By using e-Science information technology, an investigation was made on the hatching behavior of brownheaded gull (Larus brunnicephalus) in the Hongjiannao of Shaanxi Province, Northwest China from May to June, 2014. The diurnal hatching rhythms at different hatching stages were as follows. At daytime, the time of exchanging hatching at the early, medium, and late stages of hatching averaged 7.88±1.08 (n=39), 3.11±0.19 (n=65), and 3.17±0.22 (n=42), the changes of sitting nest direction averaged 27.75±2.04 (n=39), 23.37±0.91 (n=65), and 20.06±1.46 (n=42), and the times of turning eggs over averaged 27.13±2.02 (n=39), 21.11±1.11 (n=65), and 22.39±1.78 (n=42), respectively. At night, the times of exchanging hatching averaged 5.00±0.89 (n=39), 1.32±0.11 (n=65), and 0.95±0.05 (n=42), the changes of sitting nest direction averaged 14.37±1.72 (n=39), 10.95±0.86 (n=65), and 6.62±0.84 (n=42), and the times of turning eggs over averaged 11.25±1.08 (n=39), 8.47±0.77 (n=65), and 5.33±0.55 (n=42), respectively. On the days with strong wind or heavy rain, there existed significant differences in the times of exchanging hatching, the change of sitting nest direction, and the times of turning eggs over at the same hatching stages, as compared with those on fine days. The time intervals of exchanging hatching by the parents were mainly at 04:00—10:00, and 12:00—14:00. At the late stage of hatching, the duration of sitting nest by the parents was as long as (713.29±40.62) min (n=42). It was suggested that the parents controlled the egg temperature via regulating the diurnal hatching rhythm to assure the normal development of egg embryo during daytime and night. At the same time, incubation rhythms of brownheaded gull were compared with those of sympatric relict gull.
