Sunday, 25 September 2016

Tirari Desert - Part 1


Followers of this blog may, after some 115 posts containing bird photos, be surprised to find no bird photos in this post, not one. However, Tirari Desert - Part 2 will contain bird photos from the area covered by Part 1.

On our return trip from the Top End we came south from the Savannah Way (Gulf Country) in far NW Queensland down through Lawn Hill, Mt Isa, Boulia, Birdsville and then down the Birdsville Track to Marree.  We continued south down the west side of the Flinders Ranges skirting the bottom end of the Flinders before finally heading East and home to Eastern Victoria. The north-south section of this route follows a direct line from the Gulf of Carpentaria to Spencer Gulf in South Australia.

The 517km Birdsville Track runs north-south and passes through the Sturt Stoney Desert at the top end, the Strzelecki Desert and along the Eastern edge of the Tirari Desert. The Track crosses flood plains, gibber plains, sand dune country and a low range of hills just north of Mungerannie (a cattle station homestead offering camping and fuel etc) and further south, the famous Cooper Creek. The Track is a good earth road these days however it can be closed and impassable after even relatively small amounts of rain.

Along the Birdsville Track we did a short side trip up the southern end of the Inside Track to look at the bottom end of the Goyder Lagoon - a huge floodplain of the Diamantina River. The Inside Track crosses an elevated gibber plain before abruptly dropping down to the flood plain where access via the track ended in flooded lignum – the Inside Track is often closed due to flooding. The Goyder Lagoon is a designated Important Bird Area (IBA) – for IBA details see:

Crossing a gibber plain on the Inside Track heading to the south end of the Goyder Lagoon.

The Goyder Lagoon when flooded, as it is now, is more or less inaccessible, so after a good look around we headed back to the Birdsville Track.

End of the road – Goyder Lagoon – the track continues north through the lignum.

While our main objective was to head home, we planned to spend a few days in the Tirari Desert on our way down the Birdsville Track. Many will not have heard of the Tirari Desert or know much about it, so keep reading and you will soon find out.

The following photo is from Google Maps with satellite images turned on. It shows a big-picture image of the area where the Tirari Desert is located. Down the right hand side (East side) of the photo, the Birdsville Track can be seen in yellow. The Warburton Creek snakes across the top middle half of the image joining the Macumba River from the west before turning south to enter the top end of Kati Thanda (Lake Eyre North) which can be seen at the bottom left half of the image.  The Tirari Desert is mostly a sand dune desert bounded by the Birdsville Track in the East (the Strzelecki Desert lies to the East of the Birdsville Track), Simpson Desert to the North and Kati Thanda on the West side. Another feature visible in the photo are the multitude of ephemeral lakes and the so called parallel sand dunes.



The Lake Eyre Basin is a truly vast and awesome area, with a huge variety of magnificent landscapes and a complex flora and fauna adapted to living in harsh desert environments. The Lake Eyre Basin, and more widely Central Australia, like infinity, is truly hard - even impossible, for the human mind to encompass. I often spend time viewing these areas via the satellite images on Google Maps to try and get a feel for the larger landscape that I plan to visit or that I have already experienced on our travels at ground level. I have included just a few snapshots (from space) of the area in and around the Tirari Desert. A few of the images remind me of some John Olsen paintings!

The range of hills just north of Mungerannie.

We camped on Warburton Creek on Cowarie Station and on Kalamurina Sanctuary in the Tirari Desert. The access road/track to Cowarie and Kalamurina heads NW from the Birdsville Track just north of Mungerannie.

Our camp site on Cowarie Station lies near the centre of this photo – the watercourse is Warburton Creek (formed upstream by the joining of Eyre Creek and the Diamantina River).

The Warburton River at Cowarie Station camping area. There was a good flow heading to Lake Eyre.

As for many of the Eyre Basin water courses the fringing vegetation is dominated by Coolabah (Eucalyptus coolabah) and Tangled Lignum (Muehlenbeckia florulenta). There are very few larger trees beyond the riparian strip so there is naturally a concentration of bird and other animal species along water courses. The old Coolabahs provide much needed nesting opportunities in a desert with few trees.

Sand dunes dominate the Tirari Desert.

The origin of the sand dunes is fascinating. Floods wash sand, silt and clay down from the vast catchment area (which extends from South Australia into the Northern Territory and Queensland) into Lake Eyre. When the Lake dries out strong winds blow the sediments out of the Lake bed into the surrounding country where dunes are formed. If this was not the case Lake Eyre would have filled with sediment thousands of years ago.

Note: The wind can be very strong and persistent across much of outback South Australia. The old saying “the crows fly backwards in South Australia” is well earned.

Warburton Creek meanders across what was probably once the bed of a Pleistocene mega-lake named Lake Dieri after the tribal name of Aborigines that once lived around Lake Eyre.
 
The Warburton’s course has been shaped by drifting sand dunes and other less discernable geomorphic features, ancient processes and a very long history - though relatively recent in terms of the geological time scale.

A sweeping bend of the Warburton closer to its discharge into Lake Eyre North.

In flat country, drainage lines become complex often with multiple channels and floods create large areas of water as the creeks cannot contain the flow.

The main course of the Warburton has many small erosion lines draining adjacent country and forming an organic growth like pattern which is only apparent from the air.

Parallel sand dunes extend like fingers towards Warburton Creek.

In an endless combination of water and wind shaping the landscape, the fingers of sand dunes encroaching on Warburton Creek from the South will be swept away and returned to Lake Eyre where the sand will again be blown out during the next big dry.

Droughts, floods and wind are major forces shaping the Tirari and other Lakes Eyre Basin deserts. Fortunately the area had received well above average rains before we arrived and the desert was blooming.

From Cowarie Station we headed to Kalamurina Sanctuary where, by prior arrangement with the Managers, we camped for a couple of days on Warburton Creek. For more information on Kalamurina see the Australian Wildlife Conservancy web site here:

Entry gate to Kalamurina Sanctuary located on the Eastern boundary in a swale just short of one of thousands of sand dunes.

Wildflowers blooming in the sand country adjacent to Warburton Creek, Kalamurina, Tirari Desert.

The Sandhill Canegrass (Zygochloa paradoxa) was also flourishing in the wet conditions. The grass is important Eyrean Grasswren habitat.
 
We were fortunate to visit this area during a boom time. During prolonged droughts, which are frequent here (30-40% of the time), the Warburton would have been dry and the surrounding country would have been less attractive with a meagre bird species presence. Huge dust storms when the winds get up are a real possibility and another reason not to visit during droughts.

The next post Tirari Desert - Part 2 will include some photos of birds captured along Warburton Creek.