Saturday 27 December 2014

Staying Put


Home is where the eagle stays! Today marks the 560th consecutive day that our wonderful Wallu has spent in a fixed home range at Lorna Glen in central Western Australia. Except for a few days where he was recorded about 60 km east of his territory for part of the afternoon, Wallu hasn't left home, roosting here every night for the past 18 months. This is a relatively small area for a large eagle, especially in such an arid environment, a sign that food supply in this habitat is ample. At the beginning of this study I expected the home range to be at least 100 km2, but Wallu occupies an area less than half this size. In the future tracking more adult eagles will give us a better idea of the average home range in this landscape.

Saturday 20 December 2014

To the Water's Edge


The last time we checked in with Jarrkanpa, he had only just fledged, making his first flight at the age of nearly 3 months. The map above shows his very limited movement from the nest, which is situated just behind a line of dense Melaleauca shrubs that border the edge of a seasonal lake.

Eleven days after his first flight, Jarrkanpa had moved to a new perch and over to the water's edge:


And by yesterday, just over 3 weeks after fledging, he had learned to move along the whole edge of the wetland, flying to roost in a patch of tall gum trees about 700m east of his nest (as shown on the far right of this below map):


You're probably wondering why I'm saying 'wetland' when these maps clearly show a white claypan which doesn't look very wet! But if you cast your mind back to the updates from earlier this year, you might remember this post from March which showed the amazing flood waters that soaked the landscape. Although not shown in these maps, the wetland has remained remarkably full for most of the year, attracting large numbers of breeding waterbirds including swans, ducks, stilts and terns. This abundance of birdlife, together with the flourishing mammals attracted to the water and surrounding green pasture, will have produced some great food for eagles, a key reason for the breeding success of nearby eagle pairs. 

Here's a picture taken just after sunset on a late October evening, showing a foreground of samphire still inundated with rare outback surface water. Although it is now dwindling as daily temperatures rise, this water is still present today, and it will no doubt be very helpful at keeping local wildlife (i.e. eagle food) alive, and building Jarrkanpa into a strong young wedge-tail well equipped for his life ahead.


In the last post I also uploaded a map predicting the size of Jarrkanpa's parents' home range. We can now look at the past 3 weeks tracking data and see how he has started to fill out my predicted home range quite nicely:


My predicted home range for Jarrkanpa prior to him fledging.

Jarrkanpa's home range 3.5 weeks after fledging. Wallu's territory is shown in the background.

You can see from this early tracking information that, as Kuyurnpa did last year, our little boy is now starting to expand his flight area to fill out what is probably his parents' home range. How far will he have moved when we next check in?

Saturday 13 December 2014

The World Premiere!


As people piled in to the Haydn William's lecture theatre on Tuesday night, gradually changing the unform grey of the seats into a sea of colour, my nerves raced! The night had finally arrived. It was time to reveal for the first time the film I'd been working on for the past 3 years.

The world premiere of 'Where Do Eagles Dare?', the film which follows my journey to satellite track adult Wedge-tailed Eagles in Australia for the first time (i.e. the first part of the project documented on this website), saw nearly 500 people attend one of two screenings at Curtin University's Haydn Williams Lecture theatre earlier this week. Both evenings began with a fabulous Welcome to Country performed by Nyoongar elders Marie Taylor and Robyn Collard from the South West Aboriginal Land and Sea Council. These welcomes included a fantastic Dreamtime video which you can see on their website here. I then screened a short film about the successful use of a nesting box by Carnaby's Cockatoos, before I presented special gifts to all the people who I've had the fantastic assistance of in making the film. They included my partner Gill, my good friend Judy, field assistants Mick, Jeff and Mike, my bird banding supervisor Neil Hamilton, and especially the girl behind all the film's music, Storme, a singer-songwriter from the Perth hills.
 

Then it was time to show the film, which runs for 1 hour and 15 minutes. It was certainly a great thrill to sit back and watch the reactions of the audience to all the sequences I'd spent the past 6 months building in the edit suite. One of the highlights was having 2014 West Australian of the Year and former Chief Scientist Professor Lyn Beazley attend, who I had the pleasure of giving a guest seat.

