Expert: Roger Lederer - 6/29/2007

Question
A couple of days ago a pair of cardinals started building a nest in an ornamental tree right next to our screened in deck.  I was excited, but thought they needed to know that we were there so if they wanted to change their location, they'd be able to before completing the nest.  I walked out on the deck and they both started "yelling" at me and finally flew off, not to be seen again that day.  The next morning at the crack of dawn, they were back with a vengeance.  I went outside again, they yelled and flew off and I went back inside.  This time, they came right back and kept building.  Anyway, to make a long story short, they completed the nest and the female was sitting in the nest yesterday morning and didn't leave when my husband walked out on the deck, but when I got home for work, I couldn't see her in the nest.  I hoped that she was just so far down in the nest that I couldn't see her, but this morning I saw the leaves on the limbs shaking a little and Mama was there, kind of poking around and then flew off.  I saw the pair fly into a cedar hedge not far from our house as I was leaving for work this morning, so I think they are probably building in there.  I've been thinking about it all day and am wondering:  1.  Did she abandon the nest after she had laid eggs?  
2.  If so, was she destroying her eggs this morning?
3.  Why did she finally decide to leave when she knew we were there the entire time she was building?

Thank you for your time.

Answer
Cardinals and other birds will build nests in busy areas but when they discover it is too busy, they might, as happened in this case, abandon the nest and build elsewhere. They will not destroy their old eggs or nest, just abandon them. They are instinctive and do not think, so they do not plan ahead.