What is Australia's population "carrying capacity"?

The population of Australia is now over 22.5 million and increasing rapidly, currently at a rate of 1.7% increase per year. Despite the deceptively small number, it still means a doubling of population every 41 years, and the subsequent increases of food, water, infrastructure, environmental degradation and housing. Opinions differ, but economic and politics demand ongoing and maximum population growth for their own agendas.

What the experts say – Tim Flannery

Professor Tim Flannery, Australian of the Year 2007, calculated a long-term carrying capacity of between 8 million and 12 million. We had that population in 1950 and 1968 respectively, not so long ago. The population is now over 22.5 million and increasing rapidly, currently at a rate of 1.7% increase per year.

Despite the deceptively small number, it still means a doubling of population every 41 years, and the subsequent increases of food, water, infrastructure, environmental degradation and housing.

Human, social and economic systems must remain within the carrying capacity of Planet Earth. Carrying capacity is defined here as the maximum number of human population that can be supported by a particular ecosystem or eco-region or physical landscape on a continued basis without irreversibly degrading the health and ecological processes.

His report, Tim Flannery - Biological considerations in determining an optimum human population for Australia
Our diversity of species in Australia is extremely high, with slow growing and reproducing plants and a very small number of warm-blooded carnivores, with a correspondingly minutely adjusted ecosystem incorporating highly specialised characteristics and co-operative behaviours. We do not have the mountainous and fertile soils with predictable seasonal patterns of Europe.

On the contrary, Southeast Asia has very productive soils, plentiful rainfall and plenty of sunshine, with a large ability to provide food for cheap. Australia has the oldest soils on the planet - very depleted, dependent on fertilisers, plentiful sun shine, but rainfall is the limiting factor.

The world ability to supply food for a growing population depends on the population carrying capacity. The population carrying capacity depends on the soil quality and the level of technology applied.

Australia's unique landscape and environment
With Australia's population projected (boosted) to reach 35 million by 2049, critics continue to express concern about the pressure this growth will place on resources.

Humans are large warm-blooded omnivores. They have high energy demands. This makes them potentially vulnerable in Australian environments. Human populations in Australia have always been small and dispersed, being an order of magnitude or more smaller than the average density found on other continents (Birdsell 1953).

Virtually all hunter-gatherer societies seem to possess a 'golden rule' of population. This is, that in "normal" times, the human population of a given area rarely exceeds 20-30% of the carrying capacity of the land. (Sahlins 1968).

Surely, Flannery states, It would appear to make good sense to observe the 'golden rule' of population in determining Australia's 'carrying capacity'.

1994 Australian Parliament House of Representatives Standing Committee

In late 1994 The Australian Parliament House of Representatives Standing Committee on Long Term Strategies delivered a report entitled Australia's Population 'Carrying Capacity'. One Nation—Two Ecologies. This report argued that Australia should adopt a population policy.

Obviously, it's worrying that the population trajectory has most likely already exceed the long-term carrying capacity.

Australian Academy of Sciences Symposium:

In 1994, Australian Academy of Sciences held the Symposium, "Population 2040: Australia's choice". The joint statement said:
the quality of all aspects of our children's lives will be maximised if the population of Australia by the mid-21st Century is kept to the low, stable end of the achievable range, i.e. to approximately 23 million.

Australia's land mass, though large, is less rich than other continents in many biologically important elements. As a consequence, its ecosystems are relatively fragile, and human impact on the environment is particularly severe. This impact has been documented even for the relatively sparse, low-consumption Aboriginal societies. The impact of modern Australian society is much more severe.

Stable Population Party of Australia

The Stable Population Party of Australia is advocating a stable population at 23 million in line with the Australian Academy of Science findings. To obtain this option we would need to have zero net migration and phase out the baby bonus.

MP Kelvin Thomson

Kelvin Thomson's 14 Point Plan for Population Reform aims to set out the reasons why I believe the world’s projected population levels are too high and unsustainable – global warming, food crisis, water shortages, housing affordability, overcrowded cities, transport congestion, fisheries collapse, species extinctions, increasing prices, waste, war and terrorism.

