Critical to any approach to management of populations of cats and dogs is an understanding of population dynamics.  There are large populations of unowned animals which contribute in a significant way to animal management issues.  We have a much better understanding, however, of owned cat and dog populations, because they are easier to survey and to manage with policy.

Owned cats and dogs:

Since the late 1980s the Australian owned cat population has steadily declined from a peak in 1988 of 3.2 million to 2.4 million in 2007.  The owned dog population appears to have stopped increasing in around the year 2000, and has reached a plateau at around 4 million.

Australia is unusual amongst developed pet-owning nations as having one of the highest rates of pet ownership, but an owned pet population that no longer grows with human population growth.  The reasons for this include (Pet populations in Australia):

• The major reason for people not owning a cat is because they ‘dislike cats'.


• Around 90% of owned cats are desexed, which has reduced the birth rate of kittens each year. This will lead to a narrow gene pool where moggies may become a thing of the past.


• The major reason for people not owning a dog is because of lifestyle or housing issues. As we get busier and live in higher density environments, it may become more difficult to be a responsible dog owner

Pets give social, psychological, health and financial benefits In order that the community can derive the benefits of pet ownership, responsible ownership is necessary to ensure companion animals are pets and not pests.

Non-owned cats and dogs:

• Non-owned cats and unwanted litters of stray and feral cat kittens can contribute up to 80% of animal welfare shelter intake (Cat Admission to Melbourne Shelters-Marston)


• These non-owned cats will continue to cause a problem until there are better ways to manage these populations.  The Victorian Government has a campaign, Who's for Cats?, to address this issue


•  As not all non-feral dogs live in an urban environment, consideration of free-roaming dogs in a remote Aboriginal community is important (Population study of free-roaming dogs) Under optimal conditions, their population can triple every year.


• Studies on the population dynamics of the free-roaming dogs, have found that mortality of pups is increased during the wet season when tick infestation was greatest.  Population are also affected by infection with Ehrlichia platys +/- co-infection with Babesia canis. Both are transmitted by the brown dog tick, found to be a common external parasite on the dogs.

Public perceptions

It is important when developing policy to manage non-owned populations that a good understanding of public views is ascertained.  Surveys (Cat management for Magnetic Island) and a good scientific understanding of pet behaviour, nuisance and ownership  (Cats - perceptions and misconceptions) is critical. 

Management of reproduction:

Good knowledge of cat and dog numbers is necessary before devising strategies to manage their populations. A strategic response that targets an identified issue is recommended. (The issue of unwanted animals)

Non-surgical reproductive control for cats and dogs is a rapidly advancing area (Advances in reproductive control technology), however more research is required to deliver what could be the ultimate tool in animal population management.