The evolutionary ecology of reproductive timing and rapid senescence in pacific salmon

拟议的研究将主要集中在鲑科鱼类生殖调度的进化生态学。在太平洋鲑鱼的大多数物种中，个体在一个短暂的繁殖季节内完成所有的繁殖成功，并在一段时间的快速生理衰退（衰老）后死亡。储存的能量用于迁移和繁殖，必须在生殖特征和身体维护之间仔细分配，以确保在产卵季节的生存。此外，迁徙、繁殖和衰老的时间对于确保卵子沉积、受精和越冬至关重要。我的研究的这一领域有三个目标：1）确定产卵期间能量储存（脂肪，蛋白质）和能量消耗的变化是否可以解释生殖寿命的变化（即，到达繁殖地和死亡之间的时期），2）确定衰老的年龄特异性模式如何响应于溯河和环境死亡率（捕食风险和高的河流温度）而演变，以及3）开发和测试关于为什么一些早到的雌性在到达繁殖地后延迟产卵的假设（即，预产卵等待）。这项研究对进化生物学家、保护生物学家、渔业和公众都很重要。它将提供关于自然选择如何演变生殖时间表的新信息，并将允许对自然环境或人为变化的后果进行预测。这些知识将为渔业和土地使用管理提供信息，以确保保护表型多样性。

The proposed research will focus primarily on the evolutionary ecology of reproductive scheduling in salmonid fishes. In most species of Pacific salmon, individuals achieve all their reproductive success in one short breeding season and die after a period of rapid physiological decline (senescence). Stored energy is used for migration and reproduction and must be carefully allocated between reproductive traits and body maintenance to ensure survival during the spawning season. Moreover, timing of migration, reproduction, and senescence are critically important to ensure that eggs get deposited, fertilized, and survive over the winter. This area of my research has three objectives: 1) determine whether variation in energy stores (fat, protein) and energy expenditure during spawning can explain variation in reproductive lifespan (i.e., the period between arrival at breeding sites and death), 2) determine how age-specific patterns of senescence evolve in response to anadromy and environmental mortality (predation risk and high stream temperatures), and 3) develop and test hypotheses for why some early-arriving females delay spawning after their arrival at breeding areas (i.e., pre-spawning waiting). The proposed research is important to evolutionary biologists, conservation biologists, the fishing industry, and the general public. It will contribute new information about how reproductive scheduling evolves by natural selection and will allow predictions to be made about the consequences of natural environmental or anthropogenic change. Such knowledge will inform fisheries and land-use management to ensure protection of phenotypic diversity.