Legend has it that at least six ravens must be kept at the Tower of London or the kingdom will fall.
But the loss of one is gloomy enough news for Ravenmaster Christopher Skaife, originally from Dover, who says he will be taking time to mourn the death of the Tower's "queen raven" Merilina.
Merlina, who has been at the Tower since 2007, has not been seen for several weeks, and Mr Skaife told the BBC he fears she has passed away.
"I know so many of you lovely folk will be saddened by this news," he said in a social media statement. "None more than me. Please excuse my absence for a few days."
Speaking to Radio 4's Today programme he said Merlina was a "free-spirited raven" and had left the tower precincts on many occasions, but he added: "I’m her buddy and she normally comes back to us, but this time she didn’t. So, I do fear that she is not with us any more.
“Just before Christmas, before we went into the lockdown, we were putting the ravens to bed, and she didn’t come back.”
According to one legend, Charles II is believed to have first decreed that a flock of ravens - sometimes known collectively as an 'unkindness' - should be kept at the Tower at all times.
When numbers fell to just one bird, Winston Churchill ordered the flock should be increased to at least six.
Merlina's loss means there are currently seven ravens in residence, so the kingdom is safe for now - barring any calamities at the parliament of rooks upriver at Westminster.