Seasonally ploughing and harvesting crops will mash up a few moles, slice through a burrow of field mice and crush any ground-nesting bird chicks. Far more significant, however, is the creation of the field in the first place: an act that replaces entire ecosystems, along with all their animal inhabitants.

In the United States, under 3 percent of municipal food waste - so that's the food scraps that goes into people's garbage cans - actually gets recycled. If you go to a place like South Korea, the exact reverse is the case. It's about 3 percent that doesn't get recycled.

In Kenya, where there isn't the luxury of feeding grains to animals, livestock yield more calories than they consume because they are fattened on grass and agricultural by-products inedible to humans.

We domesticated pigs to turn food waste back into food. And yet, in Europe, that practice has become illegal since 2001 as a result of the foot-and-mouth outbreak. It's unscientific. It's unnecessary. If you cook food for pigs, just as if you cook food for humans, it is rendered safe. It's also a massive saving of resources.

Cities are where the climate battle will be won or lost.

I enjoy a four-seasonal climate and wide-open spaces, so being on an island 2,500 miles into the South Pacific made me feel a little claustrophobic.

It is undeniable that the looming environmental crisis is partly the consequence of population growth.

Australia and New Zealand have traditionally shared very close links, yet there are things that set us apart and make us unique - Australia's wildlife experience being one of them.