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!

Thursday, 1 December 2016

Kala


The rapid growth of Wailitj / Wedge-tailed Eagle nestlings never ceases to amaze me. The above photo was taken in mid-September, when one of the Perth Hills nest sites I regularly monitor celebrated the arrival of a new nestling. This discovery was particularly exciting as the eaglet's mother, a 'new' immature female, was first recorded on this territory in 2015 and this was her first ever breeding event! In this photo the eaglet is only 2 days old, and has hardly a hint of predatory bird about it.

One day short of being a fortnight old, this eaglet had more than doubled in size, but still maintained its white, fluffy appearance:


Nine weeks later, however, the same bird had made a rapid transformation, and at 65 days old, possesses the powerful wings and piercing stare of a formidable hunter.


This photo was taken early last week when I visited the eyrie to check the bird was fit, healthy and suitable for satellite-tagging. Two days later I was extremely excited to return with my PhD supervisors Trish Fleming and Jill Shepherd, members of Murdoch University's Animal Ethics Committee Moira Desport and Margot Seneque, who have been wonderfully helpful in assisting me obtain the appropriate approvals for my research, and Parks and Wildlife ecologist Geoff Barrett, to fit a satellite transmitter. It was a thrill to be out bush on a fine, sunny Kambarang (spring) afternoon with an enthusiastic bunch of fellow conservation-minded scientists, and share the sights and sounds of an eagle site that I have visited annually since first discovering it 12 years ago. After a short hike through some beautiful open Jarrah forest, we began the scramble down slope into the rugged Helena Valley, wading through shin-scratching patches of granite heathland and peering past the canopies of wonderful Wandoo trees. Soon we were looking onto the eyrie, where a beautiful juvenile Wedge-tail, three days shy of turning 10 weeks old, sat sunning itself.


It wasn't long before I was scaling the nest tree and lowering the juvenile male eagle down in a handling bag to Jill, who held him while I took measurements, applied leg-bands and fitted the Platform Terminal Transmitter (PTT). To continue the theme of using Noongar names for all satellite-tagged Perth region Wedge-tails, and to use a name relevant to the area in which this eagle hatched (Kalamunda, which is also the Shire in which I hatched 32 years ago!), I decided to name him 'Kala', which in Noongar translates to 'fireplace' or 'home/hearth'.

Moira inspects Kala's beautiful new primary feathers, which are close to lifting him skyward.


When the transmitter attachment was complete I re-climbed the nest and hauled the handling bag aloft, taking care to ensure its precious contents remained unharmed. Placing Kala back on his nest allowed me a quick glimpse of a recently delivered prey item, a large Karda / Gould's Sand Goanna (Varanus gouldii), whose leathery skin had been partially torn open and some of the head and torso consumed. It was great to know the eagle would have ample food until the next morning, when his father would likely be delivering another vertebrate from the surrounding ecosystem as breakfast. As deep shadows gradually engulfed the valley, we hiked back up the slope and across a large slab of granite, marvelling at the sight of Kala's parents who hung overhead, riding the gentle westerly wind with ease. They had no doubt been watching our every move from the heavens, and I felt excited to know we would soon be able to satellite-track their son when he first soared up to join them.

Reptiles like monitor lizards can be favoured prey for Wedge-tailed Eagles, especially in arid ecosystems where they are relatively abundant and conspicuous from the air.

Today, 77 days after he entered this beautiful world, I returned to Kala's eyrie to see how he was getting on. Looking level with the nest from a steep slope behind it gave me a good view of the eagle's back, and I was able to see straight away how he had now preened the harness into his body feathers, which made the PTT sit comfortably between the shoulders, partly shielded by scapular feathers and almost invisible. Photos of newly attached PTTs can create a skewed perception of how seemingly large and heavy these devices are (they are actually relatively small and only weigh 70g), so it was great to be able to capture a few images of a 'settled in' transmitter, which accurately reflects how it looks on the eagle after it is released.

The PTT aerial casts a thin shadow across Kala's left scapular feathers.

