^Eagle perfection! Stunning in every way Evelakes!!
Seriously, with shots like that I'd never look twice at a 7Dii (or any other camera for that matter).
I'll state an amateurs view of Sigma since you brought it up. Currently in the room right now 40+ lenses and only one Sigma. I've had quite a few over the years and was never never ever satisfied with any all but one, the 35mm 1.4. The only Sigma that was sharp (to my eye and without docking, and MFA, and lots of fiddle-faddle was the 120-300mm but woefully heavy, truthfully it was a great lens but wore me out toting it about.
Your eagle captures with s Sigma state just the opposite of what I just said...lens camera combo? Nah, I think it was/is the photographer (me).....I've just had much better luck when off-branding (versus staying Canon bodies with Canon glass) with Tamron.
Now where did you go for these multiple passes of the eagle? I've got to visit you and carry some of your gear for you!