Resources at multiple trophic levels mediate foraging by omnivores

多个营养级的资源介导杂食动物的觅食

• 批准号: 288220-2009
• 负责人: VanLaerhoven, Sherah
• 金额: $ 1.38万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=427254
• 关键词: Resources; multiple; trophic; levels; mediate

My research focuses on interactions between insects within and between trophic levels in different ecosystems. My long term goal is to understand the similarities and differences of these food web interactions when the components of the food web changes. In particular, I am interested in how omnivores, which by definition feed at multiple levels within food webs, change their feeding decisions when presented with different types of resources and how the feeding decisions by omnivores impact other members of the food web. Omnivores must make decisions between feeding on basal resources that may be readily available, but of low quality, with searching for prey resources, which may be scarce, but of high quality. Thus, omnivores are faced with making foraging decisions where resources vary in quality, type and abundance. My central hypothesis is that omnivores will feed on other beneficial insects (high quality, high risk prey) depending on the type and quality of other food sources. I will test this hypothesis using two different omnivores that feed within two different food webs, one based on plants and one based on dead animals. These two food webs differ in that for insect omnivores that live on plants, plant resources are unlimited, whereas, for insect omnivores that live on dead animals, the animal resource is depleted over time. This allows comparisons of omnivory when both basal and prey resources vary in type, quality and abundance. It also allows me to achieve my short term goal of evaluating to what degree plant-based omnivores provide insight to mechanisms of omnivory on a broader scope. My research promises to make a strong contribution to our understanding of the role of resources at multiple trophic levels mediating omnivory. By studying insect food webs in different ecosystems, I explore the behavioural ecology of animals living in very different environments and thereby develop a broader understanding of community structure and food web dynamics.

我的研究重点是不同生态系统内和营养水平之间昆虫之间的相互作用。我的长期目标是了解当食物网的组成部分发生变化时，这些食物网相互作用的异同。我特别感兴趣的是，根据定义，杂食动物在食物网中的多层次进食，当出现不同类型的资源时，杂食动物如何改变它们的进食决定，以及杂食动物的进食决定如何影响食物网的其他成员。杂食动物必须在取食可能容易获得但质量较低的基础资源和寻找可能稀缺但质量较高的猎物资源之间做出决定。因此，杂食动物面临着在资源质量、类型和丰度不同的情况下做出觅食决定的问题。我的主要假设是，杂食动物会根据其他食物来源的类型和质量，以其他有益昆虫（高质量、高风险的猎物）为食。我将用两种不同的杂食动物来测试这个假设，它们以两种不同的食物网为食，一种以植物为食，另一种以死去的动物为食。这两种食物网的不同之处在于，对于以植物为食的杂食昆虫来说，植物资源是无限的，而对于以死去的动物为食的杂食昆虫来说，动物资源随着时间的推移而耗尽。当基础和猎物资源在类型、质量和数量上都不同时，这就可以对杂食动物进行比较。这也让我实现了我的短期目标，即评估以植物为基础的杂食动物在多大程度上在更广泛的范围内提供了对杂食机制的洞察。我的研究有望对我们理解多种营养水平的资源介导杂食的作用做出重大贡献。通过研究不同生态系统中的昆虫食物网，我探索了生活在不同环境中的动物的行为生态学，从而对群落结构和食物网动态有了更广泛的了解。