As I walked down towards the base of the nest tree, Kala hopped over to the edge of his eyrie, glancing back at me, forward across the valley, then back at me again. I decided to sit and watch, fully aware that my presence had prompted this evasive behaviour, but eager to observe him for a few moments and see if I could guage how close he may be to that first big moment. I was transfixed at the scene in front of me. Kala continued to head-bob, looking across the valley, and shuffling as gentle gusts of wind attempted to unbalance him. Suddenly he leaned forward and launched onto a large limb, then clambered up and away from the eyrie, continuing to survey the valley scene before him. My anticipation grew. The nest-tree glowed in magic light from the season of Birak's first setting sun.


Another gust of wind, slightly stronger this time, prompted Kala to partly open his wings, still shuffling on his legs, but gripping firmly with his mighty talons. More head-bobbing. Then another leap forward, this time onto an even thinner branch that probed out into the valley, placing him further away from the eyrie. I could feel the eagle's keenness to fly. I knew if I turned around to walk away, I would miss something special. More peering across the valley, like a nervous human waiting to take the plunge on their first ever bungee-jump. Then suddenly, with one last glance back at me, he stared forward at an unknown point on the hill opposite his eyrie, leaned forward, squirted a jet of white back at the nest tree, then spread a mighty wingspan against the open air and threw himself at it. A faint sound of several powerful wingbeats reached my eardrum, and Kala sailed downwards and outwards, disappearing behind some foliage. This was it. Kala was airborne!

Kala is the third juvenile Wedge-tailed Eagle to be satellite-tagged in the Perth Hills this year. More information about the others, and their progress, will be uploaded as it comes to light.

Wednesday, 23 November 2016

Yirrabiddi


I'm SOARING!! Today I experienced the most THRILLING moment of my life so far! It was a sheer privilege to be with respected Noongar elder Dr. Noel Nannup, on this, his Noongar Country, to work with a native raptor that has been soaring over the Jarrah forest and watching humans engage with country for thousands of years. Noel named this absolutely gorgeous female eagle 'Yirrabiddi' - which in language means 'path up above' or 'path in the sky' ('yira' = up, above/sky; 'bidi' = path or trail), because of the beautiful trails this bird will leave as she moves through the sky. Noel's first mention of the name brought tears to my eyes, as it was such a perfect, meaningful Noongar title. What a piece of heartfelt magic!

Yirrabiddi was born on a large eyrie very close to my home in the Mundaring Shire, and the territory in which her parents live includes my family home. I have a distinct memory from the age of about 7 of watching the adult eagles circling high above our block, and this was fresh in my mind as I headed out to check the nest last week. Seeing a very large juvenile perched high in the the nest tree was a thrilling discovery, and I knew she was ready to be satellite-tagged. I have wanted for so long to find out more about the movements of this particular Wedge-tail family, and it was an exciting feeling today to take the first step in doing so.

Yirrabiddi's nest was over 20m high in a glorious Marri tree.
 
After scaling the nest tree and securing the juvenile eagle, I was fortunate to have the assistance of Neil Hamilton, a good friend and eagle handling mentor, who held Yirrabiddi while I took measurements, fitted her with leg rings, and attached the transmitter. Having her powerful eyesight temporarily disabled with a falconry hood kept the wedgie calm throughout the process, and she had a certain aura about her that made this tagging experience all the more special.

 

While ringing and tagging eagles it is always interesting to take note of certain details that are not necessarily easy to see when the bird is viewed at a distance. Yirrabiddi had particularly beautiful nape (neck) feathers which were fringed with blonde at their tips. This is something I have observed with only a few Perth Hills Wedge-tails (including one ringed last year), but most are uniformly golden on their head. I've seen quite a few photos of juvenile wedgies from other parts of Australia, some of which are almost white, and am always fascinated by this individual variation.


With the processing complete, it was time to return Yirrabiddi to the canopy. I scaled the rope and hung just below the eyrie, then removed her from the canvas bag and lifted her towards the sky. With talons thrust forward and a single, powerful flap of her mighty wings, she lunged upward and stood securely back on the nest. What a moment that was!


