利用天然树洞繁殖的五种鸟的巢位特征及繁殖成功率

摘要

对吉林省左家自然保护区次生阔叶林中的大山雀(Parus major)、沼泽山雀(Parus palustris)、普通(币鸟)(Sitta europacea)、白眉姬鹟(Ficedula zanthopygia)和灰椋鸟(Sturnus cineraceus) 5种利用天然树洞繁殖的次级洞巢鸟进行了巢位选择和繁殖成功率研究.本研究中共发现141巢.五种鸟对树洞类型的选择存在种间差异,普通(币鸟)不利用裂洞,沼泽山雀不利用啄洞,其它3种鸟对3种洞均有利用,但有一定的倾向性.对5种鸟9个巢位变量的比较中,只有洞口方向差异不显著(p>0.05),其它8个变量均差异显著(p<0.05),该结果说明5种次级洞巢鸟对巢位的选择具有其各自的需求.洞口横径、洞口纵径、洞处树直径、洞内径、巢距地高是巢位选择重要变量,它们决定不同种类对树洞的利用.巢损失多数出现在产卵之前和孵化阶段,44个繁殖失败的巢中有35个在这两个阶段损失.大山雀的巢成功率最低,灰椋鸟的巢成功率最高.5种鸟的孵化率都超过90%.人为破坏和动物捕食是繁殖失败的主要原因,占总数的61.4%.洞巢鸟巢位选择中的重要变量影响繁殖成功.普通(币鸟)繁殖是否成功受洞口横径和巢高影响,沼泽山雀受洞口纵径、树胸径和洞内径影响,大山雀受洞口横径、巢高和洞内径影响,灰椋鸟受洞内径和洞深影响,白眉姬鹟受洞口纵径、巢高和洞口夹角影响.失败巢的洞口横径多大于成功巢的洞口横径,失败巢的洞深、洞内径小于成功巢的洞深、洞内径,成功巢的巢高高于失败巢的巢高.靠近地面的巢较容易损失,38个繁殖失败巢中有21个巢高低于2.5m,只有2个高于4.5m.%This study documents the nest-site characteristics and reproductive success of Ashy Starling (Sturnus cineraceus), Tricolor Flycatcher (Ficedula zanthopygia), Great Tit (Parus major), Marsh Tit (Parus palustris) and Nutchatch (Sitta europaea) breeding in natural cavities in the secondary forest of the natural protective area of Zuojia, Jilin Province in China. We found 141 active nests of five species of secondary cavity-nesting birds (SCNBs) at the study site during the breeding season in 1996.There exist significant differences between the five species of SCNBs in selecting cavity types. Nine nest-site variables were tested to see if they varied significantly among the 5 species. The results showed that only the compass orientations of nest entrance are not significant (p>0.05). But all the remaining eight variables are significant (p<0.05). The results indicate that the 5 species of SCNBs select nest-sites with their own nesting requirements. The horizontal diameter and vertical diameter of nest entrance, diameter of tree at cavity height, inner breadth of the cavity and the nest height above ground are important variables in nest-site selection and are predictive of species occupancy. Most of the nests that failed occur before the laying and hatching stage, as 35 out of 44 failed nests loss during these two stages. The nest success of Great Tit is the lowest and Ashy Starling is the highest. Hatching success among the five species of SCNBs' are at high level, all exceeding 90%. Depredation (included by man and animals) is the main cause for nest failure, accounting for 61.4% of total failure nests. SCNBs' reproductive success is influenced by important variables in nest-site selection. Reproductive success of Nutchatch is influenced by HDE and NH, Marsh Tit by VDE, DBH and BC, Great Tit by HDE, NH and BC, Ashy Staring by BC and DC, and Tricolor Flycatcher by VDE, NH and CA. The horizontal and vertical diameter of nest entrance of failed nests are bigger than those of successful nests, and the depth of the cavity and breadth of the cavity of failure nests are smaller than those of successful nests. Distances from ground level of successful nests are higher than those of failure nests. The nests close to the ground are more easier to lose, 21 out of 37 failure nests were under 2.5 m above ground level, and only 2 nests above 4.5 m from ground were lost.