Tuesday 7 April 2020

White-tailed Eagles on the Move

Tuesday 7 April

White-tailed Eagles Haliaeetus albicilla with their eight foot wing span are Britain's largest bird of prey.  So why would I be mentioning these birds on a Spanish birding site?  Well, this morning I received an email from one of our readers, Don Mooney confined to his Kentish home rather than out here where he would prefer to be undertaking some birding and photography, informing me that the surviving four White-tailed Eagles introduced to the Isle of Wight last year have taken it upon themselves to start the greater exploration of their new home to see just what is out there beyond their new island home.  All four birds have left the island to go a wandering far and wide albeit one made a rather "rapid" return home.

So what do we know about these birds?  We know that take over five years before reaching maturity and consider breeding but that in these formative years they do wander about to really get to know their extended territory before, usually, returning to their natal destination, release area in this case, to actually take up breeding residence.  So a long, hard struggle to survive these early years, especially with the indiscriminative killing of many raptors by other vested interests.

The above "wanderings" this past week or so have taken the birds almost directly over, usually at a relatively low height, the homes of two of my three sons and a pair of grandchildren as they traversed both Wiltshire and Berkshire.  Not only that, the birds then continued northwards and even included Rutland Water, my local patch just ten limes west of my Stamford home from which I make regular visits, so I might possibly, had I been there, have seen the birds from my back garden!  And there would certainly be no mistaking these grand raptors for Buzzard let alone the resident Red Kites.  

More news of the birds, their history and development can be found on the "Roy Dennis Wildlife Foundation" site which can be directly accessed by CLICKING HERE.

Now read the informative and delightful report published yesterday by the Wildlife Foundation:

Eagle wanderings

We may be living in very strange times, but it is reassuring that the natural world continues as normal. As I write four newly-arrived House Martins are zipping around over my back garden and I only have to log on to the web to watch a pair of Ospreys already incubating eggs at Rutland Water.
Thankfully technology is also allowing us to keep track of the movements of the four juvenile White-tailed Eagles that we released on the Isle of Wight last summer, in partnership with Forestry England. After a winter when all four birds were extremely sedentary, often living in very small areas and proving highly elusive, the recent longer days and warmer weather has prompted a clear shift in behaviour. All four of the birds have started wandering away from the places on the Isle of Wight, and Oxfordshire/Buckinghamshire that they favoured in the winter and their satellite transmitters have proved invaluable in monitoring these movements and understanding how young White-tailed Eagles learn the landscape.
Perhaps unsurprisingly G393, the male eagle who spent the winter in Oxfordshire and Buckingham, was the first to make a significant move. On 20th March, six months after arriving in Oxfordshire, he flew 71 km west, aided by a stiff easterly breeze, into Wiltshire and roosted in an area of woodland between Swindon and Malmesbury. Next day he was on the move again and headed north-west, flying at altitudes of up to around 500 metres towards the Severn Estuary. He paused for over two hours at Slimbrdge WWT reserve and then headed across the estuary to the Forest of Dean where he was seen by a number of observers, including Ed Drewitt who photographed the bird passing over his garden. That night G393 roosted in a wood beside the River Wye in Herefordshire having flown another 80 km during the course of the day.
G393 flew from Oxfordshire through Wiltshire, Gloucestershire and Herefordshire on 20-22 March

