Multispecies competition, indirect effects, and invasion in mosquito communities

描述（由申请人提供）：容器蚊在医学上具有重要意义，其中白纹伊蚊、三角纹伊蚊、淡色库蚊/致倦库蚊等是人类疾病的媒介。包括白纹伊蚊和最近的日本纹蚊在内的连续入侵的容器蚊子到达北美是很重要的，因为这些物种可以作为媒介，但也因为它们改变了社区的组织，这样做可能对人类疾病产生间接影响。了解容器群落及其入侵者的生态将是了解这些与人类有关的栖息地中的蚊子如何、在何处以及何时可能成为健康威胁的宝贵工具。为了了解相互作用的多物种蚊子如何直接或间接地相互影响，以及这些影响对媒介种群的影响，该项目有三个具体目标。具体目的1是确定伊蚊和赤纹伊蚊竞争种之间的直接效应和间接效应。我们将采用一种检测间接效应的统计设计，在涉及4种蚊子的实验室实验中检验竞争物种的间接效应影响蚊子种群动态的假设。在一个相关的野外实验中，我们将使用类似的设计来验证这样的假设：在自然界中，竞争物种的直接和间接影响会影响非本地物种成功入侵容器群落的概率。具体目标2是确定竞争和殖民化成功之间的权衡作为物种共存机制在容器群落中的重要性。我们将对伊蚊和斑蚊物种之间的共存是竞争能力和殖民化能力之间权衡的结果这一假设的两个预测进行验证：预测1是伊蚊和斑蚊物种之间存在竞争等级。这将在一套实验室竞赛实验中进行测试。预测二是物种在空位上定居的能力与它们在竞争等级中的位置呈负相关。我们将通过一项旨在量化容器蚊定殖能力的现场实验来验证这一预测。具体目的3是确定两个主要的多物种容器蚊群：伊蚊+革纹蚊与库蚊之间发生的竞争效应。我们将开发排除伊蚊+黄纹伊蚊的方法，并利用这些方法验证伊蚊+黄纹伊蚊之间不对称的直接和间接相互作用导致当地库蚊种群减少的假设。居住在容器中的蚊子可能是一个重大的公共卫生问题，因为其中许多物种是人类疾病的媒介（例如拉克罗斯脑炎、西尼罗河病毒性脑炎、圣路易斯脑炎），而且这些容器通常发生在人们居住、工作和娱乐的地方附近。该项目调查了这些蚊子对彼此的影响，这些影响如何影响这些物种的种群动态，以及非本土物种是否可以入侵容器群落。通过调查整个蚊子群落的结构和功能，我们将更好地了解这些媒介目前和未来的公共卫生威胁，

DESCRIPTION (provided by applicant): Container-dwelling mosquitoes are medically important, with Aedes albopictus, Ochlerotatus triseriatus, Culex pipiens/quinquefasciatus, among others, acting as vectors of human diseases. Arrivals in North America of successive invasive container mosquitoes, including, among others Aedes albopictus, and more recently Ochlerotatus japonicus, are important because these species can act as vectors, but also because they alter the organization of the community and in so doing may have indirect impacts on human disease. Understanding the ecology of container communities and their invaders will be a valuable tool for understanding how, where, and when mosquitoes in these human-associated habitats may become health threats. To understand how multispecies assemblages of interacting mosquitoes may affect one another directly and indirectly, and the consequences of those effects for vector populations, this project has 3 specific aims. Specific aim 1 is to determine the roles of direct and indirect effects among competing species of Aedes and Ochlerotatus. We will use a statistical design for detecting indirect effects in a laboratory experiment involving 4 species to test the hypothesis that indirect effects of competing species affect mosquito population dynamics. In a related field experiment, we will use a similar design to test the hypothesis that in nature, direct and indirect effects of competing species affect probability of successful invasion of container communities by non- native species. Specific aim 2 is to determine the importance of a trade-off between competitive and colonization success as a mechanism of species coexistence in container communities. We will test two predictions of the hypothesis that coexistence among Aedes and Ochlerotatus species results from a tradeoff between competitive and colonization abilities: Prediction 1 is that there is a competitive hierarchy among Aedes and Ochlerotatus species. This will be tested in a set of laboratory competition experiments. Prediction 2 is that species' abilities to colonize vacant sites are negatively correlated with their positions in this competitive hierarchy. We will test this prediction using a field experiment designed to quantify colonization ability of container mosquitoes. Specific aim 3 is to determine the competitive effects occurring between the two major multispecies groups of container-dwelling mosquitoes: Aedes + Ochlerotatus vs. Culex. We will develop methods for exclusion of Aedes + Ochlerotatus and use those methods to test the hypothesis that asymmetrical direct and indirect interactions between these two groups result in Aedes + Ochlerotatus presence reducing local populations of Culex. Container-dwelling mosquitoes can be a significant public health problem because many of these species are vectors of human disease (e.g., La Crosse Encephalitis, West Nile Viral Encephalitis, St. Louis Encephalitis), and because these containers often occur in close proximity to the places people live, work, and take recreation. This project investigates the effects that these mosquitoes have on one another, how those effects may influence the population dynamics of these species, and whether nonnative species can invade container communities. By investigating the structure and function of this entire community of mosquitoes, we will gain a better understanding of current and future public health threats from these vectors,