Timber harvest and tree size near nests explains variation in nest site occupancy but not productivity in northern goshawks (Accipiter gentilis)

Conservation concern for the northern goshawk (Accipiter gentilis) reflects evidence that goshawks may abandon nest sites or suffer from reduced nesting success in response to some forms of timber harvest. However, this evidence is mixed and has yet to be reviewed systemically and quantitatively. Therefore, we conducted a meta-analysis to assess the extent to which timber harvest and tree size explain variation in goshawk productivity and site occupancy. Goshawk productivity was not significantly explained by the presence of nearby timber harvest nor by the average size of nearby trees either in North America or in Eurasia or when averaged across all studies. Effect sizes differed dramatically among studies and the average effect size was close to zero (Zr = 0.04). However, timber harvest and tree size together more strongly explained goshawk occupancy of nest sites or territories. Within studies, goshawk nest sites or territories with less timber harvest nearby or relatively larger tre...

北苍鹰（Accipiter gentilis）的保护关切，源于有证据表明其在应对部分类型的木材采伐时，可能出现弃巢行为，或遭遇繁殖成功率下降的问题。然而此类证据存在分歧，且尚未经过系统性、定量化的综述研究。为此，我们开展了一项元分析，以评估木材采伐与林木大小对苍鹰繁殖生产力及巢址占用情况变异的解释程度。无论是在北美还是欧亚大陆，亦或是综合所有研究的平均结果来看，周边区域的木材采伐存在与否，以及周边林木的平均大小，均未对苍鹰的繁殖生产力产生显著影响。不同研究间的效应量差异显著，平均效应量接近零（Zr = 0.04）。不过，木材采伐与林木大小二者结合，对苍鹰巢址或领域的占用情况具有更强的解释力。在单项研究内部，周边木材采伐程度更低或林木相对更大的苍鹰巢址或领域……