The female osprey is known to have laid 55 eggs
The UK's oldest known breeding female osprey has returned to Scotland for the 20th consecutive year.
The female bird has amazed staff at the Scottish Wildlife Trust's (SWT) Loch of the Lowes wildlife reserve.
It was spotted landing on its usual nesting site, known as an eyrie, on Tuesday, having completed a 3,000 mile migration from West Africa.
At an estimated 25 years old, it has reached three times the average lifespan of an osprey.
Emma Rawling, SWT's Perthshire ranger, said: "We are truly amazed at the tenacity and endurance of this particular female osprey.
"Defying her age, she has made it back to us again and from initial sightings she looks like she is in remarkably good condition."
It is expected that the female osprey's breeding partner, a male osprey identified with a green leg ring, will arrive within a week.
This resident male will then chase away any other males before breeding.
The female osprey is known to have laid 55 eggs, 46 of which hatched into chicks that left the nest.
Ms Rawling added: "We will be watching the nest with bated breath to see if our female can hatch any chicks again this year."
Throughout the breeding season the eyrie will be visible via a nest camera on screens in the visitor centre and on the trust's website.
A team of about 70 volunteers watch the nest 24 hours a day to safeguard any eggs from thieves and poachers.
About 200 pairs of osprey breed in Scotland.