My warmest thanks to all who were involved today, especially Noel, for agreeing to be the Noongar presence I was so keen to have visit this special homeland Wailitj family, and Brendon Gough, an old Parkerville friend who also grew up in this area and was watching the eagles long before I was even born! I am also super grateful to my good friend Judy Dunlop who took the amazing photographs that solidify the memories of this wonderful experience. I am feeling incredibly humbled, and blessed to be alive. What an amazing eagle day!!

A happy bunch. My bird-banding supervisor Neil Hamilton with grandson James; Dr. Noel Nannup; Yirrabiddi, and my good friend and fellow Parkervillian Brendon with daughter Jorja.

Friday, 4 November 2016

Korung: Another Sat-tagged Eagle


Yesterday it was a wonderful feeling to deploy the second GPS/Satellite Platform Terminal Transmitter (PTT) on a juvenile Wailitj / Wedge-tailed Eagle in the Perth Hills region. Meet Korung, a beautiful female eaglet who is about 9 weeks old. As with Wailitj, the male satellite-tagged last week, she was removed from the nest for a brief period while the PTT was fitted, and while she was ringed/banded and measured. Then she was then returned safely to the canopy, which has a great view over the surrounding Jarrah forest. I am extremely grateful to the crowdfunders who supported this research, and for them I recorded a short video of Korung back on her nest which you can watch on my Facebook page here.

We were fortunate to have had Hilary Smale from ABC local radio accompany us and produce a fantastic podcast for Peter Bell's breakfast show on ABC 720, which you can listen to here. Lorraine Horsley also wrote up a piece for ABC News online, and Sarah Brookes from the wonderful, local Echo News published this article on the significance of a fantastic, positive collaboration with the Department of Parks and Wildlife, following the death of two eaglets in a prescribed burn last year, which is now helping to reduce the impact of burning on these majestic eagles.

It will be wonderful to watch the first movements of these satellite-tagged Wedge-tails as they start to explore their home territories, then wander across larger expanses of Perth Hills forest!

 

Tuesday, 1 November 2016

Inspiring Glen Forrest


Last week I was privileged to have the opportunity to attend Glen Forrest Primary School and give a talk to the entire assembly about the importance of engaging with and preserving our wonderful environment. As with all public speaking activities, I emphasised to the next generation that in order for humans to be healthy and happy, we need a healthy environment. This talk was part of a local environmental project initiated by a dedicated group of locals and school 'Mums', supported by the Mundaring Shire, who have been working hard to preserve bushland in the Glen Forest Super Block, a large remnant of native vegetation that supports a range of local native wildlife.

After the talk, I helped the students install a number of Nest-boxes in the Super Block, which will be monitored by the school to see which birds or mammals take up residence in the coming months. You can read more in the Echo News article here.

Wednesday, 26 October 2016

Wailitj Satellite-tagged


I felt quite nervous ascending my climbing rope 20 metres into the canopy of this glorious Marri tree to reach the huge Wailitj / Wedge-tailed Eagle (Aquila audax) eyrie today. It was the first time I'd climbed this particular nest, and the first time I was going to attempt to catch a chick belonging to this particular pair. It was also the first time I would be fitting a juvenile wedgie from the south-west of WA with a satellite tag, so a big part of the nervous feeling was related to excitement! The rope swayed as I neared the nest and clipped my safety line around a large branch. I wiped my brow. I could just see the top of the eaglet's head.

The nest seemed large from the ground, but its sheer size really became apparent as I stood up and peered across to examine its contents. The eaglet was a male, about 10 weeks old, and almost fully feathered with beautiful rich-brown plumage. It stood firmly, lifted its wings, and in reaction to my presence, shuffled over to the opposite side of the nest. Jill Shepherd (my PhD supervisor) and Bill Brown (an eagle scientist from Tasmania who has been helping me ring/band and satellite-tag juvenile Wedge-tails this month) kept a watchful eye on the bird from one side of the nest as I adjusted my climbing ropes, while Stuart Rae (a Scottish pal currently visiting from Canberra and also helping with eagle ringing/banding and tagging) watched the chick from the other side of the nest. Even with my go-go-gadget arms, I was unable to reach the eaglet from a standing position, so I climbed onto the eyrie and quickly grabbed its legs in a secure grip, then tucked the wings under my arms, to ensure the bird could not flap around and injure itself (or me!).


