Zhang Yuhan, Zhong Guo, Wang Longwu, Liang Wei
Ministry of Education Key Laboratory for Ecology of Tropical Islands, College of Life Sciences, Hainan Normal University, Haikou, 571158, China.
School of Life Sciences, Guizhou Normal University, Guiyang, 550001, China.
Anim Cogn. 2024 Dec 12;27(1):83. doi: 10.1007/s10071-024-01919-w.
Egg retrieval in birds may help ensure the survival of eggs and improve reproductive success. However, with the risk of brood parasitism, for ground-nesting or cavity-nesting bird hosts, there is a significant reproductive cost and thus a reduction in fitness if the host wrongly retrieved the parasitic eggs. The south rock bunting (Emberiza yunnanensis) and yellow-throated bunting (E. elegans) are hosts for common cuckoos (Cuculus canorus), which coexist within the study area and breed sympatrically in ground nests. Previous studies have found that these two species exhibit strong egg recognition and egg rejection of non-mimetic eggs. In this study, red model eggs, budgerigar eggs, and the host's own eggs were used to assess the recognition and retrieval behavior of two bunting hosts, particularly in response to different types of eggs placed at the nest edge. The results showed that both bunting hosts retrieved ca. 80% of own eggs and did not retrieve any red model eggs. This indicated that both species could distinguish non-mimetic model eggs from their own eggs and make appropriate decisions, which is consistent with their responses when encountering foreign eggs in the nest. However, both species simultaneously retrieved some (8.3% for the yellow-throated bunting and 19% for south rock bunting) of the highly mimetic budgerigar eggs, indicating that the degree of mimicry of foreign eggs affects their egg recognition and egg retrieval behavior. Factors such as parasitism risk, nest predation pressure, age differences, and experience of parent birds may combine to influence egg retrieval behavior of the host.
鸟类的取卵行为可能有助于确保卵的存活并提高繁殖成功率。然而，由于存在巢寄生风险，对于地面筑巢或洞穴筑巢的鸟类宿主来说，如果宿主错误地取回寄生卵，就会有显著的繁殖成本，进而导致适合度降低。赭红尾鸲（Emberiza yunnanensis）和黄喉鹀（E. elegans）是大杜鹃（Cuculus canorus）的宿主，它们在研究区域内共存，并在地面巢穴中同域繁殖。先前的研究发现，这两个物种对非拟态卵表现出强烈的卵识别和弃卵行为。在本研究中，使用红色模型卵、虎皮鹦鹉卵和宿主自身的卵来评估两种鹀宿主的识别和取卵行为，特别是对放置在巢边缘的不同类型卵的反应。结果表明，两种鹀宿主都取回了约80%的自身卵，且未取回任何红色模型卵。这表明这两个物种都能将非拟态模型卵与自身卵区分开来并做出适当决策，这与它们在巢中遇到外来卵时的反应一致。然而，两种鹀同时取回了一些（黄喉鹀为8.3%，赭红尾鸲为19%）高度拟态的虎皮鹦鹉卵，这表明外来卵的拟态程度会影响它们的卵识别和取卵行为。寄生风险、巢捕食压力、年龄差异和亲鸟经验等因素可能共同影响宿主的取卵行为。
