The US based 'zero population growth' movement was never based on empirical science, but personal preferences, linking negative or proxy issues e.g. environment, with 'non-European immigrants', no surprise due to 'white nativist' influences.
Keep in mind the UN definition as used by Australia changed in 2006 to include temporaries, in addition to new permanents, via the NOM net overseas migration which is balance between arrivals/departures of ALL travellers. Accordingly this has inflated the headline estimated resident population (which is then spruiked negatively for maximum impact), and mostly reflects international students, backpackers, 457 workers, NZ'ers and dependents.
Further, one of the increasingly significant drivers of population growth in Australia and the rest of the world is neither fertility nor immigration, but longevity through better health care and education leading to an ageing population that needs to be supported physically and through working tax base.
Rather than increase the permanent migration program Australia has come to reply upon temps who can work, with no or limited access to future permanent residency and citizenship, who in fact lower the per capita debt.
Regarding statistics, like 'population' and 'immigration' the definitions have been egregiously conflated and confused to induce inflation of data for more impact in media.
For an expert view on international population growth, human development and statistics Professor Hans Rosling is the acknowledged expert, and concurs with enviornmental scientists etc., outside Australia, that the supposed issue is not scary and in fact a myth: 'Don't panic: the facts about population' http://www.gapminder.org/videos/dont-panic-the-facts-about-population/
Viewpoints or theories presented by 'experts' about demography, 'population', 'immigration' etc. in Australian media seem more related to the beliefs and attitudes of good old boys from the deep south of the USA.... unfortunately it's not science.
For more info about population, immigration, international education and human development visit AIEC Europe http://aiec.hu/en/international-education-immigration-development-population-news