Pop-Up flash.
I used it regularly on my D200 and found it invaluable at times. I often draped a white tissue over it to soften the effect.
My only issue with the PUflash is that with *some* lenses, perhaps most notably the 18-105, if the lens hood were mounted, an ugly shadow was created, even with more distant subjects and longer local lengths. Not usually an issue with an SB800 or similar. Otherwise a very useful feature.
Also thanks for the Stork webcam link, added to my collection of bird webcams! This is a link to a local Osprey webcam at Foulshaw Moss very close to the Kent estuary, part of Morecambe Bay.
https://www.cumbriawildlifetrust.org.uk/wildlife/cams/osprey-camIt's tending to be a bit unreliable, if the link won't connect, then reloading the page and clicking the start arrow usually fixes it. Some remarkable scenes with the chicks developing and both parents feeding and protecting them in an exposed location with various predators in the vicinity.