A researcher who found wedge-tailed eagles could soar to extraordinary heights, has revealed the birds of prey stay within clearly defined territorial areas or 'home ranges'.

But a juvenile eagle will travel far from the nest, with one clocking up 15,000 kilometres in a year as it flew across Western Australia.

Simon Cherriman began tracking the movements of three eagles at Lorna Glen near Wiluna in the Goldfields in 2013.

He used GPS satellite transmitters which were fitted to the backs of the birds.

Earlier this year, the data showed that the birds were flying at heights of up to 6.5 kilometres, possibly due to thermal air currents in the region.

Mr Cherriman said the tracking also showed that the adults, named Wallu and Gidjee, restricted their flights to their home ranges, an area that an adult breeding pair of eagles occupies.

"Although you can observe birds, and think that pair lives there, unless you're tracking their detailed movements, you don't actually know where they move to," he said.

"They have a fixed home range, they stay there for 12 months."

The two were not a pair and came from different territories.

"We found that the home ranges were about 45 square kilometres for Wallu and about 25 square kilometres for Gidjee which was a lot smaller than we predicted because in the arid zone where they live, typically the food is very low," Mr Cherriman said.

"A home range is essentially an area that overlaps with the resources that the eagles need to live and breed so the less food that's in the landscape, the bigger the home range they need to take in to have all their needs met."

He said he expected the home ranges would be easily 100 square kilometres but they were half that.

"It's almost like there was an invisible fence going around it [the range] and they were restrained in that area although obviously they weren't," he said.

"What we showed with the detailed information from the transmitters is it's essentially a three dimensional dome because eagles fly very high.

"It's like a property, like your backyard; I guess the human equivalent is if you live on a half an acre property and someone puts a tracker on you, you might spend most of your time in the office, but then you walk around your property, you might go to the very back fence occasionally, but you're essentially living on that one block."

From the desert to the ocean and back again

That is in stark contrast to the behaviour of Kuyurnpa, the juvenile eagle, who left Lorna Glen in March this year.

"Within a fortnight, she was almost at Broome and had seen the ocean and that in itself is incredible to think that a bird seemingly born in the middle of nowhere can in a few weeks travel to the coast," Mr Cherriman said.

"She wandered south-west along the Pilbara coast, has gone straight back to her natal territory and passed over it without dropping in to say hello.

"Her odometer reads about 15,200 kilometres, at this point; she's travelled over two thirds of WA, she's crossed into South Australia, rested there, crossed the Great Victoria Desert twice."

A similar pattern of behaviour has been seen in a juvenile Golden Eagle, their closest relative.

Simon Cherriman holds wedge-tailed eagle on purple blanket in the Goldfields ( Gillian Basnett )

"It went crazy and wandered all over the place in the first year, and then in its second year, it contracted its range by about a fifth, right back to closer to where it was born, and then in its third year, it actually paired up and bred with another bird only a couple of breeding territories from where it was born," Mr Cherriman said.

"It's probably similar with wedgies - you know, they explore the whole state, find out what the landscape's like, find out where all the other birds are hanging and as a younger bird not yet ready to breed, suss out maybe where there might be a few vacancies in real estate, and as time goes by, they might settle down."

Mr Cherriman has been fascinated by eagles since an early age.

"I grew up in the Perth Hills and spent a lot of time out in the bush walking around, looking at birds in particular and was very interested in climbing trees, and finding birds' nests," he said.

"I found an eagles nest in the national park when I was 15 and I hadn't seen one before but I recognised what it was straight away just because it was so huge.

"It was in the same area where I had a tree house at the top of a marri tree and I used to sit up there a lot on the weekends and see the eagles soaring above my head.

"That nest was so huge that I could see it from a kilometre away."

He and his parents would often see them soaring above the house.

"I can distinctly remember one time lying outside and watching them, and just watching them going up and up, and gradually disappearing over the horizon, sort of having a boyhood dream - imagine if you could follow where they went and know how high they went."

Now that Mr Cherriman has been able to answer that, he would like to expand his research and track more eagles in both Perth and the Goldfields.

"One of the things I really want to investigate is mutual exclusivity because they live in such a concentrated home range, how does that fit in with their neighbours?" he asked.

"Is there literally an invisible line on top of the mountain that is their boundary or is there any overlap with where they move so you can only find that by tracking multiple birds simultaneously."

Mr Cherriman has just completed a film, Where Do Eagles Dare?, on the tracking of the birds of prey.

To find out more about his work, check out Mr Cherriman's website.

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