Dissertation Research: Ecological Effects of an Invasive Social Wasp on Endemic Hawaiian Arthropods

外来生物的引入是物种濒危的主要原因。通过研究本地物种和引进物种之间的相互作用，可以更好地了解入侵的原因和后果。本研究将通过对西部黄马蜂原产地（加利福尼亚）和引种地（夏威夷）的比较研究，探讨群居黄蜂入侵的潜在机制，并确定影响西部黄马蜂（Vespula pennsylvania）成功的特征。入侵性捕食者对本地物种的影响取决于接收群落的历史。由于夏威夷缺乏当地的群居昆虫，引进的西部黄马甲可能严重威胁到当地的无脊椎动物，包括食草动物、捕食者和传粉者。本研究采用经典生态学方法和现代分子方法相结合的方法(1)量化入侵黄马蜂对本土猎物和竞争类群的影响；(2)评估宾夕法尼亚黄马蜂与本土独居胡蜂资源利用的差异。初步结果表明，在这种入侵黄马甲存在的情况下，猎物和竞争对手的丰度显著下降。此外，本研究还探讨了宾夕法尼亚小黄蜂的觅食策略，并比较了宾夕法尼亚小黄蜂与本土独居黄蜂的资源消耗模式。本研究的更广泛的影响将是：(1)进一步加深我们对入侵成功的因素的理解；(2)有助于制定有效的管理策略，以尽量减少入侵的社会黄蜂，如宾夕法尼亚黄蜂的生态影响。

The introduction of non-native organisms is a leading cause of species imperilment. Through the study of interactions between native and introduced species, a better understanding of the causes and consequences of invasions may be obtained. This proposed research will examine the underlying mechanisms of a social wasp invasion and identify traits influencing the success of Vespula pensylvanica, the western yellowjacket, through comparative studies in its native range (California) and introduced range (Hawaii). The effect of invasive predators on native species depends upon the history of the recipient community. Because Hawaii lacks native social insects, the introduced western yellowjacket may seriously threaten endemic invertebrates, including herbivores, predators and pollinators. The proposed study uses a combination of classic ecological approaches and modern molecular methods (1) to quantify the effect of an invasive yellowjacket on native prey and competitor taxa, and (2) to assess differences in resource exploitation between V. pensylvanica and native solitary wasps. Preliminary results indicate that prey and competitor abundance decline significantly in the presence of this invasive yellowjacket. In addition, this research investigates the foraging strategies of V. pensylvanica and compares patterns of resource depletion by V. pensylvanica and native solitary wasps. The broader impacts of this study will be (1) to further our understanding of factors contributing to invasion success, and (2) to contribute to the development of effective management strategies that seek to minimize the ecological impacts of invasive social wasps, such as V. pensylvanica.