The debate on Australia’s future population size has taken a welcome leap forward in early 2010. Much attention is focused on the Treasury estimate of 36 million Australian residents by 2050. Most of the reasons given for why this is not a desirable outcome centre around quality-of-life issues and whether our natural environment can withstand the impact of so many Australians living relatively wealthy lifestyles requiring high levels of consumption. However, one question that is hardly ever raised is whether we can, in fact, feed 36 million people.

Historically, being a net exporter of food, we have rejected the idea that Australia might one day lack the ability to sustain its human residents. But what do the numbers say? And will our capacity to produce food in the future be the same as today? These are important questions for anyone with a stake in Australia’s future – in other words all current and future parents.

So what do we currently eat? Let’s divide up our diet into fruit and vegetables, grains and pulses, and meat. (Dairy products and fish will be mentioned later.) The most important part of these three categories is grains and pulses – not only because they form our staples (e.g. breakfast cereals, pasta, bread and rice etc.) but because, as you will see, a very large proportion go into making meat.

However, let’s start with fruit and vegetables. This is a large and very diverse category so the simplest way to view production and consumption is in monetary terms. From the document “Signpostsvfor Australian Agriculture” (and a shorter
) produced by the National Land and Water Resources Audit of the federal government we learn that,

“Australia became a net importer of fruit in 2006–07 and has been a net importer of vegetables since 2002–03.”

They base this on “gross value of production” data from a report by ABARE, the Australian Bureau of Agricultural and Resource Economics (see page 7 of the “Signposts” report above):

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It is also worthwhile noting the comment that,

“Since 2000–01, the main constraint on the industry’s productive capacity has been climate variability and the impact of two severe droughts in quick succession on production and farm profitability. Low water availability from natural rainfall and restricted irrigation water allocations have been key production limiting factors.”

This suggests that climate change and finite resources (e.g. water) are already impacting on our food production. This is also indicated by another comment:

“There have been rapid rises in input costs, particularly fertiliser and fuel.”

So, in terms of Australia’s fruit and vegetable production, we are not even supplying all of the needs of our current population. Supplies of fruit and veg for a growing Australian population will be dependent upon the willingness and ability of other nations to sell us this food.

Now to the grain category. The “Australian Crop Report” of February 2010 compiled by ABARE gives historical and current information on Australian grain production, consumption and exports. Tables 5 and 6 from this document show the numbers for “Australian supply and disposal of wheat, oilseeds and pulses” (consumed by humans and animals) and “Australian supply and disposal of coarse grains” (predominantly consumed by animals) respectively for the financial years 2004-5 to 2009-10 (predicted).

For wheat, we see that, in an average year and under current conditions (fuel, fertilizer, climate), Australia can produce about 22 million tonnes (Mt) although drought can slash this by over half (see 2006-7 and 2007-8):

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Note that in the drought years domestic use and exports for wheat were similar, i.e. we used half or more of what we produced. A bit over one third of our domestic use of wheat is for direct human consumption. The rest is used to feed animals and to provide seed for the next year’s crop.

The statistics on grain can be complicated by the existence of stocks that are carried over from year to year and also the fact that Australia can import grain as well as export it. For example, in the drought year of 2006-7 Australia produced 0.57 Mt of canola (our main oilseed crop) but consumed 0.59 Mt and exported 0.23 Mt! However, in a good year we export about twice as much canola as we use. In 2008-9 we produced 1.9 Mt of canola.

For pulses, (e.g. lupins, field peas and chick peas) the bulk of our production (usually about 1-1.5 Mt) is consumed domestically.

Coarse grains are the other major category of our grain production and include grains such as barley, oats, triticale, sorghum and maize. Our total coarse grain production, consumption and exports in Mt looks like this:

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Less than one tenth of our domestic use of coarse grain is consumption directly by humans – the rest goes to feed animals and supply the grain for the next year’s crop. For example, in 2008-9, 0.4 Mt of total coarse grain production was consumed directly by humans while 5.1 Mt went to Australian animals. When combined with domestic wheat consumption we can see that, on the whole, far more grain in Australia is consumed by animals than humans.

So let’s look at meat. In the last few years our production and consumption of meat has varied by less than 10%. The most recent numbers (taken from ABARE’s “Australian Commodity Statistics 2009”) are shown below.

Meat (Mt) Red meat production Red meat
(by humans)
Red meat

Pig meat

Poultry meat



1.6 (1.1)




We can see that Australians consume about half of the red meat we produce. (Per capita consumption figures from ABARE – not shown here – indicate that only about 70% of this consumption is by humans.) In Australia, most of our red meat production is from sheep and cattle fed by grazing. Less than 30% of our cattle are fed on grain before sale (i.e. “finished on grain”) and, since “finishing” usually occurs for a lesser fraction of the lifespan of cattle for sale, we can see that our red meat production is not largely dependent on grain. Most of the enormous volume of grain consumed by animals in Australia goes to pigs and chickens. Furthermore, the per capita consumption figures indicate that we eat more pig and poultry meat than red meat in Australia. While we do not import poultry meat, we do consume 95% of what we produce and so export only 5%. In contrast, our consumption of pig meat is 50% greater than our production. Since pig and poultry production is almost entirely dependent on grain, rising grain prices directly affect the larger part of our meat consumption.

