Plasticity of Life History Traits in Arctic Charr: Use of Retrospective Data to Couple Migration Data with Environmental Variation

形态和环境历史之间的关系将被研究。研究计划的目的是：1)提炼和发展前景看好的新兴技术，从耳石碳酸盐和档案标签中提取个体鱼类过去生活史和环境条件的记录，2)探索一种新的方法，通过将实验验证的耳石技术应用于各种自然条件下的个体，研究环境条件对形态和生活史可塑性的影响。其目标是在耳石的化学结构与环境因素之间建立追溯和预测关系：了解影响化学结构的环境因素之间的相互作用；将耳石中编码的环境信息与实地观察相结合，以评估生物和非生物参数对建立北极木炭不同生活史模式的重要性。每日生长增量、耳石中元素的比率和档案标签信息将被用来反算单个鱼的环境和身体变化。技术将被应用于：1)评估生活史数据(即生长速度、年龄结构、孵化日期分布、产卵时间等)。在生活史策略方面。2)确定关键生活史转变的重要性、影响转变开始的条件，并通过调查鱼耳石的结构和元素组成，确定迁徙计划(无论个人是迁徙的还是居民、初次迁徙的年龄、前迁徙的个体是否将恢复居留的生活史战略，以及迁徙前后的事件)。3)发现不同地理区域之间与水文、营养或生境条件有关的生长和生活史的差异。4)精确计时几个关键的生活史转变的发生，并将它们与环境变量相关联。拟议的研究结果将为鱼类生活史的研究提供一个范例。这种知识对于我们理解适应生活史模式的基本过程至关重要，并将使我们有可能将生长和迁徙与环境发生联系起来。这将为洞察物种与其环境之间相互作用的生态过程提供洞察。在一般生态学意义上，这种信息具有重大和基本的重要性，因为它将允许重建复杂的环境相互作用，这些相互作用在个体之间综合起来，以提供个人、种群和物种家族的短期稳定和长期进化。

The relationships between morphology and environmental history will be investigated. The plan of research is aimed at 1) refining and advancing promising, but nascent, techniques for extracting a record of the past life history and environmental conditions encountered by individual fish from otolith carbonate and archival tags, and 2) exploring a fresh approach to investigate the influence of environmental conditions upon morphology and life history plasticity by applying experimentally validated otolith techniques to individuals from a multitude of natural conditions. The goals are to establish retrospective and predictive relationships between the chemical structure of otoliths and environmental factors: to understand interactions among environmental factors that affect chemical structure; and to combine the environmental information encoded in otoliths with field observations to evaluate the importance of biotic and abiotic parameters to the establishment of divergent life history patterns in Arctic charr. Daily growth increments, the ratios of elements in the otolith and archival tag information will be used to back-calculate environmental and somatic changes for individual fish. Techniques will be applied to: 1) Assess life history data (i.e., growth rates, age structure, hatch date distribution, timing of spawning, etc.) in terms of life history strategies. 2) Establish the importance of critical life-history transitions, conditions affecting their onset, and derive migrational schemes (whether an individual is a migrant or a resident, age at first migration, whether a former migrant individual will resume a resident life history strategy, and the events leading and following migration) by investigating the structural and elemental composition of fish otoliths. 3) Detect differences in growth and life histories between different geographical areas as related to hydrographic, trophic or habitat conditions. 4) Precisely time the occurrence of several pivotal life history transitions and correlate them with environmental variables. The results of the proposed research will provide a paradigm to the study of fish life histories. Such knowledge is vital to our understanding of the processes fundamental to adaptable life history patterns and would make it possible to link growth and migration to environmental occurrences. This would provide insight to the ecological process of interactions between a species and its environment. In a general ecological sense such information is of great and fundamental importance since it will allow to reconstruct the complex environmental interactions that are integrated among individuals to provide for both the short term stability and the long term evolution of families of individuals, populations and species.