While shooting at Stow Lake on Saturday, I ran into Nancy DeStefanis of SFnature.org who spotted the new chicks in the nest seen below. She says they are about a week old. You can see the adult on the right behind the tree branch.
See the complete series at diary page 4-2-2011 at raptor-gallery dot com
Also at the lake there is a Great Horned Owl nest and there are four young quite a bit further along in growth. Here is one and its parent.
Meanwhile the Peregrine Falcons downtown have hatched two with two eggs yet to hatch.
Check out the pages and good birding to all.