So far in this analysis I have not addressed seafood or dairy products. Production from Australia’s Australia’s wild fisheries, (as in the rest of the world), is in decline and although there is some substitution for this loss by aquaculture, aquaculture itself is largely dependent on wild-caught fish for fishmeal (a major component of commercial fish food). In 2007-8 Australia’s wild fisheries and aquaculture production totaled 0.11 Mt. We exported 0.04 Mt of edible products but imported 0.20 Mt – nearly twice as much as we produced ourselves. During the past decade, Australian exports of dairy products have been in decline as both our domestic consumption of dairy products has been rising while water allocations for pasture irrigation have been cut due to droughts. In 2007-8 the average Australian consumed 104L of milk and 32 kg of milk products, e.g. including cheese (which lies somewhere between our kg per capita pig and poultry meat consumption rates). Although less than 10% of Australian cattle are dairy cattle, these tend to occupy our best irrigated pasture country, requiring large inputs of fertilizer, water and energy.

From the broad summary above we can draw the following conclusions. Under current economic, environmental, energy supply and climatic circumstances:

  1. We are currently not self-sufficient for fruit and vegetables.

  2. In a good year we could supply about 3x our current population with wheat but, in a drought year, less than 2x our current population.
  3. We could supply 2x our current population with red meat in normal – not drought – years.
  4. We could probably double our pig and poultry meat production if we consumed all our course grain production domestically (i.e. no exports) and significantly reduced our wheat exports. This is not possible under drought conditions.

A population of 36 million Australians is approximately a 64% increase over today’s number. The rough analysis above shows that, in a drought year and under current conditions of resource supply, we would be nearing the limits of our ability to provide our own population with food and we are already beyond the limits of our ability to produce fruit and vegetables for ourselves. We would not be “food secure”.

Finally, let’s take a quick look at future trends that might impact on our food production. As the driest continent spanning a tropical to temperate climatic zone Australia is very vulnerable to the effects of climate change. There are estimates that, for every 1°C rise in temperature over 30°C during crop flowering, grain production falls by ~10%. We now appear to be locked in for at least a worldwide average 2°C rise and,, in that case, Australia can expect to experience an even greater change. Thus, we can expect a decline in grain production considerably greater than 20%. The droughts of 2006-7 and 2007-8 – that slashed grain production by about half – may be a preview of that. The drying of the Murray-Darling basin (that has been attributed to climate change) and the resultant collapse of fruit and vegetable production (that has already affected our self-sufficiency in this area) may be a warning of what is to come.

Another severe and underappreciated limit on agricultural production – especially for Australia with its ancient and nutrient-poor soils – is future fertiliser availability. One method for predicting future minerals production is Hubbert
(HL) analysis. HL analysis of phosphate rock production by Déry and Anderson shows that ~75% of the world’s easily accessible phosphate may already have been mined! (P = production in Mt, Q = cumulative production in Mt):

Image Removed This conclusion is supported by an analysis of annual and cumulative production curves by Ward. As a recent investigation in the scientific journal Nature noted:

“…estimates [of phosphate reserves] all suffer from a lack of reliable data. Most of the world’s phosphate-mining companies are integrated with fertilizer firms and the mines are either owned by the companies or are under state control…. As a result, it is difficult to get accurate, independent information on phosphate reserves.”

The spectacular price rises for phosphate, nitrogen and potassium fertilisers in recent years (see page 97 of ABARE’s “Australian Commodity Statistics 2009”) do not bode well for fertiliser availability/affordability in coming decades.

Australia’s broadacre agriculture is also highly dependent on oil and gas production – for powering farm machinery, producing pesticides and herbicides, generating nitrogenous fertilizer and for transport. A recently published analysis by those scientists who have been most successful in predicting recent oil production trends indicates that the world’s maximum possible level of oil production (the “peak”) was most likely reached in July 2008 and the long term trend of oil production will be down in future (see Figure 15 from their study below. Note: Mb/d = millions of barrels per day, IEA = International Energy Agency, NGL = Natural Gas Liquids). By 2030 – which is only half way to 2050 – we can expect crude oil production to be, at very best, 7% lower than today and it will probably be far lower. By 2050, when Australia’s population is thought to be reaching 36 million, global oil production will be in its twilight. The green revolution – and the globalization of world agricultural markets that cheap oil has supported – may be at an end. If we cannot then produce sufficient food for ourselves, there will be no other nation to turn to for help.

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By 2050, if Australia is to survive as a nation, our agriculture will need to have adapted to climate change, instituted radical measures to recapture and recycle nutrients (e.g. using human and animal wastes as fertiliser) and have, somehow, compensated for the loss of cheap and plentiful fuel. We have not even begun to move in the direction of the more local, intensive but lower energy agriculture that will be necessary and we have less than four decades to accomplish it! In the face of these challenges it is highly unlikely that we will be able to support 36 million people. Indeed, even supporting our current population might prove a significant challenge.

In light of everything described above, we would be very well advised to restrict our population growth as much as possible, as soon as possible. Our ageing demographic profile – the “baby-boomer bulge” – represents an opportunity to do this in an organized and humane manner. We should not be desperately importing new mouths to feed in a vain attempt to either build more houses or support the baby boomer generation through their retirement. For the sake of our children’s future we should, instead, do what is necessary to cope with the passing of the ageing bulge using our own people. This will be difficult, but an informed Australia can accept and meet this challenge. Moreover, our children will be left with a far more robust and food-secure nation. The alternative, “Big Australia” is not really an alternative at all.

(Thanks to DK, JW and others for comments and assistance with figures.)