Rebuilding Australia: How reintroductions and introduced species could help save a continent's wildlife

I am not from Australia, so I have no doubts that whatever I say will be dismissed by at least some people as just the ramblings of an uninformed foreigner. They may be right, but I would like to think that at least some subjects can be mostly, though not entirely, learned from reading and thinking. I have written about Australia before, and in fact I have something of a fascination with the continent for a variety of reasons. One is the most obvious; from a wildlife perspective, Australia is unlike any other continent on present day Earth. The marsupial faunas that (used to) dominate there are the last remaining on the planet, after South America's collision with North America essentially ended the age of marsupials there, and the general cooling of the global climate wiped them out on most continents. In this respect, it offers us something of a look back at earlier times, and gives us a window into the past diversity that marsupials once enjoyed across so much of the world. There is another reason for my fascination with Australia however. It is the only tropical first world country, and certainly the least densely populated one. The great majority of Australia is still wilderness in one form or another. A rich country with magnitudes of uncultivated wilderness and an iconic endemic fauna, that sounds like a great thing, doesn't it? Most of the problems facing wildlife in other tropical countries are at least partly a result of the widespread poverty and corruption in said countries, and while Australia cannot necessarily be completely cleared of the later, it is certainly nowhere near as extreme as in most countries with similar climatic conditions and quantities of wilderness. You would think that the Land Down Under would be an ideal place for nature, a country with a great fauna wealthy enough to protect it. So why is everything going so horribly?

With 11% of its mammalian fauna extinct within just the last few centuries, it has the highest rate of mammal extinctions in the world. On top of that, 15% of the remaining species are also endangered, with more yet more on the verge of being so. All in all, things are not going well for Australia's mammals. The typical explanation for this is that, as an isolated island continent, Australia's endemics are especially vulnerable to introduced species. It was the foxes, goats, and horses that did it, or so the story goes. In this post I will be arguing against that prevailing idea, and continuing on my previous post on Australia in arguing that invasive species are merely a symptom of a wider problem, and that a few of the introductions may in fact be part of the solution.

Australia: Land of marsupials, especially extinct ones.

Alien species and the future ecology of Australia

First off, the next post will be about prehistory, I promise, this is the last conservation related post for a while. With that said, buckle in, as this is going to be a long one.

Species disperse, this is an universally accepted part of ecology and evolution. Eventually animals will spread from one area to another, and if the conditions in this new habitat are different enough that they favor unique adaptations, evolution will occur, possibly resulting in the creation of a new subspecies. When animals naturally disperse, we tend not to have a problem with it, at least in most cases. Take for instance the Cattle egret. This small Heron has rapidly spread to colonize most of the world, while even just a century ago it was mostly restricted to Africa. This seems to have been completely by its own doing, and thus we have allowed it. Another example of this is the Turtle dove, which rapidly spread from western Asia to most of Europe within a few decades, though it is now declining again.

The Cattle egret, conqueror of the world

The world that we forgot

Humans are an inherently short sighted species. We do not think too far into the future, and rarely gaze much further back than our youth. At most, the average person thinks a few decades forward, and a century back, anything beyond that is largely forgotten, or ignored. For conservationists protecting nature, this cone of vision is slightly less narrow, often looking an entire century forward, and sometimes upwards of 500 years back. This allows them to view the general trends these last few centuries have experienced. But it is still a narrow view, and still does not offer one crucial thing; Perspective. Most conservation efforts focus either on preserving areas as they are today, or turning them back at most a few hundred years. Often the time just before the industrial revolution is used as a target, an ideal. In this post I will discuss why to properly conserve nature, one must look much further back, and how this lack of perspective and vision is choking nature today.

The Cairngorms of eastern Scotland

Lizard Kings: The giant Monitors of prehistoric Australasia

Today, the Komodo dragon is quite a well known animal. As the largest lizard in the world, it carries a prestigious title, and it is indeed an impressive creature. The Komodo dragon is however only one part of a greater puzzle, that being the giant Monitor lizards that once dominated much of Australasia. Not much is known of these enigmatic animals, but the bits and pieces we do have seem to reveal what was previously a widespread and successful group, now mostly extinct.

The most famous of the giant Monitors is obviously Megalania, a huge lizard that inhabited southern Australia up until the arrival of humans, when it was wiped out in the Anthropogenic-extinction. Known only from fairly incomplete remains, despite being a very recent animal, Megalania has been the subject of much debate, chiefly over its size. Original estimates from when it was first discovered placed it at 7 meters in length, what that would have made it a truly enormous animal, but in 2002, Zoologist Stephen Wroe found it to be a great deal smaller, at only 4.5 meters in length. This was again changed in 2009, when Wroe himself along with other researchers upsized it to 5.5 meters. In truth, we have no idea how large Megalania really was, since we do not know of its proportions. Ralph Molnar said in 2004 that if it's proportions were like those of a Komodo dragon, it would have been 7 meters long, while if they were similar to a Lace monitor, it would be upwards of 8.

Varanus priscus, by Vlad Konstantinov