Spatial patterns in relative primary productivity and gazelle migration in the Eastern Steppes of Mongolia

The Mongolian gazelle (Procapra gutturosa) of the Eastern Steppes of Mongolia shows seasonal migrations to traditional winter and calving grounds with diffuse movements during the intervening periods. We used a normalized difference vegetation index (NDVI), derived from coarse-resolution satellite imagery, to map relative primary productivity of steppes between April 1992 and December 1995. Productivity peaks were variable between years, but winter, and calving grounds had highest NDVI scores during periods of use by gazelles. Gazelle movements to these areas track shifts in primary productivity across the steppe. Diffuse movements in summer were not matched to peaks in productivity. Productivity 'hotspots' utilized by gazelles during critical periods in their life cycle should be first priority for conservation and the impact of livestock grazing on these areas should be evaluated. (C) 2001 Elsevier Science Ltd. All rights reserved.