Okay, here we go.
First off I would like to say I like that big-boned/fat/bold wolf on the left of the viewer. His chubbiness is very eye catching for me.
The only thing I have to say about him is that his tail doesn't seem quite attached to his bum.
The wolf in the middle seems to be missing a chest that canines have. I don't know if he's just really skinny, but that's how he looks to me. Also, I know his eyes are looking to the side and his head is titled but it just seems wonky to me. I'm not quite sure how you'd go about changing that, just goof around a bit I guess.
The wolf on the viewers right has this smug look that I really adore. It says 'So you think you can take me huh?' the way I'm seeing it.
One thing that might have added a bit more impact on this piece is if you gave the wolves some shading appropriate to their surroundings. They just seem so light compared to the forest behind them.
The way you drew the wolves got a sense of their personalities across to the viewer. I think it's safe to say the wolf on the right is a bit more of a loner simply from the way he's facing away from the group.
Keep up your great work and I look forward to see more from you,