Once securely inside a handling bag, the juvenile wedgie was safely lowered to the ground. Bill's expertise in handling eagles was a wonderful help, and he held the bird firmly but gently while we took measurements and fitted the metal- and colour-rings to its legs. It was then ready to be satellite-tagged. As Jill filmed some of the procedure from close-range, I attached a 70 gram solar/Argos GPS/Satellite transmitter with a Teflon harness, which goes on like a backpack and is stitched up at the front to create a 'weak link', designed to fall off after a year or so of tracking. This method is used widely on eagles worldwide, does not cause the birds any harm, and has been approved by the relevant Australian Animal Welfare and Wildlife Licensing authorities. The eagle could obviously tell something was going on, but it remained remarkably calm during the attachment procedure.

A hood is used to keep the eagle calm during handling.

With satellite transmitter attached, the eagle is ready to go back on the nest.

With the processing complete and the tag attached, the eagle was ready to be returned to its nest. I scaled the tree as quickly as possible, sat carefully on the eyrie, and hoisted the bird back up to its arboreal home. Even after being off its nest for just under an hour, this magnificent young eagle was amazingly calm as I lifted it out of the handling bag and placed it down on the flat bed of Eucalypt leaves lining its nest. Wailitj, the ancient Noongar name for the Wedge-tailed Eagle, had been echoing inside my mind during the whole morning, and now it was time to extract it from my thoughts and speak it to the bird in front of me. To honour the First Australians and importance of keeping traditional language alive, Wailitj was the perfect name for the first South-west Australian Wedge-tail to be satellite-tagged. At that moment, I was overcome with a thrilling feeling that the GPS/Satellite transmitter was ON, and we would finally be able to follow the movements of this majestic creature from the moment it takes its first flight, throughout the post-fledging period, and (like our desert-born Kuyurnpa), on a dispersal journey across this vast continent!


I am indebted to the wonderful people who have supported me in the tracking research, particularly Jill, Bill and Stuart for their help today, and the amazing selection of crowd-funding supporters who jumped on board this 'maiden flight' earlier this year! You can see a quick video of my personal thanks, taken just before Wailitj went back on his nest, here. I can't wait to glimpse the first set of tracking data!

Monday, 24 October 2016

Flying with Matuwa Eagles


I am very privileged to have just returned from Martu Country where it's been a busy few weeks conducting the annual Wedge-tailed Eagle breeding survey on Matuwa. This recent research trip produced some really interesting findings - please visit the Wedge-tailed Eagle Tracking website where you can read more about them.

The trip ended with a bit of a disaster (my car broke down and we needed to be towed back to Perth!!), but the images of some fantastic experiences flying with eagles during the aerial nest surveys are etched into my mind, and these remind me that any pitfalls that arose during the trip were worth it to have been able to see these magnificent birds from such a unique perspective! The above photo was taken when this adult launched off a perch and flew below the helicopter.

Thursday, 6 October 2016

Owlet Trio


When Mike Lohr rang me with the good news that he'd found a Googamit / Southern Boobook (Ninox boobook) breeding in one of the owl nest-boxes we installed earlier this year, I nearly jumped out of my skin! I could hardly contain my excitement as I tied the ladder onto my roof-rack and packed some camera gear into the car. Bill Brown, a friend from Tasmania who had just arrived to help me with eagle research at Matuwa, was also excited to come along and we chatted about our past experiences with owls during the drive down to meet Mike at a bush reserve in the Perth suburbs.

