Cracker: The eggs are rare because rheas only lay in warm weather

And while 12 free range hens' eggs may cost you £2, a dozen of these would set you back £72.

For this comes from the rhea, a flightless South American bird whose eggs are growing in popularity as a delicacy in Scotland.

At Corrie Mains Farm in Mauchline, Ayrshire, four rheas are attracting attention from visitors intrigued by the sight of a creature usually more suited to foreign climes.

Anne Smillie, who runs the farm, said: "The rheas are South American ostriches.

"They love it in Scotland. They are very hardy birds and, although they have a shed to sleep in, they choose to sleep out at night.