|Greentings from the Critique Club
Yippee! Another bird person. I very much enjoyed going through your portfolio. You have some good bird pics there. I hope y ou don't mind if I try to give you some tips.
As with people, please don't cut off the feet of your subject. It's okay, if it's a head & shoulders shot, but not if most of the bird (except for the feet)is there. Then, especially with a white bird, bracket your shots. It's fairly easy to do with a Canon and I suspect a f6.3 would have given you good definition of those feathers.
Only because I really like what you are doing here am I going to get picky here, and go in depth with this one. You have a splendid capture of this bird, handling its prey. Think about giving it a bit more room (not much but some) to toss its head to swallow the meal. The egret is boxed in pretty tight in all directions. Uncomfortable for the egret and unsettling for the viewer (who doesn't know why he's unsettled, so he just votes lower)
I'm really pleased you used the 300mm lens on this, you can get some good wildlife with that lens, especially if you can use at least a monopod (or equivalent).
I'll look forward to seeing some top images from you.