On the exposed plateau pikas never stray far from their burrows but even so, squatters will move in given half a chance. While ground peckers and snow finches can be a nuisance they're worth tolerating, because they provide a valuable early warning system. The bizarre Tibetan fox. The pika's nemesis. When stalking, it keeps below the skyline perhaps helped by its curious body shape. But why the square head? In summer, the Tibetan plateau heats up drawing in warm wet air from the south but the water never arrives. As the moist air approaches it's forced upwards by the Himalayas and condenses into huge rain clouds.