Brood parasitism risk drives birds to breed near humans

Although humans have generally negative effects on wildlife, some animals live in close proximity to human residences. Why some animals choose to settle near humans remains a long-standing puzzle. Settling near humans or in urban environments may be beneficial, because of the availability of resources such as food (e.g. supplemental feeding) or suitable nest sites (e.g. cavities), or because of reduced predation risk if predators avoid settlements. Here, we report on a study of Daurian redstarts Phoenicurus auroreus, a common host of the common cuckoo Cuculus canorus, to show that settling near humans can also be a strategy employed by hosts to avoid brood parasitism. First, redstarts suffered an increased risk of brood parasitism with increasing distance from the nearest building. Second, redstarts adjusted their nesting location in response to a seasonally predictable change in the risk of brood parasitism. Third, experimentally simulating the presence of cuckoos during a period when ..., ,

尽管人类活动通常会对野生生物造成负面影响，但仍有部分动物会栖息于距离人类居所极近的区域。为何部分动物会选择在人类活动区域定居，长期以来都是学界待解的经典谜题。在人类居所附近或城市环境中定居往往具备潜在益处：既可以获取充足的食物资源（如人工补充投喂的食物）、适宜的筑巢位点（如树洞等），也可因天敌避开人类聚居区而降低被捕食的风险。本研究以大杜鹃（common cuckoo，学名Cuculus canorus）的常见宿主——北红尾鸲（Daurian redstart，学名Phoenicurus auroreus）为研究对象，证实了在人类居所附近定居同样是宿主规避巢寄生（brood parasitism）的一种生存策略。其一，北红尾鸲遭遇巢寄生的风险会随着与最近人类建筑的距离增加而显著升高；其二，北红尾鸲会根据巢寄生风险的季节性可预测变化调整自身的筑巢位置；其三，本研究在……期间通过实验模拟大杜鹃的存在，