Who let the cats out?

We’ve worshipped them since ancient times. They’re our feline overlords. Cats. We love them as pets – and indoors.

But did you know that cats have a dark side? Outdoors, they are threatening our native wildlife.

The cat is out of the bag. Source: Sam Craig via Flickr.

How bad is it?

Feral cats present such a huge threat to our native wildlife that the Australian Government declared them a nationally significant pest species in 2015. Feral cats are estimated to kill 75 million native animals per day in Australia – that’s more than three times the entire human population of Australia, and all in just 24 hours. Even when they aren’t hunting wildlife, the mere presence of cats can change the behaviour of wildlife, such as how and when they feed, and how they use their environment. This may not seem like a big deal, but these changes can impact wildlife survival.

The reason cats pose such a danger and are a hugely successful predator in Australia is because there are no large native predators to control their populations. This leaves cats free to prey on small animals, such as mammals, birds, frogs, lizards, and insects, many of which are native and endangered.

Felix doesn’t see the problem. Source: Etienne Valois via Flickr.

But what about my cat?

I know what you’re thinking. My cat would never hurt a fly! Okay maybe my cat would pin it down by the wing and play with it for about 20 minutes. But hey, that’s just a fly right?

It’s true they are our faithful lap-warmers indoors, but don’t be fooled by those purrs. Cats are natural born killers, an instinct that jumps into overdrive when they get outdoors.

In Australia, we love our cats. In fact, we have around 3.9 million pet cats, with about 30% of all households having at least one cat. This makes them the second most popular pet (you’ve won this round dog people). What’s more is that over half of us are letting our little predators outside.

Our pet cats have the potential to have a bigger impact on our native wildlife than even feral cats. This is because their numbers can increase above the natural carrying capacity of the environment. In other words, because we feed our cats, they are not dependant on catching prey in order to survive.  So, a larger number of cats can live in a certain area than would be the case if they were feral and fending for themselves. On top of this, because we keep our cats in good nick, they are even better at catching prey.

A larger number of cats equals a larger number of wildlife killed by cats. But wait, there’s more! Native species are already dwindling in urban areas due to the effects of city-living, so the impact of cats is even harder-hitting on those species.

If you add all of these factors together, what you get is a major threat to our native wildlife – and we are opening our doors to contribute to this.

Estimates of kills by domestic cats are in the millions in the UK and Canada, and in the billions in the US. While there hasn’t been as much research in the Australian context, one estimate suggests pet cats kill 96 million vertebrates (animals with spines) per year.


So what can we do?

Well, it’s pretty easy actually – Don’t let your cat outside.

We don’t allow our dogs to wander the streets freely, so why do we do this with our cats?

Our cats can have very happy lives indoors. In fact, an indoor-only cat has a longer average lifespan than one allowed outdoors. This is because illness, cat fights, and traffic-related accidents are reduced or avoided altogether.

But if you simply must have your little fur friend explore the outdoors, then only let them out during the day. Most of our native species only come out at night, and cats have great night vision for hunting them. This means that night time is prime time for cats chowing down on our precious native animals. Better yet, invest in an outdoor cat run that gives the best of both worlds.

As urban areas spread and natural areas recede, it becomes even more important to take steps to protect our native wildlife in any way that we can. It may be simple, but closing the door to kitty can help in a very big way.

4 Responses to “Who let the cats out?”

  1. Jasmin Hartel says:

    Thanks Murraya!
    It’s pretty amazing how good they are at hunting. They don’t bring all of their kills home, so your friend’s cat could be hunting even more than it seems!

  2. Murraya Lane says:

    My friends cat has dragged in magpies and other birds as well as mice and lizards so I’ve seen first hand at what efficient predators they can be! Very interesting read!

  3. Jasmin says:

    I totally agree – I had a scaredy cat that was too scared to leave our back yard (she ended up being an indoor cat after that).
    That being said, it’s hard to know what every cat gets up to and there are definitely some naughty ones out there.

  4. Isabelle says:

    I’ve seen my own scaredy cat be chased across the backyard by our chickens. (And they’re bantam chickens, mind you). So I don’t think he’s hunted a mouse in his life. That said, there’s definitely cats in the neighbourhood that should be locked inside earlier. Owners need to take responsibility.