderson A , C. Thomson A and M. Coleman A
+ Author Affiliations
- Author Affiliations

A Landcare Research, PO Box 40, Lincoln 7640, New Zealand.

B Corresponding author. Email: pechr@landcareresearch.co.nz

Wildlife Research 37(4) 283-292 https://doi.org/10.1071/WR09161
Submitted: 20 November 2009  Accepted: 24 March 2010   Published: 28 June 2010

Abstract

Context. Vaccination of brushtail possums (Trichosurus vulpecula) has been proposed as a cost-effective alternative to lethal control for preventing potentially bovine tuberculosis (Tb)-infected possums from crossing forested buffer zones that abut farmland.

Aim. Evaluation of these two management option requires an estimation of the buffer width required to reduce the risk of disease spread to an acceptable level.

Methods. The movements of two groups of adult and subadult possums were monitored for up to 12 months in the Kaimanawa Range, North Island of New Zealand, using GPS technology. One group was in untreated forest immediately adjacent to a recently poisoned forest buffer, and the second group was 2 km further into untreated forest, which mimicked a vaccinated buffer with no reduction in possum abundance.

Key results. Close to the poisoned buffer, where the initial population density was 0.49–1.45 ha–1, adult possum home ranges averaged 10.2 ha in the summer immediately after control and 9.5 ha in the following winter. Two kilometres into the untreated forest, where the density was >3 ha–1, the corresponding values were only 3.5 ha and 2.8 ha. Over the first 6 months of monitoring, a ~350-m wide poisoned buffer would have contained 95% of movements by adult possums, as well as movements by most individuals, but a ~150-m wide vaccinated buffer would have been as effective. Equivalent results for the subsequent 6-month period were ~450 m and ~200 m for poisoned and vaccinated buffers, respectively. Movements by possums were not biased in the direction of the population ‘vacuum’ created by the poisoning operation. When subadult possums were included in the analysis, buffer widths of ~500–600 m for both poisoning and vaccination would be required to contain 95% of new den site locations.

Conclusions and implications. Detailed data on possum movements provide a means for agencies managing Tb to specify the width of a buffer, subject to an acceptable level of risk that it could be breached by a potentially infected possum. As well as depending on the width of a treated buffer, the final cost-effectiveness of vaccination compared with poisoning will depend on the relative cost of applying the two control techniques, and the frequency of application required either to prevent Tb from establishing (in the case of vaccination) or to suppress possum density (in the case of lethal control).


Acknowledgements

This project was contracted by the Animal Health Board (Project R-10699). Funding for GPS collars was provided by Landcare Research. The research was approved by the Landcare Research Animal Ethics Committee (AEC approval no. 07/09/03). Mandy Barron ran the computer simulations using the spatial model for possum population dynamics. Technical support was provided by C. Brausch, D. Clarke, K. Drew, S. Hough, D. Richards and J. Williamson. Hawke’s Bay Regional Council and Epro Ltd provided possum monitoring data and valuable assistance in selecting the study area. Thanks to various hunters for returning radio-collars from possums killed in this popular hunting area. Access was permitted by the Department of Conservation, and the Bay of Plenty District Health Board approved the use of toxins for retrieving collared possums at the end of the study. Thanks to Dan Tompkins, Phil Cowan and Graham Nugent for comments on the manuscript.


References

Aldwell, F. E. , Keen, D. L. , Parlane, N. A. , Skinner, M. A. , de Lisle, G. W. , and Buddle, B. M. (2003). Oral vaccination with Mycobacterium bovis BCG in a lipid formulation induces resistance to pulmonary tuberculosis in brushtail possums. Vaccine 22, 70–76.
| Crossref | GoogleScholarGoogle Scholar | CAS | PubMed | Animal Health Board (2005). National bovine tuberculosis pest management strategy. National Operation Plan: 1 July 2005–30 June 2013. Animal Health Board, Wellington.

Animal Health Board (2008). Annual Report for the year ending 30 June 2008. Animal Health Board, Wellington.

Barlow, N. D. (1991). Control of endemic bovine Tb in New Zealand possum populations: results from a simple model. Journal of Applied Ecology 28, 794–809.
| Crossref | GoogleScholarGoogle Scholar | Barlow N. D. (2000). Models for possum management. In ‘The Brushtail Possum. Biology, Impact and Management of an Introduced Marsupial’. (Ed. T. L. Montague.) pp. 208–219. (Manaaki Whenua Press: Lincoln, New Zealand.)

Bates D. , and Maechler M. (2009). lme4: Linear mixed-effects models using S4 classes. R package version 0.999375-32. Available at http://CRAN.R-project.org/package=lme4 [Verified November 2009].

Batschelet E. (1981). ‘Circular Statistics in Biology.’ (Academic Press: London.)

