Tuesday, April 15, 2014


It appears that incubation is now in full swing. I was asked about why they were ignoring the eggs a couple days ago. I found this explanation on the Boise peregrine page. Based on this, it appears we will only have three eggs this year. I hope Bob Walter's stops by to comment on this. Happy Tax Day.

Typically, the falcons do not begin incubating until the third or fourth egg arrives so that all the eggs hatch about the same time. Otherwise, the bigger, first-hatched chick would have an unfair advantage at feeding time over the smaller, last-hatched chick. You will see both adults sitting on the eggs at times over the next few days but incubation does not begin in earnest until the laying period ends.

The eggs are capable of withstanding temperatures below freezing. The chicks do not develop much inside the egg until incubation begins. Occasionally, the eggs will appear to be left alone for short periods but, even when the adults are out of camera range, you can rest assured that at least one is always nearby to protect the nest.

Mom, serious about incubation.


Anonymous said...

I see this morning there are 4 eggs. I can't stop watching the webcam! It is so cool to see these amazing birds up close

Emily said...

I saw 4, too!! So exciting!! I love watching them. So great.

Anonymous said...

From my notes (of which I have many) -

2012: 3rd deposited/detected egg date = Ap. 17 ... 1st detected hatch = May 20, so 33 days
2013: 3rd deposited/detected egg date = Ap. 17 ... 1st detected hatch = May 22, so 35 days

2014: 3rd deposited/detected egg date = Ap. 13 + 33-35 day incubation period (I recall using 30-32 days in the distant past) yields the estimated date for first detected hatch this year as May 16-18 RW