Recovery of possum populations after control occurs through immigration from adjacent areas and breeding of survivors and immigrants. If local elimination can be achieved, the population recovery will depend solely on immigration and therefore should be substantially slower, particularly in very large areas. Modelling predicts that local elimination of possums followed by ‘perimeter’ control (LEPC) is likely to be a more cost-effective control strategy than the current ‘knockdown-maintenance’ approach. Furthermore, immediate relief would be gained from all possum damage, while conventional maintenance control may, for example, take an estimated 4-8 years to eradicate bovine Tb from a residual population. Our ability to control possums has improved in the last three decades such that it now appears that local elimination is, technically, a realistic goal, and evidence will be presented that it is possibly already being achieved occasionally. Constraining factors include: unreliable monitoring at ultra-low densities, inappropriate selection and use of control options, lack of incentive under the present contraction system, initial cost, contracting capacity, and the future availability of 1080. However, these difficulties can be overcome, and should be if it is accepted that local elimination is sometimes a desirable and feasible goal.
|Author||Morgan, D., Nugent, G. and Warburton, B.|
|Secondary title||13th Australasian Vertebrate Pest Conference|
|Place published||Wellington, NZ|