This is a very good first oil painting in my humble opinion. The only problems I see are that the birds beak and eye look a little small and the eye looks a little too far forward. The snow doesn't quite work for me either, and I think it is because of the hard edged shape that it creates. It just doesn't look fluffy. I think that either some 'puffy' edges and some small shadows in the white area would fluff it up good.
I would suggest making a model of the scene by using a big bowl of mashed potatoes and spreading them all around your studio. Observe how the light behaves from different angles and try to duplicate that without slipping and falling down. :roll: (Just a little humor there in the last bit) :shock:
Give a man a fish and you feed him for a day - Teach a man to fish and he will sit in a boat and drink beer all day! Joe V.