Hamer KC, Lynnes AS, Hill JK
Department of Biological Sciences, University of Durham
Anim Behav. 1999 Mar;57(3):627-631. doi: 10.1006/anbe.1998.0994.
Procellariiform seabirds such as the Manx shearwater Puffinus puffinus, rear only one chick at a time but may breed many times in their lives; parents should thus limit food delivery to the chick in keeping with the balance between current and future reproductive output. Yet procellariiform chicks accumulate large quantities of lipid, which may provide a buffer against pronounced and unpredictable variation in food provisioning, resulting in part from an inability of parents to regulate food supply to the nest. We switched chicks between nests to examine the roles of parents and offspring in controlling food delivery. The serial autocorrelation in age-specific body masses for unmanipulated chicks decreased from 0.61 (P< 0.01) to 0.35 (NS) over a period of 15 days and remained nonsignificant thereafter. By contrast, the serial autocorrelation for switched chicks increased from 0.64 (P< 0.01) to 0.83 (P< 0.001) and the serial cross-correlation rose from 0.23 (NS) to 0.50 (P< 0.05). These results supported both chick determination and parental determination models of food provisioning, indicating that chicks conveyed information about their nutritional status, which parents acted upon by adjusting their rate of food delivery. We discuss these results in relation to the optimization of nestling lipid reserves and parental foraging effort. We suggest that information conveyed by the chick's begging intensity serves to reduce the provisioning rate to well-fed chicks, but parents cannot or do not increase food provisioning to poorly fed chicks. Such adjustment of food provisioning does not refute the hypothesis that nestling obesity provides a buffer against highly variable food delivery. Copyright 1999 The Association for the Study of Animal Behaviour.
诸如马恩岛剪水鹱（Puffinus puffinus）这样的鹱形目海鸟每次只养育一只雏鸟，但它们一生中可能繁殖多次；因此，亲鸟应该根据当前和未来繁殖产出之间的平衡来限制对雏鸟的食物供应。然而，鹱形目雏鸟会积累大量脂肪，这可能为应对食物供应明显且不可预测的变化提供缓冲，部分原因是亲鸟无法调节巢穴中的食物供应。我们将雏鸟在巢穴间进行交换，以研究亲鸟和雏鸟在控制食物供应方面的作用。在15天的时间里，未被操纵的雏鸟特定年龄体重的序列自相关性从0.61（P<0.01）降至0.35（无显著性差异），此后一直不显著。相比之下，交换雏鸟后的序列自相关性从0.64（P<0.01）增至0.83（P<0.001），序列互相关性从0.23（无显著性差异）升至0.50（P<0.05）。这些结果支持了食物供应的雏鸟决定模型和亲鸟决定模型，表明雏鸟传达了它们营养状况的信息，亲鸟据此调整食物供应速率。我们结合雏鸟脂肪储备的优化和亲鸟觅食努力来讨论这些结果。我们认为，雏鸟乞食强度传达的信息有助于降低对营养良好雏鸟的食物供应速率，但亲鸟无法或不会增加对营养不良雏鸟的食物供应。这种食物供应的调整并不反驳雏鸟肥胖为应对高度可变的食物供应提供缓冲的假设。版权所有1999年动物行为研究协会。