Thanks to all the wonderful people who supported this event by attending one of the screenings, and to the people who couldn't make it but who kindly sent their words of encouragement. Keep your eyes out for the DVD, which will be available very soon in the New Year!


Professor Lyn Beazley and her husband Richard were special guests to the Friday screening.

Tuesday 25 November 2014

On the Wing



Jarrkanpa has now learned to fly - but only just! Today is the first day we have recorded satellite fixes away from his nest, indicating his first (albeit very small) movements. It is now one week since we satellite-tagged him, and based on an age estimate calculated when he was banded, Jarrkanpa has flown the nest at the age of approximately 90 days.

Can you imagine the feeling of making your first flight, lifting up above the tree-tops, floating on the wind, and getting an even greater perspective on the wetland at the doorstep of your nest? It must be pretty amazing!

We know juvenile eagles' first movements tend to mirror those of their parents very closely, based on field studies of wedge-tails, and from Kuyurnpa's post-fledging movements last year as tracked by satellite (although for this study we only have a sample size of n=1!).  So based on this, I expect that tracking Jarrkanpa's progress should reveal approximately where his parents' home range extends to. As today is the 'official' fledging date, I've decided to make a prediction of the size of this range, using the simple map below (click to enlarge). This is based on the proximity of neighbouring nests which I know have been active in 2014.



You might recognise the wetland shown in this map - it is the same one covered by much of Wallu and Wurru's home range. The nests of their two 'southern neighbours' are shown at the bottom left of the map - N62 and N72. Jarrkanpa's parents' neighbours' most recently active nest is N44, to the east. We'll see over the next few weeks how accurate this prediction is. Watch this space!

Tuesday 18 November 2014

Jarrkanpa


Meet the newest member of our satellite-tracked eagle family, a beautiful juvenile Wedge-tailed Eagle called 'Jarrkanpa'. This word comes from the Martu language and means 'young boy', and I decided it would be a fitting name for a ~10 week old male eagle.

Today Jarrkanpa was removed from his nest and fitted with a solar PTT, making him the fourth Lorna Glen eagle to be tracked with satellite technology. But it wasn't the first time I'd handled him. Just over a month earlier, I was nest-searching the edge of Lindsay Gordon Lagoon with my Mum in tow as a volunteer, when I stumbled upon a brand new eagle nest in a previously unrecorded territory. This nest housed one chick, which, when I scaled to the top of its nest tree, greeted me with open wings! (Not in the welcoming way that this saying normally implies though - opening wings and a gaping mouth are signs of a threat display that many nestling raptors exhibit, making themselves appear larger and more threatening, useful for warding off would-be predators).


This photo shows Jarrkanpa at about 5 weeks of age on the day of discovery. You can also see the range of prey animals, including a Dinner Plate Turtle (Chelodina steindachneri), that share the nest cavity with him. A couple of weeks later I climbed this nest again and removed the chick, which was fitted with metal leg bands - this is part of our research to gather further information on the dispersal and survival of juveniles. A photo of him having the bands fitted is shown in the fifth photo down of the 'Cute Chicks' blog post, which also shows a picture of me at the nest (second photo down).

Today, as Neil and I approached the nest, this is what Jarrkanpa looked like:


As these pictures show, the growth rate of young eagles is incredibly swift; this is something that has never ceased to amaze me. Once safely removed from his nest, Jarrkanpa was placed on a soft sheet on the ground and blinded with a falconry hood. Neil held the bird in position as I fitted the transmitter, which went on very smoothly as the harness had been pre-made.

A solar PTT being fitted to Jarrkanpa's back with a specially designed Teflon harness.

After a couple of quick photographs I returned him to his nest. The young eagle instantly assumed a threat display, standing boldly on his now powerful feet and spreading his nearly-complete wingspan. I wondered how long it would be before he would make his first flight. Satellite tracking would soon tell me!




