Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, United States of America.
Department of Biology, Willamette University, Salem, OR, United States of America.
PLoS One. 2018 Nov 8;13(11):e0206258. doi: 10.1371/journal.pone.0206258. eCollection 2018.
The availability of small, lightweight tracking devices enhances our ability to study birds during mobile phases of their lives. Tree Swallows Tachycineta bicolor, a model species of wild songbird, are well-studied during their breeding season; but our understanding of their biology at other times of the year, when they are not tied to the fixed location of a nest, is more limited. We developed a lightweight radio tag with no battery (solar nanotag) to study the movements of small animals, and we deployed it to explore the behavior of Tree Swallows after the end of their summer breeding season. We tagged 32 breeding adult swallows and 36 juveniles and monitored their presence and absence at the breeding site during the post-fledging period. Although our observations are based on very small sample sizes, the tags revealed previously unknown patterns in Tree Swallow behavior during the post-breeding season. Some Tree Swallow fledglings continued to visit the site repeatedly in the months following the nesting season, with the latest detection occurring on September 30th; by contrast, all adults had permanently departed by the end of July. These results inform future hypotheses about post-breeding movements in Tree Swallows. But, more generally, the detection of tagged swallows on their distant wintering grounds, seven months after tagging, indicates the potential of studying small passerine movements throughout their entire lifetimes, and suggests a rich array of applications for these "Life Tags" to study the movements of small animals world-wide.
小型、轻便的追踪设备的可用性提高了我们在鸟类生命的移动阶段研究它们的能力。树燕 Tachycineta bicolor 是野生鸣禽的典型物种，在繁殖季节得到了很好的研究；但我们对它们在一年中其他时间的生物学理解，即当它们不局限于巢的固定位置时，更为有限。我们开发了一种没有电池的轻便无线电标签（太阳能纳米标签）来研究小动物的运动，并将其用于探索夏季繁殖季节结束后树燕的行为。我们给 32 只繁殖的成年燕子和 36 只幼鸟贴上标签，并在离巢后的时期监测它们在繁殖地的存在和缺失情况。尽管我们的观察基于非常小的样本量，但这些标签揭示了树燕在繁殖后季节的行为中以前未知的模式。一些树燕幼鸟在巢季后的几个月里继续反复访问该地点，最晚的一次检测发生在 9 月 30 日；相比之下，所有成年鸟都在 7 月底永久离开。这些结果为未来关于树燕繁殖后迁徙的假设提供了信息。但是，更普遍地说，在标记后的七个月里，在遥远的越冬地检测到标记的燕子，表明有可能在整个生命周期内研究小型雀形目动物的运动，并为这些“生命标签”提供了丰富的应用，以研究世界各地小型动物的运动。
