dunes from crossing the river. Between 1977 and
1981, Ward monitored the extension of the linear
dunes into the bed of the Kuiseb River by using
repeated theodolite surveys tied to fixed survey
points. Two zones were recognized: one west
of Gobabeb between Swartbank and Rooibank
(Fig. 1) where dune advance was negligible, often
less than 0.04 m yr−1; and a second zone between
Swartbank and Natab, where rates of advance were
more rapid, peaking at 1.85 m yr−1 close to Gobabeb
(Ward and Von Brunn 1985). Nevertheless west of