You nailed the exposure in here and I like the low angle. Would balance the composition by adding a bit to the left and cropping a bit off the bottom to keep the 2:3 ratio.
Aesome details Josée. The fresh snow looks great (as does the ptarmigan). Ofer's comp suggestion is good, but I like it as is too. I guess I'll have to go in about 10 years... :-)
What an amazing looking creature, and you exposed him so well. I agree with Ofer on a tad more on the left and a tad off the bottom. I love the hightlights throughout the picture. They really add to the scene.