Kakadu has seen several invasive species threaten the native habitat, particularly in recent decades. Introduced fauna including the Water Buffalo, wild pig and more recently, the Cane Toad have had major effects on habitat. Invasive weeds include "Mimosa pigra", which covers 800 km² of the Top End, including vast areas of Kakadu, invasive paragrass displaces the native food of much of Kakadu's birdlife. "Salvinia molesta" has infested the Magela floodplain. Brumbies also inhabit areas of the National Park, including Yellow Water.