Sandgrouse are specialists of arid regions. In the Western Palearctic and 
Middle East most of these regions have a well-recognised botanical 
uniformity placing them in the Saharo-Sindian regional zone of White 
and Leonard (1991) which stretches continuously from the Atlantic 
seaboard of the Sahara to the Thar Desert of India. It is scarcely surprising 
therefore, that many of the plant species (and, even more so, the genera 
and families) recorded by Cramp (1985) as dietary items of sandgrouse 
in these regions have a certain similarity. The crop contents reported here 
are no exception, although for P senegallus in particular there are few 
precise data and none pertaining to the plant species recorded here 
(Cramp 1985). 
Seeds of three species, Emex spinosus, Tephrosia purpurea and Asphodelus 
tenuifolius (= A.fistulosus), accounted for >95% by weight of the crop 
contents of this bird (Table 1). Although Cramp (1985) mentions several 
members of the Polygonaceae (eg Fagophyrutn and Polygnum spp) as food 
items of sandgrouse, surprisingly no record is indicated for the widely 
distributed £ spinosus. Tephrosia spp are commonly recorded however, 
especially T apollinea, as is A tenuifolius. Chenopod and grass 'seeds', 
minor items here, are also commonly recorded by Cramp (1985). The 
only identifiable plant fragments were of a species of Tribulus, a genus 
particularly prominent in arid zones. One roundish stone, c.2mm in 
diameter, was also found. 
For the seven species of sandgrouse in the Western Palearctic (and 
Middle East) food is listed by Cramp (1985) as "mostly seeds" (three 
species), "mainly seeds" (two species) and "primarily" or "predominantly 
seeds" (one species each). Since seed production in arid regions is 
especially rain dependent, and as rainfall itself can be highly variable in 
both space and time, it may not initially be surprising that sandgrouse are 
nomadic in order to exploit the best 'pastures'. Seeds, however, do not 
disappear, as any green and rain-fed desert will testify, although they 
may well become more difficult to find the longer the season of seed 
production has passed. In arid regions especially, seeds are capable of 
withstanding many years of desiccation (down to only a few percent 
moisture content) until the right conditions for germination appear. 
Could it be the desiccation state of seeds that is important to sandgrouse? 
If older, very dry seeds are harder to digest than fresher ones. Could 
nomadism be more the result of seed age than seed abundance? Anyone 
who has a chance to examine the crop contents of a sandgrouse could 
easily find out seed age by weighing seeds as quickly as possible, drying 
them out (see Table 1) and then reweighing them to calculate their 
moisture content. 
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