人工巢箱条件下的大山雀巢捕食

于2004—2008年在次生阔叶林中,采用悬挂巢箱的方法对大山雀的巢捕食作了研究。结果表明:不同年龄巢箱的被捕食率显著不同,新巢箱被捕食率最低,第2年被捕食率最高,第3年下降很大,第4年又略有上升。被捕食巢的窝卵数极显著的低于未被捕食巢的窝卵数。影响巢捕食的主要生境因子为巢箱高度和巢上盖度,其次为灌木的密度和高度。

Nest predation of Great Tit inside nest boxes

Hanging nest-boxes were used to study the nest predation of Great Tits in secondary broad-leaved forest from year 2004 to 2008. The results showed a significant difference between nest-boxes of different age groups with a chi-square value of 34.55 (P < 0.01, df = 3). The predation rates were the lowest in the new nest-boxes and the highest in the second-year nest-boxes. There was a large decline in predation rate in the third-year boxes and a slight climb-up again in the fourth-year boxes. This is consistent with the hypothesis of G. A. Sonerud et al. (1993): "The nest predation rate increases as the age of nest-box increases, as a result of long-term spatial memory of the predator". To verify the hypothesis that Great Tits could adjust the clutch size after their nests are predated, we conducted a t-test to compare the clutch size of predated nests to the non-predated nests. With a t-value of 3.6488, the clutch size of preyed nests was significantly smaller than non-preyed nests (P < 0.01, df = 16). Habitat factor analysis (PCA) of prey nests revealed that the height of the nest-boxes and the degree of nest site coverage were the main habitat factors impacting the nest predation, followed by the density and height of shrubs as secondary impacting factors. Key words: Great Tit, nest predation, clutch size, habitat factor.