BORIS BURDA: How Australians Tamed Animal Immigrants
Photo by Joey Csunyo on Unsplash
ATTENTION — QUESTION!
The famous zoologist Konrad Lorenz noted that by the time Australia was discovered by Europeans, the overwhelming majority of Australian mammals were marsupials. The only exceptions were the dingo, several species of bats, and one more species. Which one?
ATTENTION — CORRECT ANSWER!
Homo sapiens, of course — people were already living in Australia at that time.
A UNIQUE COMMUNITY
The smallest continent — recognized as such last of all, even after Antarctica (remember how in In Search of the Castaways Lord Glenarvan says that Australia is nothing more than an island, and Paganel clarifies that many geographers already call it a continent?) — is unique in many ways, including its wildlife.
It was formed millions of years ago, when Australia, South America, and Antarctica made up a single ancient landmass. Marsupial mammals have survived only there, with the exception of the opossums in the Americas; in Australia, however, there are hundreds of species, because the ocean generally prevented their more adaptable placental competitors from arriving.
Some marsupials disappeared from the Earth back in prehistoric times. Even in Australia, neither the two-ton diprotodons — marsupial hippos — nor the ton-weight palorchestes, marsupial tapirs, nor the marsupial lion that hunted these giants, nor the three-meter kangaroo Procoptodon managed to survive, as large species adapt more slowly to change.
The greatest danger to Australia’s wildlife began over 60,000 years ago, when the most adaptable and aggressive creature to date — humans — arrived on the continent from Southeast Asia. For them, no malice was even necessary to wipe out a species (as in the United States with the bison) — they could destroy it casually, without even realizing it.
NO LONGER JUST WILD
Beware the bull from the front, the horse from behind, and a human from all sides: if they don’t harm you directly, they’ll bring something harmful along. About 5–6 thousand years ago, settlers from Asia brought their dogs here, but failed to keep watch over them, and the dogs went feral again. Soon they spread across most of Australia and acquired a special name — the wild dogs called dingoes.
We tend to think of dingoes with a certain warmth, mainly associating them with Ruvim Fraerman’s beloved childhood story The Wild Dog Dingo, or the Tale of First Love. But literature is one thing, and life is quite another. As a non-native species in Australia, dingoes did not fit into the existing food chains and began creating their own.
Like all dogs, dingoes can hunt in packs, which, firstly, made them dangerous to all of Australia’s wildlife and, secondly, gave them a major competitive advantage over marsupial predators, which began to die out. Dingoes didn’t stop at wild animals — they also started eating livestock, becoming serious pests for Australian farmers.
It was no longer possible to simply shoot enough of these intelligent and strong animals, so farmers took a monumental measure to reduce the damage dingoes caused. They built a massive fence, not much smaller than the Great Wall of China, to keep them out of the best pasturelands. Maintaining, patrolling, and constantly repairing it costs $15,000,000 a year.
And since dingoes could go feral again, could they also be tamed again? It turned out they could. In the 1980s, tamed dingoes became fashionable in Europe and America. In France and Spain, they take part and win at dog shows, and in Switzerland an official breed standard was even developed. A dog is a dog — only it doesn’t bark, it howls.
The Aboriginal people also tamed dingoes, but unlike Europeans, they didn’t use them for hunting, and unlike Koreans, they didn’t eat them. They did teach them to guard, but beyond that, they found a new, rather unusual way to benefit from their presence. Do you know what Aboriginal people call a cold night? “A five-dog night.” Yes — tamed dingoes are still used by them as living heaters.
NOT JUST VALUABLE FUR
Another dangerous assault on Australia’s nature occurred in the 19th century, and the locals even blame a specific person for it — though, of course, he was unlikely to have been the only one. The fact remains that in 1859, an Englishman named Tom Austin, who had moved to Australia, grew bored without the hunting he was used to and persuaded his nephew to bring him 24 rabbits from England.
A doe rabbit can breed up to seven times a year, producing up to 12 kits at a time — so you can imagine how little time it took for rabbits to overrun Australia. Back in the 19th century, killing a rabbit was punishable by a fine, while today, in Queensland, anyone who keeps one of these animals faces a $40,000 fine. The only exception is for magicians — after all, who else would they pull out of a hat?
By devouring grass, rabbits not only starved local marsupials — by stripping away the topsoil, they turned land into desert. Another problem was the growing number of sheep breaking their legs after stepping into rabbit burrows. Farmer Bill MacDonald recalled that there were so many rabbits it seemed as if the ground itself was moving. And they kept breeding… like rabbits!
As with dingoes, attempts were made to fence the pests out. But that was useless — they could dig under any fence. So a weapon of mass destruction had to be used against them, since they themselves were a kind of WMD. In 1950, the troublesome pests were infected with the viral disease myxomatosis, which at the time had a 99% mortality rate.
At first, the results were excellent — in just a couple of years, Australia’s 600-million-strong rabbit army shrank to 100 million. But the survivors passed on their resistance to the virus to their offspring, and the method’s effectiveness dropped. Still, things eased somewhat, and rabbits are no longer the terrifying scourge they once were.
And this works not only on rabbits. More recently, another biological threat — feral cats, which have already wiped out more than one species of native fauna — was reduced in number with a poison called Curiosity. Why that name? It comes from the English proverb “Curiosity killed the cat.”
HELP FROM AN EGYPTIAN DEITY
Yet another problem for Australia’s nature was brought in by humans quite deliberately — livestock, mostly cattle and sheep. There’s plenty of grass in Australia to feed huge herds. So what’s the issue? The problem is that the animals digest this grass and then cover Australian fields with—you can guess what—so thoroughly that nothing else can grow there.
But what’s so delicate about Australian soil? Don’t enormous herds roam the steppes of Eurasia, the savannas of the Americas, and the African veld without causing the land to stop producing grass? Just imagine the biological impact where a herd of elephants has grazed! And yet the grass still grows there without trouble.
The explanation is simple! Australian insects that process such waste turned out to be rather weak. They could cope with the modest biological material left by native fauna, but they were no match for the aftermath of tens of thousands of grazing sheep. In Africa, by contrast, even elephants don’t cause major problems — so why is Australia so unlucky?
It turns out that in Africa this work is handled by far more efficient cleaners of what the local livestock drops — enough to cope even with elephants! Africa, after all, is the birthplace of the sacred scarabs — dung beetles that the ancient Egyptians revered. And with good reason — they could keep things tidy even after elephants!
This gave Australian biologists a simple and elegant solution. They brought several species of these very same sacred scarabs to Australia. The climate of Morocco, where they were collected, is similar to Australia’s, and the beetles immediately set to work. Now, Australian fields can grow grass again instead of… well, what used to be there.
Thus, Australian scientists are correcting the unwise actions of their predecessors, restoring biological balance in a way that requires neither huge effort nor excessive cost, because it sustains itself. This gives hope for preserving the unique biodiversity of Australia’s nature — for there’s no time left to waste.
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