Experimental manipulation of photoperiod influences migration timing in a wild, long-distance migratory songbird

Previous laboratory studies have demonstrated the role of photoperiod in cueing the migration timing of small land birds; however, how migration timing of young birds in wild environments develops in relation to these cues have rarely been investigated. Such investigations can make important contributions to our developing understanding of the phenotypic plasticity of migration timing to new conditions with climate change, where changes in the timing of nesting may expose juvenile birds to different photoperiods. We investigated the impact of manipulating photoperiod during nestling development in a long-distance migratory songbird on the timing of post-breeding movements in the wild. Using programmable lighting installed in the nest-boxes of purple martins (Progne subis), we exposed developing nestlings, from hatch to fledge date, to an extended photoperiod that matched the day length of the summer solstice in Manitoba, Canada. We found that birds with a simulated, earlier photoperiod ...

既往实验室研究已证实，光周期（photoperiod）可作为信号调控小型陆地鸟类的迁徙时间；然而，野外环境中幼鸟的迁徙时间如何随这类信号调控其发育进程，目前仍鲜有相关研究。此类研究可助力我们进一步理解气候变化背景下，迁徙时间对新环境的表型可塑性（phenotypic plasticity）——筑巢时间的改变可能会使幼鸟暴露于不同的光周期环境中。本研究以一种长距离迁徙鸣禽为对象，探究了雏鸟发育阶段（从破壳至离巢日）的光周期调控，对其野外繁殖后活动时间的影响。我们通过安装在北美紫燕（Progne subis）巢箱内的可编程照明装置，将孵化至离巢阶段的发育雏鸟暴露于模拟的延长光周期中，该光周期与加拿大曼尼托巴省的夏至日长一致。本研究发现，接受模拟提前光周期处理的鸟类……