Linking life-history theory, demography and conservation of birds

生态学家对影响野生动物存活率和繁殖率的因素很感兴趣，因为这些比率反映了野生动物的总体健康状况，并对种群规模产生巨大影响。在加拿大，许多野生物种受到环境变化的威胁，这些变化不仅来自当地的发展，而且来自世界其他地区的影响。北方繁殖的小飞鱼的种群数量已经下降，并保持在远低于保护目标的水平，而像树燕这样的物种则受到保护关注，因为严重依赖空中昆虫为食的物种的种群数量呈下降趋势。我们最近的研究结果表明，从孵化到独立（或第一次繁殖）的生命周期阶段迫切需要新的工作，因此新的发现资助项目旨在澄清为什么晚孵化的后代通常比早孵化的个体存活率低。这种模式可能与父母质量或食物丰富度的季节性下降，或疾病的发病率和严重程度较高有关。创新的实验结合长期的实地数据，对树燕和较小的scaup将有助于查明最可能的解释。

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. In Canada, many wildlife species are threatened by environmental changes resulting not only from local developments but also from impacts in other parts of the world. Populations of boreal-breeding lesser scaup have declined and remain well below conservation goals, whereas species like tree swallows are of conservation concern because of decreasing population trends in species that rely heavily on aerial insects for food. Our recent results suggest that new work is urgently needed on the life-cycle period from hatching to independence (or first breeding), so new Discovery Grant projects are designed to clarify why late-hatched offspring typically have lower survival than early-hatched individuals. This pattern could be related to seasonal reductions in parental quality or food abundance, or higher incidence and severity of diseases. Innovative experiments combined with long-term field data on tree swallows and lesser scaup will help to pinpoint the most likely explanation.