Pressure from the effects of exponentially growing human population has decimated wildlife populations in countless areas all over the world. Furthermore, it has caused the extinction of many species. In addition to collisions with man-made structures, one of the most serious problems for wildlife that we are responsible for is the killing machine that is our roaming, unsupervised domestic pet. Specifically, cats and dogs.

The number of cats and dogs is very significant throughout the developing world. This is because veterinary care is good and population control is often minimal. Additionally, feral cat and dog populations that occur because we allow non-sterilized pets to roam also pose a serious threat to our struggling wildlife.

Dogs and cats disturb or kill wildlife, compete for the resources that wildlife need, and act as reservoirs for pathogens that cause epidemics in wildlife.

The Stats

Problems caused by our pets is sadly not a new issue. For example, in 1997, a study from the UK conservatively estimated that domestic cats kill a total of 92 million native species annually. Domestic cats are the most abundant carnivores in Great Britain. 

A more recent US study found that cats, both feral and domestic, kill 1.3 to 4 billion birds and 6.3 to 21 billion mammals annually. Yes, BILLION. These numbers are staggering.

Australia’s cats kill an estimated 2 billion animals every year. 

Roaming pets threaten species extinction in many isolate areas of the world. These include islands or contained areas between natural barriers such as mountain ranges. From Brazil’s greater rheas (a large flightless bird) to the unique animals of Australia, wildlife is being wiped out. Native species in isolated areas did not evolve to handle predation by cats and dogs. Therefore, native species are essentially defenceless.

Not surprisingly, Canadian wildlife is also threatened by careless pet owners. According to the Canadian Wildlife Federation (CWF), every year in Canada 140 million birds and small animals are killed by domestic cats.

Other Issues

As well as hunting, cats, dogs and their feral relatives also spread disease to wildlife.  As an illustration of this disturbing fact, dogs can give canine distemper to wolves and raccoons. And cats spread the parasite Toxoplasma gond that causes the disease toxoplasmosis which can kill any bird or mammal it infects.

Contrary to the conviction of some pet owners, there is nothing natural or kind about letting your well-fed cat or dog run loose. They are not indigenous species, they are invading species. They are not playing, they are hunting. And they are terrorize our native species who have nowhere safe to hide. Wildlife don’t have the protection from the elements, disease, predation or starvation that the domestic cat and dog enjoy. It is a very unfair contest.

One day, would you like to go for a walk and see no trace of wildlife and not hear a bird singing?

It is also important to note that allowing your pet to roam outside poses serious health issues and physical dangers to your pet. Pet ownership is not for the lazy. It is a lot of work and responsibility that should not be taken lightly. Nor should wildlife suffer because of our laziness.

Pet ownership is a global practice, the effects from which no country is immune.



In more developed countries without large remote wildlife areas part of the problem can be dealt with by well thought out and enforceable law. In most Canadian urban areas dogs are supposed to be under the control of the owner at all times when in public. For instance, leash laws in Ottawa are quite strict and require your dog to be leashed if he is on public land. This means to allow your dog to run loose outside you will need to create a fenced area on your property.

Regretfully there are many people that still allow their dog to chase wildlife despite laws to the contrary. With education and law enforcement this situation should be resolvable. Sometimes all it takes is to have a word with your neighbour who owns the errant animal.

We must all remain sensitive to the difficulties faced by our resident wildlife. Moreover, if you see someone letting their dog run loose, speak up!

For larger property owners, please keep your dog under your control at all times. Teach him not to chase wildlife. Equally important, play with your pet more often. Let him chase lots of dog toys! He will have just as much fun as he would chasing wildlife, and be much safer too.


Due to local dog leash laws, it is often easier to resolve problems with stray dogs than it is to stop cats from harming wildlife. Unfortunately residents have historically exerted a lot of pressure on our law makers in Canadian cities to continue to allow cats to roam free. However, this does not mean we should stop trying to get anti-roaming cat laws passed. 

People have tried other methods of controlling the carnage such as attaching a bell or sonic device to their cat’s collar. Sadly, this practice only decreases a cat’s predatory efficiency temporarily because cats learn how to hunt despite these devices.


Cats should be kept safe in their home, enclosed in a cat patio, or be on a leash.


Sterilize your pet to decrease the chance of creating or contributing to a feral population. Trap-neuter-release programs are somewhat effective too.

Culling feral cat and dog populations is a very effective way of helping native species survive. This also prevents very sad cases of dogs and cats trying to survive in the wild. Whenever possible, these cats and dogs should be put up for adoption rather than euthanized.


Is our responsibility to stop our carnivorous pets from continuing to torture and kill wildlife. With skillful control programs and responsible pet ownership we can reduce the number of victims.

You will be doing your pet and local wildlife a great service by keeping them safe and separate at all times.

We can make a difference.