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We studied the degree of variability and repeatability of egg size in clutches in the context of clutch size and reproductive output of a double-brooded Desert Finch population (Rhodopsiza obsoleta). The within-clutch coefficient of variation (CV) was significantly greater in first (mean = 1.92, 95% CL: 1.54-2.30) than in second broods (mean - 1.24, 95% CL 0.94-1.55). Repeatability estimate for egg volume was smaller for first (0.51, 95% CL: 0,26-0.77) than for second broods (0.74, 95% CL: 0.52-0.90). Simultaneously, mean clutch size was bigger for first (4.61, 95% CL: 4.31-4.92) than second broods (3.69, 95% CL: 3.40-3.98). However, the number of nestlings and the number of fledglings were not different between first and second broods. The observed differences in clutch size and the within-clutch variation for egg size between first and second broods lead to a similar overall breeding output. These results point to a possible strategy applied by females during the two egg-laying periods in the breeding season, and depend on the fast-changing and extreme environmental conditions in arid habitats. (C) 2008 Elsevier Ltd. All rights reserved.