Use of globally dispersed chemical tracers to measure in situ bioenergetic stress in fish and aquatic organisms

生物能量学领域提供了通过表达生活在给定环境中的生物体的总每日能量需求（每克动物每天所需的能量kJ）来建立动物的能量平衡的模型和方法。这些工具可以帮助理解生态系统中的能量限制如何影响自然界的模式，包括动物个体的行为（例如最佳觅食理论），动物种群的生长和健康，以及用于评估物种之间相互作用的相对强度。此外，许多类型的人类介导的应激源（例如有毒化学物质、栖息地丧失、全球变暖、物种入侵）引起生物能量影响，其首先影响动物代谢率，并且随着时间的推移损害动物的生长、生殖输出和适应性。测量动物在环境中的代谢率直接提供了生态压力效应的早期预警，并可用作帮助评估人口和生态系统健康的指标。 有几种方法可用于测量现场每日能量需求，也称为现场代谢率（FMR）的鱼。该提案将校准持久性有机污染物（持久性有机污染物）作为鱼类现场代谢率的示踪剂，并展示这些化学示踪剂对水生生态和生态压力感兴趣的主题的应用。多氯联苯等遗留污染物分布在全球各地，但由于环境浓度的降低，其毒性效应往往减少。这些化学物质有很强的前景作为动物生物能量学的被动示踪剂。本提案所述方法将使用实验室研究来证明，鱼类FMR的持久性有机污染物示踪方法得出的估计数与呼吸测定法等标准实验室方法相似。 最后，我将进行实验室，围隔生态系统和湖泊研究，以展示该方法的应用，以回答生态和生态压力的问题。一组案例研究将推断出浊度如何导致鱼类的生物能应力。 另一个项目将展示一系列湖泊中黄鲈种群的实际冰下能量需求。

The field of bioenergetics provides models and methods to establish the energy balance of animals by expressing the total daily energy needs (kJ of energy required per gram animal per day) of an organism living in a given environment. These tools can help understand how energy limitations in ecosystems contribute to patterns in nature including the behavior of individual animals (e.g. optimal foraging theory), growth and health of animal populations as well be used to evaluate the relative strength of interactions between species. In addition, many types of human mediated stressors (e.g. toxic chemicals, habitat loss, global warming, species invasions) cause bioenergetic impacts that first affect animal metabolic rate and over time compromise growth, reproductive output and fitness of animals. Measuring animal metabolic rates in the environment directly provides an early warning of ecological stressor effects and can be used as a metric to help assess population and ecosystem health. There are few methods available for measuring the in situ daily energy requirement, also known as field metabolic rate (FMR), of fish. This proposal will calibrate persistent organic pollutants (POPs) as tracers of field metabolic rates of fish and demonstrate the application of these chemical tracers to topics of interest to aquatic ecology and ecological stressors. Legacy pollutants such as PCBs are globally distributed, but as a consequence of decreases in environmental concentrations, are less often associated with toxic effects. These chemicals have strong promise for use as passive tracers of animal bioenergetics. The described methods in this proposal will use laboratory studies to demonstrate that POPs-tracer approaches of fish FMR yield similar estimates as standard laboratory methods such as respirometry. Finally, I will perform laboratory, mesocosm and lake studies to demonstrate the application of the method to answer ecological and ecological-stressor questions. One set of case studies will deduce how turbidity causes bioenergetic stress in fish. Another will demonstrate the actual under-the-ice energy requirements of yellow perch populations in a series of lakes.