Avian phenotypic transitions; acting constraints, mechanisms and consequences

该项目的长期目标是确定在面临高能量需求的鸟类中限制表型灵活性的机制，并确定这些限制对健康的影响。在接下来的5年中，我们将研究在生活史阶段之间的过渡和环境条件变化期间发生的表型错配所导致的权衡。我们将(1)研究温度快速变化后鸟类冷耐力缓慢调整的机制。这将在UQAR鸟类设施进行，通过跟踪黑冠山雀（Poecile atricapillus）在温度突然下降或升高后的个体生理调整。我们还将(2)检查极端表型中有限灵活性的生理后果。这将在实验条件下完成，通过比较温暖和寒冷适应的松雀（Pinus Spinus）在增加的温度调节需求下的生理反应，以及在加拿大北极地区（East Bay 62°N, Alert 82°N），在那里，寒冷的专业雪雀（Plectrophenax nivalis）遇到的温度超过其耐热极限。在macp<e:1>研究中心与山雀一起工作，在两个北极地点进行森林和雪地狩猎，为确定代谢表现和对热约束的反应与适应性的生殖成分之间的关系提供了机会。这将在山雀中通过比较冬季代谢性能与繁殖成功率，并通过研究体温和喂养率与微栖息地温度和热避难所使用的关系来完成。在Alert与长途迁徙的红节（Canutus islandica）和红转石（Arenaria interpres）一起工作，我们还将(4)调查相互冲突的需求如何影响这些鸟类的迁徙恢复和准备。该计划将提供对形成鸟类适应性表型灵活性的生态和生理约束之间相互作用的综合理解。这个项目的影响将是重大的，因为每个项目的设计都是为了填补对预测动物如何应对环境变化至关重要的知识空白。学员将通过基础研究和/或保护生理学的应用工作，获得解决当今环境问题所需的技能和观点。这些科学家能够与来自不同学科的参与者合作，将有助于了解生物如何适应快速的环境变化和气候变化，这对加拿大来说是一个越来越重要的问题。

The long-term objectives of this program are to identify the mechanisms that limit phenotypic flexibility in birds facing high energy demands and to determine the consequences of these limits on fitness. Over the next 5 years, we will study the trade-offs resulting from phenotypic mismatches occurring during transitions between life-history stages, and during changes in environmental conditions. We will (1) examine the mechanisms underlying slow adjustments in avian cold endurance following rapid changes in temperature. This will be conducted at the UQAR Avian Facility by tracking individual physiological adjustments in black-capped chickadees (Poecile atricapillus) after a sudden drop or increase in temperature. We will also (2) examine physiological consequences of limited flexibility in extreme phenotypes. This will be done under experimental conditions by comparing the physiological responses of warm and cold acclimated pine siskins (Pinus Spinus) exposed to increased thermoregulatory demands and also across the Canadian Arctic (East Bay 62°N, Alert 82°N), where cold specialized snow buntings (Plectrophenax nivalis) encounter temperatures rising above their heat tolerance limit. Working with chickadees at the Macpès Research Forest and snow buntings at both Arctic sites provides the opportunity to (3) determine how metabolic performance and responses to thermal constraints relate to the reproductive component of fitness. This will be done in chickadees by comparing winter metabolic performance to reproductive success and by studying body temperature and provisioning rates of breeding buntings in relation with microhabitat temperatures and use of thermal refugia. Working at Alert with long distance migrant red knots (Canutus islandica) and ruddy turnstones (Arenaria interpres), we will also (4) investigate how conflicting demands can shape recovery from, and preparation for migration in these birds. This program will provide an integrated comprehension of the interplay between ecological and physiological constraints that shape adaptive phenotypic flexibility in birds. The impact of this program will be major because each project is designed to fill knowledge gaps that are critical to predict how animals cope with environmental changes. Trainees will acquire the skills and perspectives needed to tackle today's environmental issues, through fundamental research and/or applied work in conservation physiology. These scientists, able to work with actors from a variety of disciplines, will help understand how organisms adjust to rapid environmental alterations and climate change, a matter of increasing importance for Canada.