DISSERTATION RESEARCH: Ecological context shapes how consumers respond to predation risk

捕食者可以通过以下方式强烈影响生态系统的结构和功能： 营养级联 传统上，当捕食者吃掉中间消费者时，就会出现营养级联，从而对食物链的基础产生积极的间接影响。 然而，最近的研究表明，消费者的反捕食行为也可以驱动营养级联。消费者经常减少他们的觅食活动，以尽量减少对捕食者的脆弱性，但减少觅食的代价是减少能量摄入和增长。 因此，生理（例如，能量储备，代谢率）和环境条件（例如，资源可用性、环境压力）可能影响消费者如何平衡这些权衡。 例如，理论预测，当饥饿的风险也很高时（即，低能量储备或资源）。拟议的实验室和现场实验使用模型的食物链从新英格兰的岩石海岸，以检查消费者的反应捕食风险。 尽管有相当多的理论，更多的实证研究是必要的，以更好地了解生态环境的形状的增长捕食风险权衡猎物，最终确定的风险驱动的营养级联的强度和生态群落中的捕食者的影响。 此外，由于捕食风险的压力也会影响能量如何在食物链中向上转移，因此这项工作的见解将提高对生物多样性，食物网动态以及在自然生态系统管理中使用捕食者的重要性的科学理解（例如，黄石国家公园）。总部设在东北大学？的海洋科学中心（MSC），PI将通过暑期实习和许多完善的K-12外展计划在MSC的基础上从事不同背景的学生在他们的研究。 此外，拟议的实验将被整合到他们的基于实地的海洋生态学实验设计课程，该课程提供给东北大学的本科生和研究生。

Predators can strongly influence the structure and function of ecosystems through trophic cascades. Classically, trophic cascades emerge when predators eat intermediate consumers and thus have a positive, indirect effect on the base of the food chain. Recent work suggests, however, that the anti-predator behaviors of consumers can also drive trophic cascades. Consumers often reduce their foraging activity in order to minimize vulnerability to predators, but reduced foraging comes at the cost of reduced energy intake and growth. Hence, physiological (e.g., energy reserves, metabolic rate) and environmental conditions (e.g., resource availability, environmental stress) may influence how consumers balance these tradeoffs. For example, theory predicts that consumers may be more willing to accept increased predation risk while foraging when the risk of starvation is also high (i.e., low energy reserves or resources). The proposed laboratory and field experiments use a model food chain from the rocky shores of New England to examine consumer responses to predation risk. Despite considerable theory, more empirical research is necessary to better understand how ecological context shapes growth-predation risk tradeoffs in prey, which ultimately determine the strength of risk-driven trophic cascades and the impact of predators in ecological communities. Furthermore, because the stress of predation risk also affects how energy transfers up the food chain, insights from this work will improve scientific understanding of the importance of biodiversity, food web dynamics, and the use of predators in the management of natural ecosystems (e.g., Yellowstone National Park).Based at Northeastern University?s Marine Science Center (MSC), the PIs will engage students from diverse backgrounds in their research through summer internships and the many well-established K-12 outreach programs based at the MSC. Additionally, the proposed experiments will be integrated into their field-based Experimental Design in Marine Ecology course that is offered to undergraduate and graduate students at Northeastern.