I shot the above images with a 500 f4 on a Wimberley head, but usually in flight they are too agile for me, and I just can't pivot the large lenses fast enough to keep them in the frame. I think the 200-400 might work, but I suspect the Tamron 150-600 will work better because it is so much smaller, shorter and lighter than my EOS 200-400.
The few hunmmers we get here at home are pretty nervous, and don't tolerate one getting closer than 20-25 feet or so, before they skedaddle. I can sometimes capture them through a window, but I just never find images shot through glass windows pass muster to my eye.
I enjoyed the video of the lady shooting them up close through a window pane. Maybe my window panes are inferior quality glass. 😕
On a side note, I just submitted for a price quote to sell an EOS 1DX body with the Canon GPS attachment to mpb.com. I rate the body in excellent condition... any interest? I may not get a price today due to the ceremony for President Bush.