Abstract:In birds, sibling competition of nestlings could be controlled by feeding position of parents on the nest edge, and asynchrony hatching might exacerbate this competition. In the meantime, the nestlings can get more food for their growth and survival by competing for advantageous positions in the nest. From April to August in 2013 and 2014, 22 nests of Rufous-tailed Shrike (Lanius isabellinus) in Gansu Anxi Extreme-Arid Desert National Nature Reserve had been found, and we videotaped the feeding behavior of these nests from 1-day-old nestling until fledglings to check the parents feeding positions and nestlings food-receiving sites. Meanwhile, we measured body weight of all nestlings every two days using electronic scale (precision of 0.01 g) to calculate the growth curves. All data analysis was made in SPSS 19.0. Specifically, Chi-square test was used to find significant difference among four feeding positions of parents, and one-way ANOVA was used to analyze the relationship between the hatching order of nestlings and the frequency which the nestlings occupied linear or bilateral sites in the nest when they got food, and the relation between the hatching order of nestlings and the average times of nestlings getting food. Our results showed that the parents feeding positions were predictable and mainly gathered at 1 (n = 13, proportion > 50%) or 2 sites (n = 9, addition proportion > 60%) (Table 1), and the nestlings in the straight line of the parents feeding position got more food than those in the two sides (n = 22, P < 0.001, Table 2). Furthermore, the hatching order of nestlings was not correlated with the frequency they occupied linear (df = 4, F = 0.211, P > 0.05, Fig. 2) or bilateral (df = 4, F = 0.068, P > 0.05, Fig. 2) positions in the nest, and there was no significant difference in food getting frequency among the nestlings with different hatching order (df = 4, F = 0.090, P > 0.05, Table 3). The growth rate of nestlings’ weight in different hatching order did not show significant difference (df = 4, F = 0.637, P > 0.05, Table 4). The parents of Rufous-tailed Shrike preferred to feed in a straight direction with fixed feeding position to control the sibling competition of nestlings, but the shrike siblings were in week competition, we suggest that it was associated with the short-term food richness of the breeding areas, and the trade-off between begging and food intake of the nestlings themselves.