A US biologist noticed that in the chaparral canyons outside San Diego, a greater diversity of birds survived where coyotes were present.

Why?

It was discovered that more coyotes meant fewer cats, which meant more birds. The coyotes were eating cats and foxes and acting as a control. A study confirmed that one in five coyote scats contained domestic cat.

Those coyotes must be darned quick.

Anyway, scientists are learning what is termed "mesopredator release" in areas without native predators gives cats, dogs and foxes the ability to flourish unchecked.

This is very important - indigenous predators not only control prey, but other predators, and by doing so regulate species with which they never directly interact. Makes perfect sense.

We have very few furry four-legged native predators here in Australia as we've wiped most of them out. The dingo is the closest thing we have to a wolf or coyote; but even the dingo is a relative newcomer, thought to have been brought here about 15,000 years ago.

Still, the dingo is as good as native and like the coyote and the wolf, it is considered to play an important role in our various ecosystems. The dingo has been much maligned; not helped by the Azaria Chamberlain case some years ago.

However, long before the infamous "a dingo's got my baby" was screamed, the war on the dingo had been declared in this country.

Back in the 1800's, the world's longest fence was constructed as a means of excluding dingoes (originally meant for rabbits) from a huge chunk of Australia as they were taking their toll on livestock. The fence is an incredible 5,614 km (3,488 mi) long.

The fence has worked well generally, but there has been a price to pay.

For example, dingoes used to be fairly common where I have my block of land and without their presence, the feral goat population has flourished.

The previous owner of my block and the surrounding allotments used to pull 400 feral goats out of the area each year! Before some controls were carried out a year or so ago, I was seeing flocks of over 50 animals on my patch and they were doing a heck of a lot of damage. I've also spotted a couple of feral cats and foxes in the area and wild dogs are known to roam the region.

Dingoes also help to keep the kangaroo population down. As cute as kangaroos are, they are now in numbers far exceeding pre-European settlement.

Nature never ceases to fascinate me in how it works - and just how easy it is to upset the balance. "Re-wilding" could help in the battle against what is termed the Sixth Great Extinction; a phenomenon not some way off in the future, but happening right now.

Unfortunately, I can never see the dingo and graziers living peacefully side-by-side.

As individuals, we may not be able to play a direct role in "re-wilding", but we can all do our bit by ensuring our own pets don't stray and prey on native animals.

Related:

Greening your cat
Reducing your pet's environmental paw print.
Recycled pets