UK’s oldest osprey lays its 56th egg

The old female osprey at the Loch of the Lowes has a new mate.© Neil Macdonald

April 2010. The UK's oldest breeding female osprey, which returned to the Scottish Wildlife Trust's (SWT) Loch of the Lowes wildlife reserve last month for the 20th consecutive year, has astounded wildlife experts once again by producing her first egg of the breeding season.

The bird is 25 years of age which raised doubts about its fertility, but she was spotted protectively hunched over an egg by wildlife watchers on the SWT's osprey nest cam. These images are also streamed live to a big screen at the SWT's Loch of the Lowes Visitor Centre, where visitors have been flocking since the famed bird returned on 23 March.

Extraordinary longevity
Osprey's live an average of eight years and are estimated to produce 20 eggs during that time. The lifespan and reproductive abilities of this individual osprey are considered ‘remarkable' by wildlife experts.

Emma Rawling, the SWT Perthshire Ranger appointed to protect the osprey during the breeding season thanks to funding from SITA Tayside Biodiversity Fund, said: "We are jumping for joy here at Loch of the Lowes. This individual bird is truly a wonder of nature.

This is the 56th egg she has produced, and so far 46 chicks have successfully fledged the nest over previous breeding seasons.  Photo credit © Scottish Wildlife Trust

56 eggs and 46 chicks have fledged
"The osprey faced persecution in the early 20th Century and was very nearly driven to extinction by 1916. But our old girl seems determined to do her bit to help repopulate the species. This is the 56th egg she has produced, and so far 46 chicks have successfully fledged the nest over previous breeding seasons.

New toyboy
"Since 4 April, we have been watching her use her extensive experience to train up a new young male mate. Identified thanks to a green band marked ‘7Y' around his ankle, this 10-year-old male was initially a bit confused about his role in the breeding process. We have watched our female show him the ropes, involving calling out repeatedly in displeasure to entice her young mate to work harder to please her. To complete his duties in breeding, male osprey must provide food for the female as she sits on the nest, bring sticks to maintain the nest's condition, and protect the nest from other males, known as interlopers.

Usual mate missing
"Now that we have an egg, the pair bonding behaviour between the two will increase, but it might not all be smooth sailing. If the usual mate of our osprey returns we could witness a battle in the skies as our resident male will try to chase away the young male and take his place in rearing any young. However, as the days pass by it is becoming more likely that we won't see our resident male. We fear he has perished during the 3,000 mile migration from West Africa."

SWT's Loch of the Lowes Visitor Centre Assistant, Fiona Hutton, said: "The exact journey and destination of an osprey might be one of the last mysteries of our natural world. While we cherish the return of our osprey for the breeding season, many individual ospreys are not tracked over winter when they migrate to Africa. As such, we often don't know what happens to these magnificent creatures when they fail to return to their breeding ground.

Satellite tag appeal
"At Loch of the Lowes, we are appealing for support to raise money to buy satellite tags for at least one of our osprey this year. An SWT volunteer will be cycling 1,000 miles from Lands End to John O'Groats to help our appeal. Donations can be pledged at www.justgiving.com/Toby-Green. Local public house, the Perthshire Arms, has also kindly donated the proceeds of ‘Osprey Ale', a brand of beer which was created and named after our resident female."