The Elkhorn Slough National Estuarine Research Reserve has a group of dedicated volunteers who (among other things) work hard monitoring the health of the slough. One of the bird monitoring programs at the Reserve checks on the health of nesting raptors.
This photo of three Great Horned Owlets was taken by Reserve docent Shirley Murphy on 4/14/08 using a digiscope with a Nikon ED scope and Nikon Coolpix P4.

May 2, 2008 at 4:42 am
As of April 26th, our Great Horned Owl triplets had “branched,” meaning they had jumped from the nest to successive branches nearby, but their flight feathers are still not fully developed. When their wings are able to support the weight of their bodies, they will finally take to the air. Our team is also following closely the nearby nest of Red-tailed Hawks “Tony” and “Carmela,” who last year fledged three young as well.