Identifying risks to populations of migratory shorebirds

我的研究项目的目的是了解单个滨鸟在繁殖、迁徙和越冬期间的栖息地选择模式的变化程度，并确定是否存在对栖息地偏好的持续选择。总体目标是了解栖息地线索是否具有灵活性，从而使滨鸟能够在每年周期的每个季节（繁殖、迁徙和越冬）对栖息地的变化做出反应。与适应性的联系是决定是否存在持续选择的关键。这些目标只能通过单独标记的鸟类来实现，在研究计划的持续时间内，我们有足够的数量在滨鸟年周期的所有阶段进行分析。在Churchill， MB地区有三种最常见的繁殖滨鸟（Charadrius semipalmatus， Calidris alpina和Numenius phaeopus）的种群，我的HQP有过经验。我的HQP也有关于繁殖地点和相关繁殖成功率的历史数据。在繁殖过程中，我预测个体栖息地偏好的可重复性较低，因为应该强烈选择繁殖地点，以促进成年繁殖者的生存和繁殖成功。我预测，由于灌木和乔木的入侵，高山毛茛和褐皮毛茛会有强烈的持续选择。在迁徙期间，在詹姆斯湾西部的三个地点（Longridge， Little Piskwamish和North Point），我建议使用HQP观察单个彩色条纹的鸟类，以及检测配备纳米标签的鸟类，以记录位置和相关的地貌特征和食物资源。这三个地点的生境特点差别很大。我们预测，由于对特定中转站的熟悉度带来的适应度优势，特定中转站的选择在多年间具有一致性。无法预测在较短时间内迁移到一个地点内特定栖息地的一致性，因为在迁移过程中，个体应该有很强的选择，以追踪短暂和不完整的食物资源，并避免危险。在迁徙过程中，质量增加、中途停留长度和离开时间将被用作适应度的代理。最后，在8-9个月的非繁殖季节，HQP将研究两个南温带地区（美国东南部）捕食风险不同的觅食和栖息地点之间的个体运动模式。我们预测，在捕食者存在的情况下，栖息地和觅食地点在季节内和季节之间的移动会更高。在非繁殖期间，身体状况和表观存活率将作为适应度的估计。

The objective of my research program is to understand the degree of variability in an individual shorebird’s habitat selection patterns during breeding, migration and overwinter and to determine whether there is ongoing selection for habitat preferences. The overarching goal is to understand whether there is flexibility in habitat cues that will provide the ability for shorebirds to respond to changing habitats during each season (breeding, migration and overwintering) of the annual cycle. Links with fitness are critical for determining whether there is ongoing selection. These objectives can only be met using individually marked birds, of which we have sufficient numbers for analysis during all stages of the shorebird annual cycle, over the duration of the research program. In the Churchill, MB region marked populations of the three most commonly breeding shorebirds (Charadrius semipalmatus, Calidris alpina and Numenius phaeopus) exist, species for which my HQP have experience. My HQP also have historical data on breeding locations and associated reproductive success. During breeding I predict low repeatability of individual habitat preferences because breeding sites should be strongly selected to promote both survival of the adult breeder and reproductive success. For C. alpina and N. phaeopus I predict strong ongoing selection as a function of shrub and tree encroachment. During migration, in three locations along western James Bay, ON (Longridge, Little Piskwamish and North Point), with HQP I propose to use sightings of individually colour-banded birds as well as detections of those outfitted with nanotags, to document locations and associated geomorphological features and food resources. The three locations vary considerably in habitat features. We predict consistency in the choice of particular migratory stopover locations across years because of fitness advantages associated with familiarity of particular stopover sites. Consistency in movements over shorter time periods and to particular habitats within a location is not predicted because during migration there should be strong selection for individuals to track ephemeral and patchy food resources, and to avoid danger. During migration, mass gain, stopover lengths and departure times will be used as proxies of fitness. Finally, during the 8-9 mo non-breeding season HQP will study individual patterns of movements between foraging and roosting sites at two south temperate locations (in southeastern US) that vary in predation risk. We predict higher within and between season movements of both roost and foraging sites in the presence of predators. During non-breeding body condition and apparent survival will be used as estimates of fitness.