Red Fox with a Meal

I spotted this red fox cross the road while driving through Yellowstone National Park. It was a dreary, rainy day, but I parked on the side of the road and stalked it into the woods. When I came upon it, it was listening very carefully and watching the ground, likely for a meal. I used its intense focus on its prey to my advantage and was able to sneak within 10 meters! Before I was ready for a shot, the fox pounced and started digging and disappeared behind a tree stump. When it emerged, it had a mole and saw me and trotted into the woods. I followed, and I was able to catch the fox sitting and staring at me. I was able to get a few shots before it silently slipped in the woods for good. Perhaps the fox was a female and was heading back to her den with her catch to feed to her kits? Maybe that's why she didn't eat the mole right away...or maybe she was antsy because I was there.