Please don't conclude that Gracie is a bad mom! On the contrary, she has produced seven offspring in the past three seasons, six of whom fledged successfully. As Amy states, her first clutch of eggs was taken off the bridge this year because researchers knew from past experience that the fledglings would be unlikely to fledge successfully from the bridge. They also took the eggs very early in their development in hopes that Gracie would "double clutch," i.e., produce a second clutch of eggs and also move back to a nest site on dry land. We were very hopeful when she, in fact, did move back to one of the nest sites on the PG&E building equipped with a nest cam and lay a new egg. But unfortunately, she did not produce any additional eggs and, for whatever reasons, abandoned the single egg. The fact that she even produced an additional egg in a second clutch is remarkable since "double clutching" requires that both the male and the female completely reverse the hormonal process that occurs after a first clutch is laid, and essentially "jump start" the reproductive cycle. Apparently, they weren't able to do this successfully this year. We have high hopes for next year, of course, and meanwhile we are following the development of the one chick from the bridge clutch, hoping that the egg from the second clutch will also develop successfully, and happily watching the San Jose pair whose three little ones are developing beautifully.

Neil

The Santa Cruz Predatory Bird Research Group can do a much better job than I at answering these questions. Another great resource is the Yahoo Group formed around George and Gracie's activities: http://pets.groups.yahoo.com/group/PGEfalcons/ You have to join to read the messages, but there's some great reading to be done on the site.
Thanks for writing!
Amy