Individual optimization of reproduction in a long-lived migratory bird: a test of the condition-dependent model of laying date and clutch size
Individual optimization of reproduction in a long-lived migratory bird: a test of the condition-dependent model of laying date and clutch size
复制标题
DOI：
10.1111/j.1365-2435.2010.01824.x
复制
发表时间：
2011-06-01
影响因子：
5.2
通讯作者：
Gilchrist, H. Grant
中科院分区：
文献类型：
--
作者：
Descamps, Sebastien;Bety, Joel;Gilchrist, H. Grant
P>1。最优理论预测，到达繁殖区的时间和到达状态将决定迁徙生物的繁殖时间和投资。我们通过描述性数据、路径分析和实验操作，使用条件依赖性个体优化模型（Ardea68, 1980, 225 和 The American Naturalist143, 1994, 698）在普通绒鸭中测试了这一想法。2．我们的结果支持从优化模型得出的因果路径，表明个体根据到达日期和到达时的身体状况调整其生殖决策。3。与身体状况无关，早到的雌鸟有更长的预产期，但仍然比晚到的鸟更早开始筑巢，产下的窝也更大。与到达日期无关，状况良好的雌性比状况差的雌性产蛋早。对产蛋前雌性身体状况的处理证实了状况与产蛋日期之间存在因果关系。4．雌性绒鸭似乎会根据其外部（即影响卵价值的环境条件）和内部（即身体状况）状态来优化繁殖决策。这些调整似乎最大限度地降低了繁殖的适应成本，其中较高的窝数与明显较低的存活率或未来繁殖概率无关。5。我们的研究强调了以下几点的重要性：（i）同时考虑迁徙时间、个体状态和蛋值的季节性变化，以清楚地了解鸟类的繁殖决策；（ii）认识到解释为什么某些个体延迟繁殖和/或产下小窝的潜在直接和最终因素。
P>1. Optimality theory predicts that both timing of arrival and arrival state on the breeding area will determine reproductive timing and investment in migratory organisms. We tested this idea using a condition-dependent individual optimization model (Ardea68, 1980, 225 and The American Naturalist143, 1994, 698) in common eider ducks through descriptive data, path analyses and experimental manipulation.2. Our results support the causal pathways drawn from the optimization model indicating that individuals adjust their reproductive decisions as a function of their arrival date and body condition at arrival.3. Independent of body condition, early-arriving females had a longer pre-laying period, but still initiated their nests earlier, and produced larger clutches than late-arriving birds. Independent of arrival date, females in good condition laid earlier than those in poor condition. Manipulation of pre-laying female body condition confirmed that the relationship between condition and laying date was causal.4. Female common eiders appear to optimize reproductive decisions in response to both their external (i.e. environmental conditions affecting the egg-value) and internal (i.e. body condition) states. These adjustments seem to minimize the fitness costs of reproduction, in which higher clutch size is not associated with an apparent lower survival or future breeding probability.5. Our study emphasizes the importance of (i) simultaneously considering the timing of migration, the state of individuals and the seasonal change in egg-value to understand clearly birds' breeding decisions and (ii) appreciating the potential proximate and ultimate factors explaining why some individuals delay breeding and/or produce small clutches.