小杜鹃对强脚树莺的巢寄生及其卵色模拟

Brood parasitism and egg mimicry on Brownish-flanked Bush Warbler (Cettia fortipes) by Lesser Cuckoo (Cuculus poliocephalus)

于1999-2009年的鸟类繁殖季(4-8月)对贵州宽阔水自然保护区内的强脚树莺(Cettia fortipes)的繁殖进行监测,并采用光纤光谱仪,通过主成分分析、反射光谱、罗宾逊投射等方法对强脚树莺的卵色与小杜鹃(Cuculus poliocephalus)对其寄生的卵色模拟程度进行分析。研究结果表明,强脚树莺的繁殖成效在不同年份间均无显著差异,但其巢被捕食率和巢被寄生率都较高,分别为49.26%和9.18%。通过反射光谱分析,表明小杜鹃卵在色调和色度上高度模拟强脚树莺的卵,但其亮度高于宿主卵,而且在人眼无法探测的紫外光部分存在差异。

Nest fate of Brownish-flanked Bush Warbler （Cettia fortipes） was conducted in breeding seasons from 1999 to 2009 in Kuankuoshui Natural Reserve, Guizhou province. Predation rate, parasitism rate, hatching success, nesting success and reproductive success were surveyed and egg color was quantified using spectrophotometer. Principal component analysis, reflectance spectrum and Robinson Project were used to analyze the egg color of bush warbler and egg mimicry of Lesser Cuckoo （Cuculus poliocephalus） in parasitized nests. Our results indicated that the Brownish-flanked Bush Warbler suffered from high predation rate and relatively high parasitism rate of 49.26% and 9.18%, respectively. Reflectance analysis showed that the hue and chroma of Lesser Cuckoo eggs were highly mimetic but the egg brightness and ultraviolet reflectance were different from the bush warbler.