If you have a moment, I can show you how to tell a fledgling great blue heron from an adult. The quickest way to tell the age is to check the head! The adult has a head crowned with a white stripe that is enclosed in a black stripe and often a plume or two off the backside of the crown. The fledgling has a solid gray-capped head. It has no plumes. There is a big color difference in the body feathers too. Light pearl gray youngster and adult deep slate gray. There are other differences but for standing at the riprap and trying to decide is that a baby or is that an adult remember: it’s pretty much all in the head.