Monday 27 October 2014

Hanging near Home


The last time we heard about Kuyurnpa, she had just completed a giant journey from the Pilbara region of WA, into South Australia, then back to the centre of WA again. Her life since then has continued to be filled with high adventure! After crossing the Great Victoria Desert for the second time, Kuyu headed north again, and settled down on Roy Hill station in the Pilbara. We don't know if she 'met someone' or just stayed in an area of good food supply (perhaps with other young eagles of similar age), but the Roy Hill area and surrounds became her home for the next 10 weeks. Her tracking data showed a concentration of points with a total area of just over 10 000km2 (about 2.5 million acres). Here's a map (click to enlarge):


As if it was in her diary to be 'gone by the end of the month', Kuyu left Roy Hill on 1st October, and once again headed homeward, roosting just 10km south of the south-eastern Matuwa boundary, 40km from her natal nest. She didn't stop there though, and continued eastwards as far as Lake Carnegie, where she has mostly remained for the past 3 weeks. However, it looks as though Kuyurnpa has made a couple of 'attempts' to get closer to home, with two roost sites being just 10km east of Matuwa's eastern boundary, and a few day fixes have shown her soaring over Matuwa itself. Below you can see the most up-to-date map of this amazing young eagle's movements.

Kuyurnpa's latest GPS fix is the point near the north-western extremity of Lake Wells.

In a few days it will be a year ago that Kuyurnpa left her nest for the first time, and 7 months ago that she left her parents' home range. Since fledging she has now travelled 14 800km around 2 states of Australia! It has been an incredible journey, both for the eagle herself, and for us as we've eagerly tagged along for the ride! I hope you've enjoyed follow her as much as I have. Where will she fly to next?

Friday 17 October 2014

Cute Chicks


Wedge-tailed Eagles are now well into their breeding season at Lorna Glen, and over the last few days we have been checking nests for breeding success. So far five nests have had large chicks! The one pictured above is the same chick shown at the start of the previous blog post, just 6 weeks later - isn't the change incredible!? To gather data on their dispersal I am ringing/banding the eaglets with coloured and numbered leg rings. This will hopefully make them recognisable in the field when the eaglets fledge and leave their natal territory, and give us information on where these young birds disperse. 

Kuyurnpa is an eagle chick that was fitted with a satellite tracker in 2013, and while ringing cannot provide as much detail as satellite tracking, it does at least create an opportunity for a re-sighting at some stage in the future.

Lowering down an eaglet from a particularly small Wedge-tailed Eagle nest. Don't worry - I'm harnessed in!

To fit the rings, eagle chicks are removed from their nests and lowered to the ground in a closed bag. They are then placed gently on a folded sheet where they sit quite happily as they are processed. I followed the same methods used by Golden Eagle researchers Ewan Weston, Rab Rae and Stuart Rae in Scotland, whom I accompanied on several ringing forays in the highlands earlier this year. This method allow for efficient processing and minimal impact to the birds.

Neil Hamilton holds an eagle chick as I attach the leg rings.

Once on the ground, the first step is to fit the rings to the eaglets' legs. An Australian Bird and Bat Banding Scheme (ABBBS) band is fitted to the right leg, then a unique colour band (right) is placed on the left leg. Bands do not harm the bird in any way - they have been designed to fit the leg comfortably: loose enough so they don't cause damage, but tight enough so they don't come off or get caught on vegetation. Furthermore, all banding conducted at Lorna Glen is licensed under the West Australian Wildlife Conservation Act and has been approved by an Animal Ethics Committee. The colour bands I am using are also the same design as those being used by my friends in Scotland. I am hoping they will be visible enough to be seen by any keen bird-watchers or photographers who can report sightings to me once these eaglets take to the air and leave home!

After the ringing is done, several measurements are taken from the bird, including weight, head length, wing, leg and talon length - these can be used to age and sex the eagle at a later date.

An eaglet aged ~7 weeks sits calmly as it is fitted with an ABBBS band.

The head-bill measurement is taken after fitting both leg bands (you can see the blue colour band on the eaglet's left leg.

