Osprey Cam update: First egg to 21 days old Posted on June 19, 2014 by Ben Wurst Young osprey develop so fast! by Ben Wurst, Habitat Program Manager First egg was laid on April 19. They were incubated for 38 days, which is slightly more than the average of 35 days in NJ. The first two eggs hatched on May 29th, and the third on June 1. 5-7 days old. Sleepy… Feeding time is non-stop with ospreys! Downy and body feathers start to emerge at 14 days old. Today marks 21 days old (for the oldest two young). They’re now very active in the nest and like to check out all the cool nesting material mom & dad used in the nest.