The young eagle meandered 26 km north along the Wye and the Lugg valleys in Hereforshire on 22nd March, but then made a much more concerted move the next day, flying 97 km north-east to Staffordshire, flying at relatively low altitudes for much of the day, but apparently going unseen. He remained in Staffordshire until the morning of 2nd April, favouring an area of woodland near Keele and making only short local movements during the day, likely feeding on carrion and rabbits; behaviour much more reminiscent of how he had spent the winter.
After a week in Staffordshire G393 headed east on 2nd April, skirting around the north side of Derby and then the south-west of Nottingham, again flying at altitudes of less than 200 metres. At 15:50 he was at an altitude of 400 metres directly over Melton Mowbray in Leicestershire and half an hour later he arrived in the North Arm at Rutland Water.
Rutland Water is a place certainly capable of supporting breeding White-tailed Eagles in the future, and G393 spent all day there on 3rd April, favouring a small area in the North Arm near Barnsdale, where he was seen chasing Egyptian geese. In the Netherlands the goslings of feral geese are a favoured food item, and the birds are also capable of catching sick or injured adults.
After a day at Rutland Water, a stiff southerly wind encouraged G393 to head north again at 10:30 on the morning of 4th April. He headed north-east through south Lincolnshire, and at 13:40 was just west of Mablethorpe. He then followed the coast north and was photographed by Owen Beaumont from his garden near Louth at around 14:25. Eventually G393 stopped 10 km south of Grimsby in an area of scattered trees and woods, having flown 80 km since leaving Rutland Water.
After some short local movements, G393 resumed his flight north at 09:30 yesterday, crossing the Humber from Barton-on-Humber at 10:20. An hour later he was perched in a wood north of Beverley. From here it seems certain that he caught sight of another of the Isle of Wight birds, G318, who was passing to the west, because the two birds then flew north together for at least the next 17 kilometres. While G318 paused in an area of woodland, G393 continued north into the North Yorkshire Moors and eventually settled to roost in an area of woodland in the east of the National Park having flown 123 km.
After spending a week in Staffordshire, G393 (orange line) flew to Rutland Water on 2nd April and then north through Lincolnshire on 4th. That same day G318 (blue) followed a remarkably similar route north through Lincolnshire and both birds roosted just south of Grimsby.  The next day they flew north together for at least 17 km through Yorkshire.

G318 was undoubtedly the most sedentary of the three birds that spent the whole of the winter on the Isle of Wight. In February, for example, she lived in an area of less than 1km². However, that changed on 16th March when she crossed the Solent and flew north-west across the New Forest to north-east Dorset. She spent all of the next day in a wooded area near Sixpenny Hendley, and then made her way slowly north into Wiltshire on 18th.  After two days in an arable area west of Salisbury, G318 flew to the Wiltshire-Somerset border near Longleat on 21st March and next day she completed an amazing 101 km circuit of Somerset. She passed over Westhay Moor in the Somerset Levels at around 9:00 before continuing west, almost to the coast. After pausing in an arable field east of Burnham-on-Sea she headed north towards Weston-super-Mare and then east over Banwell and Sandford. At 14:40 she was just 3.5 km south of Chew Valley Lake, flying south-east at an altitude of 432 metres. Two hours later she was back on the Wiltshire border.
Female eagle G318 flew a 101 km circuit of Somerset on 22nd March

After her excursion around Somerset, G318 returned to the arable area west of Salisbury and remained there until 31st March, likely feeding on carrion with the local red kites and favouring a small area of less than 1 km². She made a return flight back to the Somerset border on 31st March and 1st April and then next day flew 56 km north-east to Berkshire. After spending all day in arable fields between Newbury and Hungerford on 3rdApril, a stiff southerly breeze encouraged G318 to head north at 11:00 on 4th.  By 14:00 she had already flown 104 km and was passing just to the east of Daventry at an altitude of 521 metres and at 14:20 she was a few kilometres west of Rutland Water at an altitude of 474 metres, the second White-tailed Eagle to be present in the county that day. By this stage G393 had already left Rutland and was three hours and 90 km ahead of G318, but she headed north on a similar track through Lincolnshire and then settled to roost just 10 km north-west of him, in a wood between Grimsby and Caistor having flown a remarkable 263 km during the course of the day.
Yesterday, like G393, G318 also continued north, crossing the Humber at Winteringham at midday and then joining up with her compatriot from the Isle of Wight just north of Beverley. She paused in a wood near North Grimston for an hour in the early afternoon, but then resumed her flight across Yorkshire and arrived in a Forestry England woodland in the North Yorkshire Moors National Park just before 16:00 having flown 108 km.
Male G274 is another of the birds that remained on the Isle of Wight throughout the winter, other than for a six-day excursion into the South Downs and New Forest from 8th-13th February.
Like the other birds, G274’s behaviour began to change in mid-late March and on 27th he crossed the Solent and completed a 125 km circuit of the New Forest and River Stour valley before returning to the Isle of Wight. Then on 1st April he again headed across the Solent, from Culver Down to Hayling Island, and flew east along the Sussex coast, passing over Bognor Regis, Worthing and Brighton, at altitudes of 500-600 metres. Once east of Brighton G274 cut inland, passing to the north of Eastbourne at 14:45 and then heading north-east, just inland from the coast, crossing into Kent at 16:00 and eventually settling to roost in a Elhampark Wood, a Forestry England woodland near Stelling Minnis, after a day’s flight of 225 km.
Next morning, on 2nd April, G274 flew south-east to the coast at Dover and was perched on the shore for an hour from 8:30 to 9:30, perhaps eating. He then followed the Kent coast north and again paused on the shore at Sandwich and Pegwell Bay NNR for over two hours from 11:20. When he resumed his journey G274 headed west, skirting around the north side of Canterbury and the roosting in woodland 6 km south-west of Faversham having flown 103 km during the course of the day.
On 3rd April G274 reached a maximum altitude of over 100 metres as he resumed his journey west, passing to the south of Gillingham and then north of Sevenoaks and Reigate and then on across the woodlands of the North Downs in Surrey. When he settled to roost, he had flown 106 km during the day.
It was now apparent G274 was on his way back to the Isle of Wight, and sure enough, when he set off at 08:10 he headed purposefully south-west, despite a stiff headwind. Four hours later, he had covered 63 km and he was flying at an altitude of 37 metres over Hayling Island. He then headed back across the Solent and returned to one of his favoured areas of the Isle of Wight. He had flown 524 km.
G274 completed a 524 km loop around south-east England between 1 and 4 April

