The UK’s oldest breeding osprey may finally have become infertile, heartbroken wildlife workers feared yesterday.
The 29-year-old raptor, affectionately named Lady by rangers at the Loch of the Lowes nature reserve near Dunkeld, Perthshire, returned to her nest at the park at the end of March making it a record 23rd year.
She broke records by laying her “miraculous” 70th egg, however wildlife reserve workers admitted that they are “very worried” none of this year’s clutch will hatch.
Out of four eggs that were laid, there is now hope for only one and ranger Emma Rawling said it is very likely that it is unviable. Forty days is the upper limit for successful incubation, and the last egg to be laid reaches that milestone tomorrow morning.
One of Lady’s eggs was stolen by a crow. Ms Rawling said: “Laddie (Lady’s partner) had been incubating the eggs but then flew off to chase another bird.
“In the short time he left the nest, one of the eggs was stolen”
The other three have been repeatedly left to go cold when the male bird, expected to take over from Lady when she is fishing, abandoned his post.
On Sunday, he left the the eggs un-incubated for an hour and a half, seriously risking any embryonic chicks.
Ms Rawling added: “There are two other possible reasons why the other eggs have failed to hatch.
“The most likely answer is that the eggs are infertile, which is hardly surprising due to the age of the osprey.
“The other answer is that they have been damaged in the crow attack, but there is no evidence of visual cracks.”
If the eggs do not hatch, staff at the Lowes will continue nest protection watch until the female naturally gives up incubating and then remove the eggs under licence and study them for clues. In 2011 this took 70 days. All the unhatched eggs analysed so far have proved to have been infertile.
Wildlife lovers around the world are able to watch the Osprey on Scottish Wildlife Trust’s webcam. If the egg had hatched and the tiny, fluffy grey chick had successfully left the nest, it would have been Lady’s 51st chick to have fledged.
It is unknown how many of Lady’s eggs have hatched in her lifetime but she has had 50 chicks leave the nest double the number the average osprey mother fledges.