Brockie, R. E. , Ward, G. D. , and Cowan, P. E. (1997). Possums (Trichosurus vulpecula) on Hawkes Bay farmland: spatial distribution and population structure before and after a control operation. Journal of the Royal Society of New Zealand 27, 181–191.
Burnham K. P. , and Anderson D. R. (2002). ‘Model Selection and Inference.’ (Springer-Verlag: New York.)

Clinchy, M. , Krebs, C. J. , and Jarman, P. J. (2001). Dispersal sinks and handling effects: interpreting the role of immigration in common brushtail possum populations. Journal of Animal Ecology 70, 515–526.
| Crossref | GoogleScholarGoogle Scholar | Coleman J. , and Caley P. (2000). Possums as a reservoir of bovine Tb. In ‘The Brushtail Possum. Biology, Impact and Management of an Introduced Marsupial’. (Ed. T. L. Montague.) pp. 92–104. (Manaaki Whenua Press: Lincoln, New Zealand.)

Coleman J. , and Livingstone P. (2000). Fewer possums, less bovine Tb. In ‘The Brushtail Possum. Biology, Impact and Management of an Introduced Marsupial’. (Ed. T. L. Montague.) pp. 220–231. (Manaaki Whenua Press: Lincoln, New Zealand.)

Cowan P. , and Clout M. (2000). Possums on the move: activity patterns, home ranges, and dispersal. In ‘The Brushtail Possum. Biology, Impact and Management of an Introduced Marsupial’. (Ed. T. L. Montague.) pp. 24–34. (Manaaki Whenua Press: Lincoln, New Zealand.)

Cowan, P. E. , and Rhodes, D. S. (1993). Electric fences and poison buffers as barriers to movements and dispersal of brushtail possums (Trichosurus vulpecula) on farmland. Wildlife Research 20, 671–686.
| Crossref | GoogleScholarGoogle Scholar | Efford M. (2000). Possum density, population structure, and dynamics. In ‘The Brushtail Possum. Biology, Impact and Management of an Introduced Marsupial’. (Ed. T. L. Montague.) pp. 47–61. (Manaaki Whenua Press: Lincoln, New Zealand.)

Efford, M. , Warburton, B. , and Spencer, N. (2000). Home-range changes by brushtail possums in response to control. Wildlife Research 27, 117–127.
| Crossref | GoogleScholarGoogle Scholar | NPCA (2008). ‘Possum Population Monitoring Using the Trap-Catch Method.’ (National Possum Control Agencies: Wellington, New Zealand.)

Pfeiffer, D. U. , Hickling, G. J. , Morris, R. S. , Patterson, K. P. , Ryan, T. J. , and Crews, K. B. (1995). The epidemiology of Mycobacterium bovis infection in brushtail possums (Trichosurus vulpecula) in the Hauhungaroa Ranges, New Zealand. New Zealand Veterinary Journal 43, 272–280.
|  CAS | PubMed | R Development Core Team (2009). ‘R: A language and environment for statistical computing.’ (R Foundation for Statistical Computing: Vienna.) Available at http://www.R-project.org

Ramsey, D. , and Cowan, P. (2003). Mortality rate and movements of brushtail possums with clinical tuberculosis (Mycobacterium bovis) infection. New Zealand Veterinary Journal 51, 179–185.
|  CAS | PubMed | Rodgers A. R. , Carr A. P. , Smith L. , and Kie J. G. (2005). ‘HRT: Home Range Tools for ArcGIS.’ (Ontario Ministry of Natural Resources, Centre for Northern Forest Ecosystem Research: Thunder Bay, Canada.)

Rupprecht, C. E. , Hanlon, C. A. , and Slate, D. (2004). Oral vaccination of wildlife against rabies: opportunities and challenges in prevention and control. Developmental Biology 119, 173–184.
|  CAS | Speedy C. (2003). Hatepe Trial – comparison of ground and aerial Tb vector control methods. Epro Research Report, December 2003.

Tompkins, D. M. , Ramsey, D. , Cross, M. , Aldwell, F. E. , de Lisle, G. W. , and Buddle, B. (2009). Oral vaccination reduces the incidence of bovine tuberculosis in free-living wildlife species. Proceedings of the Royal Society of London B Biological Sciences 276, 2987–2995.
| Crossref | GoogleScholarGoogle Scholar | CAS | Venables W. N. , and Ripley B. D. (2002). ‘Modern Applied Statistics with S.’ 4th edn. (Springer: New York.)

Ward, G. D. (1985). The fate of young radiotagged common brushtail possums, Trichosurus vulpecula, in New Zealand lowland forest. Australian Wildlife Research 12, 145–150.
| Crossref | GoogleScholarGoogle Scholar |