Etchart Léa, Lecomte Nicolas, Dechaume-Moncharmont François-Xavier, Moreau Jérôme, Lang Johannes, Pagnon Thomas, Sittler Benoit, Teixeira Maria, Bollache Loïc, Gilg Olivier
CNRS, Chrono-Environnement (UMR 6249), Université Marie et Louis Pasteur, 25000, Besançon, France.
Canada Research Chair in Polar and Boreal Ecology and Centre d'Études Nordiques, Université de Moncton, Moncton, NB, Canada.
Oecologia. 2025 May 28;207(6):92. doi: 10.1007/s00442-025-05735-y.
Parents can abandon their current clutch when reaching a physiological threshold to prioritise their survival and future breeding in the trade-off against current reproduction. Incubation is metabolically costly, and regular recesses are necessary to replenish energy reserves. Thus, an increase in the duration of these foraging trips may signal diminishing reserves and perhaps impending abandonment. Here, we tested the hypothesis that the probability of abandonment of uniparental nest is directly linked to the duration of extended recesses (i.e., recesses > 120 min). Analysing 13 years of breeding behaviour from Sanderlings (Calidris alba) using thermologgers placed in 120 nests, we found that both the frequency and duration of extended recesses were higher in nests that were ultimately abandoned. The probability of nest abandonment increased with time spent in extended recesses during incubation, with the final day before abandonment proving critical in the decision-making. In contrast, short recesses showed no relationship with abandonment probability, and neither recess type changed significantly as nests approached hatching, confirming the specificity of extended recesses as indicators of abandonment. With such results, parents likely remain at the nest until their reserves fall below a physiological threshold, when they have no choice but to leave the nest when the costs-benefits balance becomes unsustainable for the parent. Our study suggests the key link between extended recesses and nest abandonment; it paves the way for quantifying foraging success and variations in energy reserves of individuals to provide deeper insights into the mechanisms driving reproductive decisions and their impact on population dynamics.
当达到生理阈值时，为了在当前繁殖与生存及未来繁殖之间进行权衡以优先考虑自身生存和未来繁殖，亲鸟可能会放弃当前的一窝蛋。孵卵代谢成本高昂，定期休息对于补充能量储备是必要的。因此，这些觅食行程时长的增加可能预示着能量储备减少，或许即将放弃。在此，我们检验了这样一个假设：单亲巢穴被放弃的概率与延长休息时间（即休息时间超过120分钟）直接相关。通过分析使用放置在120个巢穴中的温度记录器所获取的13年的三趾滨鹬（Calidris alba）繁殖行为数据，我们发现最终被放弃的巢穴中延长休息的频率和时长都更高。孵卵期间在延长休息中所花费的时间增加了巢穴被放弃的概率，在放弃前的最后一天在决策过程中被证明至关重要。相比之下，短时间休息与放弃概率无关，而且随着巢穴接近孵化，两种休息类型都没有显著变化，这证实了延长休息作为放弃指标的特异性。基于这样的结果，亲鸟可能会一直留在巢穴直到其储备低于生理阈值，此时当成本效益平衡对亲鸟来说变得不可持续时，它们别无选择只能离开巢穴。我们的研究揭示了延长休息与巢穴放弃之间的关键联系；它为量化个体的觅食成功率和能量储备变化铺平了道路，以便更深入地了解驱动繁殖决策的机制及其对种群动态的影响。
