Suchergebnisse

Development of aversions, or learned 'bait-shyness', in frequently
poisoned possum (Trichosurus vulpecula) populations is
becoming increasingly detrimental to the efficacy of pest-control operations
in New Zealand. This experiment aimed to identify the effects of prefeeding, a
common management procedure, on the subsequent development of aversions in
possums. Wild possums (n = 96) were captured and
acclimatised, then allocated to one of three treatments groups that for seven
days received either (i) no prefeed, (ii) plain RS5 cereal baits, or (iii)
green-dyed and cinnamon-lured RS5 cereal baits. The possums were then offered
a standard green-dyed and cinnamon-lured RS5 bait that contained a sublethal
dose (0.4 mg kg-1) of the toxin sodium monofluoroacetate
(1080). The possums were tested for development of an aversion towards a toxic
RS5 1080 bait, a prefeed bait, and a prefeed bait containing an alternative
toxin, brodifacoum.
Most (96%) of the non-prefed possums became averse to the 1080 bait
after two exposures, compared with only 55% and 9% of the two
prefed groups. Similarly, 90% and 92% of the non-prefed possums
were averse to prefeed and brodifacoum baits, respectively, compared with
8% and 14% of the prefed possums. This suggests that pest
managers can reduce the risk of 'bait shyness' by prefeeding. A
further advantage of prefeeding is that if poison shyness develops, use of an
alternative toxin such as brodifacoum in the original bait base may still be
successful.