Feral foxes in Australia

From tame English forest
Outfoxed by the hounds
The captive is shipped
Off to far southern bounds

In wild Aussie bushland
He hides from the hounds
And preys on the rabbit
That newly abounds

He soon finds a mate
And extinction he brings
To the wildlife estate
Where he is now feral king

Riding to the hounds was very popular among the rich and famous in England in the first half of the 19^th century. Fox hounds, originally developed in the 16^th Century by crossing grey-hounds, fox-terriers and bulldogs, became very common and they made their way to the colonies with the hunt-mad Anglophile colonists.

Fox hunting was an integral part of colonial social status and wealthy colonists invariably had their stable of well bred horses and packs of fox-hounds to go with their fine clothes, large houses and teams of servants. In the early days the Australian colonists had to make do with kangaroos, dingoes and the occasional “bag-fox” imported directly from England whilst they tried their hardest to establish the fox in Australia. There is documented evidence of foxes being introduced into Van Dieman’s Land in 1833 and into the Port Phillip District of NSW (now Victoria) in 1845. The Governor of NSW, Sir Charles Fitzroy, who was the Master of the Sydney Hunt, received two dog foxes from England in 1855 and soon released one:

After being given just a few days to recover from their long sea voyage; one fox was released from a cage at Randwick Heights. Bewildered at first release the imported fox “crouched and crawled forward slowly, looking about him….he raised himself suddenly and made for thick scrub. The hounds were all in leash and the horsemen stationed on a knoll a little way off. The fox kept to a ridge past Maroubra Bay and then turned inland into more open country. He came out on a large open plain and tried to turn back, but the hounds met him and tore him to pieces.

It appears that none of the early importations were successful in establishing the fox in Australia. That didn’t happen until 1871 when a local physician and “acclimatisation” advocate from Ballarat, Dr. King, released a dog fox and two vixens 12 miles west of Ballarat. At about the same time Thomas Chernside released “several foxes” on his 90,000 acre Werribee Park Estate at Point Cook near Melbourne. By this time rabbits had become well established in the area and with this new and abundant food source foxes quickly become established. Wild foxes were sighted near Ballarat in 1874, Laverton in 1878, Corio Bay in 1880 and Bendigo in 1886. By 1990 they had colonised 13,000 square kilometres of Victoria and had become a significant agricultural pest. They followed the rabbit across the Nullarbor and were first sighted at Kalgoorlie in 1917. So it was ultimately all about timing. The newly established rabbit population was expanding rapidly at just the right time to provide sufficient food to establish the fox which also preyed on native species.

Foxes today occupy the whole of sub-tropical Australia and number about 7.2 million animals. They consume an estimated 190 million native birds a year and are the single greatest agent of mammal extinction in Australia with Woylies, Numbats, Bandicoots and other small marsupials being particulalry vulnerable. Tasmania fortunately remains fox free despite many introduction attempts. This is probably due to the presence of the Tasmanian Devil and its ability to eat fox cubs. In recent times, in an act of almost incomprehensible environmental vandalism, there has been a further fox introduction into Tasmania. This time with Devils on the wane due to the facial tumour disease they may get a foothold despite attempts to eradicate them.

Many thanks to http://tasmaniantimes.com/index.php/article/hunting-foxes which presents a detailed history of fox introduction into Australia.

Splendid Fairy Wren

Splendid Splendid Wrens
Glorious to see
They lift our spirits high
And are pretty as can be

They keep the insects down
And so protect the trees
We wouldn’t have a forest
If not for such as these

So protect the understory
Of the forest near your home
And you may see the glory
Of the Blue Wrens as they roam

The Splendid Fairy Wren is commonly called the Blue Wren in Western Australia and it is spectacular. They are a socially monogamous but sexually promiscuous species and the male in his electric blue breeding plumage is magnificent. If you are very lucky you may see him presenting bright pink or purple petals to his partner or girlfriend. You are unlikely to see them unless you have the thick bushy understory vegetation that they favour and they are becoming increasingly uncommon as the urban sprawl engulfs more and more bush-land. But just as the wren needs the bushland so does the bushland need the wren. Parkland clearing is becoming very common in Western Australia. People appreciate the large shady trees but they also like the look of the grassy fields which can also feed their horses and other grass-eating pets. What they don’t understand though is that this can spell the doom for the trees. The dead and dying Flooded Gums through the river valleys near Perth are often heavily infested with leaf eating psyillid insects (Lerps) that were once effectively controlled by Blue Wrens and other insect feeding birds that inhabited the now absent understory. We upset the ecological balance at our peril! So do yourself and your bushland a favour and retain the shrubby understory and you may be rewarded with a healthy forest and the uplifting sight of the Splendid Blue Wren.