As Project Officer, Steve Egerton-Read reported in his December blog, G324 spent all winter on the Isle of Wight, often in the company of G274. Her first flight away from the Island was a brief two-day excursion into Sussex and Surrey, but after roosting in woodland near Goodwood on the night of 25th March, she returned to the Island the next day. However, on the morning of 4th April she crossed the Solent and was photographed by Amy Robjohns from her garden near Fareham. A brisk southerly wind appeared to be encouraging G324, and she passed Winchester at 13:00. Two hours later she was flying north-east through Cambridgeshire at an altitude of 720 metres and that night she roosted in arable farmland just north of Lakenheath Fen RSPB reserve in south-west Norfolk after a flight of 245 km. Yesterday she continued north-east for another 65 km and reached an area of private land close to the North Norfolk coast.
G324 was photographed by Amy Robjohns over her garden on 4th April

As this report shows, the data we receive from the satellite transmitters provides a fascinating insight into the movements of the young eagles during a period that is key in them learning the landscape. Interestingly, the recent explorations of the Isle of Wight birds mirror the behaviour of four satellite tracked juveniles in the Netherlands, who have dispersed into Belgium, France and Germany in recent weeks. You can view that data on a fantastic interactive map, here. Young White-tailed Eagles are known to explore widely in their first two years, before usually returning to their natal area (or in the case of the Isle of Wight birds, the release site) as they approach breeding age. This is exemplified by the fact that, at present, there could be as many as four or five continental birds wandering around the UK, including a metal-ringed bird that is thought to be from Sweden. It is possible that this particular individual has been present since winter 2018/19 when it was seen in the New Forest and other sites in Hampshire. What our satellite data can’t show us is whether the Isle of Wight birds have encountered any of these individuals on their travels – but it certainly seems likely.

The young eagles have wandered widely since late March

It Is going to be very interesting to follow the young eagles progress over the coming weeks, and we will be providing regular updates on their movements. We are also working to collate sightings of continental birds to try and determine exactly how many of these birds there may be around southern and central England at present. With this in mind, if you are lucky enough to see a White-tailed Eagle over your garden, please send us the details using our new online reporting form. Given the way these birds readily travel over towns, villages and even cities, there is a chance of seeing one wherever you live – so keep looking up, but please do stay at home and stay safe.

Many thanks to the Roy Denis Wildlife Foundation for putting this excellent information in the public domain.

For further, on-going information us the following link and, presumably, amend the date as necessary.

http://www.roydennis.org/2020/04/06/eagle-wanderings/ or simply go to the sites's Home Page and check under Latest News.

Check out the accompanying website at http://www.birdingaxarquia.weebly.com for the latest sightings, photographs and additional information

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