窝雏数处理对两种雀形目幼鸟生长的影响

基于 1 997～ 1 999年野外实验 ,对高寒草甸小云雀和黄嘴朱顶雀两种雀形目鸟的窝雏数进行增减处理。结果表明 ,对照组的幼鸟生长率和离巢体重都大于增加组 ,说明窝雏数增加后 ,幼鸟质量下降。随着窝雏数增加 ,这两种幼鸟生长率显著下降 (小云雀 :r =-0 965 ,P =0 0 3 5 <0 0 5 ;朱顶雀 :r =-0 82 8,P =0 0 2 2 <0 0 5 )。窝雏数改变对小云雀幼鸟出飞重影响不显著 (r =-0 41 8,P =0 5 2 8>0 0 5 ) ,而对黄嘴朱顶雀有显著的影响 (r=-0 90 1 ,P =0 0 1 4<0 0 5 )。

Effects on Nestling Growth by Brood Manipulation in Two Passerine Birds

The experiments were conducted at the populations of Small Skylark( Alauda gulgula )and Twite( Acanthis flavirostris ) in Haibei Alpine Meadow Ecological System Station, the Chinese Academy of Sciences, in northern Qinghai Province from 1997 to 1999. We performed brood manipulation experiments by adding or removing one, two, or three nestling in selected nests having similar hatching time, while keeping the original number in other nests to serve as control. The results show that nestling growth of Small Skylark and Twite are affected by adding nestling. The control groups' nestling growth rates and fledging mass had the enlarged broods worsened the young's quality decreased.