Nature in the balance

Nature is in crisis
In the sea and on the land
As species disappear
With a sweep of human hand

We seek to find a balance
And we try to lend a hand
But human greed is boundless
And we use up all the land

We like to live in comfort
But we fail to understand
That if we lose our wild places
We will be truly damned

The key question of our age would appear to be: How much nature can we afford to keep? How much land do we need for food production and habitation and, what wild places should be preserved? We, who have forever been subject to the laws of nature are now in control and we decide what survives and what can be sacrificed for the greater good. But we delude ourselves. The key question of our age is really: What can we afford to lose; and the question will soon be: What can we save?

We may think that we are in charge, and as we increasingly concentrate in our large concrete cities we can easily forget that humanity is intrinsically woven into the web of life. But the day of reckoning is nigh. With an extinction rate 20,000 times the background rate we are in territory not seen on the planet for 65 million years. But this time it is being caused by us and not by a large asteroid impact. And as we destroy the cycles of nature that sustain life in our fragile biosphere we inexorably march towards a collapse of our agricultural systems, rampant disease and foul air and drinking water. We can avert this crisis but we need greater consideration of nature in our decision making.

Nature needs a stronger voice at the table if we are to prevent greed and short-term self interest destroying our society and our species. Who, like the Lorax, will speak for the trees who have no voice of their own? Humanity has been a poor steward so far, and our best hope is to wake the Lorax in our midst and work for a sustainable future.

Red-Tailed Black Cockatoos

Piercing karak squawking
And a brilliant flash of red
And the marri nuts are falling
From the branches overhead

Red and black and welcome
They have travelled far from south
Seeking remnant marri
To feed their hungry mouths

Returning to the Moondyne
After many years
Forced to travel further
As their food source disappears

It’s been years since the Red-tailed Black Cockatoos were in the Moondyne and this year they are everywhere. When I first saw the falling marri nuts and the brilliant red flash of the spreading tail feathers I could scarcely believe it. But there they were in their hundreds, feasting on the marri nuts, while the forest rang with their piercing shrieks. But why are they back after all this time? This was the edge of their range 100 years ago but they have been gone for decades. As their once great population fell due to habitat loss to agriculture they retreated to their forest heartland far to the south and were rarely seen in their former haunts.  But now they are back and amidst the thrill of seeing them is a deep sense of foreboding. Something has changed!

There are five sub-species of Red-Tailed Black Cockatoos in Australia. The Forest Red-tailed Black-Cockatoo (Calyptorhynchus banksii naso) is found in the southwest corner of Western Australia between Perth and Albany and is classified as Near Threatened. It can be differentiated from the other sub-species by its large bill which is useful for getting seed out of the woody nuts of the Marri (Corymbia calophylla) which is its favorite food.  The population of this sub-species, similar to other sub-species of Red-Tailed Black Cockatoos, continues to fall. It’s return to the margins of its ancient haunts can only mean that conditions in the heartland have become more difficult or conditions in the margins more favorable. Hopefully it is the latter and there is certainly a bumper crop of Marri seed this year. The other thing that is odd is that Carnaby’s White-tailed Black Cockatoo ,which are generally on our property at this time of year, are nowhere to be seen. So we have a great cocky mystery. The Red-tails are here and the White-tails are somewhere else.  Hopefully they are all happy where-ever they are. And while I love to see them I can’t help hoping that the patterns soon return to normal. Major shifts in long-term population distributions are rarely a good thing and it looks to me that something at the moment is out of balance.

Climate Change Sceptics

You won’t find climate sceptics
Near the thinning ice
Or on low island atolls
Vanished in a trice

The dire real world picture
That should be plain to see
Is sadly out of focus
When filtered through TV

Comfortable and powerful
Men in caves of steel
Decree the truth illusion
And climate change not real

I am always interested when apparently educated and intelligent people deny the reality of climate change.  I listen carefully to what they say and usually discover that they are not particularly well informed.  They often believe what they have read in the newspaper, seen on TV or even read on blogs and with no real world context have accepted opinion as fact. But being well informed is not a prerequisite to having a strong opinion. When you work in a central city office with regulated heat and purchase your food from a supermarket it is unsurprising that your real world view will be blurred.