When the banding and measuring are complete (the whole process takes about half an hour), the eaglet is placed back in the handling bag and hoisted back up to its eyrie. Here it sits and waits for its parents to return to the nest, hopefully with food. The adults have more than likely been watching the whole process from somewhere up high, but our presence at the nest does not significantly alter their behaviour. At this stage of the nesting period it is common for the parents to spend most of the day off the nest and away hunting. Their chick sits on the nest, keeping to the shade when it can, and watches over the surrounding Mulga shrubland, honing its skills at spying moving objects, and occasionally standing for a practice at wing-flapping.

Removing an eaglet from the handling bag to return it to its nest.

Several days after ringing each wedge-tail chick, I returned to check up on their progress, to ensure their parents had returned with food since the disturbance, and to check the rings were still in the right place. All were doing well. This one, the smallest (probably male) eaglet, was sitting up waiting to greet me as I poked my head over the edge of his eyrie.



Below you can see an ~8-week old eaglet with its new rings. This was the oldest chick we banded and it had quite large wings and very well-developed body feathers compared to the others. It should be easily recognisable with the blue colour band '005'. Where in WA will this young wedge-tail turn up next?


Thanks to Neil Hamilton, my 'eagle handling mentor', for overseeing the process of eaglet ringing. I would also like to thank John Angus, Pam Cherriman, Gill Basnett, Mark Jeans, Ayla Wilson, Bruce and Kaye Withnell and Tammy Elliott and her family for their assistance during the past few weeks.

Friday 10 October 2014

Nest Failures


Smashed eggs! Never a nice thing to find on any bird's nest that you have been monitoring with the hope it will soon house an eagle chick. However, such findings are to be expected and teach us a great deal about the both the bird and its environment.

This photo was taken on Wedge-tailed Eagle Nest 2 at Matuwa (Lorna Glen). You can read more about the discovery and its implications on my personal News blog here.

Monday 6 October 2014

Wallu After 16 Months


As the sun began its decent late this afternoon, I drove along the edge of a dry salt lake past 'Rabbit Ridge', and was extremely excited to see Wallu and Wurru launch from among the samphire! The pair had been on the ground only 50 m from the road and caught me completely by surprise. I suspected they'd been hunting rabbits from within the dense cover at ground level. Although unusual, I've seen this behaviour a couple of times before. Eagles are quite capable of running along the ground to catch prey if they manage to surprise it, and what better way to get a rabbit than meet it face to face?

It was brilliant to see Wallu in good health and capture a fleeting shot of him bearing his PTT, which can be seen the above photograph. Wallu only flew a hundred metres before alighting on the ground once again. Was he determined to get a rabbit?

Wallu alights in the samphire about 100m from where we flushed him.

He might've been hungry for himself, but we know he wasn't after prey to feed a chick. Unfortunately we discovered last week that Wallu and Wurru had another unsuccessful breeding season this year. When looking at the tracking data in June and July (nesting season), I started noticing a pattern in Wallu's daily movements. He would often be at Rabbit Ridge at dawn, then at mid morning we would see one or two fixes at his nest site.

Here are some maps (click to enlarge):

A day in the life - Wallu has travelled just over 25 km and roosted at two favoured hunting sites.

This map shows Wallu beginning his day at the eastern edge of a salt lake ('Rabbit Ridge' - cluster of red dots, centre right), and flying to his nest at 11am. He then soars to about 1000m above sea level and remains at this altitude for the middle of the day, drifting from the far western end of his territory (green circle) to the far east (yellow circle), and back to the middle. By sunset he has gone to roost at another favoured hunting spot, near an old farm well just north-east of Rabbit Ridge. The total distance covered was about 25km - not a bad day's work!

Another day, Wallu roosted much closer to 'home' on two consecutive nights - the green circle around the red dots reveals the spot, just 1.3km from his nest (see map below). At 6am he was at roost, but by 7am he was on the nest, at 8am he sat in a tree high on the ridge 800m to the north. At 9 and 10am Wallu was back on the nest, then as the clock struck 11am, he was airborne, cruising at 30km/h above Rabbit Ridge (as shown by the blue arrow). He spent from noon until 2pm sitting in his perch tree only 50m from the nest, headed off 'rabbiting' again from 3-5pm, and by 6pm, Wallu roosted back at the same spot again (green circle).




