Paul

There was an interesting paper on inbreeding in black robins showing both positive and negative effects.  I can't remember the citation. The "secret sex life" and small amount of this inbreeding behavior might help maintain crow social bonds in some ways that might offset the deleterious genetic problems that might occur.  While it may seem very strange to humans, it might "work" in some ways for crows and other animals.  Extra-pair fertilization is not at all surprising to me in birds, humans and many other so-called monogamous animals, and could definitely add some "genetic diversity" to these close-knit groups.  A risk-benefit analysis played out over the long evolutionary history of such behaviors . . .

I have been to Terre Haute, IN a few times in the winter and witnessed the roosting activity there.  As a kid, there was a large grackle/"blackbird" roost in my neighborhood.  Except for a little bit of odor, we never were too worried about it. From what I know about the Terre Haute crows . . . it does not seem to be well-tolerated by many (most?) locals there.

I am around here, and I think I would be where the big grackles live as well.  Some of the boat-tailed grackle photos in the SnapID were tough!