33-year-old Golden Eagle – longest recorded ringed golden eagle in the world.

Way back in 1985, my diary for 30th June records that I was monitoring golden eagles in the north Inverness glens with my daughter Rona, home from Uni. We climbed to an eyrie near Cannich, which I had monitored for many years, and ringed a single eaglet – ZZ0005. I also attached two small yellow wing tags but the eagle was never identified alive. In fact like most ringed eagles nothing more was heard of it – until out-of-the-blue, I received two emails yesterday. One was from the BTO ringing scheme and the other from Gabriela Peniche, a PhD researcher on golden eagle health at the Dick Vet at Edinburgh University.

The remains of this eagle had been found near Loch Assynt in Sutherland on the 10th August and sent to the lab. It was thought it may have been dead for about 6 weeks and a male. The cause of death was unknown, but there was bruising in the skull and a suggestion of starvation. This is a ‘safe’ area for eagles, free from illegal persecution. My view is that a likely end to a very old breeding adult, of either sex, is to be defeated or killed during a challenge by a young adult to take over a nesting site. That’s how nature works for long-lived raptors.

The BTO Ringing Scheme longevity data gives the present longest recorded life of a ringed golden eagle as just over 16 years – a Kielder Forest chick 29th June 1991 found dead in the Scottish Borders 7th August 2007. In some ways this bird’s death stimulated the South of Scotland Golden Eagle recovery project started this year. In Europe, the Euring database records longevity records for two Swedish ringed golden eagles at 31 years and 32 years, while 23 years is the oldest record in the United States. So ZZ0005 at 33 years appears to be the oldest recorded ringed golden eagle in the wild in the world. There is a record of a captive one reaching 46 years, while very expert fieldwork on breeding pairs of golden eagles on the Isle of Skye by my old friends Kate Nellist and Ken Crane gave an annual adult survival rate of 97.5% suggesting that some adults could reach 40 years of age.

From its recovery location, it may have been the local breeding adult male living in a home-range some 90 kilometres north of its natal site. I know those local eyries from my eagle fieldwork in the 1970s and 1980s. By 2010 Doug Mainland had ringed 18 young at this location since 1990 (when ZZ0005 was five years old). On 17th June 2010 I visited the eyrie with Doug, Derek Spencer and Lorcan O’Toole, who collected one young for the Irish Reintroduction Project. The other eaglet, a male, was satellite tagged and named Suilven: to read more click here. There’s just a chance that ZZ0005 may have been its male parent. This eaglet ranged widely when young, even briefly visiting Skye but when sub-adult returned to an area just east of its natal nest. In the spring of 2015, when Suilven was 5 years old the transmitter fell off (as they are meant to do) and we guess he may still live and breed in that area of Sutherland. It’s lovely to think what a couple of emails can do and how worthwhile was that hike up the mountain in 1985. Bird ringing at its best.

Ranging widely in Cairngorms National Park

Mackay is a six year old female and has not yet found a mate and nest. Between 7th May and 7th June she has ranged over 2100 sq kms. Early in May she was mainly along the eastern Angus/Aberdeenshire border and on May 15th she moved to low ground 3 kms east of Cairn o’Mount for two days. On 13th May she flew north-west and was over Abernethy Forest/Cairngorm at 4pm on 12th May and by evening was on the Monadh Mor. She then settled in an area near An Sgarsgoch until 6th June when she flew south to Ben Vuirich in Perthshire to 8th,


Keeping to two separated locations

Loyal is now 4 years old and she has continued to alternate between two areas in Sutherland, but is not breeding yet. She continued living around Cape Wrath mainly along sea cliffs south of Lighthouse. She completed a round flight to Merkland and back on 2nd and 3rd May. She left Cape Wrath at midday on 16th May, passed over Kinloch at 1pm – 900 metres altitude and 32kph- and reached her other favoured area SW of Kinbrace in the late afternoon. She there in an area of 30 sq kms through to 8th June.

Ranging widely in Sutherland and West Ross-shire

Globe has ranged in an area of 3000 square kms with a north-south distance of 90 km. In early May she was in an area south and west of Ben Klibreck; 12th May at west Alladale and then wandering on 14th -15th May with a big flight north past Ullapool to Canisp and onto Cranstackie, near Durness. On 17th she moved south-east to Borrobol, near Kinbrace.  Then headed south to Braemore Junction area on 17th May and stayed in big area around Ben Dearg until early June, when she flew north to an area south of Elphin 3rd – 8th June.  Five years old but no sign of breeding yet.

Roxy breeding

Latest news from GPS transmitters suggests Roxy has young – in the last month she has used a home range of 17 square kms, with max distance away from nest of 6 kms SW on 12th May.

Ranging west Sutherland

Globe was south of Loch Urigill at start of month, then SE of Scourie on 7th December, as far north of Arkle on 20th; at Christmas was around her parents’ home range, at one time just 4 km from her original nest.

As usual

Two non-GPS signals from the Foinaven SPA

Usual two area locations across Sutherland

Loyal was in home territory from 5th to 8th December in the Moine/Loch Eriboll area, then went to the Kinbrace area until 17th. She then headed NW, roosted just SW of Rhiconich on 18th/19th December, and spent Christmas period around Cape Wrath. A range of 1200 square kms

Ranging is Deeside and Angus

Mackay was just SW of Glen Clova on 4th/5th December and roosting in a wood north of Bridge of Dee on 6th and 11th December. Taking in non-GPS locations the range was 875 square kms

ranging in home range

Roxy’s amazing transmitter is still working and sending data; on 9th and 24th December she made flights south to the valley NW of Broad Law