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Sarcocaulecent scrubland is representative of the Sonoran Desert of Baja California Sur, Mexico. In this area 92 % of its flora is shrubs and 23 % of these are endemic species, however, the ecological impact of animal production is unknown. The objectives of this study were to determine and to compare during two years the preference and use of plant species by grazing goats. Data field collections were done from June 2006 through June 2008. Botanical composition of diet and the study area data sets were used to estimate preference and similarity indices. In the studied site total plant species were 78 and goats utilized 41 throughout the study, in each collection date goats utilized 10 to 24 species. Mean similarity index was 26 % (16 to 32 %), both preference and utilization were highly variable between collection dates for each plant species. Preference by goats was not in accordance with similarity. This pattern of feeding behavior may indicate a conservative strategy of forage utilization by goats.