THE KUISEB RIVER AS A LINEAR OASIS IN THE NAMIB DESERT

The importance of the Kuiseb river as a linear oasis for larger mammal s in the Namib desert, Namibia, was investigated over a period of thre e years. Following seasonal flooding the river dries rapidly confining consumable water to irregularly spaced pools which decrease in number and surface area as the dry season progresses. Compared to the lower sections of the river more water and less vegetation are available in the relatively inaccessible upper parts of the canyon, and vice versa. Based on direct observations and tracks at waterholes more mammals vi sit the lower than the upper sections of the river. Indications are th at the pronounced seasonal influx of gemsbok Oryx gazella into the riv erbed, presumably from the surrounding dune fields, is primarily dicta ted by the availability of water. The riverine habitat of the Kuiseb i s therefore a resource critical to the survival of at least part of th e central Namib ungulate population.