白尾地鸦的巢址选择

Nest-site Selection of the Xinjiang Ground-Jay(Podoces bidduphi)

2017年4和5月,在位于新疆塔克拉玛干沙漠南缘的和田地区民丰县对白尾地鸦(Podoces bidduphi)的巢址选择进行研究。共记录白尾地鸦巢12个,测量了巢参数,用Mann-WhitneyU检验分析巢样方与对照样方的差异,用主成分法分析影响白尾地鸦巢址选择的主要因子。结果显示:1)白尾地鸦巢多筑于绿洲边缘的柽柳(Tamarix)灌丛,巢距地面高(109.1±13.2)cm,巢深(8.5±0.5)cm,巢厚(3.8±0.4)cm,内径(13.9±0.9)cm,外径(21.6±1.3)cm;2)巢样方的植被物种数和植被盖度远高于对照样方;3)影响白尾地鸦巢址选择的主要因素为植被物种数及干扰,其中干扰主要指距道路以及距居民点的距离。综上所述,白尾地鸦的巢址选择受食物等生存需求和躲避干扰等安全因素的双重影响,是生存与繁殖权衡的结果。

Nest-site selection plays an important role in avian breeding success. The Xinjiang Ground-Jays（Podoces biddulphi） is endemic to China and distributed restricted to sandy desert, scrub and desert poplar in the Taklamakan Desert in Xinjiang, China. In this study, the nest-site selection of the Xinjiang Ground-Jays was investigated from April to May, 2017. Quadrat method was used with following parameters being investigated： distance to water, distance to path, distance to settlement, distance to graze land, vegetation species number, vegetation density and vegetation cover. A total of 12 nests were found, of which 9 were built in the bush of the Tamarisk（Tamarix） and located at the edge of desert, and one was built on the ground near the road（Fig. 1, Table 1）. All the 7 parameters were measured for both the nest sites and control plots. Mann-Whitney U test was used to compare the difference between nest sites and control plots, and principal component analysis（PCA） was employed to analyze the main factors of the nest site selection of the Xinjiang Ground-Jay. The results showed that： 1） the vegetation species number and vegetation cover were significantly different between nest sites and control plots. The nest site had more vegetation species number and higher vegetation cover（Table 2）; 2） vegetation species number, the distance of nest to the nearest road and the distance to water played the key roles in nest-site selection of the Xinjiang Ground-Jay（Table 3, Table 4）. In summary, the nest-sites selection of the Xinjiang Ground-Jay was influenced by both the food availability and avoiding the disturbance, as a result of trade-off between survival and reproduction.