Hi Peter,
First off, this is a great series of photos of a wonderful bird. The first two especially really catch my eye. They are sharp, well-composed, well-timed.
You ask for critique, and the only suggestions I can make would be in the post-processing. On my monitor (calibrated) these images all appear a little 'cool' and the shadows could be lifted a little. Here's a quick alternate version of the first image (placed side by side with the original, for easier comparison), with small tweaks to color balance, shadows, saturation and sharpness
Not a huge change, but to my eye, it really brings out the best of what you've captured.
Edited to Add: looks like I increased the noise in the background a bit - this could be dealt with as well, but you get the idea here.