Expert: Roger Lederer - 5/13/2005

Question
Hi,
Eastern Tennessee here.  A house wren has decided to make a nest in an artificial flower planter hanging on my front door.  She's laid 5 eggs I'd guess about 5 days ago, if not longer.  Each time we come and go, she flies out (sometimes zooming our heads in irritation) and doesn't return for awhile.  I was wondering if our interruptions are affecting the incubation of the eggs, since obviously she isn't staying on them for long periods except maybe during the night.  Does she have to stay on her eggs for them to hatch?  The weather has been in the 70-80's here.  I have since moved the hanging planter next to the door so atleast it's stationary but, of course, she still flies in and out when we pass by and doesn't return soon after.  

Answer
It could very well be that your interruptions are disturbing the incubation of the eggs. Once incubation begins any significant change in temperature will kill the eggs. She has to keep them within a close range of warm temperature for them to hatch, so the less you disturb her the better. If it's a hanging planter, I suggest you move it to someplace she won't be disturbed so often. For more information on wild birds, see www.ornithology.com. Roger Lederer