Lack of avian predators is associated with behavioural plasticity in nest construction and height in an island songbird

Orange-crowned warblers, Leiothlypis celata sordida, breeding on the California Channel Islands exhibit remarkable variation in their nest structure and placement, providing an intriguing exception to the general pattern that avian nest structure and nest site selection are highly conserved characters. We examined nest construction at both the population and individual scale to test whether warblers on Santa Catalina Island change their nest construction in response to nest height. At the population level, warblers built both lighter, grass-dominated ground nests and heavier off-ground nests that contained more ridged materials and less grass. The probability of nest success was significantly and positively correlated with nest height. At the individual level, we found the same individuals were capable of building on- and off-ground nests between nesting attempts within the same season. However, nest construction was highly variable among individuals and not significantly correlated wit...

在加利福尼亚海峡群岛繁殖的橙顶林莺（Orange-crowned warblers，学名Leiothlypis celata sordida），其巢的结构与放置位置存在显著变异，这为鸟类巢结构和巢址选择是高度保守性状这一普遍模式提供了一个引人入胜的例外。我们从种群和个体两个尺度考察了巢的构建，以验证圣卡塔利娜岛上的林莺是否会根据巢高改变其筑巢方式。在种群层面，林莺既会建造较轻、以草为主的地面巢，也会建造较重的离地巢——后者包含更多带棱纹的材料且草含量更少。巢成功的概率与巢高呈显著正相关。在个体层面，我们发现同一林莺个体在同一繁殖季的不同筑巢尝试中，既能建造地面巢也能建造离地巢。然而，巢的构建在个体间存在高度变异，且与……无显著相关性。