As we approached the nest tree, an adult boobook peered out from inside the nest-box, keeping a half-closed but watchful eye on us. Leaning the ladder against the tree trunk was enough to cause her to launch from the box and swoop in a silent glide to perch in a nearby Banksia. As I slowly scaled the rungs, I was very excited about what I might find, and still tingling with excitement that the target species had nested in a box designed especially for it! This was the first record of owls using one of my nest-boxes, and it is always interesting to be able to have a intimate insight into the nesting habits of a less-common, nocturnal species.


What an amazing sight! THREE juvenile boobooks sat low in the nest chamber. As I snapped a few photos, the owlets gave me occasional winks and made clicking noises with their bills, warning me to keep back. It was interesting to note several regurgitated pellets on the floor of the nest-box's hollow entrance, which mostly contained insect exoskeletons, and also, to my surprise, a scatter of green, orange, yellow and blue body feathers belonging to a Rainbow Lorikeet (Tachyglossus haematodus). Several bright green and yellow tail-feathers, also belong to this species, lay on the floor of the nest box chamber.

Bill Brown lends a hand to Mike Lohr as he prepares to band one of the owlets.

After lowing the owlets down in a calico bag to Mike, I watched while he weighed, measured and banded them, took a blood sample for health analysis and collected parasites. This work is part of Mike's PhD research investigating the impacts of fragmentation on the Southern Boobook, which has been recorded as declining for the past decade or so. I was very fortunate to be given the opportunity to supply and install nest-boxes for a part Mike's project testing whether nest sites are limiting their presence in urban and agricultural areas. Breeding records inside easily accessible boxes like this one allow broods of owlets to be given health checks and marked to help collect information on factors affecting their survival - and they also allow an up-close look at some of the most beautiful young birds one can find in the bush!



Mike takes a head-bill measurement from one of the Boobook owlets.


When all the data had been collected, it was time to return the owlets to their nest. I scaled the ladder, hauled the calico bag and its precious contents back into the canopy, and gently lifted each bird out, one at a time, and lowed it inside. As I leaned inside the box, a pungent odour of ammonia filled my lungs, a result of the bed of decaying regurgitated pellets which had accumulated during the past few weeks. Seemingly oblivious to the smell, the owlet trio peered up at me and continued to blink their wonderful, wide eyes. It would only be a week or so before they would begin putting these to use, making their first flight from the nest box into the nocturnal world.

Tuesday, 4 October 2016

Three Little Pigs

 
Many people don't realise that feral Pigs (Sus scrofa) are an environmental issue in parts of the Perth Hills. In fact, there is a sector of the community who actively hunt pigs and in recent times people have been caught and fined for illegally breeding and releasing them into several catchment areas to ensure they have a constant supply of 'hunting game'. Waterways such as the Avon and Helena Rivers, and Wooroloo and Gidgegannup Brooks, are particularly attractive to pigs as they are remote, and at this time of year offer a reliable water supply and lots of food. Land management authorities such as Parks and Wildlife and the Australian Wildlife Conservancy go to great lengths to remove pigs, but as with any feral control, its a labour-intensive and ongoing battle.

While at a Wedge-tailed Eagle nest yesterday, I was delighted to find one pair were doing 'their bit' for removing pigs from the ecosystem surrounding their eyrie. I decided to write a little story about my discovery, which goes like this...

One day a small & weak Wailitj (Wedge-tailed Eagle) chick was suffering head injuries after attacks from its larger sibling, when mama eagle flew in with a sudden delivery of fresh prey: pork! One little piglet had wanted to build a house of straw, one a house of bricks, & the third couldn't decide WHAT house he wanted to build... when suddenly, a large bird of prey decided they should ALL move into a biiiiig house of sticks. So it dived down, lifted them up with its powerful talons, & carried them high over the Wandoo woodland.



"My eaglet is weak", thought mama Wedgie.
"But this food might just help save its bacon!!"

Many people had been worried about the damage feral pigs cause to the precious Perth Hills bushland, but now they knew of an amazing house of sticks where Three Little Pigs (and hopefully many more) had died happily ever after. And that is the end of the story!!

