The marsupials have the potential to be the Prius of the nation's farmlands.

A scientific paper in the international journal Conservation Letters reports that expanding the kangaroo industry would significantly decrease greenhouse gases.

It has long been known that hard-hoofed sheep and cattle have caused land degradation across the continent.

But only recently have scientists become aware of the damage done by large methane emissions of traditional farm stock.

The paper's lead author, George Wilson, says kangaroos could help cut greenhouse gas emissions.

Dr Wilson is involved with the University of NSW's Future of Australian Terrestrial Ecosystems project and also runs the consultancy company Australian Wildlife Services.

He and his co-author, Melanie Edwards, say a proposal to reduce sheep and cattle numbers on the rangelands by 30pc should be considered.

Sheep and cattle constitute 11pc of Australia's total greenhouse gas emissions.

Kangaroos, however, produce relatively little methane because they are not ruminants.

"Reducing cattle and sheep populations and increasing the kangaroo population on the rangelands to 175 million to produce the same amount of meat by 2020 would lower [greenhouse gas emissions] by 16 megatonnes, or 3pc of Australia's total emissions," the paper says.

The authors argue the increase in kangaroo populations from 34 million to 175 million would be made possible by the decrease in sheep and cattle numbers.

The paper says the carbon dioxide equivalents saved from 2007 to 2020 would be worth $655 million.

"If a national [emissions trading scheme] requires livestock owners to purchase carbon permits to remain with cattle and sheep, landholders would have a stronger incentive to use kangaroo as low-emission meat."

In addition, the authors say, management costs would be lower - less fences or yards, internal or external parasite control, shearing, crutching, branding, dehorning or castrating.

Dr Wilson acknowledges a bigger kangaroo industry is a "hot topic" because it involves big changes in established industries.

Many farmers also regard kangaroos as pests.

Also confronting an expansion of the industry is that many environmentalists and animal rights groups regard kangaroos as an icon and as a native species that should be protected.