Thompson Hillary L, Caven Andrew J, Schmidt Stephanie M, Sicich Bianca R F, Sarrol Alexis J, Szyszkoski Eva K, Gordon Nicole M
International Crane Foundation Baraboo Wisconsin USA.
Louisiana Department of Wildlife and Fisheries Gueydan Louisiana USA.
Ecol Evol. 2025 Apr 25;15(4):e71284. doi: 10.1002/ece3.71284. eCollection 2025 Apr.
The reintroduced Eastern Migratory Population (EMP) of Whooping Cranes () has exhibited appropriate breeding behavior, including pair formation, territory defense, nest building, and fertile egg production. However, recruitment has been lower than what is needed for a self-sustaining population due to high chick mortality. During 2006-2023, 194 chicks hatched in the EMP, with only 36 surviving to fledging. For the population to succeed without continued releases of captive-reared individuals, we must develop management strategies that increase recruitment to a level above mortality rates. We examined apparent weekly survival data of wild-hatched Whooping Crane chicks collected via aerial and ground surveys using radio telemetry from 2006 to 2023. In this study, we explored relationships between chick survival and a host of potentially impactful predictor variables including parental experience, parental life history, habitat, ecoregion, weather, and climate, as well as nest and clutch characteristics using Cox Proportional Hazard Regression Models. Our results indicate that a chick without a sibling has an increased probability of survival. Survival probability also increased with collective parental experience and warm days (> 32°C) during the first 4 weeks after hatch. Our data indicate that parental experience is a reliable predictor of recruitment. Adult survival may therefore be indirectly linked with low chick survival as experienced adults are too often lost from this population. Additionally, our results suggest that efforts to collect a single egg from two-egg nests may improve weekly survival of Whooping Crane chicks.
重新引入的美洲鹤东部迁徙种群（EMP）已经表现出适当的繁殖行为，包括配对、领地防御、筑巢和产有 fertile 卵。然而，由于雏鸟死亡率高，补充率一直低于自我维持种群所需的水平。在2006年至2023年期间，EMP中有194只雏鸟孵化，只有36只存活到羽翼丰满。为了使种群在不持续释放人工饲养个体的情况下成功，我们必须制定管理策略，将补充率提高到高于死亡率的水平。我们研究了2006年至2023年通过空中和地面调查使用无线电遥测收集的野生孵化美洲鹤雏鸟的表观每周存活数据。在这项研究中，我们使用Cox比例风险回归模型探讨了雏鸟存活与一系列潜在影响预测变量之间的关系，这些变量包括亲代经验、亲代生活史、栖息地、生态区域、天气和气候，以及巢穴和窝卵数特征。我们的结果表明，没有兄弟姐妹的雏鸟存活概率增加。存活概率也随着亲代集体经验和孵化后前4周的温暖天数（>32°C）增加。我们的数据表明，亲代经验是补充率的可靠预测指标。因此，成年个体的存活可能与雏鸟低存活率间接相关，因为有经验的成年个体经常从这个种群中消失。此外，我们的结果表明，从双卵巢中收集单个卵的努力可能会提高美洲鹤雏鸟的每周存活率。
