Sea ducks exhibit complex movement patterns throughout their annual cycle; most species use distinct molting and staging sites during migration and disjunct breeding and wintering sites. Although research on black scoters (Melanitta americana) has investigated movements and habitat selection during winter, little is known about their annual-cycle movements. We used satellite telemetry to identify individual variation in migratory routes and breeding areas for black scoters wintering along the Atlantic Coast, to assess migratory connectivity among wintering, staging, breeding, and molt sites, and to examine effects of breeding site attendance on movement patterns and phenology. Black scoters occupied wintering areas from Canadian Maritime provinces to the southeastern United States. Males used an average of 2.5 distinct winter areas compared to 1.1 areas for females, and within-winter movements averaged 1,256 km/individual. Individuals used an average of 2.1 staging sites during the 45-day pre-breeding migration period, and almost all were detected in the Gulf of St. Lawrence. Males spent less time at breeding sites and departed them earlier than females. During post-breeding migration, females took approximately 25 fewer days than males to migrate from breeding sites to molt and staging sites, and then wintering areas. Most individuals used molt sites in James and Hudson bays before migrating directly to coastal wintering sites, which took approximately 11 days and covered 1,524 km. Males tended to arrive at wintering areas 10 days earlier than females. Individuals wintering near one another did not breed closer together than expected by chance, suggesting weak spatial structuring of the Atlantic population. Females exhibited greater fidelity (4.5 km) to previously used breeding sites compared to males (60 km). A substantial number of birds bred west of Hudson Bay in the Barrenlands, suggesting this area is used more widely than believed previously. Hudson and James bays provided key habitat for black scoters that winter along the Atlantic Coast, with most individuals residing for >30% of their annual cycle in these bays. Relative to other species of sea duck along the Atlantic Coast, the Atlantic population of black scoter is more dispersed and mobile during winter but is more concentrated during migration. These results could have implications for future survey efforts designed to assess population trends of black scoters. © 2021 The Wildlife Society.

中文翻译：

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北美东部黑人的年周期运动和物候

海鸭在整个年度周期中表现出复杂的运动模式；大多数物种在迁徙过程中使用不同的蜕皮和分期地点，以及分离的繁殖和越冬地点。尽管对黑人的研究（Melanitta americana) 调查了冬季的运动和栖息地选择，但对其年度周期运动知之甚少。我们使用卫星遥测来确定沿大西洋海岸越冬的黑鲭的迁徙路线和繁殖区的个体差异，评估越冬、分期、繁殖和蜕皮地点之间的迁徙连通性，并检查繁殖地点出勤对运动模式和物候学。黑色苏格兰人占领了从加拿大沿海省份到美国东南部的越冬地区。男性平均使用 2.5 个不同的冬季区域，而女性则为 1.1 个区域，冬季内平均每人移动 1,256 公里。在 45 天的繁殖前迁移期间，个体平均使用了 2.1 个中转站，几乎所有的都在圣劳伦斯湾被发现。雄性在繁殖地的时间更少，而且比雌性更早离开。在繁殖后的迁徙过程中，雌性从繁殖地迁移到蜕皮和集结地，然后是越冬地的时间比雄性少大约 25 天。大多数人在直接迁移到沿海越冬地点之前使用詹姆斯湾和哈德逊湾的蜕皮地点，这需要大约 11 天，覆盖 1,524 公里。雄性往往比雌性提前 10 天到达越冬地区。彼此靠近越冬的个体并没有比偶然预期的更接近，这表明大西洋种群的空间结构较弱。与雄性（60 公里）相比，雌性对先前使用的繁殖地点表现出更高的保真度（4.5 公里）。大量鸟类在贫瘠之地的哈德逊湾以西繁殖，表明该领域的使用比以前认为的更广泛。哈德逊湾和詹姆斯湾为大西洋沿岸冬季的黑人提供了重要的栖息地，大多数人在这些海湾居住了超过 30% 的年度周期。相对于大西洋沿岸的其他海鸭种类，大西洋黑鸭种群在冬季更加分散和流动，但在迁徙期间更加集中。这些结果可能会对未来旨在评估黑人人口趋势的调查工作产生影响。© 2021 野生动物协会。Black scoter 的大西洋种群在冬季更加分散和流动，但在迁移期间更加集中。这些结果可能会对未来旨在评估黑人人口趋势的调查工作产生影响。© 2021 野生动物协会。Black scoter 的大西洋种群在冬季更加分散和流动，但在迁移期间更加集中。这些结果可能会对未来旨在评估黑人人口趋势的调查工作产生影响。© 2021 野生动物协会。