Bob Kerridge: Campaign against cats is using shonky evidence

The "evidence" suggesting cats are killing our native birds is shonky. Photo / Getty

Over the centuries cats have endured various forms of intense persecution for a variety of obtuse reasons, and sadly this is happening here in New Zealand right now.

Environmental lobbyists and local authorities are baying for their blood, all in the good cause of conservation.

None of them are considering the moral and ethical implications of their claims, and all of them are relying on shaky science to support their arguments that cats are the number one killer of our wildlife.

It all started when Gareth Morgan very publically denounced all cats as evil in his bitter and vitriolic "cats to go" campaign, when he proclaimed to all cat owners, "That little ball of fluff you own is a natural born killer. Domestic cats are 'serial killers' who are single handedly destroying our native species."

Morgan, like many who follow him, repeatedly quote statistics gleaned from a variety of sources to support their arguments, most notably in his case the discredited "Wisconsin Study" funded by the Smithsonian Institution in 2013.

This study claimed free-ranging domestic cats kill 1.4 to 3.7 billion birds annually, representing 28.5 per cent to 75.5 per cent of the estimated land birds resident in all of North America which, if true, would equate to the total annihilation of every land bird in the region.

The "study", which was not a study but a proposal for one which never actually took place, was authored by researchers with a known anti-cat track record, one of whom was subsequently convicted for trying to poison cats. Another, when questioned on its authenticity responded, "[These figures] weren't actual data; that was just our projection of how it might be."

In Australia, a country not known for its affection for cats, published "research" by a group of environmental scientists claiming cats were responsible for the deaths of 1 million birds a day, an outrageously rounded figure further exacerbated by the statement that 99 per cent of those deaths were native birds.

If that were so Australia would be bereft of natives, where in reality only one species is extinct thanks to some land clearance for human habitation.

In New Zealand the only research that seems to be constantly quoted, and which features on the Forest & Bird website, states, "A Dunedin study suggests that our 1.4 million domestic cats kill close to 20 million animals a year, including more than a million native birds."

In fact this study involved 37 cats that had a prolific history of hunting, representing only 0.0026 per cent of the total cat population at the time, the sole purpose of the research being to measure the effect of collars and bells to reduce their hunting habits.

The study was not designed to provide a meaningful projection of the number of prey caught by companion cats, neither would it be possible to accurately project such a figure from such a small sampling.

The final example of manipulated research involves the self-appointed National Cat Management Strategy Group, (NCMSG), whose strategic outcomes include the extermination of all stray and feral cats in New Zealand, and the education of the public in understanding the potential impacts of cat predation on our environment. It will of course come as no surprise that the Morgan Foundation is an active member of that group.

In an effort to prove they had public support for some of their draconian and dangerous recommendations, the New Zealand Companion Animal Council, another member of the group, was commissioned to undertake a survey on the public response to the proposed management strategy.

The 1016 people involved in the survey were told, prior to being questioned, that "between 18 and 44 million prey items are killed annually by companion cats".

Armed with this alarming background information, which came from a 2013 research paper that has subsequently been discredited, the unsuspecting participants were asked to comment on the proposed solutions offered by the NCMSG to solve the "problem".

Not surprisingly there was general support for the recommendations, just as the researchers had planned for.

I am reminded of the old saying on how statistics can be misused. "Some people use statistics as a drunken man uses a lamp-post – for support rather than illumination."

So when it comes to statistics involving cat predation don't be fooled into believing all you hear. The sweeping statements currently abounding on this subject, using biased research to advocate controlling, trapping, and killing cats, is very dangerous and will result in the unnecessary death of many thousands of innocent felines, maybe even your own.

The last word belongs to William Lynn, research scientist in ethics and public policy at Clarke University: "As an ethicist I care about both native wildlife and cats. It is time to stop blaming the victim, face up to our own culpability and seek to 'rewild' our world with an eye to the ethics of our action. There is no justification for a war on outdoor cats, feral or otherwise, based on shaky science and an absence of ethical reasoning."

• Bob Kerridge is an animal welfare advocate based in Hawke's Bay.