Has the domestic cat become a pest in preying on 2,084 species worldwide?

Has the domestic cat become a pest?
Two useful tags. Click either to see the articles: Toxic to cats | Dangers to cats

Introduction: This article conerns a new study on cat predation. The first point to make is that the study I’m referring to concerns “free-ranging cats (Felis catus)”. That’s important because across the world there are many small wild cat species which prey upon many types of animal. This study and this article is about the domestic cat allowed outside. There is an overlap with stray cats and feral cats. I don’t think you can differentiate between the two sometimes. Has the study differentiated between these types of cat?

Caveat: people should know that this study was authored by Dr. Christopher Lepezyk of Auburn University in Australia. We know that Australia is engaged in a war against the feral cat and the indoor/outdoor cat. Historically, Australian scientists have exhibited, in my view, a bias against the domestic and feral cat because of predation on endangered Australian native species. I don’t know if we can completely trust this current report for that reason.

Collectively, our findings demonstrate that cats are indiscriminate predators and eat essentially any type of animal that they can capture at some life stage or can scavenge. This dietary breadth lends further evidence to the myriad ways that cats can (or may) interact with native species and disrupt ecosystems because they are not dependent on any one trophic level or taxonomic group.

Study: A global synthesis and assessment of free-ranging domestic cat diet

The Times reports on this study today. They say that this is “the most comprehensive global study of its kind”. The conclusion is that “domestic cats will eat just about anything that they can kill and that includes hundreds of threatened species”.

The report/survey is published in the journal Nature Communications. And interestingly, the Times journalist asks whether “an animal domesticated to banish rodent pests has become a nuisance itself?”

That is actually a good question and it reminds us that the domestic cat was at first a working cat keeping down rodent populations on farms. They were useful as indoor/outdoor cats and often barn cats. But then with the explosion of cat domestication they became a nuisance to some countries particularly Australia where the authorities are particularly sensitive about predation on their native species.

The domestic cat is not a nuisance to Germans living in Germany. They don’t complain about the domestic cat killing native species. It’s probably because the typical German cat owner is responsible in their caregiving. We have to refer the matter back to human behaviour at the end of the day.

Australia’s native species are under threat primarily from human population expansion. There is mass immigration into Australia with 500,000 people emigrating to Australia last year as I understand it. That inevitably leads to housebuilding which also inevitably leads to destruction of wildlife habitat. Australia’s don’t like to talk about that. They prefer to blame the domestic cat.

But there is a valuable point here which is that the cat does kill small native species in Australia and around the globe in large numbers and sometimes there are endangered for whatever reason.

As my title states, the free ranging domestic cat was found, in the study, to hunt or scavenge more than 2000 animals of a wide range from the common dwarf skink to the American bullfrog.

350 species of ‘conservation concern’ are consumed by the free ranging domestic cat. These include the western quoll, a carnivore found in Australia and which is listed as near threatened by the Red List. The cat also preys on the green sea turtle and Newell’s Shearwater, a critically endangered sea bird found in Hawaii.

The Hawaiians, understandably, are very concerned about feral cat predation on the bird population. There are too many feral cats on Hawaii. They are there because of irresponsible cat ownership. Ultimately, the free ranging cat problem originates in humankind’s relationship with the domestic cat and whether people are responsible or irresponsible in cat ownership.

The study describes how cats have eaten several species which have now become extinct including the Paradise parrot.

The study concludes with the words that cats “are indiscriminate predators and eat essentially any type of animal that they can capture”.

The animals include about 9% of all known bird species, 6% of mammal species and 4% of reptile species.

The study scientists built the largest database of cat diets. Of the 2084 species eaten by cats, 981 (around 47%) were birds, 463 were reptiles (22%) and 431 were mammals (21%), 119 were insects (6%), and 57 were amphibians (3%).

Separately, in another study referred to by The Times journalist, Rhys Blakely, a study published in 2022 from the UK estimated that the domestic cat kills between 160 million and 270 million animals annually in the UK. They estimated that 25% of them were birds.

They think the figure may be higher because the estimates were based on a domestic cat population in the UK of 9.5 million which has arisen to around 12 million during and since Covid.

The lead author of this study from the University of Exeter is Professor Robbie MacDonald who said: “Studies on the scale of predatory behaviour by cats, whether it is the number of species killed, or the numbers of animals killed, always generate large numbers.”

And an RSPCA spokesman chipped in by saying that “The impact of domesticated cats on wildlife populations is subject to intense debate. On an individual level, predation on wildlife is likely to cause considerable suffering, which is of course concerning to both animal charities and many cat owners to. However, restricting a cat’s natural behaviour can also have a detrimental impact on their well-being. The RSPCA recommends that cat owners reduce the opportunities for predating on wild birds and other animals by restricting outdoor access.”

In Australia, there is a general movement towards keeping domestic cats indoors full-time and ACT leads the way in this regard but they are acting humanely in my view, which cannot be said about all jurisdictions in Australia where the feral cat is heavily persecuted and killed in anyway possible.

Study referred to: Lepczyk, C.A., Fantle-Lepczyk, J.E., Dunham, K.D. et al. A global synthesis and assessment of free-ranging domestic cat diet. Nat Commun 14, 7809 (2023). https://doi.org/10.1038/s41467-023-42766-6


My personal conclusion is that there are, indeed, too many domestic cats on the planet today. There needs to be a reassessment about cat domestication. There needs to be a gradual winding down or phase-out of cat domestication and the breeding of domestic cats often informally through irresponsible cat ownership. And there needs to be a reassessment of cat breeds and whether some should be discontinued because they are inherently unhealthy. There’s lots to do in respect of the domestic cat’s place in the world as things are changing. Because nature is under unprecedented pressure from human behaviour of various kinds including causing global warming, the domestic cat allowed outside is being scrutinised more critically. It’s time for a reassessment of cat domestication and whether it has become a failure in some respects.

Please search using the search box at the top of the site. You are bound to find what you are looking for.

Leave a Comment

follow it link and logo