As part of my current research project on Wedge-tailed Eagle movements, I am fitting colour-rings to eagles to help identify individuals and find more information about their dispersal. This involves lowering eaglets from their nest to the ground in a handling bag for ringing/banding. Mike Lohr, an experienced bird-bander currently doing a PhD research project on Googamits (Southern Boobook owls), assisted with ringing the larger chick.
At only 3 weeks of age, the smaller one was too small to be banded, and its chance of surviving sibling attacks currently seemed slim... but we decided that if it is still on the nest when we return to check this site in a month or so, we might be able to colour-ring it then.

It was interesting to note the difference between the two eaglets - the weaker chick had damage to its crown, a result of sibling attacks, and normally chicks in this condition gradually decline in condition and eventually die. However, this one's wounds seemed to be healing well and the chick's full crop suggested it had recently been fed, so perhaps some sudden 'intensive care' from its parents will help it against the odds.

The smaller eaglet had many feathers missing from its brows, but this seemed not to be related to sibling damage, as there were no scars or evidence of bleeding.

The larger chick had well developed pin-feathers on the wings, and its wing length suggested it was just under 4 weeks of age. You can see the differences in physical development clearly in the below photo (note that the size difference is accentuated by the proximity of the more dominant chick to the camera):


 After ringing/banding and measuring were complete, we hoisted the eaglets back into the canopy and I placed them back in the centre of their massive eyrie, about 18 m above the ground. The dominant chick sat up and gazed back at me, and I was thrilled to see a hint of the yellow colour-ring on its leg, which will hopefully give a good chance of this bird being resighted at a later date.

I wonder what will be for dinner tomorrow? Maybe a nocturnal bird, like a Boobook, or perhaps more pork?!?

Friday, 30 September 2016

Eagle Breeding - Success and Failure


Wedge-tailed Eagle nests in the Perth Hills are normally built high up in one of the largest trees available, which gives the birds a good view over their territory. Large trees usually have at least one sturdy fork in which the birds can construct their massive stick platform, but such trees are not necessarily entirely stable. While checking on one pair of eagles recently, I parked at a familiar monitoring location - a roadside parking bay - and peered up to the nest with binoculars. Despite being familiar with the site, I was unable to see the eyrie right away, and I wondered if the canopy of trees in the foreground had grown up and obscured my view. After several minutes scanning, I still had no luck, so I decided to walk up to the ridge and have a closer look. Judging by observations of an incubating adult from earlier in the season, I anticipated the nest should contain a month-old chick.

While walking up the steep, rocky ridge towards the nest tree, I pondered the whereabouts of the nest, casting my mind back to last breeding season, when it was clearly visible. Why couldn't I see it? I then remembered the entire nest tree was dead, and suddenly realised what must have happened. I had a vision of what lay in front of me, and sure enough, as I neared the site, I noticed my instinct was right.


The entire nest tree, a very large, straight but entirely dead Marri, lay on the forest floor. Its rotted root-system had prized up a large chunk of earth, and as I inspected the ground, I realised the relatively wet weather this year must have made the ground soft, and strong winds (not to mention a very heavy eagle nest!) caused it to topple over. As you can see in the above image, the nest-tree still has bark, indicating it has probably only died in the last 2 years. I've noticed that mature eucalypts like this seem to be 'dropping off the perch' at an increasingly frequent rate, a result of increased stress during the hotter, drier summers associated with a changing climate.

The grim news was that I confirmed the nest had indeed contained an eaglet aged about 5 weeks, evident from its remains found amongst the mass of collapsed branches and nest lining.

Examining the remains of a 5 week-old eaglet which died when the nest came crashing down.

The eaglet's leg can just be made out in the remains of the giant, collapsed eyrie.


This was an unfortunate discovery as the eaglet was born in a productive territory with ample food, so would have had every chance of fledging. Nevertheless, such events emphasise the delicate balance between life and death, and prove that not every bird which breeds fledges chicks in the 'happily ever after' scenario that humans often perceive. They are an interesting and important part of ongoing research.

