THE POTENTIAL OF ELECTRIC-SHOCK FOR THE HUMANE TRAPPING OF BRUSHTAIL POSSUMS, TRICHOSURUS-VULPECULA

The Australian brushtail possum is a major pest in New Zealand, and a device to kill possums in the wild by electric shock has been proposed. This investigation was to determine the best waveform and energy level for an electric device to humanely kill possums. The criterion set was a shock which would cause ventricular fibrillation and result in irreversible unconsciousness within a few minutes. Anaesthetised possums were shocked with sinusoidal alternating currents, direct current bursts and impulse waveforms of varying intensities and durations. An electrocardiogram was used to monitor the cardiac response. Although sinusoidal waveforms of a long duration did disrupt the heartbeat and might result in death, even shocks of very high energy levels did not consistently result in ventricular fibrillation. The use of electricity to trap and kill possums appears unacceptable on humanitarian grounds.