On the other side of the ledger are those on the front line. You won’t find climate change sceptics amongst the marine biologists and climate scientists who are daily confronted with the reality of massive changes in climate and ecology and particularly with respect to marine ecology which is changing rapidly. You also won’t find too many climate change sceptics among the Pacific islanders who are watching their atolls disappear beneath the waves or the Inuit in their rapidly warming Arctic homes.  It is ironic that the opinion of native peoples, who are such careful observers of the weather, is of such little worth in comparison with the opinion of highly articulate but often profoundly ignorant men of power in their caves of steel.

Toads of Karragarra

Today on Karragarra
When walking down the road
I saw a kookaburra
Ignore a dead cane toad

Who was it that taught him
That it's bad to eat a toad
Looking fresh and tasty
Squashed upon the road

Perhaps when he was younger
He ate a little toad
And never has forgotten
That bitter poison load

There is plenty of evidence of kookaburras dying after eating cane toads but it looks like they are learning. It may be that mother kookaburras are teaching their young to avoid them but it is also likely that they have become ill after getting a sub-lethal dose from a small toad and avoid them ever after.  Let’s hope they continue to learn.

Toads are very destructive and not just because they poison the large predators. They breed like crazy and consume the insect and other resources needed by other wildlife. So the toads become fat and plentiful while everything else declines. They are bad news!

They are almost impossible to eradicate and it is easy to exacerbate the problem. We live on Karragarra Island on Moreton Bay. It is a long skinny ridge of an island flanked with mangroves and has little of the natural surface water necessary for toads to breed.  So how come it is teeming with toads? I discovered part of the answer on the western end of the island a few weeks ago. Someone had excavated a shallow depression, presumably as a source of fill for the adjacent road and rainwater had pooled in the depression. The shallow pond was teeming with distinctive jet black toad tadpoles and countless baby toads were swarming through the leafy surrounds and heading for the forest. With a large female toad capable of laying 30,000 to 40,000 eggs at a sitting it is a dire situation.  

The carbon ice-age cycle

The drifting continents
Clash and pull apart
As the pulsing polar ice-caps
Beat on like a heart

Expanding as the carbon drops
And shrinking as it rises
This carbon linked great cycle
Is one of earth’s surprises

Driven by great algal blooms
That peak in times of cold
And die away to little
As the seas grow hot and old

The earth and its biosphere are intimately linked. The ancient dance of ice-ages and interglacial warmth cycle on and on in response to Milankovich orbital cycles or the episodic rising and falling of atmospheric carbon dioxide levels.  Sharp falls in atmospheric carbon dioxide levels can occur when massive oceanic algal blooms suck up billions of tonnes of CO₂ . This could occur for many reasons including continental drift modifying ocean currents, volcanic eruptions or fractures in the earth’s crust releasing billions of tonnes of natural gas.  This in turn can trigger an ice-age which reinforces itself with the albedo of marching glaciers and is accompanied by dramatic drops in sea-level. But as the nutrients in the ocean slowly deplete the algal blooms reduce and atmospheric carbon-dioxide levels start to rise. The world begins to warm and rain returns to shrinking drought stricken continents reducing the volume of iron-rich dust settling on the oceans.  The oceans become clearer as the continental vegetation flourishes and the ice-caps retreat.

 The massive release of carbon from the burning of billions of tonnes of fossil fuel by our industrial world is, unfortunately for us occurring at and intensifying the hot part of the cycle. To a large extent the rapidity of the current rise is uncharted territory. It may not, as the geologists tend to argue, make too much difference in the longer term but the short term impact if left unmitigated will be profound and include both mass extinction of species and the potential collapse of our civilisation.  Time will tell if we, like our ancestors who repeatedly abandoned and reinhabited places like the Unite Kingdom through the ice-ages, can also adapt.  We probably can but there won’t be many of us left.

But we do have the option of mitigating the degree of global warming by reducing our emissions and we also have the option of artificially triggering oceanic algal blooms through the addition of iron to upwelling zones to reduce atmospheric CO₂ levels.  We have to be careful before launching global bioengineering initiatives as the consequences of this are not fully predictable but it is something which should be looked at and business as usual no longer an option.

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