Expert: Bluebird Bob Walshaw - 6/9/2010

Question
Hello,
    I recently had a pair of house finches successfully raise 5 eggs in a hanging basket on my front porch (gerbera daisies).  Another pair had just started laying eggs in the basket next to it on June 1st.  The mother bird laid 4 and was always seen sitting on the eggs (easy to see from my living room).  Today, I noticed there seemed to have been a traumatic incident to the nest - mama was nowhere to be seen, the nest was up on its side in the basket with 3 remaining eggs, 1 egg was broken open (no yolk or anything else visible), and multiple large feathers (perhaps wing or tailfeathers?) were by the nest - I'd say at least 8-10, almost like they'd been pulled out in a clump. I tried to gently re-situate the nest so she could incubate it, but there has been no sign of her all day.  Is there anything else I can do to help the situation?
Thanks for any advice,
Pam

Answer
Not much that you can do. It sounds like an attack from one of the alien killer house sparrows (actually a weaver finch, and our small native birds have no defense against its heavy finch bill and aggressive ways). A snake would have swallowed the eggs, and House Wrens just puncture eggs and throw eggs and young out of nests. If the female is still alive she will probably not return after being attacked. Birds have many predators which is why they try to raise so many young. Predators get the weak, sick, slow and the dumb, and help to keep the species strong. One pair of Bluebirds can raise 15 or more young in a season, and if they all survived we would be up to our hips in Bluebirds!