MAY 20 2016: Eaglet is about 65 Days old - watch for helicoptering/branching
Visit to the nest this morning for only about 20 minutes from 8:50 AM. Eaglet is about 65 days old. Flapping wings but no branching or helicoptering observed during my limited visit. Based upon ground observer reports of the eagles' behavior, we believe that the first egg hatched on or about March 16. Counting backwards 5 weeks (35 days) establishes February 10 as the approximate day the first egg was laid. This is also borne out in retrospect, based upon suspicions of observers who reported behavior of the pair on or about that date.
Therefore we may assume that the surviving eaglet is about 65 days old. Referring to the summary of past broods, the first eaglet fledges at an average age of about 75 days (range of 62 to 86 days). Therefore we should expect its first flight very soon with branching and helicoptering beginning about a week sooner. These statistics are derived from our limited experience at this one nest (with a different female parent) and are highly variable.