The Nature of Emus

There are no Emus (Dromaius novaehollandiae) in Robertson, and there are no truly wild Emus in Canberra, but there were Emus there when the first settlers arrived. That fact is documented in a book by my father, Steve Wilson, called "Birds of the ACT - two centuries of change" (published by the Canberra Ornithologists Group).

When Tidbinbilla Nature Reserve was first established, sometime in the 1970s, Emus were re-introduced to the area, to recognise the fact that they were originally in the area. There were occasional reports of wild Emus in the high plains country, very high in the Alps, during the 1980s. Anyway, some of the Emus of the Tidbinbilla area survived the devastating bushfires of January 2003, and are still roaming the sheep paddocks below the main area of the Reserve.

Emus are said to be extremely primitive birds, and along with the Cassowary, Ostriches, Rheas and the diminutive New Zealand Kiwi they are grouped together in a Order of birds called Ratites. All are flightless birds, with coarse feathers. They do not have a deep bone on their sternum where normal birds have their strong wing-beating muscles attached. (- for contrast, have a look at the chest bone of the next Chicken you consume).

From my point of view, I consider that Emus and other Ratites are in fact highly evolved birds, which have abandoned the power of flight. They do have wings, just remnant wings which are totally useless for flight. To me, it makes sense to regard these as obsolescent organs, remnants of formerly useful structures, which they no longer need.

The left wing of this Emu is clearly visible in the photo at left, just in front of the leg. It is hanging down below the line of the body.

Female Emus lay their eggs in autumn and winter, and the male then sits on the eggs, and broods the young, and raises them. This apparent "family group" might be a female (the larger bird) and a male, in the middle with two chicks from two years ago. Alternatively, it might be a male. with three chicks. I cannot tell, but I favour the first explanation, as the middle bird is showing some of the adult blue colouring on its neck. The only problem is that Emus are not sentimental birds, and do not tend to hang around in "family groups". Partly this is explaimed by the need of the female to be able to reproduce by laying large clutches (up to 15 eggs) of huge eggs, which is a great reproductive burden. To do this, she needs to be in peak physical condition.

So the Nature of Emus is something of a mystery.

The Nature of Wild Fire and Drought

The edges of Canberra and much of the Snowy Mountains (in both Victoria and New South Wales) were subjected to a huge and devastating Wild Fire in January 2003. For Canberra it was a specific day, January 18th, but the fire had been burning for several weeks in a contained area west of Canberra before then. Then, another branch of the fire spread south, through the Tidbinbilla Nature Reserve, and burnt up into the Snowy Mountains. At the same time, equally devastating fires were burning similar country in the Victorian Alps.

The foothills of the mountains were planted with Pinus radiata, which were totally destroyed, and hopefully will not be allowed to regrow.

There is a mythology in Australia, that it always rains after a big bushfire. I am here to tell you that it is not true.

After a fire, native trees recover according to their own methods of survival, which have developed according to patterns of evolution, over geological periods of time. Generally Eucalypts experience a total burrning of their oil-filled leaves, during a fire, but new growth occurs from dormant buds under the thick, protective bark of the tree. Generally! The tallest of the wet mountain Eucalypts, the "Mountain Ash", have lost this genetic survival strategy. They tend to die in fires. That is possibly because when a fire takes hold in their territory, of tall timber, and dense forest, the intensity of the fire is such that even the sap-wood of these huge trees is dried out and killed. Anyway, Mountain Ash generally rely on seedling regrowth after the fires.

The news is better for most other Eucalypt trees. They experience a sudden burst of new growth, and the forest quickly greens up again. Normally! This is where the presence of rain is important after a fire. Since the 2003 fires, the entire alpine region has continued in drought, so the burst of regrowth which followed the fires, dried out, and many trees died entirely. Those trees which did survive, have struggled on, severely damaged. And they are still waiting for rain.

The Baroomba Rocks at Tidbinbilla are a small cluster of huge granite boulders, each several times the size of a normal house. Big rocks, or a small mountain, you decide.

The thing is how bare they are now. These rocks are clearly visible from Canberra, some 40 Km away. The main reason is how bald they now are. There were forest trees all around them, and the rocks were moss-covered. Now the trees are barely alive, and the rock faces are bare. So, from Canberra, these rocks stand out as a pyramid shaped mountain, in front of the much larger Tidbinbilla Range in the background.

These rocks bear tribute to the need for rain in South-east Australia.

Today 62 % of NSW is declared in drought condition. And this very week, the Federal Government, (and I am ashamed to say - the NSW Government is supporting this idea) is proposing to sell the Snowy Mountains Hydro-Electric Scheme to private interests. God help this country run by Free Market Idealogues. One day we will remember that there is such a thing as an over-riding National Interest.