This data is consistent with Wallu delivering prey to his incubating female, 'guarding' her from a nearby perch, and, on occasions where he spent more time at the nest, taking on an incubation shift while Wurru has a break, perhaps to feed or stretch her wings.

In August I was thrilled to visit their nest (Nest 57) with Neil Hamilton and make an exciting discovery, confirming that Wurru had laid eggs. As we neared the nest tree  we crept through the bush, making every effort to keep a dense thicket of mulga trees between us and the nest. A stiff breeze ruffled the foliage, and through a few fine gaps I could make out the shape of Wurru sitting on her nest. She was incubating!! We retreated quickly as to not disturb her, our movements being concealed by the quivers of surrounding vegetation constantly in motion from the wind. Such conditions are good for remaining 'camouflaged' to an eagle's eye, which on a still day detects even the slightest movement from a long distance.


I arrived back at Lorna Glen last week (late September), excited to return with the strong hope that our inaugural satellite-tagged eagle would become a father for the first time. My Mum was accompanying me as a volunteer to help with my fieldwork. However, we were both disappointed to find Nest 57 empty (right). It contained fresh Eucalypt leaves and a slightly flattened nest cavity, but no eggshell, which almost certainly means the eggs had hatched but the chicks had not survived past their first week or so. Why?

Food is the ongoing factor which influences raptor breeding success, and although Wallu hunts regularly at several active rabbit warrens, and has access to other prey (kangaroos, monitor lizards) in his home range, he still has to supply plenty to a growing family, and this isn't easy in the arid zone. There are several other factors which also influence breeding success, and you can read about these here.

October now marks the 16th month we have been tracking Wallu by satellite, and even after this time we are still learning new things. It is only through satellite tracking that we are able to have such detailed insights into the lives of these magnificent eagles.

Tuesday 16 September 2014

RIP Gidjee


Today we received the confirmation that our beautiful girl Gidjee is dead. Her body was recovered at the last known location where her PTT stopped transmitting back in May. This is very sad news but it is to be expected that when studying wild animals, they often don't survive. We don't know how Gidjee died and as the location where she 'went down' was so remote, we weren't able to recover her body in time to perform an autopsy. However, we do know that that this adult wedge-tail survived with her PTT for 10 months, reproduced successfully (which requires peak physical condition) and managed to see her chick through to fledging and dispersal. All sightings of Gidjee, including the last time she was seen alive in April, showed her to be perfectly healthy.

It seems highly coincidental that Gidjee had survived well in a fixed home range with ample resources and no competition from other eagles for nearly a year, but after a sudden unexpected departure from 'home', she only lasted 4 days. Was she driven away by a rival adult at the onset of the 2014 breeding season? This seems likely, given that only a week after her leaving, her male was seen paired up with a different female (at least we think this - or it may have been a different pair entirely who 'took over'). Wedge-tailed Eagles are said to be 'monogamous' but such loyalty can only be proven when individuals are marked and studied closely. The reality is that few such studies exist, and the monogamy we talk about may just be a convenient (and somewhat romantic) way to think of our largest eagle. Our satellite tracking study has now detected an adult female leaving her home range, and the location of her fate, something which would normally go unnoticed. This finding is extremely interesting and very exciting - it is just the sort of thing we conduct research for.

Of course their are other possible explanations for Gidjee's death: she may have been shot, poisoned (dog/dingo baits containing Strychnine are still regularly used throughout this region), and even died of old age (we don't know how old she was at her time of capture last year). Ultimately we can only speculate and will really never know what really killed her.

The good news is that Gidjee will live on in her daughter Kuyurnpa, who is still going strong and continuing her travels around the outback of WA. And it's great to know that these incredible GPS trackers are serving their purpose by helping unlock the secrets of these majestic birds of prey.

