For most animals, the rearing environment is an important factor influencing early offspring development and behaviour. Also, in altricial birds, where the rearing environment (nest) is usually restricted, it is known that if sufficient nest space is provided, offspring show social interactions and a variety of other behaviours. In fact, the available nest space has been identified as an important determinant for the occurrence or outcome of social interactions. In this context, we predict different behaviours like food acquisition, intra-brood competition, comfort behaviour or defecation activities also happen at specific sites within the nest and allow differential nest-space use. We further predict, that even offspring within a brood may differently experience their rearing environment. In line with this, e.g. nestling age, brood size or parental food allocation rules could be influential factors. In this study, we therefore investigated offspring nest-space use in altricial hoopoe nestlings (Upupa epops) raised in spacious nest boxes. In particular, we focused on nest-space use in relation to four major offspring behaviours, namely successful food acquisition, aggressive interactions, comfort and resting behaviour and defecation, additionally including parental feeding strategy (feeding from inside or outside the nest box), nestling age and brood size as potentially influential factors. Our results reveal that nestlings do not use the nest space equally but use specific locations for different purposes. Our results further suggest that beside behaviour also offspring age, brood size and parental feeding strategy influence their nest-space use. In conclusion, differential nest-space use can occur even in nestlings and already at an early age. Thus, nest space seems to be an important nest quality feature determining not only nest-space use but also affects offspring social interactions.

对于大多数动物而言，饲养环境是影响后代早期发育和行为的重要因素。同样，在通常限制饲养环境（巢）的al鸟中，已知如果提供了足够的巢隙，后代会表现出社交互动和多种其他行为。实际上，可用的巢空间已被确定为社交互动发生或结果的重要决定因素。在这种情况下，我们预测在巢内的特定位置也会发生不同的行为，例如食物获取，种内竞争，舒适行为或排便行为，并允许不同的巢空间使用。我们进一步预测，即使是育雏中的后代也会经历不同的饲养环境。与此相符，例如雏鸟时代，育雏规模或父母的食物分配规则可能是影响因素。因此，在这项研究中，我们调查了在戴胜戴胜小鸟雏鸟（Upupa epops）放在宽敞的巢箱中。特别是，我们专注于与四个主要后代行为相关的巢空间使用，即成功获取食物，积极的互动，舒适和休息行为以及排便，此外还包括父母的喂养策略（从巢箱内部或外部喂养），雏鸟年龄和繁殖体大小是潜在的影响因素。我们的结果表明，雏鸟不会平等地使用巢空间，而是将特定位置用于不同目的。我们的结果进一步表明，除了行为方式外，后代的年龄，育雏量和父母的喂养策略也会影响其巢空间的利用。总之，即使在雏鸟中，也早在幼年时，巢空间的差异化使用就可能发生。从而，