We are already in “ecological overshoot”. Land size does not equate to carrying capacity. Our lifestyles, for the most, are spiraling downhill due to the stress of population growth and the associated costs and loss of social capital. Once ecosystems melt down, they are gone. It doesn't depend on what we want, but how many people our land can realistically and desirably support. Big is not necessarily better.

Treasury 2010 Intergenerational Report

According to the Treasury 2010 Intergenerational Report, the best way to respond to the economic and fiscal pressures of an ageing population is to support strong, sustainable economic growth. Economic growth will be supported by sound policies that support productivity, participation and population — the '3Ps'.

They assume that if Australia's productivity growth could be increased above the long-run average, the economy would be bigger, living standards would be higher and fiscal pressure from the ageing of the population would be reduced. If, for example, annual productivity growth was to average 2 per cent over the next 40 years, then:

• annual real GDP growth would average over 3 per cent over the next 40 years and the economy would be $570 billion bigger in 2049?50; and
• real GDP per capita in 2049?50 would be 15 per cent (or around $16,000) higher.

It assumes that the main purpose of the economy is to GROW, even to our own detriment. Costs of economic growth include increased pressure on social relationships and environmental degradation, whilst non-welfare issues include distribution, poverty and intergenerational equity. Also, GDP per capita is a better measure of the economic well-being of a country than total GDP, as it takes into account population size – very populous countries may have very large overall GDP, but when divided by population size the resultant GDP per capita figure will give a much clearer indication of the country’s comparable wealth.

The same baseless argument of "keep the economy growing" is being proved as a sham. As for a worry of populations going down, why is this a bad thing? While GDP overall may decrease, GDP per person (or GDP per capita) will certainly increase. Higher populations don't create wealth, it just redistributes. Production is the engine room of economic growth!

So as populations go down, the average citizen is better off. Only people reliant on growing markets ie, CEO's, politicians, producers of consumer goods etc would be worse off.

Japan is presented as a "loser" in the population stakes, where India is "the big winner". Makes you wonder about the value of winning that particular economic growth race!

Tony Burke Minister for Population

The nation's first Population Minister, Tony Burke, ruled out setting population targets in the strategy that he will draw up over the next 12 months. He ruled out a model that could take into account lour “chronic” labour shortages, with any precision. With a growing population happening "no matter what", the federal government would not focus on an arbitrary population target. His recent “report” is a sham. Our population growth is not arbitrary or inevitable, but manipulated by political decision. What about shortages in water, energy, food, land and funds for education and training?

Tony Burke needs to take a holistic viewpoint, and not just base his assumptions on limitless growth. 

Global threats
We are not the only country in the world that has raised the population question. Global population is an increasing threat, and once natural resources and amenities outstrip supply, we could be facing famine, lack of potable water, pollution of oceans and waterways, and environmental degradation - leading to further decline of species, and extinctions. Afghanistan, Bangladesh and Pakistan are other Asian countries that are facing food security problem due to limited arable land to support the ever increasing population.

Evolutionary Trait to expand
An evolutionary trait of species is to consume and increase numbers and overtake the territories and resources of other species is very well developed in humans. Once populations tip over a level that supports an economy of scale, the downside could be disastrous.  As species capable of a moral and spiritual dimensions, can we justify the mass extinctions of other species on the planet, for our own expansion? Each species lost means a decline in the health and robustness of our ecologies.

As Dr. Paul Ehrlich said, All causes are lost causes without limiting human population.

Birdsell, J.B. (1953). Some environmental and cultural factors influencing the structure of Australian Aboriginal populations. American Naturalist 87:171-207.

Sahlins, M. (1968). Notes on the original affluent society. Pp 85-89 In Man the Hunter. R.B. Lee & I DeVore (eds). Aldine Publishing Company, Chicago.