5 Comments

In the heat of public debate about cats and their impact on native wildlife, what scientific evidence did the media most use to inform?

Mostly they used Dr. John Flux’s article [1] about one cat published in the New Zealand Journal of Zoology in 2007.

Dr. John Flux's cat, Peng You, who brought home some of the many prey she killed over 17 years, 1988-2005 (Source: ).

Dr. John Flux’s cat, Peng You, who brought home some of the many prey she killed over 17 years, 1988-2005 (Source: Peng You – a fascinating predator – Hans Anderson: www.halifaxvet.co.nz).

Dr. John Flux’s 17-year record of what his cat, Peng You, brought to him made it onto TV3’s Campbell Live, into the print media – like the Listenerseveral newspaper articleseditorials, and commentary, and, of course, specialist weblogs.

John was invited to give a public talk to describe his work at New Zealand’s National Museum.

John concluded publicly that cats are a “beneficial urban predator” and that “…they are probably okay in NZ bush since, on balance, their positive effect in suppressing rodents far outweighs their negative effects on bird predation.”

5 flaws in John’s data

I wouldn’t usually single out a colleague’s work for critique in this forum, especially when it is the record from just one cat, but the use of John’s article in the media and John’s public conclusions during the debate make such critique inevitable and necessary.

There are five reasons why what John’s cat dragged in cannot be used as evidence for low cat impact or that cats are a benefit to native animals:

The New Zealand Journal of Zoology - publishing zoological science from New Zealand, and particularly conservation biology,  and pest control.

The New Zealand Journal of Zoology – publishing zoological science from New Zealand, particularly conservation biology and pest control topics.

1. prey that cats bring to their owners is a fraction of all the prey killed,

2. cats bring a biased sample of prey species to their owners,

3. the native animals killed will be replaced (recolonisation),

4. where there is more than one cat there will be more killing, and

5. John’s cat hunted from a largely exotic, non-native fauna.

I will explain each of these reasons in turn and in detail in my next four posts to reveal that John’s data cannot be used to reach the conclusions he has. For the moment, however, I address the problem of science communication that the use of John’s article illustrates.

Science communication bias

A recurrent complaint about the media in public debates that can be informed by science is that the wrong type, or the poorer quality science, often gets attention. This occurs, in part, because the media seeks to generate an adversarial discourse. Scientific adversaries and contradictions in scientific information are sought, even where none exist.

Such is the case over the #catstogo debate. Although John’s data and conclusion about the benefits of cats for native wildlife has five serious flaws, his was the single most reported science in the debate about cats and native wildlife.

What John’s cat brought to him received as much media attention as all the other NZ science and scientists on the topic combined. Better quality science from research groups at UniTec Institute of Technology [2], Otago University [3], and Auckland University [4], to name just a few amongst many others [5], received much less attention.

Peng You huting from a tree (Source: Flux, J 2010, New Zealand Journal of Zoology)

Peng You huting from a tree (Source: Flux, J 2010, New Zealand Journal of Zoology)

The media failed to consider the better data and conclusions of colleagues because John and what his cat dragged in is a cute story and his scientific article was ‘low hanging fruit’.

John’s article became the New Zealand Journal of Zoology’s most downloaded article. I suspect that if John’s article had not been published better science would have been represented by the media during the debate and NZ’s public would have been better informed.

The media is not expert in interpreting science and we should not expect it to be. Thus, the onus is also on us, scientists, to improve the standards of what is published in New Zealand’s scientific journals.

Science publication standards

The importance of the relationship between science and the media, and the potential for the media to get it wrong, raises the issue of whether or not John’s article should have been published by a scientific journal at all.

The article is just a detailed anecdote about one cat and, in my opinion, should not have found its way into one of New Zealand’s peer-reviewed scientific journals. It would have been better as a story in a local magazine for a special interest group. The New Zealand Journal of Zoology should have been more discerning.

When cutesy science like John’s is published in scientific journals it is made to appear credible to the media and can be used to manufacture adversarial discourse rather than to generate solutions-focused debate. Apparent disagreements amongst scientists and scientific data frequently result in policy inertia where none should, and progress is stymied.

Bibliography

1. Flux JEC: Seventeen years of predation by one suburban cat in New Zealand. New Zealand Journal of Zoology 2007, 34:289-296.

2. Aguilar GD, Farnworth MJ: Stray cats in Auckland, New Zealand: Discovering geographic information for exploratory spatial analysis. Applied Geography 2012, 34:230-238.

3. van Heezik Y, Smyth A, Adams A, Gordon J: Do domestic cats impose an unsustainable harvest on urban bird populations? Biological Conservation 2010, 143:121-130.

4. Gillies C, Clout M: The prey of domestic cats (Felis catus) in two suburbs of Auckland City, New Zealand. Journal of Zoology (Lond) 2003, 259:309-315.

5. Langham NPE: Feral Cats (Felis-Catus L) On New-Zealand Farmland. 2. Seasonal Activity. Wildlife Research 1992, 19:707-720.