摘要
Aims To test the prediction that the occurrence in space and time of fæders on ecological grounds should track that of females.
Methods The fraction of fæders was estimated in five morphometric data sets that were collected over four decades in four different countries in three different seasons (comprising 9133 Ruffs). The regression of fæder–female fractions was tested against the null model assuming that the number of fæders is 1.0% of females.
Results The fraction of fæders in catches averaged 1.03%, varying between 0.3% in autumn in the UK up to 0.85% in Sénégal in winter and 1.04% in The Netherlands in spring. On a stopover in The Netherlands the fraction decreased from 1.3% to 0.7% when the females started to arrive. At all four spatial and temporal scales the regression of fæder–female fractions deviated from the null model: we found high fractions of fæders in catches with low fractions of females, indicating that fæders rather associate with the larger-sized ‘normal’ males.
Conclusion We suggest that fæders spend the winter, and migrate with, the larger-sized lekking males, and we propose that any survival costs associated with the use of suboptimal habitats is compensated by higher reproductive success as sneakers on leks.
摘要译文
目的测试生态理论上的空间和时间的发生跟踪女性的预测。方法在三个不同季节（包括9133 Ruffs）的四个不同国家收集了四十年的五个形态测量数据集中估计的分数。假设女性的数量为女性的1.0％，则针对空模型测试女性部分的回归。结果捕获量的平均值分别为1.03％英国秋季在秋季为0.3％，冬季为Sénégal，为0.85％，春季为荷兰1.04％。在荷兰的中途停留，分数从1.3％下降到0。7％的女性开始到达。在所有四个空间和时间尺度上，女 - 女分数的回归偏离空模型：我们发现高分数的女性在低分数的捕获中，表明与更大规模的“正常”男性相关联。结论我们建议，老年人过冬，迁入大型的老年男性，我们建议与使用次最佳栖息地相关的任何生存成本都可以通过较高的生殖成功获得补偿，作为运动鞋。
Yvonne I. Verkuil; Joop Jukema; Jennifer A. Gill; Natalia Karlionova; Johannes Melter; Jos C.E.W. Hooijmeijer ; Theunis Piersma. Non-breeding fæder Ruffs Philomachus pugnax associate according to sex, not morphology: Capsule Fæders (males that are female look-alikes) associate with males rather than females, at several different spatial scales.[J]. Bird Study, 2008,55(3): 241-246