After news of a now-canceled children’s cat hunting contest made international headlines this week, the usual suspects came out of the woodwork with wild, unsupported claims that cats — not humans, not human industrial processes, not human-driven habitat loss, wind farms or agricultural pesticides — are singlehandedly responsible for wiping out New Zealand’s native birds and the extinction of an arbitrary number of avian species.
One of the people leading the charge is Helen Blackie, a “biosecurity expert” who told the BBC that cats are responsible for the extinction of six native bird species in New Zealand.
Blackie doesn’t say where she got that information, but noted cat-hating Kiwi Gareth Morgan’s site claims that cats have killed nine native bird species, and attributes the information to a study, “A global review of the impacts of invasive cats on island endangered vertebrates.”
The “study” was published by academics in Spain and California without boots on the ground in New Zealand and is not actually a study at all. It’s a meta-analysis of prior studies, none of which count the number of feral, stray and pet cats in New Zealand, nor do they offer anything resembling a measure of how many birds are actually killed by cats.
Notably, the study does not say cats are responsible for the extinction of nine bird species.

Much like their US bird-conservationist counterparts, the authors of the study cannot say how many cats actually live in New Zealand and have no observational data about feline predatory habits.
They rely on the same methods the US studies do, which is to say they collect data from unrelated studies — including a study measuring the impact of all predators on wildlife in the aftermath of wild fires in urban environments, a study on the way pet cat personalities impact how their owners view them, and a study on cat behavior in Culver City, California — stir the data into a pot of numbers, and massage the numbers until they get the desired results.
In this case, the “desired results” are any suitably impressive-sounding figure for the total number of native birds killed by cats in New Zealand. The authors aren’t conducting a scientific investigation to find out how those native birds died, they’ve already decided that cats are the reason and they’re misrepresenting data from unrelated studies to support that conclusion. That is not science.
Of course their conclusion has no basis in reality. How is it possible that a bunch of researchers on entirely different continents are able to come up with accurate figures on cat predation in New Zealand without any actual data about cats in New Zealand, without a population count of cats in New Zealand, and without a single observational study to draw information from?
How does a study of coyote and cat interactions in Culver City, California have any bearing on cats killing birds in New Zealand, an island country 6,700 miles away with habitats that bear little or no resemblance to California? Coyotes don’t even exist in New Zealand!
How does a self-reported questionnaire about the personalities of pet cats by American cat owners tell researchers anything about the behavior of feral cats in rural New Zealand?
How does a study about the Persian squirrel on Greek island ecosystems tell a research team anything about the impact of cats on flightless birds in a completely different environment, in a different part of the world, with different types of trees and cover, different native fauna and weather systems?
How does a study of alpine ecosystems inform estimates of cat predation in the temperate and subtropical ecosystems of Aotearoa?

This sort of buffet-style, cherry-picking nonsense wouldn’t pass muster in an undergraduate class in the hard sciences, yet somehow it’s not only published in peer-reviewed conservation journals, it’s reported breathlessly and credulously by reporters at outlets like NPR, the BBC and the Guardian, who don’t even bother to read beyond the abstract.
Their claims are further undermined by their inexplicable assertion that feral cats and domestic cats are not the same thing, when in fact they are the same species: felis catus. They are indistinguishable because they are the same. They look identical and have the same genetics. The only difference is that house cats have homes and ferals do not.
No one is claiming that cats don’t have an impact on the environment. It would be foolish to think they don’t.
But if anyone — especially journalists with influential platforms and researchers cloaked in authority thanks to the veneer of real science — wants to make the case that cats are the primary force leading to declining numbers of native bird populations, then the burden of proof is on them, and it’s a high one.
We’re talking about life here, the lives of fully sentient animals with their own rich internal thoughts and feelings. You don’t just casually call for their extirpation or send children off with rifles to arbitrarily shoot them like little serial killers in training.
If you want to make the case, do the work. Get the grants. Hire the personnel. Do it right. The Washington, D.C. Cat Count even has a free toolkit for other communities to conduct their own feline census, so they can make informed decisions. But if you’re unwilling or unable to do the work, then stop spreading misinformation, because it has tragic consequences for real-world animals, and their blood is on your hands.
Top image credit Aleksandr Nadyojin/Pexels