the implausibility of possum peppering

By Alison Campbell 17/07/2010

This morning’s Waikato Times carried the following headline: Heavens aligning for fiery possium cure. Now, there’s a lot of pressure on to find viable alternatives to 1080 as a means of controlling possums, but somehow I don’t think the method described in the Times story is going to take off.

The news item tells us that possum skins burnt to ashes under the right alignment of the Moon and stars could be an alternative to 1080 – & the group promoting this is asking for $330,000 of Environment Waikato funding to demonstrate it. My first thought, on reading this, was ‘you have to be joking!’ Subsequent thoughts were much the same. Why? 

Well, the Times story goes on to quote the funding application:

The method requires an understanding of how energies from the universe affect life on Earth. The appropriate alignment of Earth, Moon, Venus and Scorpio at the time of burning is necessary if the method is to work well and possums are best harvested at this time. The carbon from the burnt skin interferes with the reproductive energy of the possum.

(And aparently the soil has to be damp when this mix is broadcast over pastures & forests.) Now, this is nothing more than a mix of pseudoscience & magical thinking; science it is not. The mention of planetary alignments & a sign of the zodiac signals that we’re hearing about astrology. The idea that the position of the planets & their alignment with arbitrarily-named random patterns of stars can have any influence on life on Earth has been tested – & found wanting. (You can read an extended summary of the original research here). To suggest that the same factors would have any impact on possums is to demonstrate magical thinking.

The vague, generalised mention of ‘energies’ is another clue that we’re dealing with pseudoscience. As Brian Dunning says, terms like energy fields, negative energy, chi, orgone, aura, psi, and trans-dimensional energy are utterly meaningless in any scientific context. Claims about ‘energy fields’ & their therapeutic application in humans have been debunked on more than one occasion (see here & here, for example), & there’s no good reason to expect that these nebulous constructs should exist in possums.

In other words, there’s no plausible mechanism by which ‘possum peppering’ might work. Tellingly. the  article tells us that a 1998 trial of possum peppering saw an increase in possum numbers, & a study published in the New Zeland Journal of Ecology similarly found no deterrent effect of the ‘treatment’.. It should be fairly straightforward to test ‘peppering’ in the lab (& for rather less than $300,000), but given that the results of previous studies are negative, any new trials should be funded by the method’s proponents, & not by EW ratepayers.