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To manage brushtail possums (Trichosurus vulpecula) accurate estimates of abundance are essential Direct counts are not feasible for large populations and index techniques are normally employed A new index technique for estimating possum abundance is the WaxTagreg; They are potentially more effective than traps because they are small easier to use very lightweight and therefore higher numbers can be set out in the field Whilst a national monitoring protocol for WaxTagreg;s has been developed it is important to determine whether improvements can be made This study investigated firstly whether luminescentcoloured WaxTagreg;s were more attractive than the WaxTagreg; with a flour blaze and secondly whether raising the WaxTagreg;s 700 mm above the ground reduced detectability Possums significantly preferred the flour blaze over luminescence and raising WaxTagreg;s did not significantly reduce detectability Accordingly WaxTagreg;s could be raised up above grounddwelling nontarget species without reducing statistical precision

A new 1080 paste (PTP) was developed by Pest-Tech Ltd. and then evaluated in a series of comparative trials with Pestoff possum paste (POP). The research indicated that PTP was significantly more palatable to captive possums than POP following 57 h of exposure to ‘hot’ conditions (hot conditions were 30°C for 6 h followed by 18 h at 13°C on a 24 h cycle). Acceptance by bees was low with significantly less PTP than POP removed by forager bees over a 30 h period. In the field, the control efficacy of both pastes was high (89%-94% kill), with no significant differences between treatments. Based on these results, it is recommend that PTP is registered for possum control in New Zealand.

Two longlife baits (gel and polymer) were developed by PestTech Ltd and tested on captive ferrets The palatability of both baits was significantly enhanced using natural animal extracts with extract palatability ranked in order of decreasing consumption as rabbitchicken>harerat>fish Final bait formulations (with animal extracts) ranked in order of decreasing consumption were gelpolymer>Pestofftrade; ferret paste The response of ferrets to gel bait containing diphacinone was highly variable with males significantly more susceptible than females Accordingly large doses of diphacinone will be required to kill most ferrets in the field In conclusion both gel and polymer baits were superior to Pestofftrade; ferret paste and have good potential for ferret control

Aversions to sodium monofluoroacetate (1080) in cereal bait can persist in sub-lethally poisoned possum (Trichosurus vulpecula) populations. We investigated whether ‘shy’ possums could be controlled with an alternative toxicant (cholecalciferol or brodifacoum) and/or an alternative bait material (apple paste). Some shy possums (40%) were killed when exposed to 1080 in apple paste, whereas the alternative toxicants killed 70% when in cereal bait and 100% when in paste. These results demonstrate that 1080 bait shy possums can be controlled using alternative toxicants, provided the onset of poisoning symptoms is subacute or chronic. Effectiveness will be enhanced if the bait matrix is unfamiliar.