Linking demography, life-history theory and conservation of birds

生态学家对影响野生动物生存和繁殖率的因素感兴趣，因为这些比率反映了野生动物的总体健康状况，并对种群规模和持久性产生巨大影响。在加拿大，许多迁徙野生动物物种受到当地发展以及世界其他地区影响造成的环境变化的威胁。为了实现长期目标，我和我的学生将继续检验生态理论，以加强我们对影响候鸟分布、丰度、繁殖和存活率的自然和人类相关过程的理解。然后，我们将利用有关这些过程的新知识来推荐管理计划或保护举措，并提高这些行动的成本效益。我们的主要项目侧重于候鸟，以及景观特征（特别是农业用地利用强度）和筑巢地点如何影响鸟类的个体质量及其生存率和繁殖率。我们将在不同农业集约化（和农药使用）地点测量树燕（一种空中食虫动物，一种严重依赖飞行昆虫获取食物的物种）筑巢季节的食物丰度，以评估不同的食物供应如何改变亲本的觅食和分散行为、生理和生存。在更广泛的范围内，我们还将调查两种草原筑巢鸭（绿头鸭和雌性针尾鸭）的生殖生态学，与个体质量和景观特征的测量相关。*据推测，动物的栖息地偏好与较高的繁殖成功率或生存率等益处相关，但大多数动物研究未能将栖息地选择与这些关键人口统计率联系起来。使用来自复制良好的本地和景观规模实验的几个独特数据集，我们将验证个体质量的新指数，并测试树燕、针尾鸟和绿头鸭的人口统计率与栖息地选择之间的正相关性。具体来说，通过结合多种创新技术，我们将进一步验证羽毛皮质酮（“应激”激素）作为不同物种个体品质综合指标的用途；将生存和繁殖成功与个体特征（例如年龄和质量、巢址使用和气候条件）联系起来；并使用强大的交叉寄养实验来评估筑巢地点选择的人口统计后果。重要的是，这些新的发现补助金研究将：（i）阐明影响存活率和繁殖成功的基本过程，（ii）应用这些知识来确定管理替代方案或提高保护计划的成本效益，以及（iii）为培训新兴生态学家（现在和将来必须应对日益复杂的环境挑战的个人）提供一个刺激且富有成效的场所。

Ecologists are interested in factors affecting survival and reproductive rates of wild animals because these rates reflect the general health of wildlife and have an enormous impact on population size and persistence. In Canada, many migratory wildlife species are threatened by environmental changes resulting from local developments as well as impacts in other parts of the world. To achieve long-term objectives, my students and I will continue to test ecological theories to strengthen our understanding about the natural and human-related processes that affect distribution, abundance, and reproductive and survival rates of migratory birds. We will then use our new knowledge about these processes to recommend management programs or conservation initiatives and to improve the cost-effectiveness of these actions. Our main projects focus on migratory birds, and how characteristics of landscapes - particularly the intensity of agricultural land use - and nest sites influence individual quality of birds, and their survival and reproductive rates. We will measure food abundance during the nesting season of tree swallows (an aerial insectivore, a species that relies heavily on flying insects for food) on sites of varying agricultural intensification (and pesticide use) to evaluate how parental foraging and dispersal behaviours, physiology and survival may be modified by variable food supplies. For broader scope, we will also investigate reproductive ecology of two species of prairie-nesting ducks (mallard and pintail females) in relation to measurements of individual quality and landscape characteristics.* Presumably, habitat preferences in animals are related to benefits such as higher reproductive success or survival, yet most studies of animals fail to link habitat selection to these key demographic rates. Using several unique data sets from well-replicated local and landscape-scale experiments, we will validate new indices of individual quality and test for positive correlations between demographic rates and habitat selection in tree swallows, pintails and mallards. Specifically, by incorporating a variety of innovative techniques, we will further validate the use of feather corticosterone (the "stress" hormone) as an integrated index of individual quality in diverse species; link survival and reproductive success to an individual's characteristics such as age and quality, nest site use and climatic conditions; and evaluate demographic consequences of nest site choices using powerful cross-fostering experiments. Importantly, these new Discovery Grant studies will: (i) clarify basic processes affecting survival rates and breeding success, (ii) apply this knowledge to identify management alternatives or to enhance the cost-effectiveness of conservation programs, and (iii) provide a stimulating, productive place for training emerging ecologists - individuals who will have to address increasingly complex environmental challenges, now and in the future.