Advice on metering needed,....

If your hawks are turning out dark it probably means they're sitting in the shade. I think the best advice I can give you is to catch the hawks when they're sitting in sunlight like below:





The second best piece of advice is to crank up the exposure compensation when faced with a dark hawk against a bright background. But this will blow out the sky and maybe everything else except the hawk - the photo won't look good. On my A77 I have exposure compensation assigned to a dial so it's real quick to change. Can you do that with your A57?

The third thing is to try flash with a Better Beamer. I haven't tried this yet but I've seen some nice photos taken with it.

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Lance H