LTREB Collaborative Proposal: Large-scale removal of introduced ants as a test of community reassembly

将非本地物种引入生态系统是一种普遍存在的环境变化形式，其负面影响包括物种数量和类型的变化、生态系统服务受到损害，以及在某些情况下本地物种的灭绝。然而，令人惊讶的是，关于引入物种消失后生态系统恢复能力的信息很少。特别是，只有少数关于物种入侵的研究将入侵前的长期数据与入侵者清除实验结合起来，在足够长的时间尺度上确定本地物种组合是否完全恢复。该项目将研究阿根廷蚂蚁（一种常见的、广泛分布的、具有生态破坏性的引进物种）在景观尺度上被移除后，本地蚂蚁群落的重组。在入侵者被清除后，研究人员将量化本地蚂蚁群落在遗传多样性、物种多样性和生态功能方面的恢复。要进一步阐明生态系统从这种类型的环境变化中恢复的速度和程度，就需要采用多种方法，例如这里所采用的方法。与这项工作相关的更广泛的影响包括为加州大学圣地亚哥分校和加州大学伯克利分校的博士生提供研究支持，为加州州立大学海峡群岛分校（一所四年制西班牙裔服务机构）的本科生提供研究经验，以及一个专注于了解入侵物种生态影响的高中外展项目。实验性地去除数量上占优势的引进物种，可以为研究群落重组提供无与伦比的机会。入侵者清除实验可以揭示重组是如何受到在给定系统内作用的过程的影响的，或者，反映在更大的空间尺度上作用的过程。本研究的目的是量化非本地阿根廷蚂蚁在景观规模移除后，本地蚂蚁群落恢复的结构（遗传多样性、物种多样性）和功能（营养地位、生态功能）组成部分。随着加州圣克鲁斯岛的大规模根除治疗现已完成，从这一点开始的项目将在十年的时间尺度上量化本地蚂蚁的重组。该研究的核心假设是，本地物种组合将从入侵者的移除中恢复，但前提是在时间尺度上测量重组(1)与焦点本地物种的生活史相称；(2)包括组合形成过程中种间相互作用的变化。本研究将对入侵生物移除后本地群落恢复结构和功能的能力进行前所未有的测试，并对控制重要陆生动物群落丰富度、组成和生态功能的因素提供新的信息。

The introduction of non-native species into ecosystems is a pervasive form of environmental change with negative impacts ranging from shifts in the number and types of species, compromised ecosystem services and, in some cases, extinction of native species. Surprisingly little information exists, however, regarding the capacity of ecological systems to recover after introduced species removal. In particular, only a handful of studies on species invasions combine long-term, pre-invasion data with invader-removal experiments over temporal scales long enough to determine whether or not native species assemblages fully recover. This project will examine the reassembly of native ant communities following the landscape-scale removal of the Argentine ant, a common, widespread and ecologically disruptive introduced species. Following invader removal, researchers will quantify recovery of native ant assemblages with respect to their genetic diversity, species diversity, and ecological function. Multiple approaches, such as those to be employed here, are required to further clarify the rate and extent to which ecosystems recover from this type of environmental change. Broader impacts related to this work include research support for PhD students from UC San Diego and UC Berkeley, a research experience for undergraduates program for students from California State University, Channel Islands (a four-year Hispanic Serving Institution), and a high school outreach program focused on understanding ecological effects of invasive species. The experimental removal of numerically dominant, introduced species can provide unparalleled opportunities to examine community reassembly. Invader-removal experiments can shed light on how reassembly is influenced by processes acting within a given system or, alternatively, reflects processes acting at larger spatial scales. The objectives of this research are to quantify the structural (genetic diversity, species diversity) and functional (trophic position, ecological function) components of the recovery of native ant assemblages following landscape-scale removal of the non-native Argentine ant. With large-scale eradication treatments on Santa Cruz Island, California, now complete, the project from this point forward will quantify native ant reassembly over a decadal time scale. The central hypothesis is that native assemblages will recover from invader removal but only if reassembly is measured over temporal scales (1) that are commensurate with the life history of focal native species, and (2) that encompass how interspecific interactions change during assemblage formation. This research will provide an unprecedented test of the capacity for native assemblages to regain structure and function after invader removal and also yield novel information about the factors that control the richness, composition and ecological function of an important terrestrial animal assemblage.