1. For Rapa Nui (Easter Island) and its largest islet, Motu Nui, the change of the species assemblage over time was analysed, and a trait‐based approach to evaluate the potential losses in seabird function across the past centuries was applied. At a finer scale, the seasonal changes in seabird species composition in the current seabird assemblage was assessed to better understand the dynamics of the long‐term inferred patterns.
2. For Rapa Nui, the composition of the seabird assemblage between the prehistorical, historical, and current time has changed significantly. The most critical change, probably associated with human colonization, was observed between prehistoric and current times. The current diminished number of nesting seabird species was probably the result of local extirpation without evidence of colonization by new species.
3. For Motu Nui, changes in species composition were also followed by changes in trait structure, which were smaller than observed in Rapa Nui. This is probably due to the presence of a relatively high number of related species (i.e. Procellariids) with high similarities in their foraging behaviour.
4. The nesting seabird assemblages in Rapa Nui and Motu Nui differ in exposure to risk; thus, conservation strategies applied to the islands should be planned on a fine spatial scale. For Rapa Nui, which is an urban wildlife area with several invasive species and a low number of remaining native seabird species, management should focus on fencing and pets control. For Motu Nui, management should instead focus on the establishment of quarantine and other biosecurity tools to avoid both the entry and proliferation of new invasive species.

中文翻译：

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拉帕努伊（复活节岛）多用途海洋保护区海鸟组合结构的时间变化和性状多样性

1. 对于Rapa Nui（复活节岛）及其最大的小岛Motu Nui，分析了物种组合随时间的变化，并应用了基于特征的方法来评估过去几个世纪海鸟功能的潜在损失。在更精细的规模上，对当前海鸟组合中海鸟物种组成的季节性变化进行了评估，以更好地了解长期推断模式的动态。
2. 对于拉帕努伊（Rapa Nui），史前，历史和当前时间之间的海鸟组合的组成已发生了显着变化。在史前和现代之间观察到了最关键的变化，可能与人类殖民有关。目前减少的筑巢海鸟物种数量可能是当地灭绝的结果，而没有新物种定殖的证据。
3. 对于Motu Nui，物种组成的变化也伴随着性状结构的变化，该变化小于在Rapa Nui中观察到的变化。这可能是由于在觅食行为上具有高度相似性的相对大量的相关物种（即Procellariids）的存在。
4. 拉帕努伊（Rapa Nui）和莫图努伊（Motu Nui）的筑巢海鸟组合面临的风险有所不同。因此，应用于岛屿的保护策略应在精细的空间范围内进行规划。对于拉帕努伊（Rapa Nui），这是一个城市野生动植物区，有几种外来入侵物种，而剩余的本地海鸟物种数量很少，管理应着重于围栏和宠物控制。对于Motu Nui而言，管理层应将重点放在建立检疫和其他生物安全工具上，以避免新入侵物种的进入和扩散。