what are you trying to do with this study? The proportions are off in a couple places, did you do an underdrawing or go straight to painting? This looks like a digital piece, so tweaking the proportions with a few cut and pastes should do the trick. Be careful to have the tiger look in the right direction, right now he's tripping balls, not getting ready to strike
I think after that you should break out some hard brushes and get some detail and hard shadows/lights going. These decisions will also help you get your values right. I think you did a good job on the chick, the rest has pretty harsh contrasts both in saturation and brightness.
Lastly, and this is most obvious on the tiger:
If you go from shapes, do the whole shape and not only light and dark. Do a hearty stroke to rough out the whole arm and then go back an add shadows and light areas on top of your own shape and compare to reference and the original piece.
The lesson should not be to trying to recreate a painting but to try and apply the techniques used to your own art. I would like to see you do the same scene from a different angle
Keep it up!