Unlike the above site, however, most other eagle nests in the hills have been successful this year, and it has been exciting to commence ringing/banding the first chicks of the season. This is now the second year of the colour-marking study which is part of a long-term research project investing the movements and survival of juvenile Wedge-tailed Eagles, which commenced last year. I have worked towards setting up such a study ever since I found the first Perth Hills wedgie nest over 15 years ago, and put many hours into obtaining the appropriate licenses from State and Federal Government departments, so it is a fantastic feeling to know the study is off the ground at last!!


I climb to each nest using rope-access techniques, and the chick is carefully secured by the talons and placed into a handling bag, then lowered to the ground. This allows us to perform all the necessary tasks beneath the tree and on a flat place which doesn't sway around in the breeze! Once inside the bag, the eaglets normally sit on their haunches until they are taken out and held firmly by an assistant.

Mick holds the eaglet while the footspan is measured.

It was brilliant to have my good friends Mick and Rianna, and their boys Jarrahn and Bhodi, helping with the first eaglets of the year. Mick has been reporting eagle sightings and assisting with monitoring of nests for many years now, so it was a pleasure to head bush with him and his family, and this also created a great opportunity for an educational activity for the next generation of ornithologists!

The first nest we visited had a single chick aged about 8 weeks. It was in very healthy condition and had been recently feeding on a freshly killed Australian Raven (Corvus coronoides), whose carcass lay on the nest cavity.


At the second site east of the Mundaring Shire, we were delighted to discover a brood of 'twins', aged between five and six weeks. These birds were in a nest built high in a dead Marri tree and had an amazing view over the surrounding Wandoo woodland. Wedgies normally lay two eggs but only rear one chick, as the second either doesn't hatch or dies in the first few weeks of nest life. After the nesting failure described above, it was wonderful to have a 'replacement' turn up so quickly!



7 year-old Jarrahn was delighted to see this female eaglet up close.

The first part of processing eaglets involves placing two metal rings/bands around the their legs: a stainless-steel ring from the Australian Bird and Bat Banding Scheme, and a specially designed aluminium colour-ring fitted with pop-rivets, coloured yellow which is unique to my Perth region study area. I have learned the method of applying such bands from Golden Eagle researchers in Scotland, where I spent time volunteering and gaining experience earlier this year, and it has been fantastic to carry on with the same type of work back home.


After ringing/banding, several measurements are taken to record the birds' morphometrics and help us determine their sex. Female eagles have a larger head and a much broader footspan than males, and this difference is apparent after the age of about one month.

Measuring the head-bill length. The long cere indicates this bird is a female.
Measuring the rear talon (halux). Juvenile talons are pin-sharp as they haven't yet been worn.

The ringing and measuring usually takes about 15 minutes, and we carefully monitor the birds to ensure they remain calm throughout. A key difference I've noticed between wedgie and goldie chicks is their personality, with the latter being much calmer overall, sitting quietly and allowing their measurements to be taken without moving much. Wedgies on the other hand sit up in a threat display to warn of any would-be predator (or scientist!) and often strike with their feet at anything that moves beneath them. For this reason, it is safer for the birds and us handlers if they are held firmly but gently during the process.

When we have recorded all the necessary information, the birds are again placed in the handling bag and carefully hoisted back to be returned to the nest cavity. The usual reaction is for chicks to go back on the nest and immediately adopt a defence posture, spreading their wings to make themselves look bigger. This is a good sign that normal behaviour has resumed, and after taking a few photos, I descend the ropes and leave them in peace.

Eagles really are remarkable creatures, and such important parts of our natural heritage. They captivate people with their majestic, soaring flight and inspire us with their almighty powers of vision and capabilities of predation. But they are often simply just there, and we don't necessarily know exactly what they (in particular, young, non-breeding birds) need to ensure their survival. It is for this reason I am driven to continuing research to find out as much as possible about their ecology, and fill knowledge gaps regarding juvenile dispersal. Where will these yellow-ringed birds end up? Keep your eyes peeled, and you might one day be able to tell me!

If you do see a Wedge-tailed Eagle bearing metal leg rings/bands, please photograph it, record the time, date, GPS location, and if possible, the 3-digit colour ring number, and contact me to report this information.