Only two chicks?

ONE of the three falcon hatchlings being watched by the world on The Courier-Mail's Frodocam has vanished without a trace.

Three chicks had hatched on the inner-city penthouse nesting ledge of urban peregrine falcons Frodo and Frieda – two of them yesterday.

But at some stage yesterday one of them – probably the second hatchling – disappeared.

Queensland Museum raptor expert Greg Czechura said today he was baffled.

A check through the day's Frodocam logs shed little light on the mystery.

There was no sign of a crow or other predator on the webcam.

"In any case, it would have to be a pretty game predator – and a pretty quick one – to go anywhere near the falcons' nest," Mr Czechura said.

Throughout the day, Frieda was barely away from the eggs or the chicks, and showed no signs of distress. "She looks very relaxed," Mr Czechura said.

He said that if a chick died, the parents would sometimes leave it, or they might eat it or throw it away. None of the images or video captured from Frodocam yesterday showed any sign of that.