Saturday 6 September 2014

Film Premiere


Today I'm pleased to announce that a date has been set for the documentary film about this tracking project, called 'Where Do Eagles Dare?', to premiere in Perth. You can watch the trailer for the film by clicking the 'Documentary' tab above. The above flyer contains the info you need to attend the two screenings. You can also visit this link to find out more and see a direct link to the ticketing page. I hope to see you in December!

Thursday 14 August 2014

Breeding Time



I'm currently back at Lorna Glen and it's the time of year to check eagle nests for breeding activity. So far our fieldwork has started well with many nests containing eggs. One early-nesting pair of wedge-tails already has a chick, which I photographed today at close quarters - yes, it is the very cute eaglet shown above!

A typical clutch of two eggs on an active Wedge-tailed Eagle nest at Lorna Glen.

Good rains in February and March this year transformed the desert country into a flourishing landscape - wildflowers bloomed and waterbirds moved in to breed on the salt lakes. Although the water is rapidly disappearing, some very pretty blossoms remain and we have been amazed by a particular white flower that appears like snow among the red dirt and spinifex.


I am hoping it will mean a good year for the eagles too but time will tell if the pairs that have laid can find enough food for the next 3 months to keep their hungry eaglets alive and well until fledging.

And to finish with - on the first day of nest checking, I was extremely excited to see Wallu at his regular rabbit warren feeding site. He took to the air quickly... my camera's memory card showed 'full' as I frantically tried to take some photos... but I did manage to snap one picture which clearly shows his PTT aerial. Will him and Wurru produce a chick this year? More updates from the desert coming soon.



Wednesday 16 July 2014

In the News

The Wedge-tailed Eagle Tracking project has been in the news this week after I was asked to be interview on ABC Radio in Western Australia. Below are a few links where you can read more.

ABC News Story:
http://www.abc.net.au/news/2014-07-11/biologist-discovers-wedge-tailed-eagles-fly-much-higher-than-th/5590964

Interview with Arthur Muhl, ABC Midwest and Wheatbelt:
https://soundcloud.com/abcwa/t-tracking-wedge-tailed-eagles-in-the-wa-outback

Monday 14 July 2014

A Quick Change of State


Kuyurnpa heads to South Australia! This is what the last 10 days of tracking data showed today - another huge flight of over 1500 km from the area between Lorna Glen and Kalgoorlie right down towards the Nullarbor Plain. Kuyurnpa left WA for a short time, roosting on the night of 10th July just 50 km inside the SA border. She then headed back into WA, travelling north-west to the middle of the Gibson Desert. This data paints an amazing picture of an eagle at its most vulnerable stage of life, its first year, crossing two of the most inhospitable deserts in Australia. Where to next!?

Friday 27 June 2014

Heading Home and Beyond


Check out this amazing journey! Kuyurnpa never ceases to give me a surprise when I excitedly log on to download her latest satellite tracking data. This evening's map shows that in 10 days she has flown over 1000 km, heading directly south from the De Grey River area, her favoured spot of the last month, and returning all the way back HOME to Lorna Glen! Kuyurnpa spent 21st and 22nd June on the property, and on 23rd June passed less than 20 km to the north of the fenced enclosure, continuing west to roost on the neighbouring station that evening. This is the first time she has flown near her natal territory since beginning dispersal at the end of March.

Continuing to create new findings for us, she carried on south-west, roosting on Lake Way near Wiluna for the next couple of days. The last GPS fix on Kuyu shows her roosting at Lake Maitland, about 100 km north-east of Leinster, the southern-most location yet visited by our adventurous little girl!

If you live or happen to be travelling in this area over the next few weeks, please keep you eyes peeled for Kuyurnpa. She can easily be identified by the 20 cm antenna protruding from her back! If you think you've seen her or have a photo, please email me.

Monday 16 June 2014

Lining Time


It's nest lining time at Lorna Glen!

