Then just a week or so ago, I spotted this in our grapevine:
The following day, I walked toward the nest again, this one in the backyard, and both cardinal parents were near the area.
To my excitement, it was confirmed to me that this was a cardinal nest and eggs.
Yesterday, I thought I saw one more egg in there, carefully spying on them before my Spanish class students arrived. I may have seen wrong, as I didn't want to interfere.
This morning, the inevitable happened. Mother Cardinal was no more. Her body was picked half-clean by the merciless little Cooper's Hawk.
I saved a few feathers, and watch to see if the father will take over incubation...but I doubt that he will. The fathers only rarely spend any time on the eggs under normal circumstances, from what I have read.