Trapping tunnel design incorporating behavioural preferences of stoats

Abstract

Stoats (Mustela erminea) are introduced pests in New Zealand, and there is an urgent need for effective trapping systems that kill the animal in a humane manner. A treadle trap was designed, the Dominus trap, that utilised an earlier‐proven humane killing system enhanced by the addition of a treadle plate trigger. This system enabled the trap to be classified as a Class A trap under the National Animal Welfare Advisory Committee (NAWAC) guidelines for animal kill traps, by successfully rendering 10/10 animals unconscious within 30 s. The Dominus trap mimics a tunnel, which by its very shape entices the animal to enter, but weighs only 600 g. Atrial at Flea Bay, on Banks Peninsula, used 35 Dominus traps placed alternately between 35 Fenn Mk VI traps set over 3150 trap nights (TN). The trial was conducted from March to May 2007 and was repeated for a further 7740 trap nights from January to March 2008, using 20 Dominus traps. The Dominus trap caught stoats consistently at the rate of 0.22 stoats/100 TN in both years, compared with 0 and 0.14/100 TN in Fenn traps, so potentially provides a humane alternative to the Fenn.