Nice start and I know you're having fun. Birds are wonderful portraits, IMO. Keep at it.
The first one really ought to be in portrait, not landscape layout, I think. I'd crop off the right side.
The second one would be much nicer if you cropped closer and didn't have that stick right behind his head, but I know how that can be.
The Great Blue Heron in black and white? Why? Black and White does not make an image more artsy. If you don't like it in color, B&W won't make it better. Personally, I see no reason ever to do birds in monochrome. Half the wonder of birds are their colors. Again, I'd crop much closer.
The last is my favorite, but again, in my opinion needs to be cropped closer. Nice job in catching the eye glint. Nice sharp image too.
Overall, great job. Keep them coming. You're going to need a nice Canon 400 f/5.6 or something soon.
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Cheers, Craig
Equipment in Plan via Profile