Kangaroos and carbon

Wherever people settle, decimation of local plants and animals often follows; but from time to time some native species thrive thanks to human activity – and it’s not always a good thing.

A great example of this is several species of Australia’s kangaroos. Kangaroos number somewhere around the 25 million mark according to the Kangaroo Industry Association. There are as many roos in Australia as there are people – probably more.

Even with human encroachment, these numbers are far higher than previous to European settlement due to the increased food and water supply generated by the activities of the sheep and cattle industry.

Prior to European settlement, major droughts may have killed off as much as 80% of the roo population in affected areas. As cruel and tragic as this sounds, it had an important benefit – alleviating the strain on native grasses and other plant life that kangaroos eat and allowing the native flora to regenerate so it could again sustain a reasonably sized roo population.

A while back I published an item on  kangaroos perhaps holding answers to help address global warming as unlike livestock, kangaroos don’t fart methane; which is another potent greenhouse gas.

However, I read an article today that reports a negative impact of large numbers of kangaroos in grazing areas in regard to carbon sequestration and greenhouse gas production.

It seems that coupled with their numbers, the way kangaroos forage reduces the quality of the feed available to other grazing animals, which translates to more methane emissions when livestock graze in affected areas. As kangaroos prefer new growth, their eating habits also shut down grass growth and prevents the transfer of carbon from the atmosphere to the soil.

I’m not pointing the finger at the kangaroo as the root cause of the issue is still very much human related, but it’s a fascinating topic, one you can read more about here.

I was always under the impression that unlike livestock, the way roos browsed allowed for plant regrowth as they don’t eat down to the ground; but the photo in the article I linked to above seems to indicate otherwise. I guess it’s all down to numbers – too much of anything in too small an area is bound to cause problems.

Still, it seems to me that if we do have to have a livestock industry, one based on an animal evolved for Australian conditions makes more sense. After all, in a grazing enterprise the grass is going to get eaten anyway, so why not turn the problem into the solution. But that isn’t likely to happen and I do understand the author’s point of needing to be able to control when the grass is consumed in order to reduce methane emissions from livestock and to improve soil carbon levels. Kangaroos don’t really respect standard stock fences -I’ve seen them jump a 5 foot fence from a standing start. Higher fences perhaps? Perhaps, but that comes at a huge cost and would create other environmental problems. Realistically, it boils down to farmers being permitted to responsibly cull the critters on an ongoing basis.

I love kangaroos and I have a few of them on my property. I have never hunted them and never would unless it was a matter of survival or they reached plague proportions. Even in the latter scenario, special licenses are required to cull kangaroos.

I feel sorry for the roos during the dry spells and I try to make a small amount of water available to keep some of them going. However, I’m now reconsidering this – it’s just another instance I’ve found where I believed I was helping nature, but may actually be working against it.


Fascinating kangaroo facts