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Habitat selection by resident houbara bustards introduced outside the species’ ’normal’ breeding range in central Saudi Arabia was studied during the summer 1994. Relatively well-vegetated terrain with a low density of tall (>1 m) shrubs was the preferred daytime habitat. At night houbara roosted in relatively bare sites or, on moonlit nights, foraged in habitats with relatively low vegetative density. Plant species richness was similar at sites intensively utilized by houbara and at randomly selected sites. However, vegetative density was greater at utilized sites than at random sites. Phenological diversity, specifically the availability of plants with green shoots and flowers, appeared to be the primary factor motivating houbara choice and was directly related to the distribution of rainfall. Densities of tenebrionids and spiders were higher in utilized than in random habitats, but the overall number of species and abundance of surface-active arthropods was similar. Sampling technique limited interpretation of the importance of arthropods in habitat selection, however. (C) 1997 Academic Press Limited.