The heron was indeed weak. He was very thin and dehydrated -- not all that uncommon for first-year birds. Many birds have a tough go of it their first year, once they've fledged and left their nest and parents behind. Hunting or foraging for food isn't always easy when it's a recently-acquired skill, and birds can consequently suffer emaciation and even death in their first year of life. Herons, being as big and tall as they are, are often more noticeable in this weakened state to the human eye than, say, a warbler. A sickly-looking heron, who may be dragging his wings or hanging his head, is pretty hard to miss. As a result, we see quite a few herons come into Wildlife Services in this particular condition.
The heron was initially tube-fed a high-protein, nutritional liquid diet as to not shock his weakened system with whole foods. Since he took the fluids well during his first few days here, we now have the bird on solid food -- fish, of course -- and he's happily snacking on about 36-50 live fish each day. See this heron eating his lunch (and hear a raven in the background!) in the video above.
You'll notice in the video the heron has the option of walking behind a privacy screen of sorts that we've set up for him. It's just a sheet hanging over a perch in his enclosure, but it's enough to afford him a bit of privacy -- as if camouflaged -- so that he feels less exposed, especially when we enter his enclosure to replenish his food. Herons in the wild often try to blend in with their surroundings.
You'll also notice the heron's wings droop a bit. Although there are no fractures in the bird's wings, for some reason his wings seem to be a bit floppy and hang to his sides. We'll continue to monitor his wings for signs of improvement.
If the heron's progress toward recovery continues, he'll eventually be moved into our flight cage where he can rebuild his flight muscles before being released back into the wild.