Oldest osprey 'Lady' lays 59th egg at Loch of Lowes Published duration 13 April 2011

image caption The female osprey has returned to Loch of the Lowes for the past 21 consecutive years

An osprey thought to be the oldest breeding female in the UK has laid another egg at a Perthshire wildlife reserve, it has been announced.

The bird, known as Lady, has returned to the Loch of the Lowes reserve near Dunkeld to breed for more than two decades.

However, her fertility had been under doubt as she is now 26-years-old.

Anna Cheshier, Scottish Wildlife Trust's Perthshire ranger, said it was "remarkable" to see eggs on the nest.

She said: "Ospreys live an average of eight years and are estimated to produce 20 eggs during that time.

"Producing 59 eggs over 21 consecutive breeding years makes her an incredible specimen of the bird world."

'At risk'

Staff are hoping the egg will successfully hatch in about five weeks time to become the osprey's 49th chick.

The nest is now being monitored round-the-clock to keep Lady, her mate and their egg safe.

Ms Cheshier said ospreys had nearly become extinct in the UK after facing persecution.

She added: "The birds and eggs are still at risk from wildlife criminals and egg thieves.

"Until the eggs hatch, we will watch on as our female osprey incubates the eggs, while her mate occasionally takes a turn during daylight hours.