普通鳾的巢位选择和繁殖成功巢特征

Research of Nest-selection and Reproductive Success on Eurasian Nuthatches (Sitta europaea)

普通对巢位具有选择性,利用树种共7种,利用率不同,利用树洞类型有两种,啄洞利用率高,结洞低。洞口朝向在西至西偏北45°方向的树洞利用率最低,其它方向差异不大。洞口处树的直径、洞口纵径、洞内径、洞深和洞周围10m范围,树的密度5个巢位变量在利用和未利用树洞之间差异极显著(P<001),洞口横径,洞口处树干与垂直方向夹角和洞口方向90°角10m范围树的密度差异显著(P<005),其余变量差异不显著(P>005)。23巢平均窝卵数778±095,孵化率8994%,出飞率9627%。30个巢中成功巢和失败巢的11个巢位特征比较发现,洞高和洞口方向90°角10m范围内树的密度差异极显著,洞口纵径和洞口横径差异显著,其余变量差异不显著。

The nest site selection and reproductive success of Sitta europaea was studied in secondary forest in the natural protective area of Zuojia,Jilin Province from March to July in 2003.The results showed that S.europaea selected 7 kinds of trees to be their nest site among 14 broad leaved tree species.Populus davidiana and Tilia mandshuria were used the most in ratio, Salix pierrotii was the main nest tree of the bird due to their highest availability. Used two types of cavity were available in the study area,excavated cavities (EC) and knot cavities (KC).Bird selected EC was utilized more frequently than KC.Entrance direction of cavity at northwest 45° was significantly less selected than the other direction.As to EC,there were significant difference in tree diameter at cavity height (DCH),vertical diameter of entrance (VDE),inner diameter of cavity (IDC),vertical depth of cavity (VDC) and density of tree around cavity (NTC) between used and unused cavities ( P <0 01);Angles between trunk at cavity height and vertical direction (ATV),horizontal diameter of entrance (HDE) and number of tree before of the entrance (NTE) were significantly different ( P <0 05).As to KC,IDC and VDC were significant difference,the other variables did not differ significantly( P >0 05).The average clutch size was 7 78±0 95, the ratio of hatching success was 89 94% and flying out is 96 27% in 23 nests.