Saturday, 19 May 2007

When will the eggs hatch?

Today is a chilly, very windy day with rain showers and also day 12 of the female Blue Tit incubating eggs in our Camera Nestbox. The question now is - when will they begin to hatch? Well, this is Scotland and it has definitely been a much cooler May than last year. I have no records of my own to make estimates so I have referred to other Nestboxes on the Web. It seems hatching begins between 12 and 16 days so in day terms that would be between today, Saturday, and Wednesday.


My guess is now going to be for Tuesday as the weather has been so cool. I originally thought tomorrow might have been the day. The pictures above show the eight eggs and our Blue Tit female sitting in the nest cup at 9am this morning.

Hatching has a process that is really quite fascinating. It appears that chicks call to each other and to the parents from within the egg! This helps co-ordinate their hatching – although they won’t actually hatch together. They use a tiny ‘egg tooth’ on the bill tip to break the shell and then struggle until they push the two ends apart. So the process goes from cracking to forcing then to actually breaking out. I wonder if we will see any of this live on the screen – I hope so.

No comments: