Abstract

Aquatic invaders often cause severe declines of native amphibian populations, either through competition, predation and/or alterations of the habitat. Such situation has raised additional concerns for the persistence of endemic species exhibiting rare and alternative phenotypes. Here, we experimentally assessed the impact of the invasive mosquitofish (Gambusia holbrooki) on adult newts (Lissotriton graecus) exhibiting paedomorphosis, the retention of larval traits such as gills, making them fully aquatic. Mosquitofish had a negative impact on paedomorphic newts by inducing both behavioral and phenotypic changes. Paedomorphic newts exhibited avoidance behavior and higher metamorphosis rates in the presence of fish. Both female and male newts responded by decreasing mobility and foraging activity. Females stopped investing in egg-laying in presence of fish and males metamorphosed earlier than females. Hence, our results show that mosquitofish introductions, particularly in areas with populations exhibiting paedomorphosis, might have detrimental consequences on the preservation of alternative developmental pathways. Both behavioral and phenotypic effects should be assessed to understand the impacts of introduced species.

中文翻译：

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一个微妙的威胁：入侵性蚊虫对原生古ed的行为和表型后果

摘要

水生入侵者通常通过竞争，捕食和/或栖息地改变而导致本地两栖动物种群大量减少。这种情况引起了人们对表现出稀有和替代表型的地方性物种的持久性的关注。在这里，我们通过实验评估了侵入性蚊子（Gambusia holbrooki）对成年new（Lissotriton graecus）的影响。）表现出粉刺变质，保留g等幼虫性状，使其完全水生。蚊鱼通过诱导行为和表型变化，对拟态new产生负面影响。在有鱼的情况下，古态new表现出回避行为和较高的变态率。雌性和雄性new均通过减少活动性和觅食活动来应对。在有鱼的情况下，雌性停止投资产卵，雄性比雌性早变态。因此，我们的结果表明，引入蚊虫，特别是在种群表现出粉刺异样的地区，可能对保留替代性发育途径产生不利影响。应评估行为和表型效应，以了解引入物种的影响。