DISSERTATION RESEARCH: An Experimental Test of Generalist Foraging Behavior as a Community Stabilization Mechanism

物种可能因为许多原因而变得罕见或常见。科学家们越来越感兴趣的是，一个物种丰度的这种变化如何影响其他物种，特别是那些吃稀有物种的物种。 一些科学家认为，一个物种的稀少会导致依赖于这个物种的其他物种的稀少，这可能会导致许多地方的灭绝，甚至可能导致整个生态系统的崩溃。 其他科学家不同意。 他们认为，如果一个物种可能与另一个物种竞争，那么一个物种的减少可以使其他物种受益，从而形成一个稳定的生态系统，其中物种数量相对于减少的物种数量保持总体平衡。 预测植物和动物对环境变化的脆弱性的关键是弄清楚这些相反的观点中哪一个最有可能。 这种理解将有助于管理人员、决策者和科学家制定支持地球生命多样性的战略。该项目的目标是测试如何沿海生态系统的干扰，特别是，是否顶级捕食者可以调整到丰富的变化，在其prey.This研究使用的捕食性海螺在俄勒冈州海岸，研究不同的可能觅食策略的通才捕食者影响岩石潮间带群落的稳定性。研究人员将在实验室中使用在不同猎物上训练的海螺，在野外复制不同的通才觅食方法（例如，恒定的猎物偏好和适应性觅食）。海螺将暴露于现场的两个自然脉冲补充扰动。 研究人员将利用扰动后物种密度的变化来确定群落的恢复力和抵抗力。这将使研究人员能够研究通才在促进社区稳定方面所起的作用，以及什么形式的通才觅食最有可能稳定社区。这项研究将支持研究生和本科生的培训，并将通过为科学中心举办展览，解释食物网的概念以及食物网如何影响科学中心游客的日常生活，提供推广机会。

Species can become rare or common for many reasons. Scientists are increasingly interested in how such changes in the abundance of one species can impact other species, particularly those that eat species that become rare. Some scientists think that the rareness of one species leads to the rareness of other species that rely on this species, potentially causing a lot of local extinctions -- perhaps even the collapse of an entire ecosystem. Other scientists disagree. They think that declines in one species can benefit other species if the first species might compete with the second, leading to a stable ecosystem in which there is an overall balance in the number of species that are increasing relative to those that are decreasing. Key to predicting the vulnerability of plants and animals to changes in their environment is figuring out which of these opposing views is most likely. Such understanding will help managers, policy makers and scientists develop strategies to support the diversity of life on earth. The goal of this project is to test how a coastal ecosystem responds to disturbances and, in particular, whether a top predator can adjust to changes in the abundance in its prey.This research uses a predatory whelk on the Oregon coast to examine how different possible foraging strategies of generalist predators influence the stability of rocky intertidal communities. The researchers will use whelks trained on different prey in the laboratory to replicate different methods of generalist foraging in the field (e.g., constant prey preferences and adaptive foraging). The whelks will be exposed to two natural pulse recruitment perturbations in the field. Researchers will use the changes in species densities following the perturbations to determine the resilience and resistance of the communities. This will allow the researchers to examine the role that generalists play in promoting community stability and what forms of generalist foraging are the most likely to stabilize communities. This study will support the training of a graduate and undergraduate students and will provide opportunities for outreach through the development of an exhibit for a science center that explains the concept of food webs and how food webs influence the everyday lives of visitors to the science center.