On the gravel beach along the Buha River in the Tianjun County section of Qinghai Lake National Park, two Tibetan foxes are caught in a lively food tussle: their fluffy tawny-gray fur presses closely together, their pointed snouts lock onto the prey at the same time, their front paws instinctively reach toward each other, and even the stubbornness of refusing to let go shines through their squinted eyes.