LTREB: Collaborative Research: Responses to Unpredictable Environmental Events: An Integrated Study of Stress Physiology, Environmental Cues, and Reproductive Success

大多数生物体所处的环境在空间和时间上各有不同。环境条件往往变化很快，很少或根本没有事先警告。生存和繁殖依赖于动物感知这些不可预测的事件并迅速和适当地调整生理和行为的能力。应激反应是动物改变行为和生理方向以应对环境中不可预测事件的一种机制。每年5月，当白冠麻雀回到它们的山区繁殖地时，天气条件极其不可预测，新鲜的雪可以暂时覆盖所有可用的觅食区域。这些鸟的行为可能会迅速而戏剧性地改变，以应对这些风暴。它们经常放弃繁殖区域，暂时迁徙到较低的海拔(即进行兼职的高度迁徙)，那里的天气条件不那么恶劣，食物也很容易获得。这项建议包括三种研究。首先，在一系列实地研究中，将调查食物可获得性、身体状况、应激生理学和兼性高度迁移之间的关系。其次，在实验室中，这些因素(食物可获得性、身体状况、压力生理和活动)之间的相互作用将在更可控的条件下进行测试。第三，将测量生殖成功，以评估环境、生理和适合度之间的功能关系。更广泛的影响：这项研究将做出几项一般性贡献。它将为几名本科生和研究生提供研究和培训机会。PIS非常重视本科生参与研究，这个项目将反映这一点。这个项目的几个方面(利用无线电遥测确定雪盖变化、食物可获得性、领土质量、鸟巢位置和鸟类的个体定位)是本科生项目的理想选择。该项目还有助于本科生参与实验室研究；在圈养研究中，这种鸟非常容易驯服。作为一个综合性的合作项目，它将促进大学之间的互动，并有助于开发生理学和行为学研究的领域桥梁方法。这项研究还将用于维护该物种繁殖生物学的长期数据库，该数据库由马丁·L·莫顿于1968年启动。随着环境条件(积雪深度、积雪覆盖、温度)、身体条件和繁殖时间的持续数据，我们可以检查可能受到全球气候变化影响的种群特征的长期趋势，如总体种群生殖产出或成虫年间存活率。

Breuner Hahn Abstract Most organisms occupy environments that vary in space and time. Environmental conditions often change rapidly, with little or no advance warning. Survival and reproduction depend on animals' ability to perceive these unpredictable events and to adjust physiology and behavior quickly and appropriately. The stress response is one mechanism by which animals can redirect behavior and physiology to cope with unpredictable events in the environment. When white-crowned sparrows return to their mountain breeding grounds each May, weather conditions are extremely unpredictable, and fresh snow can temporarily cover all available foraging areas. The birds' behavior can change rapidly and dramatically in response to these storms. They often abandon breeding territories and move temporarily to lower elevations (i.e., make facultative altitudinal migrations), where weather conditions are less severe and food is available. This proposal includes three kinds of studies. First, in a series of field studies the relationships between food availability, body condition, stress physiology and facultative altitudinal migration will be investigated. Second, in the laboratory, interactions between these factors (food availability, body condition, stress physiology and activity) will be tested under more controlled conditions. Third, reproductive success will be measured, permitting the evaluation of the functional relationships among the environment, physiology, and fitness. Broader impacts: This study will make several general contributions. It will provide research and training opportunities for several undergraduates and graduate students. The PIs place strong emphasis on undergraduate involvement in research, and this project will reflect that. Several aspects of this project (determination of changes in snow cover, food availability, territory quality, nest location and individual localization of birds using radiotelemetry) are ideal for undergraduate projects. The project also lends itself to involvement of undergraduates in laboratory studies; the birds are extremely tractable in captive studies. As an integrative, collaborative project, it will foster interactions among universities, and help to develop field-bridging approaches to the study of physiology and behavior. This study will also serve to maintain a long-term database on the breeding biology of this species, started by Martin L. Morton in 1968. With the continuing data on environmental conditions (snow depth, snow cover, temperature), body condition, and timing of reproduction, we can examine long-term trends in features of the population that may be affected by global climate change, such as overall population reproductive output or inter-year adult survivorship.