Ringing of Peregrine Falcons

Here is some information on the 3 peregrine chicks, ringed today:

Chick 1
Left leg: Green 75
Female
Weight: 830g

Chick 2
Left leg: Green 76
Possible male
Weight: 600g

Chick 3
Left leg: Green 77
Female
Weight: 880g

This year the last chick hatched on 7th May, some five days after the first and four days after the second chick. Such a long gap is unusual in peregrines. Thus when ringed and measured today the ages of the chicks were 17, 21 and 22 days. The larger two chicks are females but it is difficult to be certain of the sex of the much younger and smaller chick, though we suspect male. Hopefully we will have a better idea as he/she grows. They all looked healthy. The wing and tail feathers of the older two chicks are now 2-3 cm but will grow rapidly. The white, downy appearance will change as their feathers grow.

It’s not that unusual for an egg to fail to hatch. It could well be infertile. Or it can be due to a crack in the shell sustained by an adult being clumsy & leading to an infection, or an egg wasn’t properly incubated for a time & the chick died.