Sheep graze differently from cattle, nibbling anything palatable down to the roots but avoiding the tough, tussock-forming moor grass that slowly took over. Cattle use their long tongues to rip up the moor grass, and their hooves break the surface of the ground, allowing seeds to get established, increasing biodiversity. This conservation grazing has had an impact. The number of whinchats, for example, almost tripled in the five years after the cattle arrived.