Yellow warblers (Setophaga petechia) use referential ‘seet’ calls to warn mates of brood parasitic brown-headed cowbirds (Molothrus ater). In response to seet calls during the day, female warblers swiftly move to sit tightly on their nests, which may prevent parasitism by physically blocking female cowbirds from inspecting and laying in the nest. However, cowbirds lay their eggs just prior to sunrise, not during daytime. We experimentally tested whether female warblers, warned by seet calls on one day, extend their anti-parasitic responses into the future by engaging in vigilance at sunrise on the next day, when parasitism may occur. As predicted, daytime seet call playbacks caused female warblers to leave their nests less often on the following morning, relative to playbacks of both their generic anti-predator calls and silent controls. Thus, referential calls do not only convey the identity or the type of threat at present but also elicit vigilance in the future to provide protection from threats during periods of heightened vulnerability.

黄莺 ( Setophaga petechia ) 使用参考性的“seet”呼叫来警告同伴寄生的棕头牛鸟 ( Molothrus ater）。为了响应白天的西特叫声，雌莺迅速移动以紧紧地坐在它们的巢穴上，这可以通过物理阻止雌性牛鸟检查和产卵来防止寄生。然而，牛鸟在日出之前产卵，而不是在白天。我们通过实验测试了雌莺是否会在一天被 seet 呼叫警告，通过在第二天可能发生寄生时在日出时保持警惕，将它们的抗寄生虫反应延伸到未来。正如预测的那样，相对于它们的通用反捕食者呼叫和静音控制的回放，白天的 seet 呼叫回放导致雌莺在第二天早上离开巢穴的频率降低。因此，