Wedge-tailed Eagles begin their breeding cycle early in the year, timing events perfectly so the chicks hatch at a time when the surrounding ecosystem is rich with prey, maximising their chance of survival. Often this prey comes in the form of young mammals that are 'bite size' and naive enough to catch easily - especially young macropods (kangaroo family) and rabbits, which are the preferred prey items across Australia. The first stage of nesting is preparing the chosen nest, which normally begins in May and June. Eagles spend quite a few weeks lining their nest with sprays of fresh green leaves, most often using Eucalyptus, but where this species is not available, Acacia is a commonly used alternative. In the lead up to laying, the lining probably helps advertise that the nest and surrounding territory are occupied. More importantly it creates a soft bed on which the female can sit on and depress into a small cup to cradle her eggs, when eventually she is ready to lay.

The above photo shows an eagle nest that was freshly lined with Mulga (Acacia aneura) sprigs in June 2013. Here the same nest photographed at the end of the breeding, that shows the faded lining and a slight cup:


 There was no evidence of eggshell in the nest which would be expected if eggs were laid. The owners were a young, inexperienced eagle pair that didn't end up laying eggs. While we often think all birds should nest every year, it is normal for some not to, and for others to attempt but fail. Such is life in the arid outback!

Sunday 1 June 2014

Completing the Loop


Back north! Kuyurnpa completed her 10-day desert trip today after continuing north from her last position, and returning to... guess where? That favourite spot at the mouth of the De Grey River. The journey is shown in the above map - click to enlarge. It would be great to get inside her head and know what caused her to 'wander off' on a 930 km trip - searching for a mate? I think it is too early for this given she is still in her first year. And perhaps she just loves flying? I know I would.

It is more likely that Kuyu is wandering to become familiar with her surroundings, and is travelling to wherever there is food. Young eagles especially like to take advantage of carrion along roadsides, and this food source probably helps many through dry times. Although many eagles get killed while feeding on kangaroo carcasses, this cause of death has probably become a substitute for natural death caused by drought, and I suspect it has little impact to the population.

This recent trek takes Kuyu's total distance travelled since beginning dispersal to a whopping 6 800 kilometres!!! That's about 1.5 times the width of Australia. Not a bad effort for a journey that has only lasted just over 2 months.



A sub-adult female wedge-tailed eagle prepares to kick the crows off and take her share of this road-killed red kangaroo. Her bulging crop tells us she has already recently fed elsewhere.

Tuesday 27 May 2014

Desert Wanderer


Kuyurnpa is becoming a real wanderer! Today's tracking data showed that she has once again ventured inland, moving another 420 km south-east of her latest Pilbara Coast hangout. She left the mouth of the De Grey River and followed this waterway upstream, roosting for the night just east of Marble Bar, before travelling a whopping 292 km the next day to spend the night at the edge of the Little Sandy Desert, just east of Newman! This seems amazing, but when you are an eagle that can cruise at 1600m above sea level doing 85 km per hour (as Kuyurnpa did that day), literally riding the wind, it's easy to put those miles behind you! Another 140 km journey northwards had Kuyu roosting between Rudall River National Park and the Newman-Marble Bar Road. Where to next?

Tuesday 20 May 2014

The Pilbara Coast

Imagine being born in the middle of the desert but knowing one day you would fly so far that you would be able to reach the ocean! Kuyurnpa's lengthy day-trips during her dispersal from 'home' for a month have become shorter now as she explores the coastline between the De Grey River (east of Port Hedland) and Karratha. Here are 2 images which show her exploration of a 160 km stretch of the Pilbara coastline.

The first shows Kuyu's movements from 29th April, when she reached the coast after a 4000 km+ flight that took her (as the crow flies) 700km from Lorna Glen, until 6th May, when she had begun to follow the coast west past Port Hedland. The second map shows how, after tracking the Turner River southwards for a short distance before continuing slightly further west, she about-turned and moved back in an easterly direction, revisiting the area between the De Grey River and the Port Headland salt farm that gave her her first ever glimpses of the ocean. Her current position is about 670 km from her natal nest at Lorna Glen.

Click on the first map to view it in more detail, then hit the right arrow key to 'add' Kuyurnpa's extra journey. Where will she head to next?