When a species is introduced into a new location, it may escape, at least temporarily, from its natural enemies. In field surveys, we found that when the exotic, invasive mosquito, Aedes albopictus, invades new sites, it initially experiences reduced infection by its gut parasite, Ascogregarina taiwanensis. To determine the effect of this escape from parasitism on the competitive ability of A. albopictus, we performed a laboratory competition experiment in which infected and uninfected A. albopictus larvae were reared in microcosms alone and in competition with larvae of the native mosquito, Ochlerotatus triseriatus. We analyzed the effect of parasitism by A. taiwanensis on A. albopictus performance when subjected to intra- and interspecific competition across a range of larval densities, as well as the effect of A. albopictus parasitism by A. taiwanensis on the competitive impact of A. albopictus on O. triseriatus. At a density of 30 O. triseriatus larvae, O. triseriatus survivorship was significantly reduced by the addition of 30 unifected A. albopictus, but not by addition of 30 infected A. albopictus, and not by addition of 15 A. albopictus whether infected or uninfected. Although estimated finite rate of population increase (λ') showed similar trends, and was significantly affected by treatments, no pairwise differences in rate of increase were significant. Infection by A. taiwanensis also significantly prolonged A. albopictus female development time and reduced the intraspecific competitive effect of increased density of A. albopictus, but did not affect A. albopictus survivorship, mass, or estimated finite rate of population increase. Thus, when A. albopictus escapes from this parasite as it colonizes new sites, this escape may give it a small, but significant, added competitive advantage over O. triseriatus, which may facilitate range expansion of A. albopictus and enhance A. albopictus's initial impact on resident species.

中文翻译：

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逃离群居寄生虫会影响入侵蚊子的竞争性相互作用。

当一个物种被引入一个新的地方时，它可能会逃离，至少是暂时地，摆脱它的天敌。在实地调查中，我们发现当外来入侵蚊子白纹伊蚊入侵新的地点时，它最初会减少其肠道寄生虫 Ascogregarina taiwanensis 的感染。为了确定这种摆脱寄生对 A. albopictus 竞争能力的影响，我们进行了一项实验室竞争实验，在该实验中，感染和未感染的 A. albopictus 幼虫单独在微观世界中饲养，并与本地蚊子 Ochlerotatus triseriatus 的幼虫竞争. 我们分析了 A. albopictus 寄生对 A. albopictus 性能的影响，当在一系列幼虫密度下进行种内和种间竞争时，以及 A. albopictus 寄生对 A. albopictus 的影响。taiwanensis 对 A. albopictus 对 O. triseriatus 的竞争影响。在 30 只三线虫幼虫的密度下，加入 30 只未感染的 A. albopictus 显着降低了三线菌的存活率，但不会通过添加 30 只受感染的 A. albopictus 和 15 只感染或未感染。尽管估计的有限种群增长率 (λ') 显示出相似的趋势，并且受处理的显着影响，但增长率的成对差异不显着。A. taiwanensis 感染也显着延长了 A. albopictus 雌性发育时间并降低了 A. albopictus 密度增加的种内竞争效应，但不影响 A. albopictus 的存活率、质量或估计的种群增长有限速率。因此，当 A.