For the last few years I've been enjoying watching and photographing a pair of splendid ospreys who nest nearby on Salmon Bay (in Seattle). Shortly they'll head south for the winter, but for the last week or two they've been fishing from a tree near the Ballard Locks. I think salmon were sparse earlier in the summer, but seem to have picked up a little recently, and the ospreys have been able to fatten up a bit for the long flight ahead. Today the male was determined to get one of a shoal of big coho milling around the entrance to the fish ladder beside the Locks. He dived five times while I watched, and was finally rewarded with a sizable fish. After one of his unsuccessful dives he flew directly over me to return to his perch. This is the best photo from that sequence - the first is almost the full frame, the second a crop to show him up close. He's just been in the water, dripping wet, and no doubt a bit ticked off at having come up without his hoped-for dinner.
Taken with the AF-S 300 mm f/4 and TC-1.4, ISO 640 1/2000 at f/8. Even with the D850's autofocus (I use AF-C, d9) I find I'm lucky if I get every second or third frame in focus when a bird is flying towards me and up close. It's mostly my inability to follow the bird's motion with the focus point as it rides up and down with each wing beat, but I also find that this is the hardest scenario for the AF system to understand and react to - I tend to get a lot more focused claws and tail-feathers than beaks and eyes. So this is a fortunate one.
One fun thing for Nikon folk is to notice is that his eye seems to have a six-bladed iris - like some of those really old, classic Nikkors! (Interestingly this shape, and the brown flecks in his iris, are real and persistent, a distinguishing feature of this particular bird).
Cheers, John