Welcome to the News section of the iNSiGHT Ornithology website (
www.simoncherriman.com). This blog contains updates about various things I've been up to, interesting environmental issues and observations I make regularly while going about my day. It is designed to be fun AND educational, and inspire you about our wonderful natural world. Happy reading!

Tuesday, 1 November 2011

Raptors Out Back

And so on the first day of the new month I return to Perth after an amazing adventure into Australia’s interior. It lasted only three days but felt like we were out bush for weeks. Here’s how the story began...

Gill and I left Perth early in our car packed to the brim with camping, climbing and photographic equipment. Oh, and a bit of food. There was just enough room for us! It was still quiet as we turned onto Great Northern Highway and began the journey north, bound for Lorna Glen Conservation Reserve on the edge of the Gibson Desert. Our goal was raptor related: to begin a study of Wedge-tailed Eagles at Lorna Glen, and in particular find out if they were eating reintroduced mammals.

The Department of Environment and Conservation acquired Lorna Glen in 2000 and has been releasing endangered mammals  from Barrow Island in an effort to reestablish them in a landscape managed for conservation. Some species like Brushtail Possums (Trichosurus vulpecula), Golden Bandicoots (Isoodon obesulus) and Bilbies (Macrotis lagotis) have fared well in their new home, but others have had problems surviving. One possible reason for this is predation by raptors, especially wedgies, so that’s what we were going to investigate: what is the status of eagles at Lorna Glen, and to what extent might they eat our furry friends?

After the long drive of about 1200 km we arrived at the Lorna Glen homestead in the dark. It was exciting to drive down the entrance road knowing there was the possibility of seeing a Bilby cross the road in front of us! Galahs squawked outside in nearby River Redgums as they settled down for the night, and we settled into our bunks for a well-earned sleep.

We spent the follow three days exploring the amazing Mulga plains in search of Wedge-tailed Eagles nests, managing to find three in total. One of these was old and inactive, and one had been lined with leaves sometime in the last few months but was also inactive. While looking for any bones below this nest (left), Gill's keen eyes spotted a small pile of scats, which she knew belonged to a reptile. This led her to make a closer inspection of the large cracks in the nest tree (which you can see in the below photo), and our faces lit up when she spotted lizard hiding inside!

This gorgeous little reptile is known as Pygmy Spiney-tailed Skink (Egernia depressa). The species lives in arid regions of Australia and lives almost exclusively inside the cracks in trees, very often Acacias, staying hidden inside from predators. The spines on their tail are an adaptation which enable the animal to lodge inside a narrow cavity, preventing them from being removed by predators. Pygmy Skinks leave the protection of their hiding spots during the day to bask, and defecate in the same location, leaving a small pile of pooh (known as a 'latrine'). This was a great find, and we learned that the tall Gidgee trees which eagles build nests in are home to more than just wedgies!

On the third day we spotted a third eagle nest and hurried to check it out. As we approached the nest I could hear a loud yelping from nearby and we were excited to see a newly fledged juvenile eagle perched in a dead tree. He soon took off and began circling low overhead, and shortly afterwards was joined by his large, dark parents. We knew THIS nest had been active and were rewarded with a large quantity of prey remains below it which I later analysed to determine these eagles had fed upon a few Endangered mammals, including Mala and Golden Bandicoots. The next thing to determine whether the eagles killed enough of these species to harm their numbers.

The final day began exploring an area of tall Eucalypt trees in the hope we would locate another nest. We did - but this one belonged to Whistling Kites, not wedgies. Although it was not our specific target it still warranted a closer look, so I climbed the tree to find 2 small kite chicks and a freshly killed Galah on the nest. One of the kite chicks responded instantly to my movement and poked his head up to pose for this photo! (You can also see the freshly plucked Galah carcass in the background).

This find had us filled with enthusiasm to find more nests, but we had some disturbing news on the radio which caused an end to our trip. There was a storm coming... a big one... and we had to make the spare-of-the-moment decision to either leave ASAP, or be stuck out here for 2-3 weeks. In the arid region of Western Australia, a dumping of 20 mm of rain makes the ground turn to slush and brings a halt to anyone wishing to drive vehicles around. It then takes quite a few weeks of fine weather to dry the ground out enough to drive on again.

Seeing as Gill and I both had commitments back in Perth within the next week, we had no choice but to pack up and leave. After a hurried session of cramming all our gear into the car, we joined 2 other teams of scientists and headed for Wiluna, hoping to beat the rains. We didn't hold much hope though after seeing the sky ahead of us becoming blacker by the minute...

The rain began about 80 km to Wiluna where we hoped to reach the safety of a bitumenised road. Puddles in the road gutters turned to large pools and eventually fast-flowing rivers and the rain increased and lightning lashed the sky overhead. I felt a slight hint of reassurance knowing that we were in a convoy with other cars who had towing equipment, but I was still slightly nervous at the thought of the rising water. Then, 30 km from Wiluna the road turned into one, GIANT puddle! Here's my point of view looking out the window:

This sight was initially very daunting but after a few metres we realised that although waterlogged, the substrate was still quite firm and my car motored along through the 'river road' easily. I felt like I was driving a dingy up some isolated river in the Kimberley! This stretch lasted for several hundred metres, then there were some 'dry' patches, more water, lots of mud, and finally we reached the bitumen.

It was an amazing way to travel out from the 'desert', proving that our ever-changing environment is unpredictable and can turn roads into rivers in the blink of an eye. The eagle research may have been cut short, but I plan to return next year to carry out more nest searches and increase the understanding of my totem animal, the Wedge-tailed Eagle, in this outback wonderland.

To check out pictures of more wildlife and landscapes at Lorna Glen, check this album in my Photo Gallery.

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