ABSTRACT Capsule: Differences in parental investment between sexes and stage of the breeding period were found in Bonelli’s Eagles Aquila fasciata. Aims: To describe the sexual differences in parental behaviour of Bonelli’s Eagles and to assess the sex-specific pattern of variation in parental investment in relation to the breeding period. Methods: Between 2006 and 2016, we monitored the parental behaviour of 11 pairs of Bonelli’s Eagles during the incubation and chick-rearing periods in southeastern Spain. Observations were made using 20–60× telescopes from points overlooking the territory at a distance of about 500–800 m from the nest. Results: Our results reveal a marked division in parental duties in Bonelli’s Eagles. Females invested more effort in incubation, nest attendance, chick feeding and nest-building, while males contributed more to food provisioning. Nest attendance and feeding by females decreased with time, and both parents adjusted their provisioning effort in relation to nestling age. Most changeovers took place during the middle of the day, when male provisioning rates and temperatures reach their maximum. Conclusion: Intersexual differences are discussed in the context of the prey capture difficulty hypothesis, which proposes that intra-pair prey differences, due to large sexual size dimorphism, should be particularly advantageous among raptors that pursue agile prey.

中文翻译：

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Bonelli's Eagles Aquila fasciata 的繁殖行为和时间活动预算：父母活动中的显着性别差异

摘要胶囊：在 Bonelli 的 Eagles Aquila fasciata 中发现了两性和繁殖期阶段之间亲本投资的差异。目的：描述 Bonelli's Eagles 亲本行为的性别差异，并评估与繁殖期相关的亲本投资变异的性别特异性模式。方法：在 2006 年至 2016 年期间，我们监测了西班牙东南部 11 对 Bonelli's Eagles 在孵化和雏鸡饲养期间的亲本行为。使用 20-60 倍望远镜从距巢穴约 500-800 m 处俯瞰领土的点进行观察。结果：我们的结果揭示了 Bonelli's Eagles 的父母职责存在显着差异。雌性在孵化、筑巢、喂雏和筑巢方面投入更多精力，而男性对食物供应的贡献更大。随着时间的推移，雌鸟的出巢率和喂食量减少，父母双方都根据雏鸟的年龄调整了他们的供应努力。大多数转换发生在中午，当男性供应率和温度达到最大值时。结论：在猎物捕获困难假说的背景下讨论了两性差异，该假说提出，由于大的两性大小二态性，对内猎物的差异在追求敏捷猎物的猛禽中应该特别有利。当男性供应率和温度达到最大值时。结论：在猎物捕获困难假说的背景下讨论了两性差异，该假说提出，由于大的两性大小二态性，对内猎物的差异在追求敏捷猎物的猛禽中应该特别有利。当男性供应率和温度达到最大值时。结论：在猎物捕获困难假说的背景下讨论了两性差异，该假说提出，由于大的两性大小二态性，对内猎物的差异在追求敏捷猎物的猛禽中应该特别有利。